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Environmental pollutants may often alter the genetic components of natural populations. In this study, heavy metals and genetic diversity in land snail (Achatina achatina) from three populations of south-western Nigeria were investigated, using the Atomic Absorption Spectrometry and DNA Sequencing technology respectively. Metal analysis revealed that the snails accumulated lead (Pb) and nickel (Ni) in high concentrations in two of the three states, while cadmium (Cd) was the least detected. Editing and alignment of the sequences of all snail accessions generated a range of 384bp to 419 bp. Analysis of Molecular Variance (AMOVA) in all 18 accessions was low at only 16%. The query coverage (QC) ranged between 96% and 100%, with 14 (77.8%) of the 18 accessions showing 100% identity. Pairwise comparison of the accessions studied also showed a high genetic similarity. The unweighted pair group method with arithmetic mean (UPGMA) generated two main clusters. Cluster I was unique and contain one sample (AaOy06) while the other cluster are very closely related and can be further sub-divided into sub-clusters. The similarity index of between the clusters is 0.5357. The close similarity among the accessions may be due to the geographical proximity of the three states. The uniqueness of accession AaOy06 in comparison to other accessions might be due to the negative influence of heavy metal, particularly lead. The determination of evolutionary relationships among snail populations may be useful towards the breeding efforts of the species in Nigeria.
Os poluentes ambientais podem frequentemente alterar os componentes genéticos das populações naturais. Neste estudo, metais pesados e diversidade genética em caramujos terrestres (Achatina achatina) de três populações do sudoeste da Nigéria foram investigados, usando a tecnologia de espectrometria de absorção atômica e sequenciamento de DNA, respectivamente. A análise dos metais revelou que os caramujos acumularam chumbo (Pb) e níquel (Ni) em altas concentrações em dois dos três estados, enquanto o cádmio (Cd) foi o menos detectado. A edição e o alinhamento das sequências de todos os acessos de caramujos geraram uma faixa de 384pb a 419pb. A análise de variância molecular (AMOVA) em todos os 18 acessos foi baixa em apenas 16%. A cobertura da consulta (QC) variou entre 96% e 100%, com 14 (77,8%) dos 18 acessos apresentando 100% de identidade. A comparação pareada dos acessos estudados também mostrou alta similaridade genética. O método de grupo de pares não ponderados com média aritmética (UPGMA) gerou dois clusters principais. O cluster I era único e contém uma amostra (AaOy06), enquanto o outro cluster está intimamente relacionado e pode ser subdividido em subclusters. O índice de similaridade entre os clusters é 0,5357. A grande semelhança entre os acessos pode ser devido à proximidade geográfica dos três estados. A singularidade do acesso AaOy06 em comparação com outros acessos pode ser devido à influência negativa de metais pesados, particularmente chumbo. A determinação das relações evolutivas entre as populações de caramujos pode ser útil para os esforços de reprodução da espécie na Nigéria.
Subject(s)
Animals , Snails , Genetic Variation , Metals, Heavy , Environmental PollutantsABSTRACT
Aims: To assess the source and level of Nickel in selected surface waters and its impact on the community of the Bonaberi industrial zone. Study Design: Cross-sectional study design that involved semi-quantitative and qualitative data collection method. Place and Duration of Study: This study was carried out in the area of Bonaberi industrial zone, Douala IV district between February 2019 to August 2020. Methodology: 25 Different surface water samples were collected from 5 sampling sites. Water samples were collected in polyethylene bottles previously washed with deionized water and rinsed with sample to be collected from different sites and acidified with 5 ml concentrated nitric acid. The contents of the metal were analyzed using Colorimetric merck microquant procedure. Two way ANOVA test and a P-value (<0.05) was considered significant. Results: Spring Water had a significant concentration of nickel in the various sites (0.06 mg/L), industrial waste (0.05 mg/L), River (0.04 mg/L), Well (0.03 mg/L), Tap waters (0.02 mg/L). Conclusion: Nickel is one of the most toxic naturally occurring metal(s) that is very dangerous to environmental sustainability when present in high concentrations. The study justifies the need to ascertain the long-term effects of Nickel contaminant(s) at waste dumping sites. Strengthening waste management systems and water quality monitoring should be implemented in the watersheds to minimize the health effects and deterioration of the aquatic ecosystem. Adequate measures should be taken to educate the community on heavy metals pollution on surface water and their effects to health and environment.
