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Tommie, Ibert. "Phthalate replacement by fast fusing non-phthalate plasticizer." Thesis, KTH, Skolan för kemivetenskap (CHE), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-184858.
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A key trend in the PVC market is to replace or decrease the amount of phthalate plasticisers used due to increasing health concerns. Therefore, the demand for non-phthalate based plasticisers is growing rapidly. Mineral oils are used in a variety of rubber and polymer applications as plasticisers; however, due to the lower polarity their applicability in PVC compounds is limited. Therefore, these materials are typically used as secondary plasticiser along with a primary for the purpose of improved properties and cost reduction. Some of the non-phthalate based solutions are fast fusing plasticisers, which act like solvents and have too rapid and too high plasticizing effect. This makes the compounding difficult and could cause problems in production. These substances have good compatibility with mineral oils, and using them together in PVC compounds can help the compounding issue by reducing the solvent power and increasing the fusion time to a level where the production parameters are similar to compounding with phthalates. The aim of this study was to evaluate the use of mineral oils as a secondary plasticiser in a non-phthalate system for PVC. Four different grades of mineral oil and three non-phthalate plasticisers were used in compounding and compression moulding of PVC sample films. Mechanical, physical and chemical testing were done to assess the properties in a comparative study with phthalate plasticized PVC. Tensile testing and hardness measurements showed that the mineral oils did not contribute with any plasticizing effect for the non-phthalate plasticisers tested in the study. The hardness was instead slightly increased for all the sample films that contained mineral oil. This indicates that the mineral oil either is less efficient than the primary plasticiser or that it affects the primary plasticisers intramolecular shielding between the PVC chains. The shrinkage test showed that the migration of mineral oil was acceptable, especially the thicker grades of mineral oils had low migration. Colour stability test showed that the thicker mineral oil grades had some problems with discolouration. The discolouration is probably related to content of polyaromatics and oxidation stability.
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Nguyen, Bryan. "Gene Expression Changes from Exposure to Phthalates in Testicular Cells." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/22913.
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Phthalates are industrial plasticizers with a wide range of applications. Di-(2-ethylhexyl) phthalate (DEHP) is one of the most highly produced and frequently studied phthalates. Its metabolite, mono-(2-ethylhexyl) phthalate (MEHP) is known as a testicular toxicant. The objective of this study was to examine expression of the genes of interest in testicular germ cells exposed to MEHP in a dose- and time-dependent manner at concentrations of 1µM, 10µM, and 100µM at 24, 48, 72 and 96hr time points. The genes consisted of Testisin, GSPT1, and MGMT genes which are a tumor suppressors, phase II xenobiotic metabolizing enzyme and DNA repair gene respectively. These genes were analyzed by Quantitative Real Time PCR (RT-PCR). The results revealed an overall down-regulation for each gene as the concentration and/or time increased. Testisin was the focus of the gene expression analysis. Testisin is epigenetically silenced in testicular germ cell tumors (TGCT) by DNA methylation at the 5’CpG island of the gene. To investigate if MEHP is capable of DNA hypermethylation, a co-exposure with 5-azacytidine (demethylating agent) was conducted. Compared with the 5-azacytidine treatment alone, there was a significant down-regulation of the Testisin gene in the co-exposure. This suggests that MEHP may down-regulate Testisin gene expression by DNA methylation. These findings provide evidence that MEHP can alter the expression of Testisin, GSTP1 and MGMT, genes that are associated in the risk of developing testicular germ cell tumors. In addition, results indicated that MEHP may cause DNA methylation leading to the down-regulation/silencing of genes such as Testisin.
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Balck, Marianne. "Phthalates in preschool dust : the relation between phthalates and parameters in the preschool environment." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-262076.
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Children are constantly exposed to many chemicals via the products they come in contactwith in their everyday life. One chemical group is phthalates, the most commonly usedplasticisers in the world. Phthalates are used mainly in PVC plastic products like floors, toys,food containers and wallpaper but they are also used in rubber, glue, paint, cables etc. Sincethese chemicals are weakly chemically bound to the PVC they can leak and migrate to the air,food, water and skin. Children are exposed to phthalates mainly through food, but because ofthe hand to mouth behaviour they are also exposed via dust inhalation and dust ingestion.About ten years ago regulations of the most toxic phthalates in toys and child care productswere implemented in the EU and from February 2015 it is a general prohibition for the use ofDEHP (diethylhexyl phthalate), DnBP (di-n-butyl phthalate), DiBP (diisobutyl phthalate) andBBzP (butyl benzyl phthalate). DiNP (diisononyl phthalate) is a relatively new phthalate andit has replaced DEHP to some extent in floors and toys. In phthalate free products DINCH(1,2-cyclohexane dicarboxylic acid diisononyl ester) is one of the plasticizer replacingphthalates. The banned phthalates have been shown to cause adverse effects on reproductionand recent research also investigates links between phthalate exposure and asthma and allergysymptoms in children. More experimental animal studies are needed to further investigate theasthma and allergy correlation. In the present project dust samples were collected from 30 preschool indoor environments inthe Stockholm city area to evaluate the levels of the six substances mentioned and thephthalate DEP (diethyl phthalate). The main aim of this thesis project was to search forrelations and links between the phthalate concentrations in dust and parameters from theindoor environment in preschools. Studied parameters are e.g. construction year, floor type,cleaning routines and quantity of toys and furniture made of plastic or foam. The project wascommissioned by the Swedish EPA and performed at the Institute of Environmental Medicine(IMM) at Karolinska Institutet. A negative relation was found between dust phthalate (DEHP and DnBP) concentrationand construction year. Also rooms with old PVC floors had higher concentrations of DEHPand DnBP in dust than rooms with new PVC floors. There was also a trend that dust frompreschools with PVC floors had higher DiNP concentration than dust from preschools withother floor types. The preschools that used foam mattresses for resting had higher DiNPconcentrations than those with no foam mattresses. Most preschools had new foammattresses, which could indicate a more common use of DiNP in new mattresses or mattress2covers compared to old mattresses that contains more DEHP. The four Waldorf preschoolsthat participated had lower DiNP dust concentrations than the other preschools, which wasexpected since Waldorf orientation includes using as little plastic material as possible. Norelation was found between the phthalate dust concentrations and the quantity of toys made ofsoft plastic in the sampled area. Many preschools had made a plastic inventory where they removed old and soft plastic toysand material. Also many preschools recently replaced old foam mattresses used for resting.This could be due to the big chemical focus in the media and authorities and the brochuresthat have been sent out the last couple of years about what preschool can do to decrease thechemical exposure of children. This interest and awareness seen in the preschools waspositive and hopefully the trend spreads to more preschools. Since children spend a big part oftheir time at preschools it is an important mission for society and the government to decreasethe exposure to hazardous chemicals there. Hopefully what has been done so far is just thebeginning.
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Mitten, Lauren. "Phthalates: Science, Advocacy, and Biomonitoring." Scholarship @ Claremont, 2015. http://scholarship.claremont.edu/scripps_theses/614.
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Phthalates are a class of ubiquitous environmental contaminants that cause health problems including reproductive disorders, asthma, and obesity. Advocacy against phthalates has been taking place in the US since the mid-1990s, and eight in-depth interviews were conducted with advocates and scientists in order to construct a history of this advocacy. There have been a variety of campaigns and victories; those around medical devices, children’s products, and personal care products are examined in detail. Phthalate exposure data for a representative sample of the US population indicates that exposure to DEP, DEHP, DnBP, and BBzP went down between 1999 and 2010. As these were the phthalates that had the largest volume of advocacy during the period researched, this decrease suggests that advocacy around specific phthalates is effective in reducing exposure and that more advocacy around phthalates, and potentially other harmful chemicals, could result in further decreased exposure and improved health in the US population. Additional research using more finely graded biomonitoring data would help deepen understanding about correlations between advocacy and phthalate exposure. In reviewing the health effects of phthalates, it was found that a disproportionate amount of the research is on male reproductive health effects, which is partially responsible for the fact that a disproportionate amount of phthalate advocacy is on heath effects relating to men, particularly male babies. Both phthalate science and advocacy sometimes treat women instrumentally, objectifying them or regarding them as incubators. To combat this, scientists could do more research on the health effects of phthalates on women and advocates could take more care not to neglect or instrumentalize women in their efforts to reduce phthalate exposure for all people.
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Matinise, Nolubabalo. "Electrolytic determination of phthalates organic pollutants with n nostructured titanium and iron oxides sensors." Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1177_1305892404.
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This work reports the chemical synthesis, characterisation and electrochemical application of titanium dioxide (TiO2) and iron oxide (Fe2O3) nanoparticles in the determination of phthalates. The other part of this work involved electrochemical polymerization of aniline doped with titanium and iron oxide nanoparticles for the sensor platform in the electrolytic determination of phthalates. The TiO2 and Fe2O3 nanoparticles were prepared by sol gel and hydrothermal methods respectively. Particle sizes of 20 nm (TiO2) and 50 nm (Fe2O3) were estimated from transmission electron microscopy (TEM) The other technical methods used in this study for the characterization of the TiO2 and iron oxide Fe2O3 NPs were SEM, XRD and UV- visible spectroscopy. Cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties of the nanoparticles. These electrochemical studies of the nanoparticles were performed with a Fe2O3 or TiO2/nafion/glassy carbon membrane electrode in 0.1 M phosphate buffer (pH 7.0) and 0.1 M lithium perchlorate (pH 6.8) under an aerobic condition.
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Oliver, Roly. "Phthalates in wastewater : types, occurence and fate during treatment." Thesis, University of Portsmouth, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411553.
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黃之玠 and Evelyn Wong. "Phthalates, an emerging endocrine disrupting chemical: exposure, effects and human health." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41549521.
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Wong, Evelyn. "Phthalates, an emerging endocrine disrupting chemical exposure, effects and human health /." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41549521.
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Bui, Tuong Thuy. "Assessing human exposure to phthalates, alternative plasticizers and organophosphate esters." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-141808.
