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1.
Chemosphere ; 240: 124909, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31550590

RESUMO

Environmental pollution and human health issues due to unrestricted electronic waste (e-waste) recycling activities have been reported at a number of locations. Among different e-waste recycling techniques, open burning of e-waste releases diverse metal(loid)s into the environment, which has aroused concern worldwide. In human health risk assessments (HHRAs), oral ingestion of soil can be a major route of exposure to many immobile soil contaminants. In vitro assays are currently being developed and validated to avoid overestimation of pollutants absorbed by the human body when calculating total pollutant concentrations in HHRAs. In this study, Cu, As, Cd, Sb, and Pb bioaccessibility in polluted soils (n = 10) from e-waste open burning sites at Agbogbloshie in Accra, Ghana, was assessed using an in vitro assay, the physiologically based extraction test. A bioaccessibility-corrected HHRA was then conducted to estimate the potential health risks to local inhabitants. The in vitro results (%) varied greatly among the different metal(loid)s (Cu: 1.3-60, As: 1.3-40, Cd: 4.2-67, Sb: 0.7-85, Pb: 4.1-57), and also showed marked variance between the gastric phase and small intestinal phase. The particle sizes of soil samples and chemical forms of metal(loid)s also influenced bioaccessibility values. Using these bioaccessibility values, both the hazard index and carcinogenic risk were calculated. The hazard index was above the threshold value (>1) for 5/10 samples, indicating a potential health risk to local inhabitants.


Assuntos
Resíduo Eletrônico , Metaloides/análise , Medição de Risco , Poluentes do Solo/farmacocinética , Disponibilidade Biológica , Exposição Dietética/efeitos adversos , Exposição Dietética/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Monitoramento Ambiental , Gana , Humanos , Concentração de Íons de Hidrogênio , Metaloides/farmacocinética , Metaloides/toxicidade , Metais/análise , Metais/farmacocinética , Metais/toxicidade , Tamanho da Partícula , Reciclagem , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
2.
Sci Total Environ ; 699: 134330, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31522043

RESUMO

Rice is one of the principal staple foods, essential for safeguarding the global food and nutritional security, but due to different natural and anthropogenic sources, it also acts as one of the biggest reservoirs of potentially toxic metal(loids) like As, Hg, Se, Pb and Cd. This review summarizes mobilization, translocation and speciation mechanism of these metal(loids) in soil-plant continuum as well as available cost-effective remediation measures and future research needs to eliminate the long-term risk to human health. High concentrations of these elements not only cause toxicity problems in plants, but also in animals that consume them and gradual deposition of these elements leads to the risk of bioaccumulation. The extensive occurrence of contaminated rice grains globally poses substantial public health risk and merits immediate action. People living in hotspots of contamination are exposed to higher health risks, however, rice import/export among different countries make the problem of global concern. Accumulation of As, Hg, Se, Pb and Cd in rice grains can be reduced by reducing their bioavailability, and controlling their uptake by rice plants. The contaminated soils can be reclaimed by phytoremediation, bioremediation, chemical amendments and mechanical measures; however these methods are either too expensive and/or too slow. Integration of innovative agronomic practices like crop establishment methods and improved irrigation and nutrient management practices are important steps to help mitigate the accumulation in soil as well as plant parts. Adoption of transgenic techniques for development of rice cultivars with low accumulation in edible plant parts could be a realistic option that would permit rice cultivation in soils with high bioavailability of these metal(loid)s.


Assuntos
Exposição Dietética/estatística & dados numéricos , Monitoramento Ambiental , Metaloides/análise , Poluentes do Solo/análise , Agricultura , Arsênico/análise , Cádmio/análise , Humanos , Chumbo/análise , Mercúrio/análise , Oryza , Selênio/análise , Solo
3.
Sci Total Environ ; 700: 134382, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31698270

RESUMO

The use of contaminated biomass and waste fuels is essential for waste management, waste to energy (WtE) and mitigating carbon emissions. The contamination of heavy metals and metalloids is specially concerned by environmental regulation and waste to energy processes. In this study, comparative characterisation is performed for three typical contaminated biomass and waste fuels. i.e. recycled woods, combustible municipal solid waste, and industrial and commercial wastes. The contamination characteristics are further analysed using statistical methods (e.g. significance, correlation, profile, and principal component analyses) to identify specific contamination features, relations among the contaminants and potential contamination sources. Contamination trend is estimated based on the continuously monitoring fuel qualities, the driving forces for regulating and reduction of the contaminations, and potential changes in major contamination sources. The comparative characterisation combined with statistical analyses provides a better way to understand the contamination mechanisms. The approach can also relate the fuel contamination with the contamination sources and their changes for trend estimation. Generally, the toxic heavy metals and metalloids are expected to be significantly reduced due to stricter regulations, but there is no general trend for the reduction of other metals and metalloids because of the complicated changes in contamination sources and waste recycling streams in the near future.