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Background: Environmental exposure to toxins has been strongly implicated in its multi-faceted etiology of chronic kidney disease, a serious public health problem affecting individuals, families, and communities. There is a need to synthesize available studies on the effect of heavy metal exposure on renal function, considering the rising global burden of kidney disease. The objective of this study is to determine the association between exposure to heavy metals and renal disease. Methods: The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) were used to conduct the review. A comprehensive independent search, title, abstract, and full-text screening of available literature on Google Scholar, PubMed, and OAREScience was done between March 2021 and May 2021. The criteria for study inclusion were full-text articles published in English language in the last 20 years (2001-2020), and observational primary human studies reporting the association between heavy metal exposure and renal disease. The Newcastle-Ottawa Quality Assessment Scale was used to assess the quality of the included studies. Results: A total of 552 studies were identified following the search from the different databases. A total of 13 studies were finally included in the review. Heavy metals implicated in the studies include cadmium, lead, mercury, and arsenic, with ten studies showing environmental exposure as the primary source. Ten (10) studies showed an association between heavy metal exposure and renal impairment (p<0.05) while only 3 studies reported no association. Conclusion: Environmental monitoring is needed to stem the tide of heavy metal exposure in view of the growing burden of chronic kidney disease.
Subject(s)
Humans , Male , Female , Metals, Heavy , Environmental Exposure , Renal Insufficiency, Chronic , Systematic ReviewABSTRACT
Abstract Since water is one of the essentials for life, the presence and quality of water in the habitat is extremely important. Therefore, water quality change and management of Lake Aygır was investigated in this study. For this, water samples collected from the lake and the irrigation pool between May 2015 and May 2016 were analyzed monthly. Spectrophotometric, titrimetric and microbiological methods were used to determine the water quality. According to some water quality regulations, HCO3, NH4, Cu, Mo, Br, fecal coliform and total suspended solid (TSS) values were found above the limit values. The other 29 parameters comply with Turkish national and international legislations. Lake Aygır was negatively affected by the surrounding settlements and agricultural activities. It is thought that the water resource should be monitored periodically and remedial studies should be done to prevent parameters exceeding the limits. However, Lake Aygır was generally suitable for drinking, use, fishing and irrigation.
Resumo Como a água é um dos elementos essenciais para a vida, a presença e a qualidade da água no habitat são extremamente importantes. Portanto, a mudança da qualidade da água e a gestão do lago Aygır foram investigadas neste estudo. Para isso, amostras de água coletadas no lago e na piscina de irrigação entre maio de 2015 e maio de 2016 foram analisadas mensalmente. Métodos espectrofotométricos, titulométricos e microbiológicos foram usados para determinar a qualidade da água. De acordo com alguns regulamentos de qualidade da água, os valores de HCO3, NH4, Cu, Mo, Br, coliformes fecais e total sólido suspenso (TSS) foram encontrados acima dos valores limite. Os outros 29 parâmetros estão em conformidade com as legislações nacionais e internacionais turcas. O lago Aygır foi afetado negativamente pelos assentamentos e atividades agrícolas ao redor. Pensa-se que o recurso hídrico deve ser monitorado periodicamente e estudos corretivos devem ser feitos para evitar que os parâmetros ultrapassem os limites. No entanto, o lago Aygır era geralmente adequado para beber, usar, pescar e irrigar.
Subject(s)
Water Pollutants, Chemical/analysis , Lakes , Turkey , Water Quality , Environmental Monitoring , FisheriesABSTRACT
Epigallocatechin gallate (EGCG) is a major polyphenol component in green tea. EGCG has high free radical scavenging activity, radiation protection efficiency, and metal-chelating capacity due to its unique structure with hydroxyl groups. EGCG and its derivatives have been reported in various fields. This paper reviews the effects of EGCG, including radiation protection, heavy metal ion adsorption, and promotion of heavy metal ion excretion. EGCG has the potential to be used as an ideal radiation protection agent, heavy metal adsorbent, and even excretion promoting agent.