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Phthalate esters (PEs) and organophosphate esters (OPEs) are common indoor pollutants frequently detected in environmental (dust, air), personal (hand wipes, diet) and human matrices (urine, serum etc.). In this thesis, mathematical models were used to establish links between intake and body burden for a comprehensive dataset based on a Norwegian study population. Also, the relative importance of different PE uptake pathways was assessed and discussed. Furthermore, the suitability of human nails as an alternative, non-invasive biomonitoring matrix for PEs was investigated. Additionally, information regarding alternative plasticizers to PEs was collected and presented extensively. Results showed that for PEs (paper II), daily intakes based on external exposure media agree with back-calculations using urinary metabolite concentrations, leading to the conclusion that human exposure for the general adult population is well understood and that the most important uptake routes were captured. Overall intake levels are comparable or lower than level presented in recent comprehensive studies and hazard quotients were well below 1 (low risk). As expected, diet was found to be the most important uptake route for all PEs. For lower molecular weight PEs, inhalation becomes a strong contributing pathway whereas for higher molecular weight PEs, dust ingestion was also important. Daily intake based on hand wipes was found to be much lower than the estimated total dermal intake based on air, dust and personal care products, questioning the relevance of hand wipes to represent total dermal exposure. Human nails were found to be unsuitable for replacing urine as a biomonitoring matrix for PEs as internal intake (from blood) cannot explain measured nail concentrations and uptake from air is too slow to reach observed concentrations within a realistic time frame (paper III). Hence, the kinetic links between intake and nail concentrations could not be established. Although exposure to traditional PEs is decreasing, use and body burden of some alternatives are increasing (paper I). Fortunately, most alternative plasticizers have favorable toxicological properties, resulting in low risk for humans. In contrast to PEs, OPEs still remain a group of poorly studied substances in terms of human exposure (paper IV). Due to lack of information regarding human metabolism, reliable links between intake and concentrations in serum and urine could not be established. Modelling results showed that concentrations in serum, and to some extent, urine, were underestimated for 2 compounds. It is likely that a combination of missing intake and suboptimal biomarkers were the cause for this under-prediction. Because of this, further studies regarding human metabolism should be performed for OPEs and potentially more specific biomarkers identified in the future. For PEs, there is a need for more comprehensive datasets to study exposure for high risk groups such as infants and children. Furthermore, dermal uptake remains poorly understood and the uptake of PEs into human nails should be studied in more detail to establish the kinetic links between exposure and body burden.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 4: Manuscript.
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Thor, Larsen Søren. "Adjuvant effect of phthalates and monophthalates in a murine injection model /." Cph. : Department of Pharmacology, Royal Danish School of Pharmacy and Department of Chemical Working environments, National Institute of Occupational Health, 2002. http://www.dfh.dk/phd/defences/Soeren%20Thor%20Larsen.html.
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Jobling, Matthew S. "Fetal germ cell development in the rat testis and the impact of di (n-Butyl) phthalate exposure." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4803.
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During gonad development and fetal life, the germ cells (GC) undergo a range of different developmental processes necessary for correct postnatal gametogenesis and the production of the next generation. If these fetal events are disrupted by genetic or environmental factors, there could be severe consequences that may not present until adulthood. This is of particular importance in relation to human testicular GC tumours (TGCT), the most common cancer of young men, as TGCT is thought to arise from fetal GCs that have failed to differentiate normally during development and thus persist into adulthood, eventually becoming tumourigenic. TGCT is one of several related disorders of male reproductive health thought to comprise a Testicular Dysgenesis Syndrome (TDS), in which faulty testis development in fetal life may predispose to the development of cryptorchidism, hypospadias, reduced sperm count and TGCT. Currently there is no accepted animal model for TGCT, but some insight into human TDS has been gained through the use of a rat model using in utero Di (n-Butyl) Phthalate (DBP) exposure to induce cryptorchidism, hypospadias, low sperm count and reduced fertility (but not TGCT). However, a previous study suggested that DBP exposure can disrupt GC differentiation, resulting in significantly reduced GC number prior to birth and postnatal consequences. This thesis has been directed at investigating the normal process of GC development in the fetal rat and how this is altered by DBP exposure; such understanding may give insights into the origins of human TGCT by showing how and when disruption of normal fetal GC differentiation can occur. The first objective was to characterise GC development in both the rat testis and ovary to understand the normal events that occur between embryonic day (e)13.5 and e21.5, as most data in the literature is based on the mouse. Analysis by immunohistochemical, stereological and mRNA expression indentified that during this time period, a GC will undergo a dynamic sequence of changes involving migration, proliferation followed by differentiation (manifested by loss of specific protein markers), whilst undergoing germ-line specific remethylation. Whilst whole gonad development is vastly different between testes and ovaries, GC development was broadly the same with only minor differences up to the point where GCs in the ovary enter meiosis. Having established the normal process of GC development in the fetal rat testis, the effects of in utero DBP exposure was then investigated. DBP exposure reduced GC number at all ages investigated even after only 24 hours of exposure and simultaneously prolonged GC proliferation. As apoptosis was unaltered by DBP exposure, the consistent reduction in GC number was suggested to be due to an initial reduction in GC number that does not recover to control levels. GC differentiation was assessed by the expression and localization of specific protein markers (OCT4, DMRT1 and DAZL). The pattern of expression of OCT4 and DMRT1 was altered by DBP exposure. GCs in DBP exposed animals also showed a delay in disaggregation from within the centre of seminiferous cords. These results suggested that a delay in GC differentiation was occurring with DBP exposure. This delay in GC development persisted into early postnatal life, following cessation of DBP exposure. Thus at postnatal day (D)6, GC specific re-expression of DMRT1, GC migration to the basal lamina and resumption of GC proliferation all showed a delay. DBP also induced an increase in the presence of multinucleated gonocytes. DNA methylation in the fetal rat testis was also investigated as a mechanism that could be disrupted by DBP exposure. DNA methylation of GCs increased during the last week of fetal life by global methylation of the GC genome and the increased expression of DNA methyl transferases. No effect of DBP exposure was detected. Inhibition of methylation by 5-aza-2’deoxycytidine was then investigated as a way to block GC differentiation in fetal rat testes and this resulted in a similar transient delay in GC differentiation but was perinatally lethal to the fetus. Bisulphite sequencing of the OCT4 promoter was also performed but proved inconclusive. Methylation patterns may be being altered by DBP exposure, but such changes could not be identified in this thesis. To complement the in vivo DBP exposure studies, an in vitro testis explant system using e14.5 testes was investigated. These in vitro testis explants showed some GC effects with MBP, the active metabolite of DBP, and also suggested a novel role for Hedgehog signalling in GC survival in the fetal rat testis. The studies in this thesis have characterised several aspects of fetal GC development in the rat and identified which of these are affected by DBP exposure, resulting in a delay in GC development. As DBP exposure delays but does not block GC differentiation, this may explain why TGCT is not induced in the DBP exposure rat model for TDS.
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Roos, Anna. "The importance of diet for uptake of phthalates in pregnant women." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-56675.
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McCormack, Daniel. "The Associations Between Bisphenol A and Phthalates, and Measures of Adiposity Among Canadians." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34349.
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Bisphenol A (BPA) and phthalates are chemicals found in many consumer products including water bottles, food packaging and cosmetics. Previous research has shown that there is potential for these compounds to contribute to obesity. In this analysis, the Canadian Health Measures Survey was used to investigate possible associations between urinary concentrations of these compounds and measures of adiposity. BPA urine concentrations were found to decrease with age, and significant associations with BMI and waist circumference were found in linear regression in adults. No associations with measures of adiposity were found in logistic regression for adults and significant negative associations were found in children. A similar discrepancy was found for mono-(2-ethyl-5-hydroxyhexyl) phthalate and mono-(2-ethyl-5-oxohexyl) phthalate, which were significantly associated with obesity in adults, but showed several significant negative associations in children. Overall, this analysis showed that it is unlikely that BPA and phthalates are contributing to adiposity in the Canadian population.
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Al-Qazzaz, Anas L. "A kinetic study of the radiolytic degradation of phthalates in aqueous solutions." Thesis, California State University, Long Beach, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1527353.
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Phthalates have attained a great deal of attention recently due to their reported association with endocrine system disturbances. Currently, advanced oxidation processes (AO/RPs) are being considered for use in remediating these chemical contaminants from anthropogenic waste waters; however, there is little known about the kinetics of AO/RP radical reactions with phthalates in water. In this work we investigated the reaction kinetics of the hydroxyl radical, hydrated electron and sulfate radical with a series of phthalates and phthalate monoester metabolites using electron pulse radiolysis. A direct relationship was found between the molecular complexity of the phthalate esters and the natural logarithm of their corresponding hydroxyl radical rate constant. Phthalate monoester metabolites were found to have higher rate constants than the corresponding phthalate diesters of similar molecular complexity. No structural relationship was found between phthalate esters and their corresponding hydrated electron rate constant.
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Gascon, Merlos Mireia 1984. "Persistent organic pollutants, bisphenol A, phthalates and respiratory and immune health in childhood." Doctoral thesis, Universitat Pompeu Fabra, 2014. http://hdl.handle.net/10803/145922.
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Persistent organic pollutants (POPs), bisphenol A (BPA) and pthalates may increase the risk of respiratory infections and allergic diseases in infants and the effects might last until, at least, adolescence. Cytokines and biomarkers of inflammation can provide information of the mechanisms behind such associations. Data from the “Infancia y Medioambiente” (INMA) population-based birth cohort project and from six other existing European birth cohort studies have been used in the present thesis, which also includes a systematic review. Results of the present work, which includes five scientific publications, suggest that prenatal exposure to POPs affects the immune and respiratory health of children, that the effects are observed even at low levels of exposure and that these may last until adolescence. Biological mechanisms behind such effects were not possible to describe in the present thesis, however, it provided information of a potential biomarker (interleukin 10) of chronic immunotoxic effects of POPs. Results also indicate potential effects of prenatal exposure to BPA and phthalates on the development and functioning of the immune and respiratory systems of infants and children. In the present thesis we highlight the limitations of existing studies in the field and provide recommendations for future research.Els compostos orgànics persistents (COPs), el bisfenol A (BPA) i els ftalats podrien estar relacionats amb un increment del risc de patir infeccions respiratòries i símptomes relacionats amb l’al•lèrgia en infants i fins, com a mínim, l’adolescència. Les citoquines i els marcadors d’inflamació poden aportar informació dels mecanismes que hi ha darrera d’aquestes associacions. En la present tesis s’han utilitzat dades de la cohort de naixement “Infancia y Medioambiente” (INMA) i de sis cohorts de naixement Europees. La tesis també inclou una revisió sistemàtica. Els resultats d’aquest treball, que inclou cinc publicacions científiques, suggereixen que l’exposició prenatal a COPs afecta els sistemes immunitari i respiratori dels infants i nens, que aquests efectes es donen inclús a exposicions relativament baixes i que aquests efectes poden perdurar fins a l’adolescència. Els mecanismes biològics que podrien explicar els efectes observats no s’han pogut descriure en el present treball, tot i així, hem aportat informació d’un possible biomarcador (interleuquina 10) dels efectes immunotòxics crònics dels COPs. Els resultats també mostren efectes potencials de l’exposició prenatal a BPA i ftalats sobre el desenvolupament i funcionament dels sistemes immunitari i respiratori dels infants i nens. A la present tesis es remarquen les principals limitacions dels estudis existents en aquest camp i es proposen recomanacions de millora per a futurs estudis. Mentrestant, es recomana revisar la legislació actual per tal de reduir l'ús d'aquells compostos que encara estan al mercat i que s'utilitzen àmpliament.
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Shu, Huan. "Phthalates : On the issue of sources, human uptake, time trends and health effects." Doctoral thesis, Karlstads universitet, Institutionen för hälsovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-62637.
