Artículos de revistas: "DDT (Insecticide) Environmental aspects"

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Kampango, Ayubo, Emma F. Hocke, Helle Hansson, Peter Furu, Khamis A. Haji, Jean-Philippe David, Flemming Konradsen et al. "High DDT resistance without apparent association to kdr and Glutathione-S-transferase (GST) gene mutations in Aedes aegypti population at hotel compounds in Zanzibar". PLOS Neglected Tropical Diseases 16, n.º 5 (16 de mayo de 2022): e0010355. http://dx.doi.org/10.1371/journal.pntd.0010355.

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Global efforts to control Aedes mosquito-transmitted pathogens still rely heavily on insecticides. However, available information on vector resistance is mainly restricted to mosquito populations located in residential and public areas, whereas commercial settings, such as hotels are overlooked. This may obscure the real magnitude of the insecticide resistance problem and lead to ineffective vector control and resistance management. We investigated the profile of insecticide susceptibility of Aedes aegypti mosquitoes occurring at selected hotel compounds on Zanzibar Island. At least 100 adults Ae. aegypti females from larvae collected at four hotel compounds were exposed to papers impregnated with discriminant concentrations of DDT (4%), permethrin (0.75%), 0.05 deltamethrin (0.05%), propoxur (0.1%) and bendiocarb (0.1%) to determine their susceptibility profile. Allele-specific qPCR and sequencing analysis were applied to determine the possible association between observed resistance and presence of single nucleotide polymorphisms (SNPs) in the voltage-gated sodium channel gene (VGSC) linked to DDT/pyrethroid cross-resistance. Additionally, we explored the possible involvement of Glutathione-S-Transferase gene (GSTe2) mutations for the observed resistance profile. In vivo resistance bioassay indicated that Ae. aegypti at studied sites were highly resistant to DDT, mortality rate ranged from 26.3% to 55.3% and, moderately resistant to deltamethrin with a mortality rate between 79% to and 100%. However, genotyping of kdr mutations affecting the voltage-gated sodium channel only showed a low frequency of the V1016G mutation (n = 5; 0.97%). Moreover, for GSTe2, seven non-synonymous SNPs were detected (L111S, C115F, P117S, E132A, I150V, E178A and A198E) across two distinct haplotypes, but none of these were significantly associated with the observed resistance to DDT. Our findings suggest that cross-resistance to DDT/deltamethrin at hotel compounds in Zanzibar is not primarily mediated by mutations in VGSC. Moreover, the role of identified GSTe2 mutations in the resistance against DDT remains inconclusive. We encourage further studies to investigate the role of other potential insecticide resistance markers.

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Guimarães, Raphael Mendonça, Carmen Ildes Rodrigues Fróes Asmus y Armando Meyer. "DDT reintroduction for malaria control: the cost-benefit debate for public health". Cadernos de Saúde Pública 23, n.º 12 (diciembre de 2007): 2835–44. http://dx.doi.org/10.1590/s0102-311x2007001200004.

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DDT is a persistent insecticide that was widely used in the world from the 1940s until the 70s, when it was banned in the United States and other countries. Most of its toxic effects are not observed in the acute forms, but particularly after chronic exposure. These long-term issues include reproductive effects, varying according to the time of life in which the individuals were exposed. The aims of the current study were to review the principal toxicological effects of DDT on reproduction, stratifying by physiological periods of exposure, and based on the magnitude of these effects, to discuss the cost-benefit relationship of reintroducing DDT with the specifically defined vector control criteria.

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Dores, Eliana Freire Gaspar de Carvalho, Leandro Carbo y Adley Bergson Gonçalves de Abreu. "Serum DDT in malaria vector control sprayers in Mato Grosso State, Brazil". Cadernos de Saúde Pública 19, n.º 2 (abril de 2003): 429–37. http://dx.doi.org/10.1590/s0102-311x2003000200009.

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DDT was used intensively in vector control programs in Mato Grosso State until 1997. The present study aimed to determine DDT concentrations in blood samples from Brazilian National Health Foundation workers in Mato Grosso. Blood samples were analyzed from 41 sprayers, 20 drivers, and 14 unexposed workers, collected in June 1999 and October 2000 in two regions of the State (Sinop and Cáceres). Sprayers and drivers were occupationally exposed, and no significant differences were found in serum DDT levels between these two groups in either region. Likewise, no significant differences were found in p,p'DDE and total DDT levels between Cáceres and Sinop. However, p,p'DDT levels were higher in Sinop due to the intensive use of this insecticide in the region in recent years. The two regions together showed the following results: total DDT ranging from 7.50µg/L to 875.5µg/L (median = 135.5µg/L) for sprayers; from 34.5µg/L to 562.3µg/L (median = 147.7µg/L) for drivers; and from undetected to 94.8µg/L (median = 22.5µg/L) for unexposed workers.

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Poniman, Tri Retnaningsih Soeprobowowati y Muhammad Helmi. "Geospatial distributions of organochlorine insecticide in shallot agriculture land at Wanasari sub-district, Brebes regency, Central Java, Indonesia". E3S Web of Conferences 202 (2020): 06009. http://dx.doi.org/10.1051/e3sconf/202020206009.

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The organochlorine insecticide is a POPs compound that was monitored according to the Stockholm convention in 2003 because it can cause environmental damage and threaten human health. The study of the distribution of organochlorine insecticides on onion farms has been carried out in the village area in Wanasari sub-District and Brebes Regency. This study was conducted in March-June 2019, with the scope of soil sampling, organochlorine insecticide residue analysis, and spline interpolation. To determine the number of organochlorine insecticide residues using the SNI 06-6991.1-2004 method, while to determine the distribution pattern using the Spline interpolation method with the ArcGIS 10.4. In preparing geospatial residues, we use the ratio of the maximum residual limit (MRLs) of each organochlorine active ingredient. These research sites can be categorized as severe pollution of OCPs insecticides. In this study OCPs residues (Aldrin, Lindane, and Heptachlor, DDT, Endrin, and Dieldrin) can be found with concentrations above the MRLs requirements. OCPs residues with very high range characteristics are shown by Aldrin, DDT, Endrin, and Dieldrin each of more than 50% of the total observed land area. Point numbers six detected all OCPs residues were observed with concentrations exceeding MRLs.

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Deb, Rinki, Rudra Pratap Singh, Prabhas Kumar Mishra, Lisa Hitchins, Emma Reid, Arti Manorama Barwa, Debanjan Patra et al. "Impact of IRS: Four-years of entomological surveillance of the Indian Visceral Leishmaniases elimination programme". PLOS Neglected Tropical Diseases 15, n.º 8 (9 de agosto de 2021): e0009101. http://dx.doi.org/10.1371/journal.pntd.0009101.

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Background In 2005, Bangladesh, India and Nepal agreed to eliminate visceral leishmaniasis (VL) as a public health problem. The approach to this was through improved case detection and treatment, and controlling transmission by the sand fly vector Phlebotomus argentipes, with indoor residual spraying (IRS) of insecticide. Initially, India applied DDT with stirrup pumps for IRS, however, this did not reduce transmission. After 2015 onwards, the pyrethroid alpha-cypermethrin was applied with compression pumps, and entomological surveillance was initiated in 2016. Methods Eight sentinel sites were established in the Indian states of Bihar, Jharkhand and West Bengal. IRS coverage was monitored by household survey, quality of insecticide application was measured by HPLC, presence and abundance of the VL vector was monitored by CDC light traps, insecticide resistance was measured with WHO diagnostic assays and case incidence was determined from the VL case register KAMIS. Results Complete treatment of houses with IRS increased across all sites from 57% in 2016 to 70% of houses in 2019, rising to >80% if partial house IRS coverage is included (except West Bengal). The quality of insecticide application has improved compared to previous studies, average doses of insecticide on filters papers ranged from 1.52 times the target dose of 25mg/m2 alpha-cypermethrin in 2019 to 1.67 times in 2018. Resistance to DDT has continued to increase, but the vector was not resistant to carbamates, organophosphates or pyrethroids. The annual and seasonal abundance of P. argentipes declined between 2016 to 2019 with an overall infection rate of 0.03%. This was associated with a decline in VL incidence for the blocks represented by the sentinel sites from 1.16 per 10,000 population in 2016 to 0.51 per 10,000 in 2019. Conclusion Through effective case detection and management reducing the infection reservoirs for P. argentipes in the human population combined with IRS keeping P. argentipes abundance and infectivity low has reduced VL transmission. This combination of effective case management and vector control has now brought India within reach of the VL elimination targets.

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Mbabazi, Jolocam. "DDT in indoor residual spraying: human health aspects". International Journal of Environmental Studies 70, n.º 4 (agosto de 2013): 663–64. http://dx.doi.org/10.1080/00207233.2013.813714.

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Tkachenko, I. V. "Hygienic assessment of potential ecotoxicological risk of the use of new insecticide spiromesifen in agriculture of Ukraine". Environment & Health, n.º 4 (101) (noviembre de 2021): 62–67. http://dx.doi.org/10.32402/dovkil2021.04.062.