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Inductively coupled plasma mass spectrometry (ICP-MS) was applied to determine the concentrations of lead (Pb), cadmium (Cd) and arsenic (As) in Lindera aggregata (Sims) Kosterm. The physiologically based extraction test (PBET) digestion in vitro/Caco-2 cell model was established to investigate the bioaccessible contents of Pb, Cd and As in decoction of Lindera aggregata (Sims) Kosterm. The target-organ toxicity dose modification of HI method (TTD) was used to evaluate the cumulative risk caused by the combined exposure of the total levels of Pb, Cd and As in Lindera aggregata (Sims) Kosterm. and the bioaccessible contents in the decoction. The results showed that the total contents of Pb, Cd and As in 4 batches of samples were in the range of 2.901-3.872, 1.299-1.800 and 0.062-0.216 mg·kg-1, respectively. After transportation by Cacco-2 cells, the bioaccessible contents of Pb, Cd, and As in the decoction were in the range of 0.045-0.080, 0.070-0.112 and 0.004-0.018 mg·kg-1. The results of risk assessment showed that calculated by the total amounts of heavy metals in the Lindera aggregata (Sims) Kosterm., for the end points of nervous system, the cumulative risks of co-exposure of heavy metals in 3 batches of samples were of concern. After decoction and transportation by Caco-2 cells, for the end points of cardiovascular system, blood, nervous system, kidney and testis, the TTD modification of HI values of all batches of samples were less than 1, and the health risks were acceptable. The study provided methodology basis for a more objective assessment of the health risks of heavy metals and harmful elements in traditional Chinese medicine and for a more scientific limit standard of heavy metals and harmful elements.
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There is a bidirectional interactive relationship between heavy metals and intestinal microorganisms. Single exposure to common heavy metals (Cd, Cr, As, Pb, etc.) may cause intestinal microecological damage and related diseases by losing the diversity and relative abundance of intestinal microorganisms. However, heavy metals in the environment are usually mixed exposure and an overall toxic effect is presented. Published studies have suggested a synergistic effect between most heavy metals, so the impact of mixed exposure on intestinal microorganisms is expected to be more significant than that of single exposure. Intestinal microorganisms are the first line of defense against heavy metals entering the body, and can reduce inflammation and oxidation caused by heavy metals via changing protein synthesis, intestinal PH, enzyme activity, etc. At the same time, the colonization of oral probiotics in the intestinal tract has a significant detoxification effect on heavy metals entering the body through synergy with intestinal microorganisms, which can promote the elimination of heavy metals, reduce the production of oxides and inflammatory mediators, reverse the changes in the relative abundance of intestinal microorganisms, and then reduce the damage of heavy metals to intestinal microecology. Therefore, probiotics may have better prospects than traditional heavy metal antidotes. In the future, more in-depth research on the mechanism of bidirectional interactive relationship between heavy metals and intestinal microorganisms is needed to provide new ideas for clinical heavy metal detoxification.
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Heavy metal pollution poses a serious threat to the environment and human health. Guizhou is a province with apparent regional features of heavy metal pollution such as lead, zinc, mercury, and arsenic in agriculture and mining soils. The coefficient of variation results showed that heavy metal pollution in the soils of agricultural planting areas and mine caves was closely related to human activities, and arsenic and zinc were greatly affected by human activities. In the water environment, mercury pollution presents in mine cave water samples, and cadmium, mercury, and lead pollution present in scenic park water samples. The results of single-factor pollution index showed that mercury in mine cave water samples and cadmium, mercury, and lead in scenic park water samples were graded as severe pollution. The results of Nemero pollution index showed the highest comprehensive pollution level of heavy metals was in scenic park water samples. In atmospheric dust fall, cadmium, mercury, lead are the most prominent pollution. Potential risks to ecological environment were identified for cadmium and mercury in all study areas and lead in other areas outside Wanshan. The results of integrated potential ecological risk index indicated a high-risk level of heavy metal pollution in atmospheric dust fall in the current study area. At present, the heavy metal pollutants in the environment of Guizhou are mainly originated from natural factors such as geological background content and soil-forming parent material, and human activities such as mining, metal smelting, agricultural activities, and sewage irrigation. The analysis showed serious heavy metal pollution in the environment of Guizhou, which caused harm to the local environment. It is crucial that environmental protection measures be taken during human activities.