Assuntos
Poluentes Ambientais/análise , Metaloides/análise , Metais Pesados/análise , Biomassa , Monitoramento Ambiental , Resíduos Sólidos/análise , Gerenciamento de Resíduos , Madeira/química
4.
Environ Monit Assess ; 191(12): 780, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31786680

RESUMO

Mangrove sediments are strong modulators of organic matter (OM) content and pollutant dynamics, acting both as sinks and sources of these components. This study aimed to assess temporal dynamics of OM within temperate mangrove sediments and their ability to sequester pollutants. Specifically, levels of trace metals (Fe, Cu, Zn, Pb, Cd) and a metalloid (As) were examined within mangrove and mudflat sediments located in a high-energy environment in Mangawhai Harbour Estuary, northern New Zealand. Sediment cores were collected from a mangrove stand and adjacent mudflats at three sediment depths during different months over a year. Variations in OM and elements were compared to rainfall and temperature patterns observed during the sampling period. All element concentrations, except for those of As, were significantly higher in mangrove compared to mudflat sediments during the entire sampling period. This is consistent with the well-reported ability of mangroves to trap suspended particles and OM. In addition, we observed a decreasing trend in trace metal concentrations with increasing sediment depth within mangrove habitat, which correlated well with decreasing OM content. Our results also suggested that most elements had different, but significant, temporal variations throughout the year, especially in mangrove sediments. Overall, the concentrations of Cu, Zn, Pb, Cd, and As in mangrove sediments increased during summer, whereas maximum levels of Fe and OM were observed in winter. This temporal pattern was determined to be related to OM and redox cycling as a result of changes in effluent input rates and physical/chemical environments during different seasons.


Assuntos
Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Metaloides , Metais Pesados , Oligoelementos , Sedimentos Geológicos/química , Metaloides/análise , Metais Pesados/análise , Nova Zelândia , Estações do Ano , Oligoelementos/análise , Poluentes Químicos da Água/análise
5.
Mar Pollut Bull ; 145: 555-563, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590823

RESUMO

The Nerbioi-Ibaizabal estuary (Bilbao, Basque Country) suffered an important input of contaminants, including metals and metalloids, between 1875 and 1975. We collected sediments in the tidal part of the river in January 2018 and measured the concentrations of 27 elements in them. At that time, two important construction works were taking place in the area: the extension of the commercial port and the opening of long semi-closed channel. Comparing the current metallic hotspots with the geographical distribution of elements in previous years (2009, 2010 and 2014) showed us that these works seem to have significantly influenced the distribution of toxic elements in the estuary, even if the critical point of the second one is still to arrive with the inundation of the connection to the mainland. Long term pollution monitoring reveals as a powerful tool to check the effects of ongoing engineering works in estuarine environments.


Assuntos
Sedimentos Geológicos/análise , Metaloides/análise , Metais/análise , Poluentes Químicos da Água/análise , Engenharia , Monitoramento Ambiental , Estuários , Limite de Detecção , Rios , Espanha
6.
Ecotoxicol Environ Saf ; 185: 109685, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31541947