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Objective: The aim of our work was to study the potential ecotoxicological hazard of a new chemical from the class of tetramic and tetronic acid derivatives - the insecticide spiromesifen, taking into account its physico-chemical properties and impact on the environmental objects. Materials and methods: An assessment of the potential danger of spiromesifen use for ecosystems was carried out on the basis of the calculation of the ecotoxicological hazard (ecotox) by N.N. Melnikov’s method. The field studies were carried out in different agro-climatic zones of Ukraine. The treatment of vineyards and apple trees was carried out at the maximum consumption rates of spiromesifen. Results: According to the literary data and our research, it was found that in the soil-and-climatic conditions of Ukraine, the ecotoxicological risk, when using the new insecticide spiromesifen, is 10,000 times and 7,000 times low than the analogous characteristics of DDT. Ecotox abamectin is 154 times low than ecotox DDT. This makes preparations, based on these substances, more promising and competitive among other pesticides in agricultural use. We can conclude that spiromesifen does not pose a threat to terrestrial ecosystems and health of the population.

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Collins, Emma L., Jody E. Phelan, Magdalena Hubner, Anton Spadar, Monica Campos, Daniel Ward, Holly Acford-Palmer et al. "A next generation targeted amplicon sequencing method to screen for insecticide resistance mutations in Aedes aegypti populations reveals a rdl mutation in mosquitoes from Cabo Verde". PLOS Neglected Tropical Diseases 16, n.º 12 (13 de diciembre de 2022): e0010935. http://dx.doi.org/10.1371/journal.pntd.0010935.

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Aedes mosquito vectors transmit many viruses of global health concern, including dengue, chikungunya and Zika. These vector-borne viral diseases have a limited number of treatment options, and vaccines vary in their effectiveness. Consequently, integrated vector management is a primary strategy for disease control. However, the increasing emergence and spread of insecticide resistance is threatening the efficacy of vector control methods. Identifying mutations associated with resistance in vector populations is important to monitor the occurrence and evolution of insecticide resistance and inform control strategies. Rapid and cost-effective genome sequencing approaches are urgently needed. Here we present an adaptable targeted amplicon approach for cost-effective implementation within next generation sequencing platforms. This approach can identify single nucleotide polymorphisms (SNPs) and small insertions and deletions (indels) in genes involved in insecticide resistance in Aedes aegypti mosquitoes. We designed and tested eleven amplicons, which included segments of the ace-1 (carbamate target), the Voltage-Gated Sodium Channel (vgsc; pyrethroids, DDT and organochlorines), and rdl (dieldrin) genes; thereby covering established knockdown resistance (kdr) mutations (e.g., S989P, I1011M/V, V1016G/I and F1534C), with the potential to identify novel ones. The amplicon assays were designed with internal barcodes, to facilitate multiplexing of large numbers of mosquitoes at low cost, and were sequenced using an Illumina platform. Our approach was evaluated on 152 Ae. aegypti mosquitoes collected in Cabo Verde, an archipelago with a history of arbovirus outbreaks. The amplicon sequence data revealed 146 SNPs, including four non-synonymous polymorphisms in the vgsc gene, one in ace-1 and the 296S rdl mutation previously associated with resistance to organochlorines. The 296S rdl mutation was identified in 98% of mosquitoes screened, consistent with the past use of an organochlorine compound (e.g., DDT). Overall, our work shows that targeted amplicon sequencing is a rapid, robust, and cost-effective tool that can be used to perform high throughput monitoring of insecticide resistance.

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Galván-Portillo, Marcia, Carlos Jiménez-Gutiérrez, Luisa Torres-Sánchez y Lizbeth López-Carrillo. "Food consumption and adipose tissue DDT levels in Mexican women". Cadernos de Saúde Pública 18, n.º 2 (abril de 2002): 447–52. http://dx.doi.org/10.1590/s0102-311x2002000200009.

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This article analyzes food consumption in relation to levels of DDE (the principal metabolite of DDT) in the adipose tissue of 207 Mexican women residing in States with high and low exposure to DDT. Data on the women's dietary habits and childbearing history were obtained from a personal interview. Adipose tissue DDE levels were measured by gas-liquid chromatography and compared by analysis of variance (ANOVA) and multiple linear regression. Adipose tissue DDE levels increased significantly with age (p = 0.005) and residence in coastal areas (p = 0.002) and non-significantly with the consumption of onion, cauliflower, prickly pear, squash blossoms, sweet corn, broad beans, chili pepper sauce, ham, and fish. Even so, during breastfeeding there was a non-significant reduction in these levels. The findings suggest that certain foods serve as vehicles for DDE residues and confirm that breastfeeding is a mechanism for the elimination of this insecticide, which accumulates over the years in the human body.

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Maunder, John W. "Strategic aspects of insecticide resistance in head lice". Journal of the Royal Society of Health 111, n.º 1 (febrero de 1991): 24–26. http://dx.doi.org/10.1177/146642409111100109.

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Eremina, Olga Yurevna y Veronika Valentinovna Olifer. "Blood-sucking mosquitoes: some aspects of insecticide resistance". Disinfection affairs, n.º 4 (30 de septiembre de 2022): 19–25. http://dx.doi.org/10.35411/2076-457x-2022-3-19-25.

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The modern data of the world scientific literature on resistance to a wide range of insecticides from different chemical groups, concerning natural populations of the most epidemiologically significant species of blood-sucking mosquitoes belonging to the three genera Aedes, Culex, Anopheles, are presented. Most studies are carried out according to the recommendations of the World Health Organization method ("bottle test"). The distribution of resistance is patchy across regions and may vary within a country. A number of genetic mutations responsible for the development of resistance have been described. Keywords: blood-sucking mosquitoes, resistance, insecticides, mosquito Vectors,

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Matthiessen, Peter. "Contamination of wildlife with DDT insecticide residues in relation to tsetse fly control operations in Zimbabwe". Environmental Pollution Series B, Chemical and Physical 10, n.º 3 (1985): 189–211. http://dx.doi.org/10.1016/0143-148x(85)90043-6.

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Yáñez, Leticia, Vı́ctor H. Borja-Aburto, Emilio Rojas, Hortensia de la Fuente, Roberto González-Amaro, Humberto Gómez, Alejandro A. Jongitud y Fernando Dı́az-Barriga. "DDT induces DNA damage in blood cells. Studies in vitro and in women chronically exposed to this insecticide". Environmental Research 94, n.º 1 (enero de 2004): 18–24. http://dx.doi.org/10.1016/s0013-9351(03)00047-1.

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Moreno, M., J. L. Vicente, J. Cano, P. J. Berzosa, A. De Lucio, S. Nzambo, L. Bobuakasi et al. "Knockdown resistance mutations (kdr) and insecticide susceptibility to DDT and pyrethroids in Anopheles gambiae from Equatorial Guinea". Tropical Medicine & International Health 13, n.º 3 (6 de abril de 2008): 430–33. http://dx.doi.org/10.1111/j.1365-3156.2008.02010.x.

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Knight, Scott S. y Charles M. Cooper. "Insecticide and metal contamination of a mixed cover agricultural watershed". Water Science and Technology 33, n.º 2 (1 de enero de 1996): 227–34. http://dx.doi.org/10.2166/wst.1996.0052.

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Although pesticides used to control detrimental insects have changed since the wide spread use of highly persistent organochlorine insecticides in the 1940s through the 1970s, pesticides still present environmental problems. Random sampling of major watershed features of Otoucalofa Creek was conducted to study the distribution and concentration of residual and current use insecticides and metals in a mixed cover agricultural watershed. Samples of water, soil, sediment and fishes were taken from Otoucalofa Creek watershed and tested for 23 contaminants, including persistent organochlorine and current-use insecticides, PCBs and metals. Otoucalofa Creek watershed was chosen because of its location in the loess hills of northern Mississippi, USA, and the fact that its drainage includes 10,100 hectares of forest, 6,100 hectares of rowcrops, 4,900 hectares of pasture, and the small town of Water Valley (pop. 4,147). The greatest concentrations of insecticides were found in fish, but the highest concentrations of metals were found in soil and sediments. Six of 7 metals and 11 of 15 insecticides tested were present in fish samples. Arsenic and mercury averaged 0.67 μg/g and 0.31 μg/g, respectively, in soil samples and 0.25 μg/g and 0.03 μg/g in sediment samples, but were in lower concentrations in fish tissue. Relatively high concentrations of zinc were found in soil and sediment. DDT and its metabolites averaged 118 ng/g in fish, averaged only 1.90 ng/g in sediments and were undetectable in soil. Contamination of water was dependent upon storm related discharge and is therefore a transient phenomenon. Water samples taken during normal flow had the lowest concentrations of both metals and insecticides. Storm flow (High Stage) samples had significantly higher concentrations of insecticides and metals than did normal flow. Since arsenic is the only persistent contaminant still being applied to agricultural land, concentrations of residual insecticides should steadily decline. Current use insecticides were only detected seasonally and in extremely low concentrations, however, this transient, short term exposure, which may not have been as detrimental with less toxic organochlorine pesticides, is more significant with acutely toxic current use compounds.