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Human health depends on a well-functioning endocrine system to regulate hormone release for normal bodily functions. Endocrine disrupting chemicals (EDCs) constitutes a group of chemicals, included in many commonly used products, (e.g., PVC flooring), with properties proven or suspected to interact with the natural hormone system in humans and animals. EDCs are manmade compounds (there are also natural compounds with such properties) that can bind to cell receptors and mimic or block the functions of natural hormones potentially resulting in adverse human health effects. One type of widely concerning EDC is phthalates. Since phthalates create weak chemical bonds when they are added into different products, they readily leach into the surrounding environment. Phthalate metabolites can therefore be frequently measured in human biological samples. Major public health concerns regarding EDCs over the past three decades have focused on phthalates. According to the World Health Organization, EDCs are suspected to be associated with altered reproductive function in males and females, increased incidence of breast cancer, abnormal growth patterns and neurodevelopmental delays in children, as well as changes in immune function. The thesis shows that PVC flooring in the home is a source for human uptake of phthalates, that replacement of phthalates in soft PVC products have an impact on human uptake of these chemicals, and that exposure for phthalates in early life increase the risk for airway disorders in children. As we have shown, ongoing regulations on phthalates is of importance for human uptake. Ultimately, individuals can make small changes in their consumer product choices that can lead to changes in uptake of chemicals with endocrine disrupting properties. Philosophically, we all have a responsibility to protect future generations from dangerous chemicals.Human health depends on a well-functioning endocrine system to regulate hormone release for normal bodily functions. Endocrine disrupting chemicals (EDCs) constitutes a group of chemicals, included in many commonly used products, (e.g., PVC flooring), with properties proven or suspected to interact with the natural hormone system in humans and animals. One type of widely concerning EDC is phthalates. Since phthalates create weak chemical bonds when they are added into different products, they readily leach into the surrounding environment. Phthalate metabolites can therefore be frequently measured in human biological samples. Major public health concerns regarding EDCs over the past three decades have focused on phthalates resulting in implementation of regulations. The thesis shows that PVC flooring in the home is a source for human uptake of phthalates, that replacement of phthalates in soft PVC products have an impact on human uptake of these chemicals, and that exposure for phthalates in early life increase the risk for airway disorders in children. This means that regulation and consumers’ product choices can lead to changes in uptake of EDCs of importance for human health. Philosophically, we all have a responsibility to protect future generations from dangerous chemicals.
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Sen, Sumitra. "Cellular and Molecular Effects of Mono-(2-ethylhexyl) phthalate (MEHP) in Testicular Cancer." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36844.
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Phthalates are endocrine-disrupting chemicals (EDCs) that are known testicular toxicants, used commonly as industrial plasticizers that are found in everyday items. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundant phthalate in the environment, and its primary metabolite mono-(2-ethylhexyl) phthalate (MEHP) is ten-fold more potent. The purpose of this study is to examine the cellular and molecular effects of MEHP in the development of testicular cancer. Proliferation was measured for NT2 cells exposed to 10µM and 100µM MEHP at 24 and 48 hours and for cells under controlled conditions. Methylation-specific PCR (MSP) was used to determine the methylation status of the promoter region of key testicular genes post exposure to MEHP. MEHP caused a dose-dependent negative effect on proliferation and significantly altered methylation levels for key testicular genes following exposure to 10µM MEHP and 100µM, as compared to controls. This suggests that MEHP alters proliferation and methylation of testicular tumour cells in a time- and dose-dependent manner.
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Go, Jennifer. "Investigations Into the Effects of Gestational Exposure to Environmental Phthalates on Maternal and Perinatal Outcomes and the Role of Inflammation Biomarkers as Potential Mediators." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36925.
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Objectives The aims of this thesis were to (1) investigate the association of gestational exposure to environmental phthalates with maternal and perinatal outcomes, and (2) explore phthalate-induced changes to maternal inflammatory responses as potential mediators of possible health effects.
Methods A systematic review was performed to summarize existing evidence on the association of gestational exposure to phthalates with obstetrical outcomes, including pre-eclampsia (PE), pregnancy-induced hypertension (PIH), gestational diabetes mellitus (GDM), intrauterine growth restriction (IUGR), birth weight (BW), head circumference (HC), gestational age (GA), preterm birth (PB), and Apgar scores (AS). Additionally, a secondary analysis of data from the MIREC Study was conducted to evaluate the association of phthalate metabolites with clinical outcomes in the mother and infant using multiple linear and logistic regression, and with inflammatory biomarkers using multinomial logistic regression.
Results The systematic review identified a total of 24 articles, and observed inconsistent evidence on BW, HC, GA, and PB, a paucity of research on IUGR, PE, GDM, and AS, and a lack of studies on PIH. However, among studies with statistically significant (p<0.05) results, most suggest an association of phthalates with decreased BW and GA, and increased HC and PB. Findings from the MIREC Study indicate a significant (p<0.01) positive association between MBP and HC among female infants; however, null results were identified for BW, GA, PB, AS, and PIH. In relation to the exposure to phthalates, general trends among suggestive associations (p<0.05) for head circumference showed consistent increases in females and decreases in males, and for gestational age displayed decreases in both stratums. Additionally, a significant positive association of MBzP and ∑DEHP was observed with high MMP-2 and low VCAM levels, respectively. Results approaching statistical significance demonstrated a positive association of ∑DEHP with low MCP1 and ICAM levels, MCPP with low GMCSF levels, MBzP with low CRP and high ICAM levels, and MEP with high MMP-7 and IL-2 levels.
Conclusion From the systematic review, the effects of phthalates on maternal and perinatal health remain unclear, possibly due to sources of heterogeneity and challenges in exposure assessment. In the MIREC Study cohort, phthalate levels were associated with GA and HC in infants in a sex-specific manner. Phthalates also appear to influence the circulating inflammatory marker levels, possibly explaining the observed adverse effects. Future research is needed to validate these findings.
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Riesgo, Victoria Rae. "Phthalate Exposure and Maternal Infection: Implications for Neurodevelopment." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1619553601242514.
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Kissel, Hannah J. "Urinary Phthalates as Potential Biomarkers for Attention Deficit Disorder and Proposed Dopaminergic Pathway Interactions." University of Toledo Honors Theses / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=uthonors1533402644802545.
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Jonsson, Susanne. "Phthalates in landfill leachates : a signature of their degradation : analytical aspects & toxicological considerations /." Linköping : Univ, 2003. http://www.bibl.liu.se/liupubl/disp/disp2003/arts268s.pdf.
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Anderson, Warwick Alistair Christian. "Development and application of a biomarker method to quantify human dietary exposure to phthalates." Thesis, University of Sunderland, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250739.
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Gunnarsson, David. "Reproductive toxicology of endocrine disruptors : effects of cadmium, phthalates and phytoestrogens on testicular steroidogenesis." Doctoral thesis, Umeå : Department of Molecular Biology, Umeå University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1876.
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Aoki, Katherine A. "A study of the anti-androgenic effects of the phthalate ester, din-butyl phthalate, on two freshwater fish species, the fathead minnow and the three-spined stickleback." Thesis, Brunel University, 2010. http://bura.brunel.ac.uk/handle/2438/4408.
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For the past few years there has been increasing concern surrounding a group of chemicals known as phthalate esters. In mammals, phthalates are known antiandrogens, interfering with the production or activity of testosterone. Phthalates are ubiquitous in the aquatic environment. With recent findings suggesting that antiandrogens may be responsible for much of the endocrine disruption found in wild fish populations, the study of phthalate esters has become integral to determining whether or not these anti-androgenic chemicals are of concern. I investigated whether di-n-butyl phthalate (DBP) was able to cause antiandrogenic endocrine disruption in fish under controlled laboratory conditions. Three experiments were undertaken. In the first study, two generations of fathead minnows were exposed to nominal concentrations of 6 to 100 μg/L for 21 and 150 days, respectively. The second experiment examined the effects of early life-stage exposure to DBP (50, 100 and 200 μg DBP/L) on three-spined sticklebacks. The final experiment examined the effects of DBP on adult male three-spined sticklebacks in a 21-day nesting study (15 and 35 μg DBP/L). DBP had no effect on the fecundity, survival, growth, sex ratio, or gonadal histology of the exposed fish in any of the experiments. Further, it failed to alter the expression of two steroidogenic genes in adult male sticklebacks. In contrast, DBP was often found to significantly alter plasma androgen concentrations in both species, and spiggin concentrations in the three-spined stickleback, most notably causing significantly reduced spiggin concentrations in the adult males exposed to DBP. Ultimately, DBP-exposure did not disrupt the ability of the fish to reproduce successfully, and did not appear to alter reproductive behaviours or the expression of secondary sexual characteristics. In conclusion, while DBP did appear to have some capacity for endocrine disruption in fish, it was unable to interfere with the ability of the fish to develop normally and reproduce successfully. Thus, environmentallyrelevant concentrations of phthalate esters are likely not of particular concern to fish populations.
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Schoen, Stephanie. "Individual and Cumulative Effects of a Mixture of Phthalates and Children's Intellectual Abilities: A Secondary Analysis of Data from the MIREC Study." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42674.
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Phthalates, chemicals found in a variety of consumer goods and personal care products, may adversely affect fetal neurodevelopment. Women are exposed to a mixture of phthalates during pregnancy because of the common presence of these chemicals in consumer goods. The aim of this study is to investigate potential associations between phthalate exposure during the first trimester of gestation and Intelligence Quotient (IQ) scores of 3-year old children.
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Bergh, Caroline. "Organophosphates and phthalates in air and dust from indoor environments : Method development and applied measurements." Doctoral thesis, Stockholms universitet, Institutionen för analytisk kemi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-56677.
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Organophosphate and phthalate esters are polymer additives that are frequently found in air and dust in indoor environments. This thesis describes the development and application of air sampling and selective mass spectrometric (MS) determination of these two compound groups. It also describes the sampling and screening of these compounds in indoor air and dust from different environments and the development and evaluation of a method for the extraction and determination of these compounds in indoor dust. An air sampling method previously used for air sampling of only organophosphate esters, is here demonstrated to be applicable for simultaneous sampling of both phthalate and organophosphate esters. Selective detection using tandem mass spectrometry (MS/MS) showed good results for simultaneous determination of organophosphate and phthalate esters in air. The high selectivity of this technique was especially advantageous when analyzing dust. Comparison of chemical profiles of the organophosphate ester between indoor environments including daycare centers, offices and private homes differed between the types of locations while the phthalate profiles were rather similar. Comparison of concentration levels of these compounds in multi-storey apartment buildings classified as either high or low risk “sick” buildings could not differentiate the two classes of buildings. Further, the studies also points out some potential sources of organophosphate and phthalate esters in these indoor environments. In general the levels of phthalate esters were consistently higher than the levels of organophosphate esters both in air and in dust. Phthalate and organophosphate esters were also determined in a dust standard reference material; seventeen of the targeted compounds were quantified out of which ten had not previously been reported for this reference material.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.
