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Human health risk assessment of metals and anions in surface water from a mineral coal region in Brazil

Abstract

Coal mining releases high concentration elements to the environment, which can be deposited in surface water, causing several human health problems. Candiota mine in the south of Brazil is the largest coal reserves in the country, representing approximately 40% of total national coal reserves. Therefore, the present study aimed to estimate the chronic daily dose and the non-carcinogenic risk index for metals and anions in surface waters of Candiota Region, using the USEPA protocols for Human Health Risk Assessment. A total of eight water samples were collected over a distance of up to 15 km from the emission sources of the thermal power generation companies, then the Chronic Daily Intake (CDI), Hazard Quotient (HQ), Hazard Index (HI), and sum of Hazard Index (ΣHI) were calculated. All the elements and anions evaluated showed natural concentrations for continental fresh waters according to Brazilian legislation, except Pb. Individually, none of the metals Pb, As, Cd, Ni, and Se or anions F and NO3 showed an HI value greater than 1. However, the sum of HI (ΣHI) (five metals and two anions) by sample point showed values close to 1, for one of the eight points analyzed. Pb and Fe were the elements that most contribute to the risk values in the sample points of the study area. Although, there is no human health risk in this scenario, this investigation highlight priority elements to future investigations in coal mine areas. In the current region, Pb and F as priority elements for future studies.

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Funding

This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-Brasil (CAPES)-Finance Code 001, the Institutional Program for Internationalization (CAPES-PrInt), Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS) and Conselho Nacional de Desenvolvimento Científico e Tecnológico-310856/2020–5.

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ASB, RLB, and PFR were responsible for collecting and interpreting the data, preparing the maps and writing the text. MS and IML were responsible for reviewing the data, analyzing, and interpreting the data. RAT was responsible for reviewing the equations, calculations, and values used in the Risk Assessment model. FMRSJ was the study supervisor. All authors read and approved the final manuscript.

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Correspondence to Flavio Manoel Rodrigues da Silva Júnior.

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da Silva Bonifácio, A., de Lima Brum, R., Tavella, R.A. et al. Human health risk assessment of metals and anions in surface water from a mineral coal region in Brazil. Environ Monit Assess 193, 567 (2021). https://doi.org/10.1007/s10661-021-09359-6

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Keywords

  • Brazil
  • Candiota
  • Coal mining
  • Lead
  • Fluoride