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Background The human body is usually exposed to a variety of heavy metals at the same time, and different types and concentrations of heavy metals may have complex interactions during their absorption and metabolism in the human body. Seminal fructose is an important energy source for sperm movement. A large number of studies have shown that metal exposure may impair semen quality, and seminal fructose is an important factor affecting male reproduction, so it is necessary to investigate the relationship between mixed heavy metal exposure and seminal fructose to explore the mechanism of semen quality damage caused by metal exposure. Objective To understand the status of common heavy metal exposure in men of childbearing age in Puyang City, Henan Province, and to study the relationship between mixed exposure to heavy metals and seminal fructose, as well as potential interactions among heavy metals. Methods Volunteers were recruited from the Puyang Maternal and Child Health Hospital Reproductive Center for a cross-sectional survey on general demographic characteristics, smoking, alcohol consumption, and other information. Semen samples were collected to detect 12 metals such as vanadium (V), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), selenium (Se), silver (Ag), cadmium (Cd), barium (Ba), thallium (Tl), iron (Fe), and lead (Pb) in seminal plasma and seminal fructose. After correcting for selected confounding factors, a Bayesian kernel machine regression (BKMR) model was used to evaluate the impact of seminal plasma heavy metal mixed exposure and its interactions on seminal fructose. Results A total of 825 adult males were enrolled. The concentrations in M (P25, P75) of V, Mn, Co, Ni, Zn, Se, Ag, Cd, Ba, Tl, Fe, and Pb in seminal plasma were 0.39 (0.28, 0.54), 12.31 (8.92, 17.52), 0.26 (0.18, 0.38), 5.15 (3.32, 8.64), 182159.80 (121847.80, 199144.50), 13.61 (10.55, 17.68), 0.03 (0.02, 0.04), 0.34 (0.27, 0.46), 8.64 (5.94, 13.43), 0.06 (0.05, 0.08), 168.74 (114.17, 259.45), and 1.69 (1.15, 2.36) μg·L−1 respectively. The Spearman correlation results indicated that there was a negative correlation between V, Mn, Co, Zn, Se, Ba, Tl, or Fe in seminal plasma and seminal fructose (P<0.05), and the values of r (95%CI) were −0.044 (−0.087, −0.001), −0.129 (−0.171, −0.087), −0.055 (−0.099, −0.012), −0.099 (−0.143, −0.056), −0.053 (−0.097, −0.010), −0.068 (−0.111, −0.025), −0.095 (−0.138, −0.052), and −0.082 (−0.125, −0.039), respectively. The results of multiple linear regression indicated that there was a negative correlation between the exposure level of Cd, Mn, Zn, Ag, Ba, Tl, or Fe in seminal plasma and seminal fructose (P<0.05), the values of associated β (95%CI) were −0.551 (−0.956, −0.147), −0.315 (−0.419, −0.212), −0.187 (−0.272, −0.103), −0.161 (−0.301, −0.021), −0.188 (−0.314, −0.062), −1.159 (−2.170, −0.147), and −0.153 (−0.230, −0.076), respectively. The BKMR model analysis showed that seminal fructose level decreased with the increase of plasma metal mixed exposure concentration. Compared with all metal exposure at P50, the seminal fructose level decreased by 0.2374 units when all metal exposure was at P75. Seminal plasma Zn [posterior inclusion probabilities (PIPs)=1.0000] had the strongest effect on seminal fructose, followed by Mn (PIPs=0.5872), Se (PIPs=0.5656), and Ba (PIPs=0.5398). The univariate exposure-response curve showed a negative approximate linear correlations between Ba or Mn and seminal fructose, a positive linear correlation between Se and seminal fructose, and an approximate inverted U-shaped association between Zn and seminal fructose. No significant interaction between studied metals was found. Conclusion Mixed metal exposure may lead to decrease of seminal fructose, in which Zn, Mn, Se, and Ba may play an important role. Mn and Zn exposure may reduce the level of seminal fructose, Se may increase the level of seminal fructose, and there may be a threshold effect between Zn exposure and seminal fructose level. No interaction between different metals on seminal fructose is found.
