Artículos de revistas: "Trace metals"

1

Sheppard, Stephen C. "Biogeochemistry of Trace Metals". Journal of Environmental Quality 22, n.º 2 (abril de 1993): 381–82. http://dx.doi.org/10.2134/jeq1993.00472425002200020028x.

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2

Bhutta, Zulfiqar Ahmed. "The Nutritional Trace Metals". Maternal and Child Nutrition 2, n.º 2 (abril de 2006): 123. http://dx.doi.org/10.1111/j.1740-8709.2006.00041.x.

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3

Al-Saleh, Iman y Sami Al-Enazi. "Trace metals in lipsticks". Toxicological & Environmental Chemistry 93, n.º 6 (julio de 2011): 1149–65. http://dx.doi.org/10.1080/02772248.2011.582040.

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4

Arvanitoyannis, I. S. "The Nutritional Trace Metals". International Journal of Food Science and Technology 40, n.º 9 (noviembre de 2005): 1019–20. http://dx.doi.org/10.1111/j.1365-2621.2005.01001.x.

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5

Omanović, Dario y Marko Branica. "Pseudopolarography of trace metals". Journal of Electroanalytical Chemistry 543, n.º 1 (febrero de 2003): 83–92. http://dx.doi.org/10.1016/s0022-0728(02)01484-5.

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6

Arens, Ursula. "The Nutritional Trace Metals". Journal of Human Nutrition and Dietetics 18, n.º 6 (diciembre de 2005): 469–70. http://dx.doi.org/10.1111/j.1365-277x.2005.00651.x.

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7

Hirose, Katsumi. "Chemical speciation of trace metals in seawater: Implication of particulate trace metals". Marine Chemistry 28, n.º 4 (enero de 1990): 267–74. http://dx.doi.org/10.1016/0304-4203(90)90047-g.

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8

Agbugui, Marian y Grace Abe. "Analysis of Trace Metal Bioaccumulation in Fish and Man; Health Risk Impact". International Journal of Fisheries and Aquaculture Research 9, n.º 1 (15 de enero de 2023): 32–59. http://dx.doi.org/10.37745/ijfar.15/vol9n13259.

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Trace metals occur during natural processes and are also obtained during anthropogenic activities. Streams, lakes and rivers surrounded by farmlands engaged in the use of Trace metal-enriched fertilizers have shown a possible and positive correlation to the rise of Trace metals in the use of chemical, organic and water-soluble fertilizers for a long period. there is a tendency for high correlations of trace metals in source waters. Furthermore, the increasing level of trace metals in fish is alarming and has spurred scientists to make research on the dangers caused by the trace metals resulting in trace metal accumulation and bioaccumulation of life cells. This study aims at assessing the possible sources of trace metals in the aquatic environment, the impact of Trace metals in the aquatic environment, their bioaccumulation in fish and human health risk impact, negative effects in fish have been attributed to the accumulation of trace metals such as irritation of the gastrointestinal mucosa, nephritis, necrosis, neurological and behavioural disorders and death amongst others). The ingestion, absorption and uptake of trace metals in fish are usually toxic and result in harmful damage to the fish and fish life. Since most of the metals taken up are non-biodegradable, such metals can bioaccumulate and bio-magnify. Over time, the accumulated metals affect the growth and development stages of fish from the production of viable eggs, hatchability laval, fingerlings and juvenile life stages. This is so because the early life stages are more sensitive than during maturing and adulthood. In conclusion, negative results of the presence of trace metals and the effect of bioaccumulation and bio-magnification have been reviewed in this paper. This study recommends that the proper assessment and treatment of all forms of wastewater, agricultural waste, sewage, and industrial effluents be carried out before their discharge into the environment.

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9

Ryzhenko, Natalia O. "Metals Phytotoxicity Assessment and Classification". International Letters of Natural Sciences 73 (enero de 2019): 17–25. http://dx.doi.org/10.18052/www.scipress.com/ilns.73.17.

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In this paper, the influence of trace metals(Cd, Pb, Cu, Co, Ni, Zn) on plants of spring barley (Hordeum vulgare L.) was investigated in polluted sod podzolic sandy loam on layered glacial sands and calcareous deep chernozem on loamy loess soils. We propose to estimate the phytotoxicity with help of phytotoxicological classification. The phytotoxicological classification of trace metals gives the possibility to assess their hazard for plants. On the base of indicators such as: plant up-taking index (UI), phytoletal dose (PhLD50), Dipole moment (µ), Phyto Maximum Allowable Concentration (PMAC) a phytotoxicological classification of hazardous trace metals was suggested. The four classes of danger in phytotoxicological classification of hazardous trace metals were offered. According to phytotoxicological classification, Cd, Co, Ni belong to the first class of hazard, Cu – to second class of hazard, Zn – to third class of hazard, Pb – to fourth class of hazard. Phytotoxicological classification of hazardous trace metals gives the possibility to comprehensively estimate the danger of trace metals for plants as a biological object that plays a very important role in the life of ecosystem. This approach may be applied for another trace metals risk assessment for other plants.