RESUMO

Food security and human health can be seriously affected by heavy metal and metalloid (HM) pollution of soil. In this study, the risks posed by HMs and microbial community responses to HM pollution of agricultural soil in southwestern China were investigated. The C, N, P, and S (nutrients) concentrations were 12040.7-15912.7, 1298.06-1832.01, 750.91-2050.35, and 269.17-2115.52 mg/kg, respectively. The As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn concentrations were 3.11-8.20, 1.85-6.56, 22.83-43.96, 11.21-23.30, 0.08-0.81, 11.02-22.97, 24.07-42.96, and 193.63-698.39 mg/kg, respectively. Interpolation analysis indicated that the nutrient and HM concentrations varied spatially rather strongly. The concentrations of all of the elements were higher in soil from the northern sampling sites than in soil from the other sites. HMs in soil were found to pose high levels of risk (RI 898.85, i.e., >600). Cd contributed more than the other HMs to the risk assessment values (ErCd 293.72-1031.94), so was the most serious contaminant. Microbial diversity decreased over time in soil with high HM concentrations (plot S2) and was lower than in soil with low HM concentrations (plot S8). The nutrient and HM concentrations correlated with the microbial community characteristics. Proteobacteria, Acidobacteria, and Chloroflexi were (in decreasing order) the dominant bacterial phyla. We speculate that these phyla may be strongly resistant to HMs. The fourth most common phylum was Actinobacteria. Bacteria in this phylum could be used as biological indicators of the HM pollution status. Soil micro-ecosystems can self-regulate. HM stress will affect the evolution of soil microorganisms and relevant functional genes. The spatiotemporal variability in the microbial community responses to HMs and the spatial analysis and ecological risk assessment results will be useful reference data for the remediation of HM-polluted soil.


Assuntos
Monitoramento Ambiental/métodos , Fazendas , Metaloides/análise , Metais Pesados/análise , Microbiota/efeitos dos fármacos , Poluentes do Solo/análise , Agricultura , China , Humanos , Medição de Risco , Solo/química , Microbiologia do Solo/normas , Análise Espacial
7.
Ecotoxicol Environ Saf ; 183: 109543, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31400722

RESUMO

Aerosols from wastewater treatment plants (WWTPs) are considered to be potentially hazardous to on-site employees and surrounding residents. However, their harmful components and their effects remain poorly understood. In this study, the characteristics, responsible factors, sources and exposure risks of potential pathogens and toxic metal(loid)s in aerosols from four WWTPs were investigated. There were 21 potential pathogens and 15 toxic metal(loid)s detected in the aerosols. Arcobacter and Fe were the dominant taxa responsible for the dissimilarity of the potential pathogen population and toxic metal(loid) composition between the aerosols and the wastewater/sludge, respectively. Both meteorological factors and sources affected pathogen and toxic metal(loid) composition. The potential pathogens and toxic metal(loid)s in indoor aerosols mainly originated from wastewater/sludge, while those in outdoor aerosols originated from wastewater/sludge and ambient air. The highest respirable fraction (<3.30 µm) concentrations and proportions were detected at the aeration units. Non-carcinogenic and carcinogenic risks of toxic metal(loid)s for both adults and children were found within and/or around WWTPs, and non-carcinogenic risks of bacteria for children were found at downwind, suggesting the need for active safeguard procedures, such as that employees wear masks and work clothes, covering the main emission sites, and collecting and destroying of aerosols.


Assuntos
Microbiologia do Ar/normas , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Metaloides/análise , Metais Pesados/análise , Águas Residuárias , Adulto , Aerossóis , Arcobacter/isolamento & purificação , Arcobacter/patogenicidade , Criança , Humanos , Esgotos/microbiologia , Águas Residuárias/química , Águas Residuárias/microbiologia , Purificação da Água/métodos
8.
Environ Sci Pollut Res Int ; 26(29): 30029-30043, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31414389

RESUMO

Concentrations, health risks, and sources of 9 metal(loid)s (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn) and 16 PAHs in dusts collected from the 29 driving school campuses in the urban area of Kaifeng, Henan Province, China, were evaluated. The health risks due to exposure to these pollutants in dusts were assessed under three different scenarios (working for 10 years, 20 years, and 30 years in driving schools), using the health risk assessment model developed by US EPA. The results indicated that the mean concentrations for As, Cd, Cr, Cu, Hg, Pb, and Zn were higher than the local dust background except Co and Ni. The total PAH concentrations ranged from 198.21 to 3 400.89 µg kg-1, with a mean value of 908.72 µg kg-1. The dominant components were the two and three member-ring PAHs, accounting for 55.79% of the ∑PAHs, while PAHs with four to six member-rings accounted for 44.21% of total PAHs. The non-cancer risks of metal(loid)s in most samples were within the safe range except for two samples, with Pb as the major non-carcinogenic risk factor. The cancer risks of As, Cd, Cr, and Ni were also within the currently acceptable range except for one sample under two scenarios (working for 20a and 30a in a driving school). The cancer risks of PAHs in most samples were within the safe range except for one sample under scenario 3. The source identification results demonstrated that Pb, Zn, Cu, and Cd in the driving school dusts are mainly affected by the emission of driving-school vehicles. For PAHs, the typical driving school vehicle emissions were predominated by Phe and Ant, followed by Flu, Pyr, BkF, and Nap. The concentrations and health risks of the metal(loid)s and PAHs in the dusts were not significantly related to the driving school operation time or vehicle density, but closely related to the surrounding environments and the historical land uses of driving schools.