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Lovchik, Martin Alan. "TRANSITION METAL CATALYZED REARRANGEMENT OF DIMETHYL VINYLCYCLOBUTENE DICARBOXYLATES DERIVATIVES TO DIMETHYL CYCLOHEXADIENE DICARBOXYLATES AND PHTHALATES." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1000127850.
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Ganeshakumar, Mathumai. "Chronic toxicity of phthalates, biphenol and a Canadian bottled water stored under different light regimes using the Cnidarian Hydra Viridissima©." Thesis, UOIT, 2009. http://hdl.handle.net/10155/38.
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There is general concern whether human exposure to selected Canadian bottled
waters and the chemicals which may leach from them, could potentially cause deleterious
effects. This research was designed to determine whether exposures to bottled water and
plastic leachates caused toxicity to the freshwater Cnidarian Hydra viridissima (green
hydra). Three chemicals used in the production of polycarbonate and polyethylene
plastics, bisphenol A (BPA) and two phthalate esters: dibutyl phthalate (DBP) and bis (2-
ethylhexyl) phthalate (DEHP) along with one type of commercial bottled water were
investigated. One brand of bottled water was analyzed over four months (stored in light
and dark conditions) along with lab water similarly stored in glass, polycarbonate and
polyethylene bottles. Following 2, 4, 8 and 16 weeks in each of the two treatments, hydra
bioassays were conducted. Chronic toxicity tests were also conducted on the two
phthalates and BPA. The chronic toxicity tests showed that BPA caused effects on hydra
morphology and population at low doses and DBP and DEHP both showed signs of
hormesis.
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SCAPIN, VALDIRENE de O. "Avaliacao da contaminacao por elementos inorganicos e esteres ftalicos em poeira domestica da regiao metropolitana de Sao Paulo." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9495.
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Made available in DSpace on 2014-10-09T12:27:18Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T13:59:13Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Norman, Belinda. "Giftfria förskolor i Nordmalings kommun : En inventering av förskolor med åtgärdsförslag för att möjliggöra en minskning av barns negativa hälsoeffekter till följd av kemikalieexponering." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-123219.
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Humans are exposed to chemicals every day in our indoor environment. Chemicals have contributed to increased prosperity but also caused negative health effects. Children are vulnerable to chemicals because of their development and they breathe and drink more in relation to their body weight. That is why it’s important to reduce chemical exposure in environment for children. Preschools have a central role when it comes to materials and products that may pose a risk for exposure. The municipality has an important role to achieve a nontoxic environment which is based on a Swedish environmental quality goal (Non-toxic environment). This study is a part of the prioritized local environmental work in the municipal of Nordmaling. An inventory has been done to find out what type of chemicals that may expose children to harmful effects in preschools of Nordmaling. Electronic as a toy, soft and smelling toys, plastic around food and drinks, foam play pads were common products found during the inventory. This materials containing phthalates, brominated flame retardants, perfluorinated compounds, bisphenol A, lead and cadmium that can expose children through leaching into the indoor environment. A guidance have been constructed to achieve a non-toxic environment based on the results from the inventory in a cost effective way. The conclusion of the report is clear, identified problem areas can quickly be accomplished with small measures and low costs. Increased awareness of harmful substances and good routines for purchases and cleaning can further reduce the exposure to chemicals in the preschools.
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LOUREIRO, ISABELLA RODRIGUES. "THE IMPORTANCE AND OCCURRENCE OF PHTHALATES IN POTABLE WATERS AND SAMPLES FROM THE GUANABARA BAY ECOSYSTEM." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=3654@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFtalatos são os plastificantes mais utilizados industrialmente, estando disseminados em todos os ecossistemas do mundo. Como são compostos exclusivamente sintéticos, sua presença é indicativa da industrialização de uma região. Sua toxicidade é baixa, porém existem indícios de possíveis efeitos como interferentes endócrinos, especialmente no sistema reprodutor masculino. No Brasil, existem poucos estudos sobre a ocorrência e comportamento dos ftalatos no meio ambiente. Nesta tese foi estudada sua ocorrência em amostras de águas potáveis de diversos bairros das cidades do Rio de Janeiro e Niterói e do ecossistema da Baía de Guanabara (águas, sedimentos e mexilhões), a qual recebe inúmeros aportes industriais. Todas as amostras foram coletadas, extraídas em fase sólida e analisadas por cromatografia em fase gasosa, utilizando detecção por captura de elétrons. As da Baía foram amostradas nas estações seca e chuvosa, em diferentes anos. As extrações de todas as amostras obtiveram excelente repetibilidade e recuperações superiores a 76%. As águas potáveis do Rio de Janeiro e Niterói apresentaram teores de ftalatos em concentrações muito menores do que as informadas para cidades da Europa e Estados Unidos. Tais teores puderam ser correlacionados com as extensões das redes dos sistemas de abastecimento de ambas as cidades. Todas as amostras da Baía mostraram contaminações qualiquantitativas muito inferiores, quando comparadas a outros ambientes costeiros. O estudo do biomonitoramento ativo evidenciou a eficiência e rapidez da depuração dos ftalatos nos mexilhões mais contaminados do ecossistema da Baía de Guanabara.
Phthalates are the most used plasticizers in industrial products, worldwide distributed in environments. Their presence is often used to indicate a region industrialization degree. Although their reported toxicity is low, phthalates are indicated for possible endocrine disrupting effects, specially in male reproductive system. In Brazil, there are few studies about the environmental occurrence and distribution of phthalates. This thesis studied the occurrence of those compounds in potable waters samples from residential areas of Rio de Janeiro and Niterói cities, and in samples from the ecosystem of Guanabara Bay (waters, sediments and mussels), which receives several industrial inputs. All the samples were collected, solid-phase extracted and the phthalate contents analyzed by gas chromatography with electron capture detection. The ones from the Bay were sampled during the dry and rainy seasons, in different years. All the extractions presented excellent repeatability and recoveries above 76%. The potable water samples from both cities presented phthalate values considerably lower than those reported for European and American cities. The results could be correlated with the water net distribution lengths for both cities. All results from the Bay ecosystem showed lower contamination when compared to other coastal environments. The controlled transplant proved quick and efficient phthalate depuration of contaminated organisms from Guanabara Bay.
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Xu, Ying. "Emissions of Phthalate Plasticizer from Polymeric Building Materials." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/37913.
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Modern indoor environments contain a vast array of contaminating sources. Emissions from these sources produce contaminant concentrations that are substantially higher indoors than outside. Because we spend most of our time indoors, exposure to indoor pollutants may be orders-of-magnitude greater than that experienced outdoors. Phthalate esters have been recognized as major indoor pollutants. They are mainly used as plasticizers to enhance the flexibility of polyvinylchloride (PVC) products, as well as in humectants, emollients, and antifoaming agents. Phthalates are found in a wide range of consumer products including floor and wall coverings, car interior trim, floor tiles, gloves, footwear, insulation on wiring, and artificial leather. Because these phthalate additives are not chemically bound to the polymer matrix, slow emission from the products to the surrounding air or other media usually occurs.
Biomonitoring data suggest that over 75% of the U.S. population is exposed to phthalates. The ubiquitous exposure to phthalates is of concern because toxicological investigations have demonstrated considerable adverse health effects of phthalates and their metabolites. Studies have shown that exposure to phthalates results in profound and irreversible changes in the development of the reproductive tract, especially in males, raising the possibility that phthalate exposures could be the leading cause of reproductive disorders in humans. In addition, effects such as increases in prenatal mortality, reduced growth and birth weight, skeletal, visceral, and external malformations are possibly associated with phthalate exposure. Epidemiologic studies in children also show associations between phthalate exposure in the home and the risk of asthma and allergies.
Given the ubiquitous nature of phthalates in the environment and the potential for adverse human health impacts, there is a critical need to understand indoor emissions of phthalates and to identify the most important sources and pathways of exposure.
In this study, a model that integrates the fundamental mechanisms governing emissions of semi-volatile organic compounds (SVOCs) from polymeric materials and their subsequent interaction with indoor surfaces and airborne particles was developed. The emissions model is consistent with analogous mechanistic models that predict emission of volatile organic compounds (VOCs) from building materials. Reasonable agreement between model predictions and gas-phase di-2-ethylhexyl phthalate (DEHP) concentrations was achieved for data collected in a previously published experimental study that measured emissions of DEHP from vinyl flooring in two very different chambers. The analysis showed that while emissions of highly volatile VOCs are subject to “internal“ control (through the material-phase diffusion coefficient), emissions of the very low volatility SVOCs are subject to “external“– control (through partitioning into the gas phase, the convective mass transfer coefficient, and adsorption onto interior surfaces).
Because of the difficulties associated with sampling and analysis of SVOCs, only a few chamber studies quantifying their emissions from building materials and consumer products are available. To more rigorously validate the SVOCs emission model and more completely understand the mechanisms governing the release of phthalate from polymeric building materials, the emission of DEHP from vinyl flooring was studied for up to 140 days in a specially-designed stainless steel chamber. In the duplicate chamber study, the gas-phase concentration in the chamber increased slowly and reached a steady state level of 0.9 µg/m3 after 30 days. By increasing the area of vinyl flooring and decreasing that of the stainless steel surface in the chamber, the time to reach steady state was significantly reduced, compared to the previous study (1 month vs. 5 months). The adsorption isotherm of DEHP on the interior stainless steel chamber surface was explicitly measured using two different methods (solvent extraction and thermal desorption). Strong adsorption of DEHP onto the stainless steel surface was observed and found to follow a simple linear relationship. In addition, parameters measured in the experiments were then applied in the fundamental SVOCs emission model. Good agreement was obtained between the predictions of the model and the gas-phase DEHP chamber concentrations, without resorting to fitting of model parameters.
These chamber studies have shown that the tendency of SVOCs to adsorb strongly to interior surfaces has a very strong influence on the emission rate. Compared to the experimental chamber systems, however, the real indoor environment has many other types of surface that will adsorb phthalates to different extents. The emission rate measured in a test chamber may therefore be quite different to the emission rate from the same material in the indoor environment. For this reason, both a two-room model and a more representative three-compartment model were developed successively to estimate the emission rate of DEHP from vinyl flooring, the evolving gas-phase and adsorbed surface concentrations, and human exposures (via inhalation, dermal absorption and oral ingestion of dust) in a realistic indoor environment. Adsorption isotherms for phthalates and plasticizers on interior surfaces, such as carpet, wood, dust and human skin, were derived from previous field and laboratory studies. A subsequent sensitivity analysis revealed that the vinyl flooring source characteristics, as well as mass-transfer coefficients and ventilation rates, are important variables influencing the steady-state DEHP concentration and resulting exposures. A simple uncertainty analysis suggested that residential exposure to DEHP originating from vinyl flooring may fall somewhere between about 5 µg/kg/d and 180 µg/kg/d. The roughly 40-fold range in exposure reveals the inherent difficulty in using biomonitoring results to identify specific sources of exposure in the general population.