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10

Ryzhenko, Natalia O. "Metals Phytotoxicity Assessment and Classification". International Letters of Natural Sciences 73 (28 de enero de 2019): 17–25. http://dx.doi.org/10.56431/p-y7xi95.

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In this paper, the influence of trace metals(Cd, Pb, Cu, Co, Ni, Zn) on plants of spring barley (Hordeum vulgare L.) was investigated in polluted sod podzolic sandy loam on layered glacial sands and calcareous deep chernozem on loamy loess soils. We propose to estimate the phytotoxicity with help of phytotoxicological classification. The phytotoxicological classification of trace metals gives the possibility to assess their hazard for plants. On the base of indicators such as: plant up-taking index (UI), phytoletal dose (PhLD50), Dipole moment (µ), Phyto Maximum Allowable Concentration (PMAC) a phytotoxicological classification of hazardous trace metals was suggested. The four classes of danger in phytotoxicological classification of hazardous trace metals were offered. According to phytotoxicological classification, Cd, Co, Ni belong to the first class of hazard, Cu – to second class of hazard, Zn – to third class of hazard, Pb – to fourth class of hazard. Phytotoxicological classification of hazardous trace metals gives the possibility to comprehensively estimate the danger of trace metals for plants as a biological object that plays a very important role in the life of ecosystem. This approach may be applied for another trace metals risk assessment for other plants.

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11

Facey, Jordan A., Simon C. Apte y Simon M. Mitrovic. "A Review of the Effect of Trace Metals on Freshwater Cyanobacterial Growth and Toxin Production". Toxins 11, n.º 11 (5 de noviembre de 2019): 643. http://dx.doi.org/10.3390/toxins11110643.

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Cyanobacterial blooms are becoming more common in freshwater systems, causing ecological degradation and human health risks through exposure to cyanotoxins. The role of phosphorus and nitrogen in cyanobacterial bloom formation is well documented and these are regularly the focus of management plans. There is also strong evidence that trace metals are required for a wide range of cellular processes, however their importance as a limiting factor of cyanobacterial growth in ecological systems is unclear. Furthermore, some studies have suggested a direct link between cyanotoxin production and some trace metals. This review synthesises current knowledge on the following: (1) the biochemical role of trace metals (particularly iron, cobalt, copper, manganese, molybdenum and zinc), (2) the growth limitation of cyanobacteria by trace metals, (3) the trace metal regulation of the phytoplankton community structure and (4) the role of trace metals in cyanotoxin production. Iron dominated the literature and regularly influenced bloom formation, with 15 of 18 studies indicating limitation or colimitation of cyanobacterial growth. A range of other trace metals were found to have a demonstrated capacity to limit cyanobacterial growth, and these metals require further study. The effect of trace metals on cyanotoxin production is equivocal and highly variable. Better understanding the role of trace metals in cyanobacterial growth and bloom formation is an essential component of freshwater management and a direction for future research.

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12

Haraldsson, Conny y Stig Westerlund. "Trace Metals in Anoxic Environment". Water Science and Technology 18, n.º 4-5 (1 de abril de 1986): 320. http://dx.doi.org/10.2166/wst.1986.0228.

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13

Sahan, Y. y F. Basoglu. "TRACE METALS IN OLIVE OIL". Acta Horticulturae, n.º 791 (junio de 2008): 719–23. http://dx.doi.org/10.17660/actahortic.2008.791.109.

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14

Douglas, M. A. y B. E. Gnade. "Photostimulated Removal of Trace Metals". Journal of The Electrochemical Society 138, n.º 9 (1 de septiembre de 1991): 2799–802. http://dx.doi.org/10.1149/1.2086059.

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15

McClain, Craig, Luis Marsano, Raymond Burk y Bruce Bacon. "Trace Metals in Liver Disease". Seminars in Liver Disease 11, n.º 04 (noviembre de 1991): 321–39. http://dx.doi.org/10.1055/s-2008-1040450.