Assuntos
Poeira/análise , Monitoramento Ambiental/métodos , Metaloides/análise , Metais Pesados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Emissões de Veículos/análise , China , Humanos , Medição de Risco , Instituições Acadêmicas
9.
Artigo em Inglês | MEDLINE | ID: mdl-31434262

RESUMO

A total of 116 dust samples in downtown within the city wall were collected, and the spatial occurrence, source and health risk status of 19 trace metal/metalloids bound in street dusts (SDs) were systematically investigated. Geochemical maps, associations, risk models and indices were calculated to define levels of distribution, possible natural or anthropogenic sources, ecological and human health risks. It was found that the wide variations of these 19 trace metals would be observed in spatial maps, which indicated strongly anthropogenic activities inputs. Compared to the calculations of the potential ecological risk index of toxic trace metals, Pb (Eri = 20.32) ranked at the level of considerable ecological risk. The non-carcinogenic and carcinogenic risk from most trace metals exposed to children and adults were no significant health risks, except for the non-carcinogenic risk of Cr and As to children, and the carcinogenic risk of Cr to adults. The unacceptable risk locations were observed at traffic conjunctions, which should be given attention. The source apportionment results indicated that the trace metals/metalloids Co, Ga, Nb, As, Ni, and Y, coupled with main elements Al, K, Mg, Ca and Si, would possibly originate from "Soil Re-suspension", whereas Fe, Cu, Rb, La, Ba, Mn, Ti, Ce and Zr were possibly derived from "Brake Wear". As regards the Na, no valid assumption was formulated about the presence of this element in brake wear, while Cr, Sr, Zn were possibly associated with "Tire Wear". Comparatively, V would be suggested as a representative source of fuel consumption, and Pb could possibly belong to "Traffic Pigment". It was noted that the barbican city, surrounded by the Xi'an Ancient City Wall at 12 m high, would trap the trace metal emissions, and consequently increase the health risk for local residents.


Assuntos
Poeira/análise , Metais/análise , Adulto , Carcinógenos , Criança , China , Cidades , Monitoramento Ambiental , Humanos , Metaloides/análise , Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise , Oligoelementos/análise
10.
Environ Monit Assess ; 191(9): 534, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31376029

RESUMO

An assessment of mobility and bioavailability of trace elements present in the soil requires the determination of these elements in soil samples by an appropriate methodology. In such a context, the use of mild extraction reagents-such as water-is considered to be appropriate. On the other hand, performing an analysis of a reference material together with real samples is recommended in order to control the quality of analytical procedure. The quantification of 27 analytes in aqueous extracts of the soil CRMs samples is described. The methodology consisted of single-step extraction of analytes by deionized water (m/v = 1/10) with their subsequent direct determination by inductively coupled plasma-atomic emission spectrometry (ICP-OES). Three certified reference materials (CRM) for soils have been selected as model samples: NCS DC 77302 (alias GBW 07410), Metranal-31, and Metranal-33. Although the recoveries of the selected elements obtained by water extractions are very low (i.e., the values usually do not exceed 1%), the results obtained in this study reveal the elements that by means of ICP-OES can be quantified in the water extracts of unpolluted soils are as follows: Al, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, S, Sr, Ti, and V. However, ICP-OES is not sensitive enough to quantify the elements As, Be, Cd, Co, Pb, Sb, Se, Tl, and Zn that are present in the water extracts of clean soil samples in too low mass fractions. The results obtained in this paper are useful for future uses of the three tested CRMs, in the cases of the extraction of the analytes by deionized water at room temperature.