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Since water is one of the essentials for life, the presence and quality of water in the habitat is extremely important. Therefore, water quality change and management of Lake Aygır was investigated in this study. For this, water samples collected from the lake and the irrigation pool between May 2015 and May 2016 were analyzed monthly. Spectrophotometric, titrimetric and microbiological methods were used to determine the water quality. According to some water quality regulations, HCO3, NH4, Cu, Mo, Br, fecal coliform and total suspended solid (TSS) values were found above the limit values. The other 29 parameters comply with Turkish national and international legislations. Lake Aygır was negatively affected by the surrounding settlements and agricultural activities. It is thought that the water resource should be monitored periodically and remedial studies should be done to prevent parameters exceeding the limits. However, Lake Aygır was generally suitable for drinking, use, fishing and irrigation.
Como a água é um dos elementos essenciais para a vida, a presença e a qualidade da água no habitat são extremamente importantes. Portanto, a mudança da qualidade da água e a gestão do lago Aygır foram investigadas neste estudo. Para isso, amostras de água coletadas no lago e na piscina de irrigação entre maio de 2015 e maio de 2016 foram analisadas mensalmente. Métodos espectrofotométricos, titulométricos e microbiológicos foram usados para determinar a qualidade da água. De acordo com alguns regulamentos de qualidade da água, os valores de HCO3, NH4, Cu, Mo, Br, coliformes fecais e total sólido suspenso (TSS) foram encontrados acima dos valores limite. Os outros 29 parâmetros estão em conformidade com as legislações nacionais e internacionais turcas. O lago Aygır foi afetado negativamente pelos assentamentos e atividades agrícolas ao redor. Pensa-se que o recurso hídrico deve ser monitorado periodicamente e estudos corretivos devem ser feitos para evitar que os parâmetros ultrapassem os limites. No entanto, o lago Aygır era geralmente adequado para beber, usar, pescar e irrigar.
Subject(s)
Human Settlements/policies , Water Microbiological Characteristics/analysis , Water Chemical Characteristics/analysis , Water Quality Control , Water QualityABSTRACT
Abstract Since water is one of the essentials for life, the presence and quality of water in the habitat is extremely important. Therefore, water quality change and management of Lake Aygr was investigated in this study. For this, water samples collected from the lake and the irrigation pool between May 2015 and May 2016 were analyzed monthly. Spectrophotometric, titrimetric and microbiological methods were used to determine the water quality. According to some water quality regulations, HCO3, NH4, Cu, Mo, Br, fecal coliform and total suspended solid (TSS) values were found above the limit values. The other 29 parameters comply with Turkish national and international legislations. Lake Aygr was negatively affected by the surrounding settlements and agricultural activities. It is thought that the water resource should be monitored periodically and remedial studies should be done to prevent parameters exceeding the limits. However, Lake Aygr was generally suitable for drinking, use, fishing and irrigation.
Resumo Como a água é um dos elementos essenciais para a vida, a presença e a qualidade da água no habitat são extremamente importantes. Portanto, a mudança da qualidade da água e a gestão do lago Aygr foram investigadas neste estudo. Para isso, amostras de água coletadas no lago e na piscina de irrigação entre maio de 2015 e maio de 2016 foram analisadas mensalmente. Métodos espectrofotométricos, titulométricos e microbiológicos foram usados para determinar a qualidade da água. De acordo com alguns regulamentos de qualidade da água, os valores de HCO3, NH4, Cu, Mo, Br, coliformes fecais e total sólido suspenso (TSS) foram encontrados acima dos valores limite. Os outros 29 parâmetros estão em conformidade com as legislações nacionais e internacionais turcas. O lago Aygr foi afetado negativamente pelos assentamentos e atividades agrícolas ao redor. Pensa-se que o recurso hídrico deve ser monitorado periodicamente e estudos corretivos devem ser feitos para evitar que os parâmetros ultrapassem os limites. No entanto, o lago Aygr era geralmente adequado para beber, usar, pescar e irrigar.