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16

Oliveira Brett, Ana Maria, Christopher M. A. Brett, Frank-Michael Matysik y Silke Matysik. "Sonoelectrochemical analysis of trace metals". Ultrasonics Sonochemistry 4, n.º 2 (abril de 1997): 123–24. http://dx.doi.org/10.1016/s1350-4177(97)00015-1.

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17

Domen, RonaldE y WilliamH Roberts. "TRACE METALS AND PLASMA EXCHANGE". Lancet 328, n.º 8515 (noviembre de 1986): 1096. http://dx.doi.org/10.1016/s0140-6736(86)90489-7.

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18

Rainbow, Philip S. y David J. H. Phillips. "Cosmopolitan biomonitors of trace metals". Marine Pollution Bulletin 26, n.º 11 (noviembre de 1993): 593–601. http://dx.doi.org/10.1016/0025-326x(93)90497-8.

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19

Viarengo, Aldo. "Biochemical effects of trace metals". Marine Pollution Bulletin 16, n.º 4 (abril de 1985): 153–58. http://dx.doi.org/10.1016/0025-326x(85)90006-2.

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20

Thomas, F. G. "Trace metals in sea water". Marine Chemistry 16, n.º 1 (abril de 1985): 99. http://dx.doi.org/10.1016/0304-4203(85)90030-1.

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21

McClain, Craig J., Marion McClain, Shirish Barve y Maria G. Boosalis. "Trace metals and the elderly". Clinics in Geriatric Medicine 18, n.º 4 (noviembre de 2002): 801–18. http://dx.doi.org/10.1016/s0749-0690(02)00040-x.

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22

Lin, T. S., F. M. Shen, J. L. Chen y M. H. Yang. "Trace Metals in Candle Smoke". Bulletin of Environmental Contamination and Toxicology 70, n.º 1 (1 de enero de 2003): 182–87. http://dx.doi.org/10.1007/s00128-002-0173-8.

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23

Dailey, R., M. F. Raisbeck, R. Siemion y S. Wolff. "Trace Metals in Wyoming Fish". Bulletin of Environmental Contamination and Toxicology 74, n.º 6 (junio de 2005): 1078–83. http://dx.doi.org/10.1007/s00128-005-0691-2.

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24

Chester, Roy. "Trace metals in sea water". Chemical Geology 51, n.º 1-2 (octubre de 1985): 151–52. http://dx.doi.org/10.1016/0009-2541(85)90097-x.

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25

Falandysz, Jerzy. "Trace metals in squidIllex argentinus". Zeitschrift f�r Lebensmittel-Untersuchung und -Forschung 187, n.º 4 (octubre de 1988): 359–61. http://dx.doi.org/10.1007/bf01454428.

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26

Saltman, P. "Trace metals and human nutrition". Journal of Inorganic Biochemistry 36, n.º 3-4 (agosto de 1989): 344. http://dx.doi.org/10.1016/0162-0134(89)84574-x.

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27

Quek, Udo y J�rgen F�rster. "Trace metals in roof runoff". Water, Air, & Soil Pollution 68, n.º 3-4 (junio de 1993): 373–89. http://dx.doi.org/10.1007/bf00478464.

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28

Hendrix, Sophie, Nathalie Verbruggen, Ann Cuypers y Andreas J. Meyer. "Essential trace metals in plant responses to heat stress". Journal of Experimental Botany 73, n.º 6 (20 de noviembre de 2021): 1775–88. http://dx.doi.org/10.1093/jxb/erab507.

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Abstract Essential trace metals function as structural components or cofactors in many proteins involved in a wide range of physiological processes in plants. Hence, trace metal deficiency can significantly hamper plant growth and development. On the other hand, excess concentrations of trace metals can also induce phytotoxicity, for example via an enhanced production of reactive oxygen species. Besides their roles in plant growth under favourable environmental conditions, trace metals also contribute to plant responses to biotic and abiotic stresses. Heat is a stress factor that will become more prevalent due to increasing climate change and is known to negatively affect crop yield and quality, posing a severe threat to food security for future generations. Gaining insight into heat stress responses is essential to develop strategies to optimize plant growth and quality under unfavourable temperatures. In this context, trace metals deserve particular attention as they contribute to defence responses and are important determinants of plant nutritional value. Here, we provide an overview of heat-induced effects on plant trace metal homeostasis and the involvement of trace metals and trace metal-dependent enzymes in plant responses to heat stress. Furthermore, avenues for future research on the interactions between heat stress and trace metals are discussed.