Assuntos
Monitoramento Ambiental/métodos , Metaloides/análise , Metais/análise , Solo/química , Oligoelementos/análise , Água/química , Extração Líquido-Líquido , Espectrofotometria Atômica
11.
Ecotoxicol Environ Saf ; 183: 109570, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442811

RESUMO

A pot study was conducted to assess the phytoremediation potential of Spinach plants along with their physiological and biochemical response when grown in soil contaminated with heavy metal(loid)s (HMs). Plants were grown under different doses of Pb, Cd and As; and their metal(loid) accumulation efficiency was studied upon harvest; expressed in terms of bioabsorption coefficient (BAC), bioconcentration factor (BCF) and translocation factor (TF). Results showed significant (p ≤ 0.05) difference in physiological and biochemical mechanisms of plants as detected through decrease in concentration of cellular constituents (pigments, carbohydrates, total nitrogen content); and increase in antioxidants (both enzymatic and non-enzymatic). Despite of accumulating high amount of HMs in tissues, no visible signs of toxicity were seen; and hence the efficient survival and defense mechanism shown by spinach plants conclude that they are a viable option to be used for phytoremediation of sites contaminated with Cd and Pb. Since the content of Cd and Pb in edible part was higher than safe limits prescribed by USEPA, the present investigation also highlights the ecological hazards that may result upon cultivation of spinach in contaminated soil for agricultural purpose; or its accidental exposure to food chain when grown for phytoremediation.


Assuntos
Antioxidantes/metabolismo , Metaloides/toxicidade , Metais Pesados/toxicidade , Poluentes do Solo/toxicidade , Spinacia oleracea/efeitos dos fármacos , Agricultura , Biodegradação Ambiental , Ecologia , Metaloides/análise , Metais Pesados/análise , Solo/química , Poluentes do Solo/análise , Spinacia oleracea/crescimento & desenvolvimento , Spinacia oleracea/metabolismo
12.
Environ Sci Pollut Res Int ; 26(25): 25945-25957, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31273653

RESUMO

During the operation of a mine, waste rock is often deposited in heaps and usually left under ambient conditions allowing sulfides to oxidize. To focus on waste rock management for preventing acid rock drainage (ARD) formation rather than ARD treatment could avoid its generation and reduce lime consumption, costs, and sludge treatment. Leachates from 10 L laboratory test cells containing sulfide-rich (> 60% pyrite) waste rock with and without the addition of lime kiln dust (LKD) (5 wt.%) were compared to each other to evaluate the LKD's ability to maintain near neutral pH and reduce the sulfide oxidation. Leaching of solely waste rock generated an acidic leachate (pH < 1.3) with high concentrations of As (21 mg/L), Cu (20 mg/L), Fe (18 g/L), Mn (45 mg/L), Pb (856 µg/L), Sb (967 µg/L), S (17 g/L), and Zn (23 mg/L). Conversely, the addition of 5 wt.% LKD generated and maintained a near neutral pH along with decreasing of metal and metalloid concentrations by more than 99.9%. Decreased concentrations were most pronounced for As, Cu, Pb, and Zn while S was relatively high (100 mg/L) but decreasing throughout the time of leaching. The results from sequential extraction combined with element release, geochemical calculations, and Raman analysis suggest that S concentrations decreased due to decreasing sulfide oxidation rate, which led to gypsum dissolution. The result from this study shows that a limited amount of LKD, corresponding to 4% of the net neutralizing potential of the waste rock, can prevent the acceleration of sulfide oxidation and subsequent release of sulfate, metals, and metalloids but the quantity and long-term stability of secondary minerals formed needs to be evaluated and understood before this method can be applied at a larger scale.


Assuntos
Compostos de Cálcio/química , Poeira/análise , Ferro/química , Metaloides/análise , Óxidos/química , Sulfatos/química , Sulfetos/análise , Concentração de Íons de Hidrogênio , Metaloides/química , Metais/análise , Metais/química , Minerais/análise , Minerais/química , Oxirredução , Sulfetos/química
13.
Bull Environ Contam Toxicol ; 103(2): 308-315, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31190165

RESUMO

In our study, we collected 146 surface soil samples in Xiamen City and measured the concentrations of five heavy metals (Cr, Cu, Pb, Ni, and Zn) and one metalloid (As). Multivariate statistics, geostatistics and Random Forest methods were applied to identify the potential sources and spatial variation of the six elements. The results revealed that As, Cr, and Ni originated mainly from industrial activities, and higher concentrations were found in developed areas. The amounts of Cu, Pb, and Zn in soils were mainly predetermined by soil parent material and agricultural activities. Besides, the atmospheric deposition rather than industrial activities substantially influenced the accumulation of Pb in the soils near the boundary between Tong'an and Quanzhou City, because there were few industries but many forests in this area. Because of the connections of the six elements with factor values of factor analysis, appropriate and accessible covariates could be used in co-kriging to increase the accuracies of interpolation of heavy metal and metalloid concentrations relative to that in ordinary kriging.