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Sene, Ndeye Marie, Konstantinos Mavridis, El Hadji Ndiaye, Cheikh Tidiane Diagne, Alioune Gaye, El Hadji Malick Ngom, Yamar Ba et al. "Insecticide resistance status and mechanisms in Aedes aegypti populations from Senegal". PLOS Neglected Tropical Diseases 15, n.º 5 (10 de mayo de 2021): e0009393. http://dx.doi.org/10.1371/journal.pntd.0009393.

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Aedes aegypti is the main epidemic vector of arboviruses in Africa. In Senegal, control activities are mainly limited to mitigation of epidemics, with limited information available for Ae. aegypti populations. A better understanding of the current Ae. aegypti susceptibility status to various insecticides and relevant resistance mechanisms involved is needed for the implementation of effective vector control strategies. The present study focuses on the detection of insecticide resistance and reveals the related mechanisms in Ae. aegypti populations from Senegal. Bioassays were performed on Ae. aegypti adults from nine Senegalese localities (Matam, Louga, Barkedji, Ziguinchor, Mbour, Fatick, Dakar, Kédougou and Touba). Mosquitoes were exposed to four classes of insecticides using the standard WHO protocols. Resistance mechanisms were investigated by genotyping for pyrethroid target site resistance mutations (V1016G, V1016I, F1534C and S989P) and measuring gene expression levels of key detoxification genes (CYP6BB2, CYP9J26, CYP9J28, CYP9J32, CYP9M6, CCEae3a and GSTD4). All collected populations were resistant to DDT and carbamates except for the ones in Matam (Northern region). Resistance to permethrin was uniformly detected in mosquitoes from all areas. Except for Barkédji and Touba, all populations were characterized by a susceptibility to 0.75% Permethrin. Susceptibility to type II pyrethroids was detected only in the Southern regions (Kédougou and Ziguinchor). All mosquito populations were susceptible to 5% Malathion, but only Kédougou and Matam mosquitoes were susceptible to 0.8% Malathion. All populations were resistant to 0.05% Pirimiphos-methyl, whereas those from Louga, Mbour and Barkédji, also exhibited resistance to 1% Fenitrothion. None of the known target site pyrethroid resistance mutations was present in the mosquito samples included in the genotyping analysis (performed in > 1500 samples). In contrast, a remarkably high (20-70-fold) overexpression of major detoxification genes wasobserved, suggesting that insecticide resistance is mostly mediated through metabolic mechanisms. These data provide important evidence to support dengue vector control in Senegal.

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Catalá, SS, LB Crocco, A. Muñoz, G. Morales, I. Paulone, E. Giraldez, C. Candioti y C. Ripol. "Entomological aspects of Chagas' disease transmission in the domestic habitat, Argentina". Revista de Saúde Pública 38, n.º 2 (abril de 2004): 216–22. http://dx.doi.org/10.1590/s0034-89102004000200010.

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OBJECTIVE: To study the risk of Trypanosoma cruzi domestic transmission using an entomological index and to explore its relationship with household's characteristics and cultural aspects. METHODS: There were studied 158 households in an endemic area in Argentina. Each household was classified according to an entomological risk indicator (number of risky bites/human). A questionnaire was administered to evaluate risk factors among householders. RESULTS: Infested households showed a wide range of risk values (0 to 5 risky bites/human) with skewed distribution, a high frequency of lower values and few very high risk households. Of all collected Triatoma infestans, 44% had had human blood meals whereas 27% had had dogs or chickens blood meals. Having dogs and birds sharing room with humans increased the risk values. Tidy clean households had contributed significantly to lower risk values as a result of low vector density. The infested households showed a 24.3% correlation between time after insecticide application and the number of vectors. But there was no correlation between the time after insecticide application and T. infestans' infectivity. The statistical analysis showed a high correlation between current values of the entomological risk indicator and Trypanosoma cruzi seroprevalence in children. CONCLUSIONS: The risk of T. cruzi domestic transmission assessed using an entomological index show a correlation with children seroprevalence for Chagas' disease and householders' habits.

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Dapeng, Luo, Yao Renguo, Song Jinduo, Huo Hongru y Wang Ze. "The effect of DDT spraying and bed nets impregnated with pyrethroid insecticide on the incidence of Japanese encephalitis virus infection". Transactions of the Royal Society of Tropical Medicine and Hygiene 88, n.º 6 (noviembre de 1994): 629–31. http://dx.doi.org/10.1016/0035-9203(94)90200-3.

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Spickett, JT, PJ Dolin, MR Phillips y CJM Priestley. "Patterns of Pesticide Usage by Cereal Crop Farmers in Western Australia". Asia Pacific Journal of Public Health 3, n.º 3 (julio de 1989): 242–48. http://dx.doi.org/10.1177/101053958900300312.

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In Western Australia there has been an increase in the use of herbicides in recent years due to a change in farming practices. This change, together with more general public concern over exposure to chemicals, has resulted in farmers expressing concern over the possible long term health effects from exposure to herbicides. As part of a long term study of the possible health effects from such exposure, a survey was carried out to establish the extent of pesticide use within the cereal farming community of Western Australia. Of the 9, 408 properties surveyed, 2, 921 responses were received which represents a 32.2% response rate. The results indicate that a wide range of chemicals are used as insecticides, fumigants, seed dressings, seed pickles, herbicides, and rodent poisons. At the time of the survey in 1985, products containing prespruf and 1, 1, 1-trichloro-2, 2-bis (p-chlorophenyl)ethane (DDT) were the most popular insecticide, and products containing diquat, diclofop-methyl, chlorsulfuron and glyphosate as activeingredients represented the four most popular herbicides.

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Rai, Priyanka y Dhiraj Saha. "Occurrence of L1014F and L1014S mutations in insecticide resistant Culex quinquefasciatus from filariasis endemic districts of West Bengal, India". PLOS Neglected Tropical Diseases 16, n.º 1 (13 de enero de 2022): e0010000. http://dx.doi.org/10.1371/journal.pntd.0010000.

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Introduction Lymphatic filariasis causes long term morbidity and hampers the socio-economic status. Apart from the available treatments and medication, control of vector population Culex quinquefasciatus Say through the use of chemical insecticides is a widely applied strategy. However, the unrestrained application of these insecticides over many decades has led to resistance development in the vectors. Methods In order to determine the insecticide susceptibility/resistance status of Cx. quinquefasciatus from two filariasis endemic districts of West Bengal, India, wild mosquito populations were collected and assayed against six different insecticides and presence of L1014F; L1014S kdr mutations in the voltage-gated sodium channel gene was also screened along with the use of synergists to evaluate the role of major detoxifying enzymes in resistance development. Results The collected mosquito populations showed severe resistance to insecticides and the two synergists used–PBO (piperonyl butoxide) and TPP (triphenyl phosphate), were unable to restore the susceptibility status of the vector thereupon pointing towards a minor role of metabolic enzymes. kdr mutations were present in the studied populations in varying percent with higher L1014F frequency indicating its association with the observed resistance to pyrethroids and DDT. This study reports L1014S mutation in Cx. quinquefasciatus for the first time.

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Manaca, Maria N., Joan O. Grimalt, Jordi Sunyer, Inacio Mandomando, Raquel Gonzalez, Jahit Sacarlal, Carlota Dobaño, Pedro L. Alonso y Clara Menendez. "Concentration of DDT compounds in breast milk from African women (Manhiça, Mozambique) at the early stages of domestic indoor spraying with this insecticide". Chemosphere 85, n.º 3 (octubre de 2011): 307–14. http://dx.doi.org/10.1016/j.chemosphere.2011.06.015.

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Begum, Ghousia y Shantha Vijayaraghavan. "Effect of Acute Exposure of the Organophosphate Insecticide Rogor on Some Biochemical Aspects ofClarias batrachus(Linnaeus)". Environmental Research 80, n.º 1 (enero de 1999): 80–83. http://dx.doi.org/10.1006/enrs.1998.3871.

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Agyekum, Thomas P., Paul K. Botwe, John Arko-Mensah, Ibrahim Issah, Augustine A. Acquah, Jonathan N. Hogarh, Duah Dwomoh, Thomas G. Robins y Julius N. Fobil. "A Systematic Review of the Effects of Temperature on Anopheles Mosquito Development and Survival: Implications for Malaria Control in a Future Warmer Climate". International Journal of Environmental Research and Public Health 18, n.º 14 (7 de julio de 2021): 7255. http://dx.doi.org/10.3390/ijerph18147255.