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@#Health impact assessment is a means of evidence-based policy-making for improvement in health. It is a combination of methods whose aim is to assess the health consequences to a population of a policy, project, or program that does not necessarily have health as its primary objective. It is described as being “the leading global network on best practice in the use of impact assessment for informed decision-making regarding policies, programs, plans and projects”. In recent years, much evidence was revealed that the mining, metal mining, and processing industry has a greatly impact on humans. Residing population has affected directly and indirectly influenced to the health and wellbeing of human. </br>The mining, metal mining and processing industries play an important role in the economic and social development of Mongolia. With the rapid development of the mining industry in Mongolia, environmental protection and environmental rehabilitation have become a priority. Currently, there are 27 laws governing environmental legal acts in our country, and chapter 3 of the Hygiene Law covers environmental and health impact assessment. As stated the implementation of the law shall be financed from the state and local budgets, the central state administrative organization and the Governor at the appropriate level shall order the relevant professional organizations to carry out environmental research and analysis work and to develop projects, and in addition to financing with budget funds, as well as conducting research with their funds for interested citizens, enterprises, and organizations were are arrangements to support the implementation of the laws and its regulation. </br>However, Within the scope of the Law on Environmental Protection and Detailed Environmental Impact Assessment Procedures, the negative impact on the environment is identified but in the area of health impact, it is a lack of information on how the activities are conducted, and health impact assessments are not conducted according to procedures and methods. Thus, there are need to conduct health impact assessments of the mining area and its affected population.
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Objective: To investigate the effect of combined exposure to four heavy metals (lead, cadmium, arsenic, mercury) on early kidney injury in occupational population. Methods: A total of 384 workers exposed to combined heavy metals in a non-ferrous metal smelting plant in Guangdong Province were selected as the research subjects using judgment sampling method. The levels of blood lead, urinary cadmium and urinary arsenic were detacted by inductively coupled plasma mass spectrometry, while urinary mercury levels were measured using cold atomic absorption spectroscopy (acidic tin chloride reduction method). The levels of biomarkers such as urinary β2-microglobulin (β2-MG), kidney injury molecule-1 (Kim-1) and neutrophil gelatinase-associated lipocalin (NGAL) were detected by enzyme-linked immunosorbent assay. Spearman correlation analysis, linear regression, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were used to analyze the association between the exposure to the four heavy metals and early kidney injury biomarkers. Results: The median of blood lead, urinary cadmium, urinary arsenic and urinary mercury were 0.47 μmol/L and 4.450, 27.790 and 0.520 μg/gCr, respectively. The median of urinary β2-MG, Kim-1 and NGAL were 62.960, 1.130 and 18.150 μg/gCr, respectively. Spearman correlation analysis showed that urinary levels of β2-MG, Kim-1, and NGAL were weakly correlated with blood lead and urinary mercury levels (all P<0.01), but not correlated with urinary cadmium and urinary arsenic (all P>0.05). The results of multiple linear regression analysis showed that urinary mercury was positively correlated with urinary β2-MG, Kim-1 and NGAL (all P<0.01), urinary arsenic was positively correlated with urinary β2-MG level (P<0.01), and blood lead was negatively correlated with urinary β2-MG and Kim-1 (all P<0.05). The WQS regression analysis showed that the combined effect of the four heavy metals was positively correlated with urinary β2-MG, Kim-1 and NGAL (all P<0.01), with mercury having the highest impact and lead the lowest. BKMR model analysis showed the increasing trend in urinary β2-MG, Kim-1 and NGAL with the increasing levels of the combined exposure to the four heavy metals. Urinary β2-MG, Kim-1 and NGAL decreased when urinary mercury level increased from the 25th percentile to the 75th percentile and the other metals were correspondingly fixed at a certain level. When the blood exposure levels of other metals remained at the corresponding median levels, urinary β2-MG, Kim-1 and NGAL levels were positively correlated with urinary arsenic level, but no significant linear dose-response relationship was observed with the other three heavy metals. Conclusion: sLead, arsenic, and mercury are independently associated with early kidney injury biomarkers in occupational population from non-ferrous metal smelting. The four heavy metals had positive combined effects on urinary β2-MG, Kim-1 and NGAL, with mercury having the greatest impact.