Assuntos
Monitoramento Ambiental/métodos , Metaloides/análise , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Agricultura , China , Cidades , Indústrias , Análise Espacial
14.
Environ Geochem Health ; 41(6): 2875-2892, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31230341

RESUMO

Soils from the old Mortórios uranium mine area were studied to look for contamination, as they are close to two villages, up to 3 km away, and used for agriculture. They are mainly contaminated in U and As and constitute an ecological threat. This study attempts to outline the degree to which soils have been affected by the old mining activities through the computation of significant hot clusters, Traditional geostatistical approaches commonly use raw data (concentrations) accepting that the analyzed elements represent the soil's entirety. However, in geochemical studies these elements are just a fraction of the total soil composition. Thus, considering compositional data is pivotal. The spatial characterization, considering raw and compositional data together, allowed a broad discussion about not only the concentrations' spatial distribution, but also a better understanding on the possibility of trends of "relative enrichment" and, furthermore an insight in U and As fate. The highest proportions (compositional data) on U (up to 33%), As (up to 35%) and Th (up to 13%) are reached in the south-southeast segment. However, the highest concentrations (raw data) occur in north and northwest of the studied area, pointing out to a "relative enrichment" toward the south-southeast zone. The Mondego Sul area is mainly contaminated in U and As, but also in Co, Cu, Pb and Sb. The Mortórios area is less contaminated than the Mondego Sul area.


Assuntos
Metaloides/análise , Metais/análise , Mineração , Poluentes do Solo/análise , Solo/química , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Modelos Teóricos , Portugal , Urânio
15.
Environ Geochem Health ; 41(6): 2505-2519, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31049755

RESUMO

The occurrence of toxic metals and metalloids associated with mine tailings is a serious public health concern for communities living in mining areas. This work explores the relationship between metal occurrence (e.g., spatial distribution in street dusts), human health indicators (e.g., metals in urine samples, lifestyle and self-reported diseases) and socioeconomic status (SES) using Chañaral city (in northern Chile) as study site, where a copper mine tailing was disposed in the periurban area. This study model may shed light on the development of environmental and health surveillance plans on arid cities where legacy mining is a sustainability challenge. High concentrations of metals were found in street dust, with arsenic and copper concentrations of 24 ± 13 and 607 ± 911 mg/kg, respectively. The arsenic concentration in street dust correlated with distance to the mine tailing (r = - 0.32, p-value = 0.009), suggesting that arsenic is dispersed from this source toward the city. Despite these high environmental concentrations, urinary levels of metals were low, while 90% of the population had concentrations of inorganic arsenic and its metabolites in urine below 33.2 µg/L, copper was detected in few urine samples (< 6%). Our results detected statistically significant differences in environmental exposures across SES, but, surprisingly, there was no significant correlation between urinary levels of metals and SES. Despite this, future assessment and control strategies in follow-up research or surveillance programs should consider environmental and urinary concentrations and SES as indicators of environmental exposure to metals in mining communities.


Assuntos
Poeira/análise , Exposição Ambiental/análise , Metais/urina , Mineração , Adolescente , Adulto , Idoso , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/urina , Arsênico/análise , Arsênico/urina , Chile , Cidades , Cobre/análise , Cobre/urina , Estudos Transversais , Saúde Ambiental , Monitoramento Ambiental/métodos , Feminino , Humanos , Masculino , Metaloides/análise , Metais/análise , Pessoa de Meia-Idade , Fatores Socioeconômicos , Adulto Jovem
16.
Environ Sci Pollut Res Int ; 26(20): 20712-20730, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31104229