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The rearing temperature of the immature stages can have a significant impact on the life-history traits and the ability of adult mosquitoes to transmit diseases. This review assessed published evidence of the effects of temperature on the immature stages, life-history traits, insecticide susceptibility, and expression of enzymes in the adult Anopheles mosquito. Original articles published through 31 March 2021 were systematically retrieved from Scopus, Google Scholar, Science Direct, PubMed, ProQuest, and Web of Science databases. After applying eligibility criteria, 29 studies were included. The review revealed that immature stages of An. arabiensis were more tolerant (in terms of survival) to a higher temperature than An. funestus and An. quadriannulatus. Higher temperatures resulted in smaller larval sizes and decreased hatching and pupation time. The development rate and survival of An. stephensi was significantly reduced at a higher temperature than a lower temperature. Increasing temperatures decreased the longevity, body size, length of the gonotrophic cycle, and fecundity of Anopheles mosquitoes. Higher rearing temperatures increased pyrethroid resistance in adults of the An. arabiensis SENN DDT strain, and increased pyrethroid tolerance in the An. arabiensis SENN strain. Increasing temperature also significantly increased Nitric Oxide Synthase (NOS) expression and decreased insecticide toxicity. Both extreme low and high temperatures affect Anopheles mosquito development and survival. Climate change could have diverse effects on Anopheles mosquitoes. The sensitivities of Anopeheles mosquitoes to temperature differ from species to species, even among the same complex. Notwithstanding, there seem to be limited studies on the effects of temperature on adult life-history traits of Anopheles mosquitoes, and more studies are needed to clarify this relationship.

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Ahadji-Dabla, Koffi Mensah, Daniel Romero-Alvarez, Innocent Djègbè, Adjovi Djifa Amoudji, Georges Yawo Apétogbo, Rousseau Djouaka, Komlanvi Oboussoumi et al. "Potential Roles of Environmental and Socio-Economic Factors in the Distribution of Insecticide Resistance in Anopheles gambiae sensu lato (Culicidae: Diptera) Across Togo, West Africa". Journal of Medical Entomology 57, n.º 4 (29 de febrero de 2020): 1168–75. http://dx.doi.org/10.1093/jme/tjaa023.

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Abstract Vector control strategies recommended by the World Health Organization are threatened by resistance of Anopheles mosquitoes to insecticides. Information on the distribution of resistant genotypes of malaria vectors is increasingly needed to address the problem. Ten years of published and unpublished data on malaria vector susceptibility/resistance and resistance genes have been collected across Togo. Relationships between the spatial distribution of resistance status and environmental, socio-economic, and landscape features were tested using randomization tests, and calculating Spearman rank and Pearson correlation coefficients between mosquito mortality and different gridded values. Anopheles gambiae sensu lato was resistant to DDT, pyrethroids, and the majority of carbamates and organophosphates. Three sibling species were found (i.e., An. gambiae, Anopheles coluzzii, and Anopheles arabiensis) with four resistance genes, including kdr (L1014F, L1014S, and N1575Y) and ace1 (G119S). The most frequent resistance gene was L1014F. Overall, no association was found between the susceptibility/resistance status and environmental features, suggesting that evolution of resistance may be most closely related to extreme selection from local insecticide use. Nevertheless, further research is necessary for firm conclusions about this lack of association, and the potential role of landscape characteristics such as presence of crops and percentage of tree cover.

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Roy, Lalita, Surendra Uranw, Kristien Cloots, Tom Smekens, Usha Kiran, Uttam Raj Pyakurel, Murari Lal Das, Rajpal S. Yadav y Wim Van Bortel. "Susceptibility status of the wild-caught Phlebotomus argentipes (Diptera: Psychodidae: Phlebotominae), the sand fly vector of visceral leishmaniasis, to different insecticides in Nepal". PLOS Neglected Tropical Diseases 16, n.º 7 (14 de julio de 2022): e0010304. http://dx.doi.org/10.1371/journal.pntd.0010304.

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Background Visceral leishmaniasis (VL) is targeted for elimination as a public health problem in Nepal by 2023. For nearly three decades, the core vector control intervention in Nepal has been indoor residual spraying (IRS) with pyrethroids. Considering the long-term use of pyrethroids and the possible development of resistance of the vector Phlebotomus argentipes sand flies, we monitored the susceptibility status of their field populations to the insecticides of different classes, in villages with and without IRS activities in recent years. Methodology/Principal findings Sand flies were collected from villages with and without IRS in five VL endemic districts from August 2019 to November 2020. The WHO susceptibility test procedure was adopted using filter papers impregnated at the discriminating concentrations of insecticides of the following classes: pyrethroids (alpha-cypermethrin 0.05%, deltamethrin 0.05%, and lambda-cyhalothrin 0.05%), carbamates (bendiocarb 0.1%) and organophosphates (malathion 5%). Pyrethroid resistance intensity bioassays with papers impregnated with 5× of the discriminating concentrations, piperonyl butoxide (PBO) synergist-pyrethroid bioassays, and DDT cross-resistance bioassays were also performed. In the IRS villages, the vector sand flies were resistant (mortality rate <90%) to alpha-cypermethrin and possibly resistant (mortality rate 90–97%) to deltamethrin and lambda-cyhalothrin, while susceptibility to these insecticides was variable in the non-IRS villages. The vector was fully susceptible to bendiocarb and malathion in all villages. A delayed knockdown time (KDT50) with pyrethroids was observed in all villages. The pyrethroid resistance intensity was low, and the susceptibility improved at 5× of the discriminating concentrations. Enhanced pyrethroid susceptibility after pre-exposure to PBO and the DDT-pyrethroid cross-resistance were evident. Conclusions/Significance Our investigation showed that P. argentipes sand flies have emerged with pyrethroid resistance, suggesting the need to switch to alternative classes of insecticides such as organophosphates for IRS. We strongly recommend the regular and systematic monitoring of insecticide resistance in sand flies to optimize the efficiency of vector control interventions to sustain VL elimination efforts in Nepal.

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Faber, Claudia, Carlos Montenegro Quiñonez, Olaf Horstick, Kazi Mizanur Rahman y Silvia Runge-Ranzinger. "Indoor residual spraying for the control of visceral leishmaniasis: A systematic review". PLOS Neglected Tropical Diseases 16, n.º 5 (19 de mayo de 2022): e0010391. http://dx.doi.org/10.1371/journal.pntd.0010391.

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Indoor Residual Spraying (IRS) is one of the interventions to control the vectors of Visceral Leishmaniasis (VL). Different insecticides are used in affected countries, also in the Regional Initiative for the Elimination of VL in South-East Asia. This systematic review assesses all available studies analysing the effectiveness of IRS on the key vectors of VL. The systematic review followed PRISMA guidelines, with a broad search strategy, applied to seven key databases. Inclusion criteria were studies focusing on 1) Visceral leishmaniasis 2) Indoor Residual Spraying (IRS) or synonyms, and 3) all primary research methods. 21 studies were included, five cluster randomised controlled trials (cRCTs), one randomised controlled trial (RCT), 11 intervention studies, also included were three modelling studies and one survey. 19 out of 21 included studies were published between 2009 and 2020. 18 of the studies were conducted in the context of the Regional Initiative. Effects of IRS on vector populations are positive, confirmed in terms of effectiveness and by the availability of studies. Deltamethrin and alpha-Cypermethrin reduce total sandfly counts, and/or Phlebotomus argentipes counts by up to 95% with an effect of a minimum of one month. Prolonged effects are not regularly seen. DDT has been used in India only: whereas in the 1990s a good effect could be measured, this effect waned over time. Two intervention studies, embedded in larger programmes in 2019 and 2020, replaced DDT with alpha-Cypermethrin throughout the study. Combinations of different interventions are not systematically researched, however showing some promising results, for example for the combination of IRS and Temephos. Constant monitoring of insecticide resistancies and quality delivery of IRS are confirmed as key issues for programmes. No human transmission data are available to directly relate an effect of IRS–although modelling studies confirm the effect of IRS on human transmission. Concluding, IRS continues to be an effective intervention for Phlebotomus argentipes control. Delivery requires constant monitoring and quality assurance. Further studies need to assess IRS in different geographical areas affected by VL and combinations of interventions.

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Kujawa, M. "DDT and its Derivatives - Environmental Aspects. Environmental Health Criteria 83.98 Seiten, 2 Abb., 7 Tab., World Health Organization, Geneva 1989. Preis: 13, - Swfr." Food / Nahrung 35, n.º 1 (1991): 114. http://dx.doi.org/10.1002/food.19910350141.

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Moody, Richard P. y Brita Nadeau. "EFFECT OF THE MOSQUITO REPELLENT DEET AND LONG-WAVE ULTRAVIOLET RADIATION ON PERMEATION OF THE HERBICIDE 2,4-D AND THE INSECTICIDE DDT IN NATURAL RUBBER GLOVES". American Industrial Hygiene Association Journal 53, n.º 7 (julio de 1992): 436–41. http://dx.doi.org/10.1080/15298669291359915.