This research represents the first attempt to explicitly elucidate the fundamental mechanisms governing the release of phthalates from polymeric building materials as well as their subsequent interaction with interior surfaces. The mechanistic models developed can most likely be extended to predict concentration and exposure arising from other sources of phthalates, other sources of other semi-volatile organic compounds (such as biocides and flame retardants), as well as emissions into other environmental media (food, water, saliva, and even blood). The results will be of value to architects, governments, manufacturers, and engineers who wish to specify low-emitting green materials for healthy buildings. It will permit health professionals to identify and control health risks associated with many of the SVOCs used in indoor materials and consumer products in a relatively inexpensive way.Ph. D.
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Schripp, Tobias [Verfasser], and K. U. [Akademischer Betreuer] Gericke. "Distribution of phthalates in the indoor environment – Application and evaluation of indoor air models – / Tobias Schripp ; Betreuer: K.U. Gericke." Braunschweig : Technische Universität Braunschweig, 2009. http://d-nb.info/1175829900/34.
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Ezem, Gladys Chidiebere. "Relationship Between Exposure to Phthalate and Obesity in the United States." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5855.
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Obesity is a public health problem. The global obesity problem has been attributed to unhealthy diet, inactivity, and hereditary factors. However, phthalates may also contribute to the obesity epidemic. The purpose of this cross-sectional study was to examine whether there was a relationship between exposure to phthalates and obesity among adults 18 years and older in the United States. The theoretical framework was based on the socioecological model. The quantitative, cross-sectional design, and data analysis were based on the National Health and Nutrition Examination Survey, 2011-2012 database. Descriptive statistics and multiple regression analysis were used to analyze the association between phthalates, obesity, and other independent variables (phthalates exposure, socioeconomic status, gender, age, race/ethnicity, physical activity and place of residence) According to study results, exposure to phthalates does not have a statistically significant effect on the odds of obesity. In terms of the influence of the sociodemographic variables such as race, age, and gender on the relationship between total phthalate exposure and obesity, only race showed statistical significance at p < 0.05. In addition, physical activity did not have influence on relationship between total phthalate exposure and obesity among adults 18 years and older in the United States. Despite the lack of significant relationships, the results of this study are useful in addressing the concerns about the exacerbation of obesity. The results of this study could enhance academic research by showing the effect of phthalate chemical exposure, age, gender, race/ethnicity, physical activity, income, and educational level on obesity.
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Bountis, Stavros. "Effects of a phthalate mixture on Wnt/β-catenin signaling, apoptosis and metabolic rate in zebrafish embryos." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-415065.
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One of the most common plasticizers used in the production of plastic are phthalates. These chemicals have been associated with many adverse effects including developmental and reproductive anomalies. Early developmental processes targeted by chemicals can have long-lasting effects on individuals. The focus of this study was on investigating the effects of a phthalate monoester mixture on two evolutionarily conserved processes, Wnt/β-catenin signaling and apoptosis, both of which play an important role during development. Focus was also given on the mixture’s effect in metabolic rate. The phthalate mixture used is part of mixture G, a mixture which additionally contains triclosan and three perfluoroalkyl acids. The components of Mixture G were identified in a Swedish pregnancy cohort (SELMA) and were inversely associated with birth weight. The experiments were conducted in zebrafish embryos. Wnt signaling was analyzed in a transgenic zebrafish line, which had the EGFP gene linked to β-catenin regulated promoters, by measuring the fluorescence in the caudal fin. Apoptosis was analyzed through the acridine orange assay and metabolic rate through the transformation of resazurin to resorufin in presence of NADH/NADPH. The results showed a downregulation of Wnt signaling in zebrafish at two days post-fertilization (2 dpf), at a water concentration 100 times higher than the geometric mean serum concentration (100x hsc) of the mothers in the SELMA cohort. An upregulation of apoptosis was found at 1 dpf, at 60x hsc and 100x hsc. An effect on metabolic rate was observed at 100x hsc at 5 dpf. The results indicate that phthalates can disrupt Wnt signaling, induce apoptosis and influence metabolic rate, which along with the various reproductive effects they can induce warrants cause for concern not only for zebrafish embryos but for human fetuses as well.
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Paluselli, Andrea. "Analysis, occurence, release and degradation of phthalate esters (PAEs) in Mediterranean coastal sea." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0060/document.
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Les phtalates (PAEs) sont un groupe de contaminants organiques émergents qui sont devenus une préoccupation majeure en raison de leur omniprésence dans le milieu marin et de leurs effets perturbateurs sur le système endocrinien. Cependant, leur répartition en Méditerranée est assez mal connue, principalement en raison des difficultés analytiques et du risque élevé de contamination des échantillons lors du processus analytique. En outre, les débris de plastique en milieu marin contiennent des additifs comme les PAEs, qui sont ajoutés lors de l’étape de fabrication du plastique. Dans la première partie de cette thèse, une méthode analytique a été optimisée et validée pour la détermination de 8 PAEs à l'état de traces en milieu marin. Brièvement, 1L d'échantillon filtré est passé à travers des cartouches de verre contenant 200 mg d'Oasis HLB, puis élué à l’aide de 6mL d'acétate d'éthyle. Notre méthode donne des rendements d’extraction compris entre 95 et 115 % et des blancs acceptables. Dans un second temps, un suivi annuel de la contamination de la Baie de Marseille a été effectué de décembre 2013 à novembre 2014. Les résultats ont montré la présence de 7 PAEs, avec des concentrations totales variant de 130 à 1330 ng L-1. Dans la dernière partie de cette thèse, deux échantillons de plastique communs (sac de poubelle et gaine de câble électrique) ont été incubés dans de l'eau de mer naturelle dans des conditions contrôlées de laboratoire, de manière à évaluer la migration de PAEs depuis ces matériaux en fonction de différentes conditions environnementales comme la température, la présence de lumière, ou encore la présence de bactériesPhthalic Acid Esters (PAEs) are a group of emerging organic contaminants that have become a serious issue because of their ubiquitous presence on the marine environment worldwide and for the endocrine disrupting effects in animals and humans. However, little is known about their distribution in the Ocean, mainly because of analytical difficulties and the high possibility of ambient sample contamination. Plastic debris in marine environment includes resin pellets, macro- and microplastic fragments, and contains additives such as PAEs that might be released in the aquatic environment in unknown proportion. In our work, we improved an analytical method for the determination of 8 PAEs, at trace levels in marine and fresh waters. In the first part of the thesis, the method was validated for different seawater salinities and wastewater treatment plant outlet. By passing 1 L of sample through glass cartridges packed with 200 mg of Oasis HLB and eluted with 6 mL of ethyl acetate, the recoveries of 8 PAEs ranged from 95 to 115 % with acceptable blank values (below 0.4-4.0 % of the masses measured in different seawater samples). In a second part, PAE distribution in the Marseille Bay has been evaluated though a one-year monitoring from December 2013 to November 2014. The results showed the occurrence of six PAEs with total concentrations ranging from 130 to 1330 ng L-1. In the last part of this thesis, two common plastic samples as trash plastic bags and insulation layer of electric cables were incubated in natural seawater in laboratory conditions and studied for the release of PAE. Release ws observed for the different PAEs with kinetics varying according to the plastic type
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Paluselli, Andrea. "Analysis, occurence, release and degradation of phthalate esters (PAEs) in Mediterranean coastal sea." Electronic Thesis or Diss., Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0060.
Full textAbstract:
Les phtalates (PAEs) sont un groupe de contaminants organiques émergents qui sont devenus une préoccupation majeure en raison de leur omniprésence dans le milieu marin et de leurs effets perturbateurs sur le système endocrinien. Cependant, leur répartition en Méditerranée est assez mal connue, principalement en raison des difficultés analytiques et du risque élevé de contamination des échantillons lors du processus analytique. En outre, les débris de plastique en milieu marin contiennent des additifs comme les PAEs, qui sont ajoutés lors de l’étape de fabrication du plastique. Dans la première partie de cette thèse, une méthode analytique a été optimisée et validée pour la détermination de 8 PAEs à l'état de traces en milieu marin. Brièvement, 1L d'échantillon filtré est passé à travers des cartouches de verre contenant 200 mg d'Oasis HLB, puis élué à l’aide de 6mL d'acétate d'éthyle. Notre méthode donne des rendements d’extraction compris entre 95 et 115 % et des blancs acceptables. Dans un second temps, un suivi annuel de la contamination de la Baie de Marseille a été effectué de décembre 2013 à novembre 2014. Les résultats ont montré la présence de 7 PAEs, avec des concentrations totales variant de 130 à 1330 ng L-1. Dans la dernière partie de cette thèse, deux échantillons de plastique communs (sac de poubelle et gaine de câble électrique) ont été incubés dans de l'eau de mer naturelle dans des conditions contrôlées de laboratoire, de manière à évaluer la migration de PAEs depuis ces matériaux en fonction de différentes conditions environnementales comme la température, la présence de lumière, ou encore la présence de bactériesPhthalic Acid Esters (PAEs) are a group of emerging organic contaminants that have become a serious issue because of their ubiquitous presence on the marine environment worldwide and for the endocrine disrupting effects in animals and humans. However, little is known about their distribution in the Ocean, mainly because of analytical difficulties and the high possibility of ambient sample contamination. Plastic debris in marine environment includes resin pellets, macro- and microplastic fragments, and contains additives such as PAEs that might be released in the aquatic environment in unknown proportion. In our work, we improved an analytical method for the determination of 8 PAEs, at trace levels in marine and fresh waters. In the first part of the thesis, the method was validated for different seawater salinities and wastewater treatment plant outlet. By passing 1 L of sample through glass cartridges packed with 200 mg of Oasis HLB and eluted with 6 mL of ethyl acetate, the recoveries of 8 PAEs ranged from 95 to 115 % with acceptable blank values (below 0.4-4.0 % of the masses measured in different seawater samples). In a second part, PAE distribution in the Marseille Bay has been evaluated though a one-year monitoring from December 2013 to November 2014. The results showed the occurrence of six PAEs with total concentrations ranging from 130 to 1330 ng L-1. In the last part of this thesis, two common plastic samples as trash plastic bags and insulation layer of electric cables were incubated in natural seawater in laboratory conditions and studied for the release of PAE. Release ws observed for the different PAEs with kinetics varying according to the plastic type
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Omoike, Ogbebor Enaholo. "Association of Perfluorinated Chemicals with Endocrino-Carcinogenetic, Obesogenic and Metabolic Health and with Markers of Chronic Inflammation and Oxidative Stress." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/etd/3733.