RESUMO

The best available technology for preventing the formation of acid drainage water from the sulfidic waste rock at mine closure aims to limit the oxygen access to the waste. There is, however, a concern that contaminants associated with secondary minerals become remobilized due to changing environmental conditions. Metal(loid) mobility from partially oxidized sulfidic waste rock under declining and limited oxygen conditions was studied in unsaturated column experiments. The concentrations of sulfate and metal(loid)s peaked coincidently with declining oxygen conditions from 100 to < 5 sat-% and to a lesser extent following a further decrease in the oxygen level during the experiment. However, the peak concentrations only lasted for a short time and were lower or in the similar concentration range as in the leachate from a reference column leached under atmospheric conditions. Despite the acid pH (~ 3), the overall quality of the leachate formed under limited oxygen conditions clearly improved compared with atmospheric conditions. In particular, the release of As was two orders of magnitude lower, while cationic metals such as Fe, Cu, Mn, and Zn also decreased, although to a lesser extent. Decreased sulfide oxidation is considered the primary reason for the improved water quality under limited oxygen conditions. Another reason may be the immobility of Fe with the incorporation of metal(loid)s in Fe(III) minerals, in contrast to the expected mobilization of Fe. The peaking metal(loid) concentrations are probably due to remobilization from solid Fe(III)-sulfate phases, while the relatively high concentrations of Al, Mn, and Zn under limited oxygen conditions were due to release from the adsorbed/exchangeable fraction. Despite the peaking metal(loid) concentrations during declining oxygen conditions, it is clear that the primary remediation goal is to prevent further sulfide oxidation.


Assuntos
Recuperação e Remediação Ambiental/métodos , Metaloides/química , Metais/química , Oxigênio/análise , Poluentes Químicos da Água/química , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Metaloides/análise , Metais/análise , Minerais/análise , Minerais/química , Oxirredução , Sulfetos/química , Poluentes Químicos da Água/análise
17.
Artigo em Inglês | MEDLINE | ID: mdl-31126009

RESUMO

A total of 43 water and sediment samples, and 34 Corbicula fluminea samples were collected in Xijiang River in southern China to determine the spatial distribution and sources of 12 metals/metalloids (V, Co, Cr, Ni, Cu, Mn, Zn, Cd, Pb, As, Sb, and Tl) and to assess the pollution levels and ecological risks of the pollutants. The results showed that the levels of the metals/metalloids (except for Tl) in the river water from almost all of the sampling sites met the Chinese national surface water quality standards. However, the concentrations of the metals/metalloids in the sediments exceeded the background values by a factor of 1.03-56.56 except for V, Co, and Mn, and the contents of Zn, Cd, and Pb in the Corbicula fluminea soft tissue exceeded the limits of the Chinese Category I food Quality Standards. The spatial distribution analysis showed that the concentrations of the contaminants in the lower reaches of Xijiang River were higher than in the upper reaches. The bioaccumulation factor (BAF), biota-sediment accumulation factor (BSF), geo-accumulation index (Igeo), and the potential ecological risk index (RI) were obtained to assess the pollution levels and ecological risks. The results indicated that Cu, Cd, and Zn were the most prone to bio-accumulation in the Corbicula fluminea soft tissue, and the lower reaches showed a much higher pollution level and risk than the upper reaches. The metals/metalloids in the sediments posed serious threat on the aquatic ecosystem, of which Cd, As, and Sb are the most risky contaminants. The results of principal component analysis (PCA) indicated Cr, Ni, Cu, Mn, Cd, Pb, and As in the sediments came from relevant industrial activities, and V and Co originated from natural sources, and Sb from mining activities, Zn and Tl came from industrial activities and mining activities.


Assuntos
Poluição Ambiental/análise , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Metaloides/análise , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Animais , China , Corbicula , Monitoramento Ambiental/métodos , Mineração , Medição de Risco/métodos , Análise Espacial
18.
Environ Pollut ; 250: 323-330, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31003144

RESUMO

The chemical composition of the uropygial gland secretion of birds shows seasonal, sex and age-related variations following sex hormones fluctuations. We explore the use of the composition of the uropygial gland secretion as a non-invasive biomarker of endocrine disruption in 137 common moorhens (Gallinula chloropus) from Navaseca Pond, which receives the effluent of a wastewater treatment plant, and from the more pristine Tablas de Daimiel National Park in Spain. Wax ester and fatty acid compositions were measured by means gas chromatography - mass spectrometry (GC-MS) in the uropygial gland secretion of moorhens from both wetlands. Organochlorine compounds (p,p'-DDE and PCBs) were measured in blood and uropygial gland secretion of moorhens as indicators of anthropogenic pollutants, and this information was interpreted together with previous results of the accumulation of metals and metalloids in blood and feathers of these moorhens and a wide range of endocrine disrupting chemicals (EDCs) measured in water from both study sites. PCBs and p,p'-DDE were found in 32% of the blood and 51% of uropygial gland secretion samples, being at highest levels in Navaseca. Wax composition was dominated by monoesters of 35-38 carbons and displayed a clear seasonal variation, in which long-chain wax esters were more abundant in spring-summer than in autumn-winter. This seasonal change was less evident in birds from Navaseca, where the presence of shorter wax esters was associated with the higher concentration of PCBs in uropygial gland secretion. The observed effect may not be associated with this specific type of pollutants because moorhens in Navaseca are also exposed to a wide diversity endocrine disruptors as shown in a previous study. Uropygial gland secretion can be a useful non-invasive sample for integrating chemical monitoring of pollutants and their effects as endocrine disruptors in birds.