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29

Bozhao, Xu, Xiao Xianqi, R. H. Webber y J. D. Lines. "Comparison of the effect of insecticide-treated bed nets and DDT residual spraying on the prevalence of malaria transmitted by Anopheles anthropophagus in China". Transactions of the Royal Society of Tropical Medicine and Hygiene 92, n.º 2 (marzo de 1998): 135–36. http://dx.doi.org/10.1016/s0035-9203(98)90719-2.

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30

Djouaka, Rousseau, Romaric Akoton, Genevieve M. Tchigossou, Seun M. Atoyebi, Helen Irving, Michael O. Kusimo, Innocent Djegbe et al. "Mapping the distribution of Anopheles funestus across Benin highlights a sharp contrast of susceptibility to insecticides and infection rate to Plasmodium between southern and northern populations". Wellcome Open Research 1 (14 de diciembre de 2016): 28. http://dx.doi.org/10.12688/wellcomeopenres.10213.1.

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Background. Malaria remains an important public health issue in Benin, with Anopheles gambiae s.l. and Anopheles funestus s.s being the predominant vectors. This study was designed to generate information on An. funestus distribution, molecular speciation, Plasmodium infection rate and insecticide susceptibility status across Benin. Methods. Mosquito samples were collected from December 2014 to January 2016 in 46 localities in Benin. These samples were mapped and An. funestus collected were speciated to the molecular level. Plasmodium infection rate was determined using a Taqman assay and susceptibility to insecticides was assessed using the WHO guidelines. The genotyping of the L119F- Gste2 mutation was also carried out. Results. An. funestus was found in 8 out of the 46 localities surveyed with a high presence in Tanongou (wet Sudanese ecological zone), Kpome, Doukonta and Pahou (sub-equatorial ecological zone). Molecular identifications revealed that only An. funestus s.s was present in southern Benin, whereas in Tanongou (northern Benin) An. funestus s.s. and An. leesoni were found in sympatry at proportions of 77.7% and 22.3% respectively. Plasmodium infection rate of An. funestus was higher in southern Benin at a range of 13 to 18% compared to 5.6% recorded in Tanongou. High DDT (8±0.5%) and permethrin (11±0.5%) resistance were observed in Doukonta, Kpome and Pahou, contrasting with relatively low resistance profiles: mortality-DDT=90±3.18% and mortality-permethrin=100% in Tanongou. Genotyping analysis revealed high frequency of the resistant 119F allele in the South (Kpome and Doukonta) compared to the North (Tanongou). Discussion and Conclusion. The high presence of An. funestus in the South compared to the North could be due to favorable environmental and climatic conditions found in both regions. A significant Plasmodium infection rate was recorded across the country. A high resistance profile was recorded in the southern Benin; this raises the need for further investigations on resistance selection factors.

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31

Djouaka, Rousseau, Romaric Akoton, Genevieve M. Tchigossou, Seun M. Atoyebi, Helen Irving, Michael O. Kusimo, Innocent Djegbe et al. "Mapping the distribution of Anopheles funestus across Benin highlights a sharp contrast of susceptibility to insecticides and infection rate to Plasmodium between southern and northern populations". Wellcome Open Research 1 (3 de marzo de 2017): 28. http://dx.doi.org/10.12688/wellcomeopenres.10213.2.

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Background. Malaria remains an important public health issue in Benin, with Anopheles gambiae s.l. and Anopheles funestus s.s being the predominant vectors. This study was designed to generate information on An. funestus distribution, molecular speciation, Plasmodium infection rate and insecticide susceptibility status across Benin. Methods. Mosquito samples were collected from December 2014 to January 2016 in 46 localities in Benin. These samples were mapped and An. funestus collected were speciated to the molecular level. Plasmodium infection rate was determined using a Taqman assay and susceptibility to insecticides was assessed using the WHO guidelines. The genotyping of the L119F- Gste2 mutation was also carried out. Results. An. funestus was found in 8 out of the 46 localities surveyed with a high presence in Tanongou (wet Sudanese ecological zone), Kpome, Doukonta and Pahou (sub-equatorial ecological zone). Molecular identifications revealed that only An. funestus s.s was present in southern Benin, whereas in Tanongou (northern Benin) An. funestus s.s. and An. leesoni were found in sympatry at proportions of 77.7% and 22.3% respectively. Plasmodium infection rate of An. funestus was higher in southern Benin at a range of 13 to 18% compared to 5.6% recorded in Tanongou. High DDT (8±0.5%) and permethrin (11±0.5%) resistance were observed in Doukonta, Kpome and Pahou, contrasting with relatively low resistance profiles: mortality-DDT=90±3.18% and mortality-permethrin=100% in Tanongou. Genotyping analysis revealed high frequency of the resistant 119F allele in the South (Kpome and Doukonta) compared to the North (Tanongou). Discussion and Conclusion. The high presence of An. funestus in the South compared to the North could be due to favorable environmental and climatic conditions found in both regions. A significant Plasmodium infection rate was recorded across the country. A high resistance profile was recorded in the southern Benin; this raises the need for further investigations on resistance selection factors.

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MONTAGUE, PETER. "Research Ethics and the Precautionary Principle: Marching toward Environmental Decay". Cambridge Quarterly of Healthcare Ethics 12, n.º 4 (7 de agosto de 2003): 466–67. http://dx.doi.org/10.1017/s0963180103124176.

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I recently read through the most recent 24 issues of Environmental Health Perspectives—the National Institutes of Health journal of, among other issues, scientific research into how environmental contaminants impact animal and human health. It is a catalog of horrors from a public health perspective. Fish and frogs with their sex scrambled; deformed frogs with altered hormone levels in their blood; a nearly threefold increase in birth defects among Minnesota farm children exposed to pesticides; 2,4-D exposure reducing hormone levels in men; insignificant levels of four environmental chemicals adding up to a significant dose; a third study reconfirming a 50% sperm decline in U.S. men, 1934–1996; phthalates elevated in the blood of Puerto Rican girls developing breasts before they are 8; some 6,000 chemicals declared candidates for study as hormone disrupters (selected by computer from a universe of 58,000 chemicals for “most” of which we have “no biologic data”); children living near incinerators having delayed sexual development; hypospadias linked to organochlorine levels in the blood of mink, otter, and polar bears; and “No living organism may be considered DDT-free.” Nothing definitive, but it all suggests that things are tending in a direction that is perfectly awful.

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van den Berg, Henk, Raman Velayudhan y Rajpal S. Yadav. "Management of insecticides for use in disease vector control: Lessons from six countries in Asia and the Middle East". PLOS Neglected Tropical Diseases 15, n.º 4 (30 de abril de 2021): e0009358. http://dx.doi.org/10.1371/journal.pntd.0009358.

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Interventions to control the vectors of human diseases, notably malaria, leishmaniasis and dengue, have relied mainly on the action of chemical insecticides. However, concerns have been raised regarding the management of insecticides in vector-borne disease-endemic countries. Our study aimed to analyze how vector control insecticides are managed in selected countries to extract lessons learned. A qualitative analysis of the situation of vector control insecticides management was conducted in six countries. Multi-stakeholder meetings and key informer interviews were conducted on aspects covering the pesticide lifecycle. Findings were compared and synthesized to extract lessons learned. Centrally executed guidelines and standards on the management of insecticides offered direction and control in most malaria programs, but were largely lacking from decentralized dengue programs, where practices of procurement, application, safety, storage, and disposal were variable between districts. Decentralized programs were better at facilitating participation of stakeholders and local communities and securing financing from local budgets. However, little coordination existed between malaria, visceral leishmaniasis and dengue programs within countries. Entomological capacity was concentrated in malaria programs at central level, while dengue and visceral leishmaniasis programs were missing out on expertise. Monitoring systems for insecticide resistance in malaria vectors were rarely used for dengue or visceral leishmaniasis vectors. Strategies for insecticide resistance management, where present, did not extend across programs or sectors in most countries. Dengue programs in most countries continued to rely on space spraying which, considering the realities on the ground, call for revision of international guidelines. Vector control programs in the selected countries were confronted with critical shortcomings in the procurement, application, safety measures, storage, and disposal of vector control insecticides, with implications for the efficiency, effectiveness, and safety of vector control. Further international support is needed to assist countries in situation analysis, action planning and development of national guidelines on vector control insecticide management.

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Bizhannia, Alireza, Keyvan Etebari, Alireza Seidavi y Seyed Ziaeddin Mirhosseini. "The effect of a pesticide on mulberry silkworm Bombyx mori (Lep.: Bombycidae) larvae". Proceedings of the British Society of Animal Science 2007 (abril de 2007): 162. http://dx.doi.org/10.1017/s1752756200020652.