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29

Higgins, HW y DJ Mackey. "Role of Ecklonia radiata (C. Ag.) J. Agardh in determining trace metal availability in coastal waters. I. Total trace metals". Marine and Freshwater Research 38, n.º 3 (1987): 307. http://dx.doi.org/10.1071/mf9870307.

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No seasonal variations were found in the concentrations of Zn, Cd, Cu, K, Ca, Mg and Na in the kelp E. radiata collected from the marine-dominated Port Hacking estuary on the east coast of Australia. Concentrations of Fe and Mn were about 60% higher in late summer. The relative distributions of all metals between different kelp tissues, however, showed no seasonal variation. Concentration factors (dry weight basis) for trace metals ranged from 2600 for Cu to 68 000 for Fe. With high biomasses common in macroalgal ecosystems, a large proportion of the non-sediment- bound trace metals can be associated with the macroalgae, which therefore act as substantial buffers for these elements. Metal concentration factors (Y, wet wt basis) were related to oceanic residence times (τ) by the equation log Y = -0.69 logτ + 5.4. The distribution of the aikaii and akaline earth metais (K, Ca, Mg and Na) was relativeiy uniform throughout the various kelp tissues. However, concentrations of Fe, Mn, Zn and Cd were significantly higher in the older extremities (holdfast and eroding tip) than in the meristematic region. Although the holdfast also had higher levels of Cu than the meristem, levels were lower in the eroding tip. The results suggest either a slow net intracellular accumulation of metals with time or an increase in potential metal- binding sites as the extremities senesce. Translocation and elimination of surplus metals through the eroding tip or holdfast was thought not to be important in E. radiata as metal concentrations did not differ between live and dead haptera of the holdfast. Likewise, storage of metals in either the holdfast or eroding tip was considered unlikely because of the constant relative tissue distribution throughout the year and lack of metal mobilization during periods of growth. Pretreatment of kelp tissue with an EDTA wash released about 90% of the total Zn and Cd, 25% of the Cu and 7% of the Fe, suggesting that a large proportion of the total kelp Zn and Cd is associated with the apparent free space (AFS). With rapid exchange between seawater and the AFS, E. radiata is therefore not generally useful as a sentinel accumulator species in pollution studies for assessing long term integrated changes of metals in the water column.

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30

Xiu, Junshan, Lili Dong, Hua Qin, Yunyan Liu y Jin Yu. "Investigation of the Matrix Effect on the Accuracy of Quantitative Analysis of Trace Metals in Liquids Using Laser-Induced Breakdown Spectroscopy with Solid Substrates". Applied Spectroscopy 70, n.º 12 (diciembre de 2016): 2016–24. http://dx.doi.org/10.1177/0003702816651889.

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The detection limit of trace metals in liquids has been improved greatly by laser-induced breakdown spectroscopy (LIBS) using solid substrate. A paper substrate and a metallic substrate were used as a solid substrate for the detection of trace metals in aqueous solutions and viscous liquids (lubricating oils) respectively. The matrix effect on quantitative analysis of trace metals in two types of liquids was investigated. For trace metals in aqueous solutions using paper substrate, the calibration curves established for pure solutions and mixed solutions samples presented large variation on both the slope and the intercept for the Cu, Cd, and Cr. The matrix effects among the different elements in mixed solutions were observed. However, good agreement was obtained between the measured and known values in real wastewater. For trace metals in lubricating oils, the matrix effect between the different oils is relatively small and reasonably negligible under the conditions of our experiment. A universal calibration curve can be established for trace metals in different types of oils. The two approaches are verified that it is possible to develop a feasible and sensitive method with accuracy results for rapid detection of trace metals in industrial wastewater and viscous liquids by laser-induced breakdown spectroscopy.

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31

Melkonyan, D. V., V. N. Velikova y A. L. Berezovska. "CHARACTERISTICS OF TRACE METALS SPATIAL DISTRIBUTION IN SEA BED SEDIMENTS OF THE NORTH-WESTERN BLACK SEA SHELF". Odesa National University Herald. Geography and Geology 19, n.º 3(22) (3 de abril de 2015): 223–35. http://dx.doi.org/10.18524/2303-9914.2014.3(22).40420.