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First, this study examined the association of perfluorinated chemicals with 1) cardio-metabolic health outcomes and 2) the association of phthalates with cardiometabolic health outcomes, and 3) cardio-metabolic health outcomes while assessing the possibility of additive interactions between perfluorinated chemicals (PFCs) and phthalates. Second, association with markers of chronic inflammation and oxidative stress were explored. Finally, this study examined the association of these chemicals with estrogenic cancers- Breast cancer, prostate cancer, uterine cancer and ovarian cancer.
Using data from the National Health and Nutrition Examination Survey (NHANES), logistic regression models were used to investigate the relationship between PFCs and the cardio-metabolic health outcomes adjusting for covariates. An interaction term between PFCs and phthalates was added to the main effect model to assess the possibility of effect modification. Generalized linear models were used to examine associations between PFCs and inflammatory and oxidative stress markers per unit increase in exposure to PFCs while adjusting for covariates. Binomial logistic regression was used in investigating the association between quartiles of PFCs and presence or absence of cancer while also adjusting for covariates. Discriminant analysis was used to assess the correlation between individual PFCs compounds and individual cancer categories.
Perfluorononanoic acid (PFNA) was associated with increased odds of central obesity in females, odds ratio (OR): 1.10; 95% confidence interval (CI): (1.01, 1.21). Perfluorohexane sulfonic acid (PFHS), Perfluorononanoic acid (PFNA), Perfluorooctanoic acid (PFOA), Perfluorooctane sulfonic acid (PFOS), and Perfluorodecanoic acid (PFDE) were all significantly associated with lymphocyte counts. Beta (95% CI); 0.03(0.02,0.05), 0.04(0.02,0.05), 0.05(0.03, 0.07), 0.04(0.03,0.05), 0.03(0.01,0.04) and with serum iron 0.07(0.05,0.09), 0.04(0.02,0.07), 0.10(0.07,0.12), 0.05(0.03,0.07), 0.04(0.02,0.06) and serum albumin 0.02(0.02,0.02), 0.02(0.02,0.03), 0.03(0.03,0.04), 0.02(0.02, 0.023), 0.01 (0.01, 0.05). Only PFHS, PFNA, PFOA and PFOS were associated with serum total bilirubin 0.04(0.03,0.05), 0.02(0.00,0.03), 0.06(0.04,0.08), 0.03(0.02,0.05). PFCs studied were associated with increased odds of breast, prostate, uterine and ovarian cancers, p
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Giovanoulis, Georgios. "What contributes to human body burdens of phthalate esters? : An experimental approach." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-143147.
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Phthalate esters (PEs) and alternative plasticizers used as additives in numerous consumer products are continuously released into the environment leading to subsequent human exposure. The ubiquitous presence and potential adverse health effects (e.g. endocrine disruption and reproductive toxicity) of some PEs are responsible for their bans or restrictions. This has led to increasing use of alternative plasticizers, especially cyclohexane-1,2-dicarboxylic acid diisononyl ester (DINCH). Human exposure data on alternative plasticizers are lacking and clear evidence for human exposure has previously only been found for di(2-ethylhexyl) terephthalate (DEHTP) and DINCH, with increasing trends in body burdens. In this thesis, a study population of 61 adults (age: 20–66; gender: 16 males and 45 females) living in the Oslo area (Norway) was studied for their exposure to plasticizers. Information on sociodemographic and lifestyle characteristics that potentially affect the concentrations of PE and DINCH metabolites in adults was collected by questionnaires. Using the human biomonitoring approach, we evaluated the internal exposure to PEs and DINCH by measuring concentrations of their metabolites in urine (where metabolism and excretion are well understood) and using these data to back-calculate daily intakes. Metabolite levels in finger nails were also determined. Since reference standards of human metabolites for other important alternative plasticizers apart from DINCH (e.g. DEHTP, di(2-propylheptyl) phthalate (DPHP), di(2-ethylhexyl) adipate (DEHA) and acetyl tributyl citrate (ATBC)) are not commercially available, we further investigated the urine and finger nail samples by Q Exactive Orbitrap LC-MS to identify specific metabolites, which can be used as appropriate biomarkers of human exposure. Many metabolites of alternative plasticizers that were present in in vitro extracts were further identified in vivo in urine and finger nail samples. Hence, we concluded that in vitro assays can reliably mimic the in vivo processes. Also, finger nails may be a useful non-invasive matrix for human biomonitoring of specific organic contaminants, but further validation is needed. Concentrations of PEs and DINCH were also measured in duplicate diet, air, dust and hand wipes. External exposure, estimated based on dietary intake, air inhalation, dust ingestion and dermal uptake, was higher or equal to the back-calculated internal intake. By comparing these, we were able to explain the relative importance of different exposure pathways for the Norwegian study population. Dietary intake was the predominant exposure route for all analyzed substances. Inhalation was important only for lower molecular weight PEs, while dust ingestion was important for higher molecular weight PEs and DINCH. Dermal uptake based on hand wipes was much lower than the total dermal uptake calculated via air, dust and personal care products, but still several research gaps remain for this exposure pathway. Based on calculated intakes, the exposure risk for the Norwegian participants to the PEs and DINCH did not exceed the established tolerable daily intake and reference doses, and the cumulative risk assessment for combined exposure to plasticizers with similar toxic endpoints indicated no health concerns for the selected population. Nevertheless, exposure to alternative plasticizers, such as DPHP and DINCH, is expected to increase in the future and continuous monitoring is required. Findings through uni- and multivariate analysis suggested that age, smoking, use of personal care products and many other everyday habits, such as washing hands or eating food from plastic packages are possible contributors to plasticizer exposure.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.
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Olujimi, Olanrewaju Olusoji. "The concentrations, distribution and health risk assessment of suspected endocrine disrupting chemicals (phenols, phthalates and heavy metals) in freshwater systems of Cape Town, South Africa." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/2009.
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Thesis (DTech (Environmental Health))--Cape Peninsula University of Technology, 2012.Environmental pollution with persistent organic chemicals and inorganic trace metals is an increasingly important issue. Recently, a variety of chemicals are introduced in a very large scale on the surface water network. The main pathway of these pollutants into the environment was identified as wastewater treatment plants (WWTPs). The extended use of chemicals in many product formulations and insufficient WWTPs has lead to an increase in the levels of the detected micro-pollutants wastewater effluents. The majority of these compounds are characterized by a rather poor biodegradability. A large spectrum of pollutants present in waste as traces has been reported to exert adverse effects on human and wildlife. Even though compounds are found in wastewater in a very small amount, they may have the undesirable capability of initiating health effect on various high forms of life. This survey constitutes the first study in the City of Cape Town to report data for a variety of priority substances (phenols and phthalate esters) in WWTP effluents and receiving rivers. These results are of critical importance since the data generated are used to generate potential health risk associated with both the organic and inorganic compounds analyzed.
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Bergé, Alexandre. "Identification des sources d’alkylphénols et de phtalates en milieu urbain : comparaison des rejets à dominante urbaine (domestique) par rapport à des rejets purement industriels." Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1113/document.
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Les phtalates et les alkylphénols sont des composés organiques générés par l'industrie chimique, qui entrent dans la composition des matières plastiques, pour les phtalates, et des détergents, pour les alkylphénols. Leurs productions mondiales avoisinent les 6 millions de tonnes pour les phtalates et 500 000 tonnes pour les alkylphénols. Ces composés sont considérés comme ubiquitaires dans l'environnement, c'est-à-dire qu'ils sont retrouvés dans tous les compartiments environnementaux (de l'atmosphère au milieu naturel). Par ailleurs, ils sont considérés comme des perturbateurs endocriniens et peuvent donc causer des dommages aux faunes et flores présentes dans le milieu naturel. Ce travail de thèse a permis de déterminer les niveaux de contamination des eaux usées en phtalates et alkylphénols dans plusieurs compartiments environnementaux situés en zone urbaine. Ainsi, des prélèvements effectués, par temps sec, ont permis de déterminer la qualité des eaux brutes vis-à-vis des paramètres globaux, des phtalates et des alkylphénols dans les rejets industriels, domestiques, les émissaires parisiens ainsi que dans les eaux usées transitant au sein d'une station d'épuration majeure d'Ile-de-France (Seine Centre, Colombes, 92). Ces résultats reflètent certaines spécificités et disparités du réseau d'assainissement, notamment marqués par la forte variabilité qui entoure, à la fois, le prélèvement et les niveaux de contamination par ces micropolluants. Au niveau des rejets industriels, de forts contrastes ont été observés entre les différents secteurs répertoriés (traitement des textiles, traitement de surface, métallurgie, industries pharmaceutiques, etc.). Globalement, les résultats des flux par équivalent-habitant soulignent que les apports domestiques sont la première source de contamination pour ces polluants en région parisienne. En effet, la contribution des apports industriels est inférieure à 5 %, pour tous les composés, quelque soit le secteur industriel considéré. L'étude des émissaires parisiens a permis de montrer une certaine stabilité temporelle de la qualité des effluents dans la partie avale du réseau d'assainissement. En revanche, cette étude a également mis en exergue des divergences et des similitudes entre les sous-bassins versants drainés par les différents émissaires. Ainsi, une étude statistique a montré que les émissaires Saint Denis Achères et Clichy Achères Argenteuil apparaissent significativement plus contaminés que les émissaires Sèvres Achères Reuil et Clichy Achères Bezons. Au niveau de l'efficacité des ouvrages de traitement, les résultats obtenus pour la station d'épuration de Seine Centre ont confirmé son efficacité pour les paramètres globaux communément utilisés pour déterminer la qualité des eaux usées. D'autre part, les résultats obtenus sur l'abattement des phtalates et des alkylphénols (rendements supérieurs à 83 % pour tous les composés) soulignent que même si les stations d'épuration ne sont, initialement, pas construites pour réduire et/ou éliminer les micropolluants, elles y parviennent de façon significative. A l'échelle des ouvrages, le traitement primaire par décantation physico-chimique lamellaire a permis de mettre en évidence l'élimination des polluants hydrophobes tels que le DEHP, le NP, le DnBP et le BBP. Le traitement secondaire par biofiltration a mis en exergue son efficacité à abattre significativement tous les polluants, aussi bien les composés légers (DEP) que les autres composésPhthalates and alkylphenols are organic molecules generated by the chemical industry, entering the composition of plastics, for phthalates, and detergents for alkylphenols. Their worldwide productions are around 6 million tons and 500,000 tons, respectively. It is now obvious from the concentrations and contents measured in the various environmental compartments that phthalates and alkylphenols are ubiquitous environmental contaminants. Indeed, they are found in all environmental compartments (from the atmosphere to the natural environment) at significant levels. These contaminants are also recognized as endocrine disrupting compounds and can cause damages to fauna and flora present in the natural environment. This work has identified levels of wastewater contamination of phthalates and alkylphenols in various environmental compartments in urban areas. Thus, samples taken, during dry weather periods, were used to determine the quality of raw water for global parameters, phthalates and alkylphenols within industrial and domestical discharges as well as the sewer network and a major Parisian sewage treatment plant (Seine Centre, Colombes, 92). These results reflect certain characteristics and disparities of the sewer network, including both high variability of the sampling and the contamination levels by these micropollutants. For industrial discharges, significant disparities have been observed between the different sectors listed (textile manufacturing, surface treatment, metallurgy, pharmaceutical industries, etc.). Overall, the results confirm that household inputs correspond to the first source of contamination in Parisian conurbation. Indeed, the contribution of industrial inputs is less than 5%, for all compounds, whatever the industrial sector. The study of the Parisian sewer network showed some temporal stability of wastewaters in the downstream part. This work however also highlighted disparities and similarities between the sub-watersheds drained by the sewer network. Thus, the northern part of the Parisian network (SDA and CAA) appears to be more contaminated than the Southern part (CAB and SAR).The results obtained for Seine Centre wastewater treatment plant (WWTP) confirms the effectiveness of the treatment processes on the removal on the routine water quality parameters. Additionally, the results on the elimination of phthalates and alkylphenols in sewage treatment plant (yields above 83% for all compounds) confirm that even if WWTP are initially not designed for reducing and/or eliminating micropollutants, they proceed significantly. During primary treatment, physicochemical lamellar clarification underlined the removal of hydrophobic pollutants such as DEHP, NP, DnBP and BBP. During the secondary treatment, biofiltration highlighted its effectiveness in eliminating all pollutants, as well as volatile compounds (DEP) and other contaminants
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Clarke, Bradley, and Bradley clarke@student rmit edu au. "Persistent Organic Pollutants in Australian Sewage Sludge: Environmental Monitoring and Land Application Risk Assessment." RMIT University. Applied Sciences, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20081202.113842.