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Environmental pollutants, like pesticides, have been destructive on different aspects of life. Silkworm, as a beneficial insect, is no exception to this matter. Due to this, many problems have appeared in sericulture because of pesticide applications to cultivations, especially when mulberry trees grow next to cultivated plants. Many studies that have focused on the effect of insecticides on B. mori deal with toxicity, retardation of development and growth, fecundity, mortality, food utilization and economic parameters (Vassarmidaki et al., 2000). However, between these studies a few documents focused on the effect of fungicide residue on silkworm growth and performances (Dutta et al., 2003). Sik et al (1976) reported that more than 1.4% of yield reduction in sericulture is due to side effect of pesticide application. 49.4% was due to the application of different pesticides in rice filed, 21.2% in fruit garden and 12.3% in olericulture. Therefore, the present investigation deals effects of long term application of systemic insecticide, Oxydemeton-methyl(metasystox R) on some biological performance of silkworm. Because metasystox has just recently used to against of mulberry thrips in sericulture and it is necessary to study different side effects of this insecticide on silkworm.

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Lucas, Keira J., Rachel B. Bales, Kaci McCoy y Caroline Weldon. "Oxidase, Esterase, and KDR-Associated Pyrethroid Resistance in Culex quinquefasciatus Field Collections of Collier County, Florida". Journal of the American Mosquito Control Association 36, n.º 1 (1 de marzo de 2020): 22–32. http://dx.doi.org/10.2987/19-6850.1.

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ABSTRACT In several insect species, resistance to pyrethroids and DDT (dichlorodiphenyltrichloroethane) is linked to point mutations in the voltage-gated sodium channel (VGSC) gene. Pyrethroid-based insecticides prolong the opening of sodium channels, causing paralysis known as a “knockdown” effect before mortality occurs. Point mutations in the VGSC gene result in decreased pyrethroid binding and reduced sensitivity to the insecticide—this resistance mechanism is known as knockdown resistance (kdr) as insects do not die but recover from paralysis with time. In Culex mosquito species loss of target site sensitivity to pyrethroids is linked to a number of substitutions, one of which is leucine (L) to phenylalanine (F) at residue 1014 (L1014F) in the VGSC gene. Here we report the identification of kdr-associated pyrethroid resistance and developing resistance in Cx. quinquefasciatus field collections from Collier County, FL. Evaluation of position 1014 of the VGSC in Cx. quinquefasciatus collections from 7 locations in Collier County, FL, revealed a wide range of genotypes from one part of the district to the other. Centers for Disease Control and Prevention bottle bioassay, linear regression analysis, and cage trial evaluations suggest that the L1014F mutation plays a role, at least in part, to the pyrethroid resistance status of Cx. quinquefasciatus collected in Collier County, FL. Furthermore, we identified resistance attributed to both oxidase and esterase activity, indicating that multiple mechanisms are responsible for pyrethroid resistance in Collier County Cx. quinquefasciatus.

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Silva, Juan J., Cedric N. Kouam y Jeffrey G. Scott. "Levels of cross-resistance to pyrethroids conferred by the Vssc knockdown resistance allele 410L+1016I+1534C in Aedes aegypti". PLOS Neglected Tropical Diseases 15, n.º 7 (12 de julio de 2021): e0009549. http://dx.doi.org/10.1371/journal.pntd.0009549.

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Aedes aegypti is a primary vector of viral pathogens and is responsible for millions of human infections annually that represent critical public health and economic costs. Pyrethroids are one of the most commonly used classes of insecticides to control adult A. aegypti. The insecticidal activity of pyrethroids depends on their ability to bind and disrupt the voltage-sensitive sodium channel (VSSC). In mosquitoes, a common mechanism of resistance to pyrethroids is due to mutations in Vssc (hereafter referred as knockdown resistance, kdr). In this study, we found that a kdr (410L+V1016I+1534C) allele was the main mechanism of resistance in a pyrethroid-resistant strain of A. aegypti collected in Colombia. To characterize the level of resistance these mutations confer, we isolated a pyrethroid resistant strain (LMRKDR:RK, LKR) that was congenic to the susceptible Rockefeller (ROCK) strain. The full-length cDNA of Vssc was cloned from LKR and no additional resistance mutations were present. The levels of resistance to different pyrethroids varied from 3.9- to 56-fold. We compared the levels of resistance to pyrethroids, DCJW and DDT between LKR and what was previously reported in two other congenic strains that share the same pyrethroid-susceptible background (the ROCK strain), but carry different kdr alleles (F1534C or S989P + V1016G). The resistance conferred by kdr alleles can vary depending on the stereochemistry of the pyrethroid. The 410L+1016I+1534C kdr allele does not confer higher levels of resistance to six of ten pyrethroids, relative to the 1534C allele. The importance of these results to understand the evolution of insecticide resistance and mosquito control are discussed.

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Goulding, Roy. "Book Reviews : DDT and its Derivatives — Environmental Aspects (No. 83). Published by WHO, Geneva, 1989. Price Sw fr. 13. Paperback. Pp 98. ISBN 92 4 154283 7". Journal of the Royal Society of Health 110, n.º 1 (febrero de 1990): 38. http://dx.doi.org/10.1177/146642409011000126.

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Damon, A. "A review of the biology and control of the coffee berry borer, Hypothenemus hampei (Coleoptera: Scolytidae)". Bulletin of Entomological Research 90, n.º 6 (diciembre de 2000): 453–65. http://dx.doi.org/10.1017/s0007485300000584.

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AbstractThe coffee berry borer, Hypothenemus hampei Ferrari, is a serious problem for the majority of the world‘s coffee growers and has proved to be one of the most intractable of present day pests. Despite a great deal of research, control still depends largely on the application of the organochlorine insecticide endosulfan, which is damaging to the environment, or a series of cultural and biological control methods which give variable and unpredictable results. This review summarizes the most important aspects of the biology and ecology of H. hampei and its control and identifies weak points in the knowledge about this pest. Emphasis is placed upon an analysis of the non-chemical control methods available and suggestions are offered for novel ecological and environmental factors worthy of further research, in the search for viable and sustainable control methods.

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Monroy, Carlota, Dulce Maria Bustamante, Sandy Pineda, Antonieta Rodas, Xochitl Castro, Virgilio Ayala, Javier Quiñónes y Bárbara Moguel. "House improvements and community participation in the control of Triatoma dimidiata re-infestation in Jutiapa, Guatemala". Cadernos de Saúde Pública 25, suppl 1 (2009): S168—S178. http://dx.doi.org/10.1590/s0102-311x2009001300016.

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The deterioration or absence of plaster walls in houses and poor hygienic conditions are the most important risk factors for indoor Triatoma dimidiata infestation in Guatemala. A cross-disciplinary study was conducted addressing T. dimidiata infestation, household hygiene, and housing construction. The study focused on local materials and cultural aspects (including gender roles) that could lead to long-term improvements in wall construction. A new plaster mix for walls was developed on the basis of laboratory studies on construction materials recommended by local villagers. Four villages with persistent (post-spraying) T. dimidiata infestation were studied. In two villages, an ecosystem approach was implemented, and the homeowners conducted wall improvements and household sanitation with the support of the interdisciplinary team (the ecosystem intervention). In the other two villages, a vector control approach based on insecticide spraying was adopted (traditional intervention). Both interventions were associated with a reduction in T. dimidiata infestation, but only the ecosystem approach produced important housing improvements (sanitation and wall construction) capable of preventing T. dimidiata re-infestation in the long term.

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Sheikh, Ishfaq Ahmad y Mohd Amin Beg. "Structural Aspects of Potential Endocrine-Disrupting Activity of Stereoisomers for a Common Pesticide Permethrin against Androgen Receptor". Biology 10, n.º 2 (11 de febrero de 2021): 143. http://dx.doi.org/10.3390/biology10020143.

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Endocrine-disrupting chemicals (EDCs) are a serious global public health and environmental concern. Pyrethroids are insecticide chemicals that are extensively used for crop protection and household purposes but have been identified as EDCs. On account of their ubiquitous environmental presence, human exposure occurs via food, dermal, or inhalation routes and is associated with health problems, including reproductive dysfunction. Permethrin is the most commonly used pyrethroid, and with two chiral centers in its structure, it has four stereoisomeric forms (two enantiomer pairs), i.e., permethrin (1R,3R)-cis, permethrin (1R,3S)-trans, permethrin (1S,3S)-cis, and permethrin (1S,3R)-trans. The current study was performed for predicting the potential endocrine-disrupting activity of the aforementioned four stereoisomers of permethrin against the androgen receptor (AR). The structural binding characterization and binding energy estimations in the AR binding pocket were done using induced fit docking. The structural binding data indicated that all stereoisomers were placed stably in the AR binding pocket and that the estimated binding energy values were comparable to the AR native ligand, except for permethrin (1S,3S)-cis. Furthermore, the commonality in the amino acid interactions to that of the AR native ligand and the binding energy values suggested the potential AR-disrupting activity of all the stereoisomers; however, stereoselective differences were not observed. Taken together, the results suggest that human exposure to permethrin, either as a racemate mixture or in individual stereoisomer form, could potentially interfere with AR function, which may lead to male reproductive dysfunction.