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The present work describes the characteristics of trace metals (TM) content and TM spatial distribution on the north-western Black Sea (NWBS) bottom as identified in the area of investigation (Ukrainian coastal waters); the sources of trace metals and their path-ways into the bottom sediments of the NWBS shelf were studied as well; the level of impact of the different land-based and marine-based sources on the content and distribution of trace metals in the sea-bed sediments of the shelf are described; the spatial distribution of trace metals of natural and anthropogenic origin in the sea-bed sediments of the shelf is presented.To quantitatively determine the impact of different sources (natural and anthropogenic) on the content and distribution of trace metals on the NWBS shelf bottom, specific statistical analysis of data was carried out. In particular, with the help of cumulative probability curve, the content of trace metals was separated into groups coming from different sources: natural sources – А; technogenic diffuse sources – В, technogenic point sources – С). The method proposed allows separating the share of input of the various sources forming the content and distribution of trace metals in the marine environment, as demonstrated on the example of bottom sediments in the present investigation.

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32

Majolagbe, A. O., S. O. Anko, K. A. Yusuf y A. A. Ayodele. "Evaluation of potentially toxic metals load and risk assessment in sediments from coastal areas of Lagos State". Global Journal of Earth and Environmental Science 8, n.º 2 (30 de abril de 2023): 14–23. http://dx.doi.org/10.31248/gjees2023.133.

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Trace metal pollution is of global concern due to its adverse effects on human health. Sediments in water bodies are a repository of pollutants, including trace metals, and since they are non-biodegradable, they have negative impact on the ecosystems. Trace metals are due to both anthropogenic and natural sources. Sediments are monitors of trace metal pollution. The study, therefore, aims at assessing the trace heavy metals (THM) in the surface sediments of coastal areas in Lagos State. Forty (40) sediments samples (top and sub-sediment soil) were collected from five coastal communities: Langbasa, Itumaro, Ibeshe, Epe and Badagry, analyzed for pH and trace metals using Atomic Absorption Spectrometry (AAS). Ecological tools: pollution classification, pollution index, and geo accumulation index were further used along with application of sediments quality guidelines to reveal trends and variations in sediment investigated. The pH values range from 4.7- 6.4, while the trace metals concentration ranges from 1.6 - 6.42, 36.2 - 104.5, 0.05 - 63.6, 0.00 - 0.17, 32.1 - 266.3, 3.7 - 5.94, 0.00 - 0.00 mg/kg for Zn, Fe, Cu, Pb, Ca, Mg and Ni respectively. The order of concentration of the metals was Ca > Fe > mg > Cu > Zn > Pb. The monomial and overall ecological potential risks for the trace potentially toxic metals investigated (lead, iron, zinc and copper) in the study area posed low potential risk (<40) and (< 110) respectively. The order of deteriorations (potential risk) in the study area is Badagry > Ibeshe > Epe > Itumaro > Langbasa. Continuous monitoring of trace heavy metals is important to ensure health safety and sustainable environment.

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33

Edmonds, Marie, Emily Mason y Olivia Hogg. "Volcanic Outgassing of Volatile Trace Metals". Annual Review of Earth and Planetary Sciences 50, n.º 1 (31 de mayo de 2022): 79–98. http://dx.doi.org/10.1146/annurev-earth-070921-062047.

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Volcanoes play a key role in the cycling of volatile metals (e.g., chalcophile elements such as Tl, Pb, and Cu and metalloids such as As, Te, and Se) on our planet. Volatile metals and metalloids are outgassed by active volcanoes, forming particulate volcanic plumes that deliver them in reactive form to the environment, where they may be nutrients (e.g., Cu and Zn) or pollutants (e.g., Hg, As, Pb). Volcanic outgassing rates of these elements compare to those associated with building ore deposits in the crust and to anthropogenic emission rates. There are distinct compositional differences between volcanic plumes in different tectonic settings, related to the enrichment of arc magmas in metals transported in slab fluids, metal speciation, and partitioning between silicate melt, vapor, and magmatic sulfide. Volcanic gases have compositions similar to those of quartz-hosted fluid inclusions found in mineralized granites, albeit with a lower density and salinity. Volatile volcanic metals are transported as soluble aerosols in volcanic plumes and may persist for hundreds of kilometers in the troposphere. Volcanic metal chloride aerosols in tropospheric volcanic plumes at high latitudes are recorded in ice cores. ▪ Volcanoes emit significant fluxes of volatile trace metals such as Cu, Tl, and Pb, as gases and particulates, to the surface environment. ▪ There is a distinct metal compositional fingerprint in volcanic and hydrothermal plumes at subduction and hotspot volcanoes and mid-ocean ridges, controlled by magma and fluid chemistry. ▪ Volcanic gases are the less saline equivalent of the fluids forming economic porphyry deposits of chalcophile metals (e.g., Cu) in the crust. ▪ The metals in tropospheric volcanic plumes may be rained out near the vent, but in dry environments they may persist for thousands of kilometers and be deposited in ice cores.