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Presented is a study of persistent organic pollutants in Australian sewage sludge, focusing on environmental monitoring and a sewage sludge land application human health risk contaminated with these compounds. The chemicals of concern were: Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and
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Lovett, Brendon. "Three molecular materials studied by positive muons and magnetometry." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365360.
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Sandreth, Sherry. "Drinking Water and Autism: Using Spatial Cluster Detection to Explore Patterns of Autism Cases in Lane County, Oregon." ScholarWorks, 2016. https://scholarworks.waldenu.edu/dissertations/2335.
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Autism Spectrum Disorders (ASD) are a complex array of neurological disorders with a diverse presentation, multiple etiologies, and long-term ramifications. Prevalence of ASD in the United States is about 1 in 50 children as of 2013, making it a significant public health problem. The etiology is not understood, and it is widely accepted that it is multicausal, with genetic and environmental influences. Prior research suggests an association between water source and ASD. Contaminants such as lead, arsenic, mercury, pharmaceuticals and pesticides found in water are associated with developmental disorders suggesting that a systematic review focused on water source was warranted. Following the integrative model of environmental health (IMEH), this study explored the relationship of water source and ASD prevalence among children in Lane County, Oregon. This cross-sectional study utilized retrospective data of 91 open cases in April 2014. The study used chi square and geographical information systems (GIS) aided by cluster analysis to generate risk maps. Investigation of sociodemographic variables allowed comparisons to national data by zip code. Findings indicated no significant relationships or clusters of ASD populations by zip code, and no significant relationships to comorbidities between private or municipal water supplies. The IMEH framework enabled an in-depth data characterization of ASD and underscored the need for additional environmental data and universally standardized comorbidity definitions. Implication for positive social change include recognizing the importance of using social services data in the search for ASD risk factors.
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Ishak, Hanane. "Solubilité aqueuse, coefficient de partage octanol-eau et pression de vapeur de contaminants alimentaires organiques de la famille des phthalates et alkylphénols : détermination expérimentale et modélisation." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1172.
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Cette étude s’attache à la caractérisation physico-chimique des contaminants des emballages alimentaires organiques, précisément les phtalates et les alkylphénols, en terme de solubilité aqueuse, coefficient de partage octanol-eau et pression de vapeur. Cette caractérisation se situe dans le cadre des règlementations REACH concernant l’identification des substances chimiques toxiques. Les mesures expérimentales de solubilité aqueuse sont effectuées par la méthode dynamique de saturation dans un intervalle de température [298.15-328.15K], celles du coefficient de partage octanol-eau avec la méthode « shake-flask » à 298.15. Les mesures de pression de vapeur sont réalisées avec la méthode dynamique de saturation dans un intervalle de température [313.15-423.15K] et validées avec la méthode statique. A partir de ces mesures, les coefficients de partage air-eau et octanol-air sont déterminés. En addition des mesures expérimentales, une prédiction de ces propriétés est effectuée avec les modèles thermodynamiques : UNIFAC originale, UNIQUAC, NRTL et COSMO-sac-dsp. A l’issue de ces résultats, une évaluation quantitative et qualitative de chacun des modèles est effectuée. Cette évaluation facilitera l’optimisation des paramètres de chacun des modèles des deux familles dans le but de créer un modèle de prédiction du phénomène de migration de l’emballage vers l’alimentThe aim of this study is the physical-chemical characterization of the organic food packaging contaminants, particularly phthalates and alkyl phenols, in terms of aqueous solubility, octanol-water partition coefficient and vapor pressure. This characterization falls within the scope of REACH regulations for the identification of chemical substances. The aqueous solubility measurements are performed using the dynamic saturation method in a temperature range of [298.15 – 328.15K], those of octanol-water partition coefficient with the “shake-flask” method at 298.15K. The vapor pressure measurements are carried out with the “dynamic saturation method” in a temperature range between 313.15 and 423.15K, and validated with the static method. These measurements are used in the determination of air-water and octnol-air partition coefficients. Beside experimental measurements, these poperties are predicted using thermodynamic models: UNIFAC originale, UNIQUAC, NRTL and COSMO-sac-dsp. A qualitative and quantitative evaluation is performed for each model. This evaluation will facilitate the optimization of the models’ parameters concerning phthalates and alkyl phenols in order to generate a model for the contaminants migration process
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Nakiwala, Dorothy. "Exposition prénatale aux phénols et aux phtalates, développement neurologique de l'enfant et rôle des hormones thyroïdiennes." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALS003.
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Contexte: L'augmentation rapide de la prévalence de certains troubles du neurodéveloppement nécessite une meilleure compréhension des facteurs de risque modifiables de ces troubles. Les femmes enceinte sont constamment exposés à plusieurs des phénols et les phtalates qui sont des perturbateurs endocriniens liés à divers effets neurotoxiques dans les études toxicologiques. L'un des mécanismes sous-jacents à ces effets pourrait être une action de ces composés sur l’axe thyroïdien.Objectifs: 1) De documenter si l'utilisation de produits de soin personnel pourrait influencer les concentrations urinaires de biomarqueurs d’exposition aux phénols chez les femmes enceintes; 2) d’évaluer les associations entre l'exposition prénatale aux phénols et aux phtalates et le neurodéveloppement des enfants; et 3) d’évaluer les associations entre l'exposition prénatale aux phénols et aux phtalates et les concentrations d'hormones thyroïdiennes chez la femme enceinte et le nouveau-né.Méthodes: Ce travail s’appuie sur trois cohortes françaises complémentaires; l’étude SEPAGES-faisabilité pour lesquelles nous disposions de multiples échantillons d'urine et d'informations détaillées sur leurs utilisations de produits de soin, la cohorte EDEN avec les concentrations urinaires maternelles de phénols et phtalates et, l’information sur la neurodéveloppement des enfants et la cohorte SEPAGES avec les concentrations urinaires maternelles de phénols et phtalates et le taux d'hormones thyroïdiennes pendant la grossesse et à la naissance.Résultats: Le nombre total d'utilisation de produits de soin était associé à une augmentation des concentrations urinaires de bisphénol S et des parabènes mais pas des autres phénols.Aucun des composés étudiés n’était associé négativement aux scores de quotient intellectuel. Les concentrations urinaires maternelles de bisphénol A étaient associées à plus de symptômes de type troubles relationnels à 3 ans et de comportements de type hyperactif à 5 ans. Le MnBP était associé à une augmentation des scores liés aux troubles émotionnels et relationnels à 3 ans, tandis que le MBzP était lui associé à une augmentation des scores liés aux troubles internalisés et les troubles relationnels. Enfin lorsque les scores de comportement étaient étudiés en tant que variables binaires, une association entre le triclosan et les scores liés aux troubles émotionnels était observée à 3 et 5 ans.Les concentrations urinaires de bisphénol A étaient négativement associées aux concentrations de thyréostimuline (TSH) maternelles tandis que le MBzP, était lui positivement associé aux Z-scores de thyroxine totale et le triclosan négativement associé au ratio TT3/TT4. Lorsque les expositions étaient étudiées en terciles, des relations non linéaires ont aussi été observées entre le triclosan et la TSH (relation en U) et le MnBP et la TSH (U inversé). Pour les nouveau-nés, après stratification sur le sexe, les concentrations urinaires maternelles de bisphénol A étaient positivement associées au niveau de TT4 chez les garçons tandis que le triclosan était négativement associé à cette hormone chez les filles.Conclusion: Les associations positives entre l’utilisation de produits de soin et les concentrations urinaires de parabènes étaient en accord avec les études précédentes sur le sujet. Notre étude était la première à mettre en évidence de telles associations avec le bisphénol S. Les associations observées entre les expositions prénatales au bisphénol A et au DBP et le comportement avaient déjà été mis en évidence dans des études précédentes chez de jeunes garçons. Pour ce qui est du triclosan notre étude était la première à s’intéresser aux associations avec le comportement. Les composés associés au comportement dans la cohorte EDEN ont tous été associés à au moins une hormone thyroidienne dans la cohorte SEPAGES, suggérant une possible perturbation de l'homéostasie des hormones thyroïdiennesContext: The increase in the prevalence of neurodevelopmental disorders warrants identification of the possible underlying modifiable risk factors. Pregnant women are constantly exposed to several phenols and phthalates that are endocrine disrupting chemicals and have been linked to various adverse neurodevelopmental outcomes in toxicological studies. One of the suggested mechanisms of neurotoxicity of these compounds is by disruption of the thyroid hormone pathway.Aims: 1) To document if the use of personal care products (PCP) could influence phenols biomarkers concentrations during pregnancy; 2) to assess associations between prenatal exposure to phenols and phthalates and child neurodevelopment; and 3) to assess associations between prenatal exposure to phenols and phthalates on the thyroid hormone levels of pregnant women and their newborns.Methods: We relied on three complementary cohorts; the SEPAGES-feasibility study with multiple urine samples and detailed, time-resolved information on PCP use, the EDEN cohort with maternal urinary concentrations of phenols, phthalates and information on child neurodevelopment and the SEPAGES cohort with information on gestational exposure to phenols and phthalates (assessed in 2 pools of 21 urine sample per participant) and levels of thyroid hormones levels during pregnancy and at birth.Results: The total number of PCP applications (without distinction) was positively associated with the parabens’ and bisphenol S urinary concentrations during pregnancy but not with other phenols assessed (benzophenone-3, triclosan and bisphenol A).No phenol or phthalate metabolite pregnancy concentration was negatively associated with IQ of boys at 5 years. Some associations with child behavior were observed at 3 and 5 years: Bisphenol A was positively associated with the relationship problems subscale at 3 years and the hyperactivity–inattention subscale scores at 5 years. Mono-n-butyl phthalate (MnBP) was positively associated with internalizing behavior, relationship problems, and emotional symptom scores at 3 years. Monobenzyl phthalate (MBzP) was positively associated with internalizing behavior and relationship problems scores at 3 years. After dichotomizing behavioral scores, triclosan tended to be positively associated with emotional symptom subscales at both 3 and 5 years.Regarding the associations with maternal hormones, bisphenol A was negatively associated with the Ln (TSH) z-score; MBzP, a metabolite of benzylbutyl phthalate (BBP), was positively associated with the TT4 z-score and triclosan was negatively associated with the TT3/TT4 ratio z-score. When biomarker concentrations were categorized in tertiles, we observed non-monotonic associations between TSH and triclosan (U-shape) and MnBP, a metabolite of di-n-butyl phthalate (DBP) (inverse U-shape). In newborns, only sex-specific effects were observed: bisphenol A was positively associated with the TT4 z-score in male newborns while triclosan was negatively associated with the TT4 z-score in females.Conclusion: Findings in this study concur with previous literature that PCPs use may contribute to exposure to parabens. Our study was the first to report associations between PCP use and bisphenol S, a substitute of bisphenol A. In line with previous studies, bisphenol A and various phthalates, including DBP and BBP exposure during pregnancy, were associated adverse behavioral symptoms among boys. Our study was the first to report adverse neurobehavioral effects in relation to triclosan exposure. The four compounds associated with adverse behavioral effects in EDEN were also associated with one or more thyroid hormone levels of mothers or newborns in the SEPAGES cohort, suggesting possible disruption of thyroid hormones homeostasis
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Zurek, Martin [Verfasser]. "Wirkungen der Phthalate DEHP [Di-(2-ethylhexyl)-phthalat] und MEHP [Mono-(2-ethylhexyl)-phthalat] und des Schwermetalls Cadmium auf die Zellen der Sertoli-Zelllinie SerW3 / Martin Zurek." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2011. http://d-nb.info/1026264774/34.