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Goddard, Jerome y Wendy C. Varnado. "Disaster Vector Control in Mississippi After Hurricane Katrina: Lessons Learned". Journal of the American Mosquito Control Association 36, n.º 2s (1 de junio de 2020): 56–60. http://dx.doi.org/10.2987/18-6870.1.

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ABSTRACT Hurricane Katrina devastated the Mississippi Gulf Coast on August 29, 2005, causing an ecological disaster. Mississippi State Department of Health (MSDH) entomologists established a vector control program in affected areas with the following objectives: 1) helping local vector control agencies reestablish services, 2) performing mosquito surveillance, and 3) establishing mosquito larviciding and adulticiding where necessary. The MSDH personnel also helped write Action Request Forms requesting assistance from the Federal Emergency Management Agency (FEMA) for increased ground spraying in the 6 lower counties. Mosquito surveillance was conducted daily for 2 wk after the storm, then weekly for another month. Sanitation lagged, with people using makeshift latrines or simply piles of rubbish for bathrooms. Filth flies contaminated food and food surfaces. Responders lived in tent cities, many allowing filth fly access. Approximately 2 wk after hurricane landfall, due to increasing mosquito numbers, MSDH entomologists requested FEMA for an aerial spraying of insecticide to reduce nuisance mosquito biting in the area. A private vendor made 1 application of naled (Dibrom®) insecticide in the 3 coastal counties, yielding over 90% control in entire counties in 1 night. No complaints or medical or environmental problems from the increased ground spraying and aerial spraying were reported. Overall, important lessons in disaster vector control were learned, including how to work effectively with Centers for Disease Control, FEMA, and the US Public Health Service personnel, how to manage the public relations/educational aspects, and how to avoid or mitigate political interference in the disaster response.

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Mörtl, Mária, Ágnes Vehovszky, Szandra Klátyik, Eszter Takács, János Győri y András Székács. "Neonicotinoids: Spreading, Translocation and Aquatic Toxicity". International Journal of Environmental Research and Public Health 17, n.º 6 (18 de marzo de 2020): 2006. http://dx.doi.org/10.3390/ijerph17062006.

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Various environmental and ecotoxicological aspects related to applications of neonicotinoid insecticides are assessed. Dosages of neonicotinoids applied in seed coating materials were determined and are compared to other applications (spray and granule). Environmental levels in soils and affecting factors in translocation are discussed. Excretion of neonicotinoids via guttation from coated maize seeds up to two months upon emergence, as well as cross-contamination of plants emerged from non-coated seeds or weeds nearby have been demonstrated. Contamination of surface waters is discussed in scope of a worldwide review and the environmental fate of the neonicotinoid active ingredients and the formulating surfactant appeared to be mutually affected by each other. Toxicity of neonicotinoid active ingredients and formulations on Daphnia magna completed with some investigations of activity of the detoxifying glutathione S-transferase enzyme demonstrated the modified toxicity due to the formulating agents. Electrophysiological results on identified central neurons of the terrestrial snail Helix pomatia showed acetylcholine antagonist (inhibitory) effects of neonicotinoid insecticide products, but no agonist (ACh-like) effects were recorded. These data also suggested different molecular targets (nicotinergic acetylcholine receptors and acetylcholine esterase enzyme) of neonicotinoids in the snail central nervous system.

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Smith, Letícia B., Juan J. Silva, Connie Chen, Laura C. Harrington y Jeffrey G. Scott. "Fitness costs of individual and combined pyrethroid resistance mechanisms, kdr and CYP-mediated detoxification, in Aedes aegypti". PLOS Neglected Tropical Diseases 15, n.º 3 (24 de marzo de 2021): e0009271. http://dx.doi.org/10.1371/journal.pntd.0009271.

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Background Aedes aegypti is an important vector of many human diseases and a serious threat to human health due to its wide geographic distribution and preference for human hosts. A. aegypti also has evolved widespread resistance to pyrethroids due to the extensive use of this insecticide class over the past decades. Mutations that cause insecticide resistance result in fitness costs in the absence of insecticides. The fitness costs of pyrethroid resistance mutations in A. aegypti are still poorly understood despite their implications for arbovirus transmission. Methodology/Principle findings We evaluated fitness based both on allele-competition and by measuring specific fitness components (i.e. life table and mating competition) to determine the costs of the different resistance mechanisms individually and in combination. We used four congenic A. aegypti strains: Rockefeller (ROCK) is susceptible to insecticides; KDR:ROCK (KR) contains only voltage-sensitive sodium channel (Vssc) mutations S989P+V1016G (kdr); CYP:ROCK (CR) contains only CYP-mediated resistance; and CYP+KDR:ROCK (CKR) contains both CYP-mediated resistance and kdr. The kdr allele frequency decreased over nine generations in the allele-competition study regardless of the presence of CYP-mediated resistance. Specific fitness costs were variable by strain and component measured. CR and CKR had a lower net reproductive rate (R0) than ROCK or KR, and KR was not different than ROCK. There was no correlation between the level of permethrin resistance conferred by the different mechanisms and their fitness cost ratio. We also found that CKR males had a reduced mating success relative to ROCK males when attempting to mate with ROCK females. Conclusions/Significance Both kdr and CYP-mediated resistance have a fitness cost affecting different physiological aspects of the mosquito. CYP-mediated resistance negatively affected adult longevity and mating competition, whereas the specific fitness costs of kdr remains elusive. Understanding fitness costs helps us determine whether and how quickly resistance will be lost after pesticide application has ceased.

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Yousefi, Fatemeh, Gholamreza Asadikaram, Saeid Karamouzian, Moslem Abolhassani, Vahid Moazed y Mohammad Hadi Nematollahi. "MGMT methylation alterations in brain cancer following organochlorine pesticides exposure". Environmental Health Engineering and Management 8, n.º 1 (27 de febrero de 2021): 47–53. http://dx.doi.org/10.34172/ehem.2021.07.

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Background: Alterations in the methylation levels of tumor suppressor genes are considered as one of the essential aspects of malignancies. The present study explored the association of O6-methylguanine-DNA methyltransferase (MGMT) gene promoter methylation, as a tumor suppressor, with some organochlorine pesticides (OCPs) in primary brain tumor (PBT) patients. Methods: The present study was conducted on a total of 73 PBT patients. The patients’ serum was analyzed using gas chromatography for seven OCP derivatives. The methylation-specific PCR (MSP) method was also used to determine the methylation status of the MGMT promoter. Results: The current findings demonstrated that the methylation of MGMT promoter occurred in 22 out of 34 glioma cases (64%), but in only one out of 35 meningioma cases. No MGMT promoter methylation was observed in other PBT, hemangioma, and anaplastic medulloblastoma stages. Besides, there were significant associations between MGMT methylation and γ-HCH (odds ratio [OR]: 1.50; 95% CI: 1.03- 2.40, P=0.04), 4,4DDE (OR: 1.44; 95% CI: 1.01- 2.05, P=0.02), 2,4 DDT (OR: 1.23; CI: 1.04- 1.45, P=0.03), and 4,4DDT (OR: 1.46; CI: 1.23- 2.15, P=0.02) in glioma patients. Conclusion: The results of the study suggested that the hypermethylation of the MGMT promoter in glioma patients is associated with increased OCPs in their serum, especially γ- HCH, 4,4DDE, 2,4DDT, and 4,4DDT. Moreover, it may lead to the hypermethylation of the MGMT promoter gene. Hence, it can be concluded that exposure to OCPs may potentially induce glioma.

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Quaresima, Virginia, Tsiri Agbenyega, Bismark Oppong, Julia Ann D. A. Awunyo, Priscilla Adu Adomah, Eunice Enty, Francesco Donato y Francesco Castelli. "Are Malaria Risk Factors Based on Gender? A Mixed-Methods Survey in an Urban Setting in Ghana". Tropical Medicine and Infectious Disease 6, n.º 3 (2 de septiembre de 2021): 161. http://dx.doi.org/10.3390/tropicalmed6030161.

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Malaria still represents one of the most debilitating and deadly diseases in the world. It has been suggested that malaria has different impacts on women and men due to both social and biological factors. A gender perspective is therefore important to understand how to eliminate malaria. This study aimed to investigate malaria from a gender perspective in a non-for-profit private health facility, HopeXchange Medical Centre, based in Kumasi (Ghana). A sequential mixed-methods design, comprising quantitative and qualitative methods, was used. This study found low ownership (40%) and use (19%) of insecticide-treated nets (ITNs). Most malaria cases were women (62%), who were less educated and had more external risk factors associated with infection. Our study reported a trend of preferring malaria self-medication at home, which was practiced mostly by men (43%). Our data suggest that women are more likely to be exposed to malaria infections than men, especially due to their prolonged exposure to mosquito bites during the most dangerous hours. Our study highlighted the need for future malaria control policies to be more focused on social and behavioral aspects and from a gender perspective.