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34

Dube, Siphesihle, Nkosinathi Makhubela, Lawrence Mzukisi Madikizela, Nkoana Ishmael Mongalo, Vusumzi Emmanuel Pakade, Bethusile Rejoice Maseko y Somandla Ncube. "Health Risk Assessment of Metals in African Aphrodisiacs: A Case Study of Aqueous Concoctions from Johannesburg and Durban Herbal Markets, South Africa". Applied Sciences 13, n.º 4 (7 de febrero de 2023): 2148. http://dx.doi.org/10.3390/app13042148.

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Consumption of aphrodisiacs is a common practice in South Africa. Hence, determining the levels of trace metals as potential pollutants is necessary to protect consumers’ health. The current study reports a health risk assessment due to metals in aphrodisiacs collected from herbal markets in Johannesburg and Durban, South Africa. Samples were digested using microwave-assisted digestion followed by inductively coupled plasma-optical emission spectrometry analysis. The results showed that the concentrations of common metals (Na, K, Mg, and Ca) were within the guideline limits for human consumption, while the trace metals (Ni, Cr, Co, As, Cd, and Pb) were above the limits, recording values of 0.132–0.268, 0.209–0.308, 0.224–0.405, 0.0884–0.230, 0.0402–1.11, and 0.146–0.207 mg L−1, respectively. The source of the trace metals was traced to the tap water probably collected from dilapidated buildings where the water systems are ailing. A strong correlation for metals with similar sources was observed, notably for Pb and Cd that leach from water pipes. The aphrodisiacs had low consumption rates, and the health risk assessment gave a hazard quotient of 0.225 as a total for all studied metals. The group of aphrodisiacs investigated in the current study therefore poses minimal health risks and can be consumed without fear of metal contamination. More inclusive studies are, however, needed to have a better understanding of aphrodisiacs with the aim of potentially commercializing them like the other commercialized herbal concoctions currently distributed in South African markets and pharmacies.

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35

FIRFILIONIS, G., V. PARASKEVOPOULOU, G. VILIOTI y M. DASSENAKIS. "The removal of trace metals at the wastewater treatment plant of Psyttalia". Mediterranean Marine Science 5, n.º 1 (1 de junio de 2004): 71. http://dx.doi.org/10.12681/mms.212.

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The present study investigates the levels of trace metals in the input and output of the Psyttalia wastewater treatment plant, as well as the removal of the various trace metal forms (dissolved, particulate) during primary sedimentation. The trace metals determined were: Pb, Cd, Cu, Zn, Cr, and Ni. The experimental procedure included the collection and analysis of inflow and outflow samples. Dissolved and particulate forms were separated by filtration through 0.45 and 8 Μm Millipore filters and trace metals were determined using atomic absorption spectrometry. The results indicate that particulate matter consists mainly of large particles (> 8 µ m ) and the sedimentation process is more effective in their removal in contrast to smaller particles. The removal of trace metals during primary sedimentation follows the decreasing sequence: Particulate metal in large particles > Particulate metal in small particles > Dissolved metal. Concerning the various metals the removal follows the sequence: Pb ~= Cu>Zn ~= Cr>Cd>Ni. The quantities of trace metals that are discharged to the sea through the outflow pipes of the Psyttalia treatment plant follow the decreasing sequence: Zn >> Cr > Cu > Ni > Pb > Cd.

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36

Li, Guolian, Guijian Liu, Chuncai Zhou, Yu Kang, Wanqing Yuan y Fazhi Xie. "Mobility, binding behavior and potential risks of trace metals in the sediments of the fifth largest freshwater lake, China". Water Science and Technology 67, n.º 11 (1 de junio de 2013): 2503–10. http://dx.doi.org/10.2166/wst.2013.099.

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The trace metal pollution of sediments in Chaohu Lake, one of the most highly eutrophic lakes in East China, was investigated. Surface sediment (0–5 cm) samples were collected from 35 different positions and analyzed by inductively coupled plasma optical emission spectrometry to determine trace metal contents. Results showed that the mean content of trace metals was as follows: Cr, 85.09 mg kg−1; Cu, 34.49 mg kg−1; Ni, 26.46 mg kg−1; Pb, 34.17 mg kg−1 and Zn, 107.46 mg kg−1. The trace metal concentrations from different sampling sites displayed spatial diversity; the heavily polluted sampling sites were close to where estuaries flow in to the lake. A four-step sequential extraction was used to examine the partitioning of the trace metals. Results demonstrated that the percentage of the species bound to the oxidizable phase for all trace metals ranged from 15.6 to 37.7%, while for Cu, Cr and Ni, the main forms were residual (41.3, 62.3 and 69.8%, respectively). Trace metals in the oxidizable fraction may mainly exist in the form of sulfides. The ecological potential risks of trace metals decreased as follows: Pb > Zn > Cu > Cr > Ni.