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Morgan, Marisa L. "Exposure to Endocrine Disrupting Compounds and Reproductive Toxicity in Women." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1586.
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The overall objective of the research presented in this dissertation was to assess exposure to endocrine disrupting chemicals (EDCs), polychlorinated biphenyls (PCBs), phthalates, and bisphenol A (BPA) in the general population and evaluate their associations with adverse reproductive health effects, including cancers, in women. Given the proven contribution of unopposed estrogens to the risk for endometrial neoplasia or breast cancer, renewed health concerns have aroused about estrogen mimicking EDCs found in food, personal care products or as environmental contaminants. Our meta-analysis showed that exposure to estrogen mimicking PCBs increased summary risk of breast cancer and endometriosis. We further evaluated the relationship between endometriosis and breast cancer, and EDCs using a bioinformatics method. Our bioinformatics approach was able to identify genes with the potential to be involved in interaction with PCB, phthalates and BPA that may be important to the development of breast cancer and endometriosis. Therefore, we hypothesized that exposure to EDCs such as PCBs, phthalates, and BPA, results in adverse reproductive health effects in women. Using subject data and biomarkers available from the Center for Disease Controls National Health and Nutrition Examination Survey database we conducted a cross-sectional study of EDCs in relation to self-reported history of endometriosis, uterine leiomyomas, breast cancer, cervical cancer, ovarian cancer, and uterine cancer. Significantly higher body burdens of PCBs were found in women diagnosed with breast cancer, ovarian cancer, and uterine cancer compared to women without cancer. PCB 138 was significantly associated with breast cancer, cervical cancer, and uterine cancer, while PCBs 74 and 118 were significantly associated with ovarian cancer. The sum of dioxin-like PCBs were significantly associated with ovarian cancer (OR of 2.02, 95% CI: 1.06-3.85) and the sum of non-dioxin-like PCBs were significantly associated with uterine cancer (OR of 1.12, 95%CI: 1.03-1.23). Significantly higher body burdens of PCBs were also found in women diagnosed with endometriosis and uterine leiomyomas. Documenting the exposure to EDCs among the general U.S. population, and identifying agents associated with reproductive toxicity have the potential to fill research gaps and facilitate our understanding of the complex role environmental chemicals play in producing toxicity in reproductive organs.
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Cabana, Teri. "The Total Picture: Multiple Chemical Exposures to Pregnant Women in the US – An NHANES Study of Data from 2003 through 2010." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3504.
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INTRODUCTION: Chemical exposures to US pregnant women have been shown to have adverse health impacts on both mother and fetus. A prior paper revealed that US pregnant women in 2003-2004 had widespread exposure to multiple chemicals. The goal of this research is to examine how environmental chemical exposures to US pregnant women have changed from 2003 to 2010 and to look further at the extent of simultaneous exposure to multiple chemicals in US pregnant women using biomonitoring data available through NHANES (the National Health and Nutritional Examination Survey). METHODS: Using available NHANES data from the following cycles (2003-2004, 2005-2006, 2007-2008, 2009-2010), we analyzed how environmental chemical exposures changed over time. Covariates were used and data was weighted to reflect the population of pregnant US women. Each cycle was then compared to the 2003-2004 cycle in order to assess how exposures have changed over time. We then looked at the data in an entirely different fashion. We examined the total number of chemicals detected in a given pregnant woman by chemical group. Finally, we looked at the total number of detects across various chemical groups and used the Fisher Exact Test to study how the distribution of detections changed in 2009-2010 compared to 2003-2004. RESULTS: While at least one-third of the chemicals analyzed showed one cycle that differed, exposure rates of individual chemicals were generally not increasing from 2003-2010. Median number of detections over chemical groups also did not show much difference over time. However, analysis of the change in frequency distributions revealed that, for some chemical groups, the frequency of detects in US pregnant woman significantly increased in 2010 compared to 2003. CONCLUSIONS: Widespread chemical exposures were seen in US pregnant women from 2003 through 2010. The number of chemical analytes detected in US pregnant women’s bodies is rising. Many chemicals studied had similar mechanisms of action and/or similar adverse health outcomes upon exposure which is known to result in a cumulative health effect. This research suggests that we need to focus not only on exposure rates of individual chemicals but also on the overall number of chemicals detected when assessing the overall picture of environmental chemical exposures to pregnant women in the US.
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Marie, Cécile. "Evaluation, prévention et perception des risques en santé environnementale - Réflexions à propos de l'exposition des femmes enceintes aux phtalates et substituts." Thesis, Université Clermont Auvergne (2017-2020), 2017. http://www.theses.fr/2017CLFAS019.
Full textAbstract:
L'exposition in utero aux substances chimiques, et en particulier aux perturbateurs endocriniens, fait l'objet de publications croissantes dans la littérature scientifique. Cette thèse est illustrée à travers l'exemple des phtalates et substituts. Les phtalates, utilisés en tant que plastifiants, pour assouplir le polychlorure de vinyle (PVC), entrent dans la composition de nombreux produits de consommation (emballage alimentaire, jouet, revêtement de sol et mur, vêtement, etc.). Ils sont également utilisés dans les cosmétiques, les produits ménagers, de bricolage et de jardinage. L'exposition in utero à certains phtalates a été associée à certains effets (modifications hormonale foetale, malformations de l'appareil reproducteur masculin, prématurité) [Article 1]. La mise en évidence de cette toxicité a conduit les industriels à utiliser des plastifiants alternatifs. Cependant, il existe actuellement peu de données relatives à l'exposition et à la toxicité de ces plastifiants de substitution. Le volet 1 de ce travail de thèse rentre dans le cadre de la démarche d'évaluation du risque sanitaire. Il est ciblé sur l'utilisation des tubulures médicales en PVC, source d'exposition aux plastifiants encore peu étudiée pour les femmes enceintes. Les objectifs étaient d'identifier et quantifier les plastifiants (phtalates et substituts) présents dans les dispositifs médicaux utilisés pour les femmes enceintes hospitalisées et de décrire l'utilisation de ces dispositifs médicaux (nombre, durée d'utilisation et médicaments en contact) [Article 2]. A terme, ces données, couplées à des études de migration (pour quantifier les plastifiants migrant de la tubulure vers la solution médicamenteuse) doivent permettre d'estimer l'exposition théorique des femmes enceintes à partir de l'utilisation des tubulures médicales. Le volet 2 porte sur les mesures de prévention et de promotion en santé environnementale. Plusieurs organismes internationaux ont récemment émis des recommandations à destination des professionnels de santé et reconnaissent leur rôle essentiel en prévention auprès des femmes enceintes. Les objectifs étaient d'évaluer la perception des risques et les mesures de prévention en santé environnementale, dont l'exposition aux phtalates, conseillées par les professionnels de santé en périnatalité d'une part [Articles 3 et 4], et adoptées par les femmes enceintes d'autre part [Article 5]. Ce volet a permis d'identifier des leviers et des obstacles à la prévention de l'exposition aux substances chimiques en FranceIn utero exposure to chemicals, especially endocrine disruptors, is increasingly documented in the scientific literature. This thesis is illustrated through the example of phthalates and substitutes. Phthalates, commonly used as plasticizers to soften polyvinyl chloride (PVC), are present in many consumer products (food packaging, toys, floor and wall coverings, clothing, etc.). They are also used in cosmetics, household products, DIY and gardening. In utero exposure to certain phthalates has been associated with some effects (fetal hormonal alteration, malformations of the male reproductive system, prematurity) [Article 1]. This toxicity has led manufacturers to use alternative plasticizers. However, these substitutes are still little investigated in terms of exposure and toxicity. Part 1 of this thesis is part of the health risk assessment process. It concerned the use of PVC medical tubing, source of exposure to plasticizers little studied for pregnant women. The objectives were to identify and quantify the plasticizers (phthalates and substitutes) present in the medical devices used for hospitalized pregnant women and to describe the use of these medical devices (number, duration of use and medicines in contact) [Article 2]. These data combined with migration studies (to quantify plasticizers migrating from the tubing to the drug solution) can be used to estimate the theoretical exposure of pregnant women from the use of medical tubing. Part 2 focuses on environmental health prevention and promotion. Several international organizations have recently issued recommendations for health professionals and recognize their essential role in the prevention of pregnant women. The objectives were to assess the risk perception and preventive measures in environmental health, including exposure to phthalates, recommended by perinatal health professionals [Articles 3 and 4], and adopted by pregnant women [Article 5]. These data allowed to identify the levers and obstacles to the prevention of exposure to chemical substances in France. Keywords: , ,