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Didović, Mirna Petković, Tomasz Kowalkowski y Dalibor Broznić. "Emerging Contaminant Imidacloprid in Mediterranean Soils: The Risk of Accumulation Is Greater than the Risk of Leaching". Toxics 10, n.º 7 (30 de junio de 2022): 358. http://dx.doi.org/10.3390/toxics10070358.

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Imidacloprid (IMI) is an extensively used neonicotinoid insecticide whose occurrence in the environment is a worldwide problem. Its sorption/transport properties are recognized as one of the key knowledge gaps hindering policymaking regarding its international routine monitoring in soils. Therefore, we studied IMI transport behaviour in Croatian Mediterranean soils using column experiments. Breakthrough curves were analysed using the two-site adsorption model and compared against dimethoate (DIM). Transport parameters were correlated to soil physicochemical properties. The results indicate that IMI shows a high degree of preference for soil organic matter over any other soil constituent. For IMI, the clay did not exhibit any sorption activity, while hematite did act as an active sorbent. Contrarily, hematite increased the leachability of DIM by blocking the active sorption sites on clay platelets. Both hematite and clay sorption acted as type-2 (i.e., rate-limiting) sites. In all soils, IMI exhibited lower short-term leachability than DIM. Combined with a body of data concerning other aspects of IMI environmental behaviour, the results indicate that the risk of accumulation of IMI in the soil is greater than the risk of contamination by leaching. Thus, continuous monitoring of IMI in soils should be incorporated into future soil health protection programs.

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Xue, Kai, Raquel C. Serohijos, Medha Devare y Janice E. Thies. "Decomposition Rates and Residue-Colonizing Microbial Communities ofBacillus thuringiensisInsecticidal Protein Cry3Bb-Expressing (Bt) and Non-Bt Corn Hybrids in the Field". Applied and Environmental Microbiology 77, n.º 3 (10 de diciembre de 2010): 839–46. http://dx.doi.org/10.1128/aem.01954-10.

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ABSTRACTDespite the rapid adoption of crops expressing the insecticidal Cry protein(s) fromBacillus thuringiensis(Bt), public concern continues to mount over the potential environmental impacts. Reduced residue decomposition rates and increased tissue lignin concentrations reported for some Bt corn hybrids have been highlighted recently as they may influence soil carbon dynamics. We assessed the effects of MON863 Bt corn, producing the Cry3Bb protein against the corn rootworm complex, on these aspects and associated decomposer communities by terminal restriction fragment length polymorphism (T-RFLP) analysis. Litterbags containing cobs, roots, or stalks plus leaves from Bt and unmodified corn with (non-Bt+I) or without (non-Bt) insecticide applied were placed on the soil surface and at a 10-cm depth in field plots planted with these crop treatments. The litterbags were recovered and analyzed after 3.5, 15.5, and 25 months. No significant effect of treatment (Bt, non-Bt, and non-Bt+I) was observed on initial tissue lignin concentrations, litter decomposition rate, or bacterial decomposer communities. The effect of treatment on fungal decomposer communities was minor, with only 1 of 16 comparisons yielding separation by treatment. Environmental factors (litterbag recovery year, litterbag placement, and plot history) led to significant differences for most measured variables. Combined, these results indicate that the differences detected were driven primarily by environmental factors rather than by any differences between the corn hybrids or the use of tefluthrin. We conclude that the Cry3Bb corn tested in this study is unlikely to affect carbon residence time or turnover in soils receiving these crop residues.

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Turner, D. A. y R. Brightwell. "An evaluation of a sequential aerial spraying operation against Glossina pallidipes Austen (Diptera: Glossinidae) in the Lambwe Valley of Kenya: aspects of post-spray recovery and evidence of natural population regulation". Bulletin of Entomological Research 76, n.º 2 (junio de 1986): 331–49. http://dx.doi.org/10.1017/s0007485300014802.

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AbstractAn attempt to eradicate Glossina pallidipes Austen from the Lambwe Valley of western Kenya by sequential aerial application of endosulfan aerosol spray is described. The operation was ultimately unsuccessful, even after nine sprays of relatively heavy dosages of insecticide. Survivors were present throughout after each spray, and females mated and bred between sprays. The population was reduced by over 99·9% in main habitats of thicket and woodland and by about 90% in conifer plantation. The outcome of a model of spray effectiveness suggested, however, that the final reduction in population size was the cumulative effect of only about a 90% kill per spray application. Post-spray monitoring showed that the tsetse population in thicket returned to its pre-spray level in little more than 12 months and became stabilized thereafter. Elsewhere, recovery was much slower and more variable. Evidence was found for population regulation by density-dependent emigration of flies. Calculations of population growth rate gave an instantaneous rate of increase of 0·0148/day, equivalent to a finite rate of increase of 1·568/month or a doubling time of 47 days. This permitted a 90-fold increase in population size over a ten-month period of unrestricted growth. The failure to achieve eradication is discussed in terms of certain operational shortcomings and environmental constraints which exist in the Lambwe Valley.

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Moza, Sotiria, Georgios M. Hadjigeorgiou, Nikolaos Scarmeas, Efthimios Dardiotis, Mary Yannakoulia y Mary H. Kosmidis. "Pesticide Use and its Effects on Daily Functioning among Elderly Farmers". Journal of Biomedical Research & Environmental Sciences 2, n.º 10 (octubre de 2021): 905–14. http://dx.doi.org/10.37871/jbres1330.

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Background: Poor pesticide handling practices are recorded on a regular basis in Greece, where the average farmer is elderly. This raises concerns regarding their compliance with pesticide regulations and the associated health implications. Our purpose in undertaking the present study was to examine elderly farmers’ attitudes regarding pesticide handling and safety issues, as well as, the potential link between pesticide exposure and daily functioning capacity. Methods: Participants were 1443 elderly individuals, 276 of whom reported long-term, direct exposure to pesticides (spraying in gardens, open fields, and/or a greenhouse). Several aspects of pesticide handling were gleaned via a self-report questionnaire. Ability to perform everyday tasks was assessed with the Blessed Dementia Rating Scale. Results: On average, participants were not consistent with respect to safety practices. Half could not recall the specific brand names of the pesticides they used and 47.5% reported using chemical cocktails, often exceeding the maximum recommended frequency of applications per year. In many cases, they reported application of banned pesticides, such as DDT, and more than half reported applying pesticides without protective equipment. Analyses showed that exposure to pesticides was associated with impaired everyday functioning (OR = 1.16; 95%, CI = 1.04-1.28) and specifically, with an inability to interpret surroundings and recall recent events, a tendency to dwell on the past and changes in bladder-sphincter control. Conclusion: We found poor awareness and adherence to safety practices regarding pesticide use among elderly farmers, as well as an association between pesticide use and everyday functioning. Relevant health and environmental implications are discussed.

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Kotelevych, V. A. "Veterinary and sanitary assessment of quality and safety of meat and meat products in the marshes of LLC “Riton” Vinnytsa". Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 20, n.º 88 (8 de septiembre de 2018): 24–28. http://dx.doi.org/10.32718/nvlvet8804.

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The purpose of our research was to study the environmental aspects of the quality and safety of meat and meat products in the conditions of Ltd “Ryton” Vinnytsya and the measures applied in this subsidiary for the observance of proper hygienic and production practices (GHP/GMP) in their production as a guarantor of environmental security. The results of the veterinary and sanitary estimation of meat and meat products are reported according to the data of the reporting documentation of Ltd Ryton Vinnytsia (2015–2017), expert opinions of the Vinnytsia Regional State Veterinary Laboratory and Khmelnytsky Interdistrict State Laboratory of Veterinary Medicine (2018) on indicators security. The main cause of detoxification of byproducts was invasive and non-contagious diseases, in particular: liver – cirrhosis, fasciolysis and abscesses; kidneys – jade heart – traumatic pericarditis; udder – mastitis, lungs – pneumonia, pleurisy, aspiration with food and blood. According to safety indicators, there is a lack of pesticides (the mass fraction of HCCh gamma-isomer, DDT and its metabolites, DDVF, chlorophos, metaphys, carbophos, basidins), toxic elements (lead, cadmium, arsenic, mercury, copper, zinc), mycotoxins, antibiotics; Radiological and microbiological parameters in meat and meat samples were also within regulatory requirements and safe for consumption. The introduction of proper hygienic and production practices allowed Vinnitsa LLC to complete the certification process under the international program FSSC 22000 “Food Safety Management” and obtain the Certificates The HACCP Management System of CCM MS Standart HACCP and ISO 22000: 2007 Food Safety Management Systems, Requirements for any Organisation in the Food Chain. The performed researches prove the theoretical and practical justification of the necessity of monitoring research on the quality and safety of livestock products, the observance of proper hygienic and production practices (GHP/GMP) taking into account the international program FSSC 22000 “Food Safety Management”, – the need to strengthen preventive measures by doctors of veterinary medicine invasive and non-contagious diseases of cattle.

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