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37

Fasfous, Ismail I., C. L. Chakrabarti, John Murimboh y Tahir Yapici. "Complexation of Lead in Model Solutions of Humic Acid: Heterogeneity and Effects of Competition with Copper, Nickel, and Zinc". Environmental Chemistry 3, n.º 4 (2006): 276. http://dx.doi.org/10.1071/en06022.

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Environmental Context. Metal bioavailability and toxicity are often related to free metal concentration rather than total metal concentration. Humic substances are chemically and physically heterogeneous complexants for metals in natural waters, and play an important role in trace metal transport, fate, and bioavailability. Metal bioavailability, which depends on chemical speciation of metals, is greatly influenced by the presence of other trace metals and major cations in natural waters. In this work, the effects of heterogeneity of humic substances, and of competition of trace metals on lead speciation in model solutions have been studied to gain a better understanding of these effects on complexation of trace metal lead and its bioavailability. Abstract. Physicochemical heterogeneity of a well characterized humic acid (HA) in its complexation with a trace metal lead in model solutions was investigated using pseudo-polarography at a stationary mercury drop electrode, and the differential equilibrium function (DEF) of Pb(ii)–HA complexes was determined. The complexation of Pb(ii) by HA was determined by taking into account the dependence of the strength of the binding on the metal (Pb) loading. Also investigated were the effects of competition of the trace metals copper, nickel, and zinc on the DEF of Pb(ii)–HA complexes in model solutions. The results showed that these trace metals competed with trace metal lead for binding by HA even when present at the same concentrations as that of lead.

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38

Negra, Christine, Donald S. Ross y Antonio Lanzirotti. "Soil Manganese Oxides and Trace Metals". Soil Science Society of America Journal 69, n.º 2 (marzo de 2005): 353–61. http://dx.doi.org/10.2136/sssaj2005.0353.

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39

TAKEDA, Atsushi. "Essential Trace Metals and Brain Function". YAKUGAKU ZASSHI 124, n.º 9 (1 de septiembre de 2004): 577–85. http://dx.doi.org/10.1248/yakushi.124.577.

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40

Berman, Shier S., Philip A. Yeats y Klaus Kremling. "Sampling of Seawater for Trace Metals". Critical Reviews in Analytical Chemistry 16, n.º 1 (1985): 1–14. http://dx.doi.org/10.1080/10408348508085457.

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41

Berman, Shier S., Philip A. Yeats y Klaus Kremling. "Sample of Seawater for Trace Metals". C R C Critical Reviews in Analytical Chemistry 16, n.º 1 (enero de 1985): 1–14. http://dx.doi.org/10.1080/10408348508542783.

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42

Ragnarsdottir, K. V. "Ejection of Trace Metals from Volcanoes". Mineralogical Magazine 58A, n.º 2 (1994): 752–53. http://dx.doi.org/10.1180/minmag.1994.58a.2.128.

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43

Ross, Howard B. "Trace metals in precipitation in Sweden". Water, Air, and Soil Pollution 36, n.º 3-4 (1987): 349–63. http://dx.doi.org/10.1007/bf00229677.

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44

Lin, T. S. y F. M. Shen. "Trace Metals in Mosquito Coil Smoke". Bulletin of Environmental Contamination and Toxicology 74, n.º 1 (enero de 2005): 184–89. http://dx.doi.org/10.1007/s00128-004-0566-y.

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45

Wong, Coby S. C., Xiangdong Li y Iain Thornton. "Urban environmental geochemistry of trace metals". Environmental Pollution 142, n.º 1 (julio de 2006): 1–16. http://dx.doi.org/10.1016/j.envpol.2005.09.004.

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46

Timmermans, Klaas R. "Ecotoxicity of trace metals for chironomids". Netherlands Journal of Aquatic Ecology 26, n.º 2-4 (junio de 1992): 559–61. http://dx.doi.org/10.1007/bf02255290.

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47

Marongiu, F., S. Marongiu, M. F. Ruberto, G. Faa y D. Barcellona. "Trace metals and the hemostatic system". Clinica Chimica Acta 547 (julio de 2023): 117458. http://dx.doi.org/10.1016/j.cca.2023.117458.