Assuntos
Biomarcadores/metabolismo , Aves/fisiologia , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental/métodos , Ésteres/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/análise , Disruptores Endócrinos/análise , Ésteres/análise , Plumas/química , Cromatografia Gasosa-Espectrometria de Massas , Metaloides/análise , Metais/análise , Estações do Ano , Esgotos/análise , Espanha , Águas Residuárias/análise , Áreas Alagadas
19.
Artigo em Inglês | MEDLINE | ID: mdl-30929561

RESUMO

High-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was applied to the speciation of arsenic [As(III), As(V), and AsB (arsenobetaine)], MMA (monomethylarsonic acid), DMA (dimethylarsinic acid), antimony [Sb(III) and Sb(V)], and chromium [Cr(III) and Cr(VI)] in water and bottom sediment samples collected from the urban Bytomka River (Poland). The main objective of the study was the research of As, Cr and Sb species in the Bytomka River, as well as the simplified three-stage sequential chemical extraction of bottom sediments according to the Institute for Reference Materials and Measurements (BCR). The contents of V, Mn, Co, Ni, Cu, Zn, Rb, Sr, Ag, Cd, Te, Ba, Tl, Pb, Fe, Ga, and U in the water and bottom sediments were tested using the ICP-MS technique. The risk assessment code (RAC) indicated a medium risk for As and a high risk for Sb to the environment. Sequential chemical extraction of bottom sediments showed that As and Cr were strongly demobilized. Sb was mainly bound with the ion-exchange fraction and posed a serious threat to the environment. Chemometric analysis with the (dis)similarity analysis and principal component analysis (PCA) allowed for visualization of the variability and correlations of the analyzed elements.


Assuntos
Monitoramento Ambiental , Resíduos Industriais/análise , Metaloides/análise , Metais/análise , Rios/química , Poluentes Químicos da Água/análise , Antimônio/análise , Arsênico/análise , Arsenicais/análise , Ácido Cacodílico/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromo/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Humanos , Espectrometria de Massas/métodos , Polônia , Análise de Componente Principal , Águas Residuárias/análise , Água/química
20.
Environ Monit Assess ; 191(5): 264, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30953206

RESUMO

A baseline environmental characterization of Chrome and Dogfish bays on the Kenai Peninsula, Alaska, was conducted using a sediment quality triad approach. Resident fish and blue mussel body burdens were also assessed. The data was derived from a larger study that assessed seven distinct water bodies on the Kenai Peninsula's north side, draining into Kachemak Bay. Sampling sites for water quality measurements and sediment were randomized within each embayment. Concentrations of 140 organic and elemental contaminants were analyzed. Habitat parameters (depth, salinity, temperature, dissolved oxygen, sediment grain size, and organic carbon content) that influence elemental distribution were also measured at each sampling site. Chrome Bay and Dogfish Bay open into lower Cook Inlet and had coarser sediments than the other bays studied. Concentrations of chromium and nickel were extremely high in Chrome Bay. Concentrations were several times higher than observed concentrations seen throughout other locations in south-central Alaska. Other elemental concentrations varied between and within bays, with several locations exceeding lower sediment quality guidelines. Whole sediment amphipod toxicity bioassays were conducted with sediments from Chrome Bay. No sample exhibited significant mortality or sublethal effects. Body burdens of three species of fish and mussels collected in Chrome Bay did not exhibit elevated concentrations relative to other studies in Kachemak Bay or the Alaska Dept. of Environmental Conservation, Fish Monitoring Program. Despite the very high concentrations of Cr and Ni in the sediments, the metals do not appear to be bioavailable to resident biota.


Assuntos
Cromo/análise , Sedimentos Geológicos/química , Metaloides/análise , Metais/análise , Níquel/análise , Poluentes Químicos da Água/análise , Alaska , Animais , Baías , Bivalves/química , Carga Corporal (Radioterapia) , Ecossistema , Monitoramento Ambiental , Estuários , Peixes , Salinidade
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