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Background Exposure to heavy metals has potential adverse impacts on human health, and the concentration of heavy metals in abandoned mining areas may still be higher than that in general areas, so the health risk assessment in such areas cannot be ignored. Objective To explore the health risk of heavy metal exposure and the spatial distribution characteristics of associated main metals in a typical abandoned mining area. Methods Environmental samples of irrigated soil, rice, and drinking water were collected from 13 natural villages under the jurisdiction of a township in Liuzhou, Guangxi from November to December 2019, where a typical abandoned mining was located. Finally, 13 irrigation soil samples, 11 rice samples, and 13 drinking water samples were collected. The concentrations of six metals and metalloid elements in each environmental sample were detected by inductively coupled-plasma mass spectrometry (ICP-MS), including cadmium (Cd), arsenic (As), lead (Pb), chromium (Cr), copper (Cu), and zinc (Zn). At the same time, 251 local residents were recruited for health risk assessment. Model parameters such as body weight, rice intake, and drinking water intake of local residents were obtained through field survey, and the median metal concentration of each environmental sample was taken as the risk assessment parameter of the region. The health risk of heavy metal exposure of local residents was assessed by using oral health risk assessment model of U.S. Environmental Protection Agency. The spatial distribution characteristics of health risks associated with heavy metals were evaluated by empirical Bayes interpolation method using Geographic Information System (GIS) technology. Results The positive rates of Cd, As, Pb, Cr, Cu, and Zn in the irrigated soil samples were 100.00%. The positive rate of Pb was 63.64% in the rice samples, while the rates of other metals were 100.00%. The positive rates of Cd, As, Pb, Cr, Cu, and Zn in the drinking water samples were 53.85%, 76.92%, 92.31%, 15.38%, 84.62%, and 100.00%, respectively. The results of non-carcinogenic risk assessment of oral exposure to heavy metals suggested that the contribution of heavy metals causing non-carcinogenic risk from high to low was As (70.52%) > Cd (18.03%) > Zn (6.63%) > Cu (4.12%) > Pb (0.64%) > Cr (0.06%), and the corresponding estimated non-carcinogenic risk values were 3.54 × 100, 9.05 × 10−1, 3.33 × 10−1, 2.07 × 10−1, 3.23 × 10−2, and 5.42 × 10−4, respectively. The results of carcinogenic risk assessment of oral exposure to heavy metals suggested that the contribution of studied metals from high to low was Cd (87.00%) > As (10.24%) > Cr (2.60%) > Pb (0.16%), and the estimated carcinogenic risks were 4.35× 10−3, 5.12 × 10−4, 1.30 × 10−4, and 3.08 × 10−7, respectively. Rice was the leading media associated with non-carcinogenic risk and carcinogenic risk (99.4% and 99.8% respectively). The spatial distribution characteristics of GIS showed no obvious regularity in the distribution of As in irrigated soil, rice, and drinking water. In rice and irrigated soil, the content of Cd in the villages adjacent to the mining area was obviously higher than that in the other villages, while in drinking water, the content in the villages far away from the mining area was higher. Conclusion As and Cd are the main heavy metals that increase the health risk of local residents in a typical abandoned mining area, and the distribution characteristics of the two heavy metals in different environmental media are not completely consistent.
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Phenylpropanoid metabolic pathway is one of the most important secondary metabolic pathways in plants. It directly or indirectly plays an antioxidant role in plant resistance to heavy metal stress, and can improve the absorption and stress tolerance of plants to heavy metal ions. In this paper, the core reactions and key enzymes of the phenylpropanoid metabolic pathway were summarized, and the biosynthetic processes of key metabolites such as lignin, flavonoids and proanthocyanidins and relevant mechanisms were analyzed. Based on this, the mechanisms of key products of phenylpropanoid metabolic pathway in response to heavy metal stress were discussed. The perspectives on the involvement of phenylpropanoid metabolism in plant defense against heavy metal stress provides a theoretical basis for improving the phytoremediation efficiency of heavy metal polluted environment.
Subject(s)
Plants/metabolism , Metals, Heavy/metabolism , Flavonoids/metabolism , Biodegradation, Environmental , AntioxidantsABSTRACT
Rapidly growing industrialization and increased need for transportation have led to environmental pollution, particularly heavy metals. Efficient monitoring would help planning effective strategies to curb such increasing pollution. In this context, we studied the epigenetic changes in the bryophyte Greater Fork-moss, Dicranum majus Turner so as to use to monitor the environmental stress conditions due to accumulation of heavy metals and toxic organic compounds. The hypothesis is that the DNAm (DNA methylation) signatures reflect changes in the environmental conditions, and thus could serve as an alternate monitoring tool to study environmental pollution. The vegetative form of D. majus was collected from two different geographical locations where one was near the main road (MR) and another in the forest area (FS). DNAm rate was found 10.41±2.009 and 23.37±2.94 in MR and FS, respectively (P <0.005). The only difference between the two samples were traffic related pollutants. Thus, the reuslts suggest that vehicle pollution induces epigenetic changes in bryophytes, particularly DNA methylation, and could serve as a valuable biomarker to assess pollution risk due to vehicle traffic.