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48

Tan, Siyi, Hairong Zhao, Wanqin Yang, Bo Tan, Kai Yue, Yu Zhang, Fuzhong Wu y Xiangyin Ni. "Forest Canopy Can Efficiently Filter Trace Metals in Deposited Precipitation in a Subalpine Spruce Plantation". Forests 10, n.º 4 (7 de abril de 2019): 318. http://dx.doi.org/10.3390/f10040318.

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Trace metals can enter natural regions with low human disturbance through atmospheric circulation; however, little information is available regarding the filtering efficiency of trace metals by forest canopies. In this study, a representative subalpine spruce plantation was selected to investigate the net throughfall fluxes of eight trace metals (Fe, Mn, Cu, Zn, Al, Pb, Cd and Cr) under a closed canopy and gap-edge canopy from August 2015 to July 2016. Over the one-year observation, the annual fluxes of Al, Zn, Fe, Mn, Cu, Cd, Cr and Pb in the deposited precipitation were 7.29 kg·ha−1, 2.30 kg·ha−1, 7.02 kg·ha−1, 0.16 kg·ha−1, 0.19 kg·ha−1, 0.06 kg·ha−1, 0.56 kg·ha−1 and 0.24 kg·ha−1, respectively. The annual net throughfall fluxes of these trace metals were −1.73 kg·ha−1, −0.90 kg·ha−1, −1.68 kg·ha−1, 0.03 kg·ha−1, −0.03 kg·ha−1, −0.02 kg·ha−1, −0.09 kg·ha−1 and −0.08 kg·ha−1, respectively, under the gap-edge canopy and 1.59 kg·ha−1, −1.13 kg·ha−1, −1.65 kg·ha−1, 0.10 kg·ha−1, −0.04 kg·ha−1, −0.03 kg·ha−1, −0.26 kg·ha−1 and −0.15 kg·ha−1, respectively, under the closed canopy. The closed canopy displayed a greater filtering effect of the trace metals from precipitation than the gap-edge canopy in this subalpine forest. In the rainy season, the net filtering ratio of trace metals ranged from −66.01% to 89.05% for the closed canopy and from −52.32% to 33.09% for the gap-edge canopy. In contrast, the net filtering ratio of all trace metals exceeded 50.00% for the closed canopy in the snowy season. The results suggest that most of the trace metals moving through the forest canopy are filtered by canopy in the subalpine forest.

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49

Millo, Christian, Carlo Bravo, Stefano Covelli, Elena Pavoni, Elisa Petranich, Marco Contin, Maria De Nobili et al. "Metal Binding and Sources of Humic Substances in Recent Sediments from the Cananéia-Iguape Estuarine-Lagoon Complex (South-Eastern Brazil)". Applied Sciences 11, n.º 18 (12 de septiembre de 2021): 8466. http://dx.doi.org/10.3390/app11188466.

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The Cananéia-Iguape estuarine–lagoon complex (São Paulo state, Brazil) is a natural laboratory to study metal binding by humic substances (HS) in subtropical settings. This transitional environment is evolving into a freshwater environment due to water input from the Ribeira River, funneled through the Valo Grande Canal (Iguape). Past mining activities in the Ribeira River basin and maritime traffic are suspected to be potential sources of trace metals in the system. In this study, the trace metal contents of Free Humic Acids (FHA), Bound Humic Acids (BHA), and Fulvic Acids (FA) extracted from sedimentary organic matter were investigated. Moreover, the sources of HS were traced using their stable carbon isotope compositions and C/N ratios. The results suggested a mixed marine–terrestrial source of FHA, BHA, and FA. Copper and Cr were the most abundant trace metals bound to HS. On average, Cu showed concentrations of 176, 115, and 37.9 μg g−1 in FHA, BHA, and FA, respectively, whereas Cr showed average concentrations of 47.4, 86.3, and 43.9 μg g−1 in FHA, BHA, and FA, respectively. Marine FHA showed the highest binding capacity for trace metals, whereas terrestrial FA derived from the decay of mangrove organic matter showed the lowest binding capacity.

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50

Mestek, Oto, Jana Komínková, Jiří Šantrůček, Petr Kačer, Kateřina Mališová y Richard Koplík. "Analyses of trace metals, peptide ligands of trace metals and mercury speciation in home prepared bread". Chemical Speciation & Bioavailability 24, n.º 2 (enero de 2012): 79–88. http://dx.doi.org/10.3184/095422912x13325261626531.

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