ABSTRACT
Industrial waste is released into the environment and leads to various types of heavy metal, which are toxic, mutagenic and carcinogenic in nature. Heavy metals are not biodegradable but accumulated by living organisms and cause diseases at even low concentrations. In this study, we selected four anthropogenic sites from Chambal region, isolated bacteria and investigated its heavy metal removal capability. The bacteria was isolated and identified as Escherichia coli (Ag-5), on the basis of biochemical and 16S rRNA gene sequence. Among the five (cadmium, cobalt, lead, nickel and zinc) heavy metals studied, Ni2+ has been observed to be highly toxic with minimum inhibitory concentration score of 200 ppm. E. coli could tolerate Zn2+ (300 ppm), Cd2+ (400 ppm), Co2+ (400 ppm) and Pb+2 (500 ppm). Heavy metal tolerance capability was also evaluated by UV rays treated E. coli (Ag-5) isolate and compared with wild strain Ag-5. The result indicated that the tolerance capability was enhanced by UV rays treated bacterial isolate as compared to wild strain with respect to all tested heavy metals. Atomic absorption spectroscopy results revealed that wild strain removed 78.2% cadmium nitrate, while UV rays 30 and 60 s. exposed strain removed 85.9 and 83% cadmium nitrate. Wild strain removed 64.4% nickel chloride, while UV rays 30 and 60 s exposed strain removed 66.9 and 74.5% nickel chloride. The results indicate that indigenous E. coli treated with UV rays could serve as heavy metal tolerant bacteria and utilized in bioremediation processes.
ABSTRACT
Alternative forms of medicine like Ayurveda have witnessed a rise in global popularity over the recent decades. Drugs used in Ayurveda, particularly those of mineral origin can lead to toxic effects due to heavy metal overdose. Here, we report the case of a 53-year-old woman who presented with glove-and-stocking paresthesia and scaly plaques following the institution of Ayurvedic drugs containing arsenic for dermatitis. She also had a loss of distal proprioception and a hyperesthetic response to pinprick. Her blood analysis showed elevated arsenic levels; 12 times the acceptable upper limit, with normal lead, cadmium, mercury, and chromium levels. The drug was immediately stopped and there was a gradual but incomplete resolution of the paresthesia and distal weakness over the next several months. The risk of heavy metal toxicity should be briefed to the patient before the start of mineral Ayurvedic drugs. Monitoring serum levels while on these medications might help identify toxicities early and can result in the commencement of therapy at an early stage
ABSTRACT
Heavy metals such as zinc in untreated industrial effluents cause diseases and disorders in living organisms. They cannot be degraded like organic contaminants and hence have to be removed. Though physical and chemical methods are available for their removal, most of them are not economical and eco-friendly. Hence, a suitable technique is necessary to minimize the deleterious effects of dispersion of heavy metals in ecosystems. Though zinc serves as a micronutrient, it becomes toxic in higher concentrations. Bacteria can be used in the removal of zinc and the process is economical and ecofriendly. Hence, in the present study, we tested zinc removal efficiency of Bacillus subtilis (MTCC 2423) for various concentrations viz. 100, 200, 300, 400 and 500 ppm of zinc in nutrient broth for a period of 10 days. Samples were tested for the zinc level every two days in each concentration and the maximum removal was noticed after six days of treatment. With the increase in zinc concentration, both biomass and zinc removal efficiency showed an increase. Autoclaved cells showed maximum zinc removal when compared with other cell types. Among the other heavy metals tested, iron enhanced the biomass of B. subtilis during zinc treatment and the results are discussed.
ABSTRACT
Nirmal and Chakreshwar lake are two important water bodies in Vasai-Virar Taluka, are the primary source of water for the nearby villages. The objective of the study was to analysis physicochemical parameters and simultaneously monitor the heavy metal content. During the study the physicochemical parameters like pH, temperature, Total hardness, TS, TDS and TSS were evaluated in pre and post monsoon samples at three different sites from each water body. t test and two way ANOVA test were performed to assess the variation in the pre and post analysis for any significant difference. It was observed that heavy metal content was found more in pond A (Nirmal), comparative to pond B (Chakreshwar) lake.