Health risk assessments of arsenic and toxic heavy metal exposure in drinking water in northeast Iran

BACKGROUND@#Arsenic and heavy metals are the main cause of water pollution and impact human health worldwide. Therefore, this study aims to assess the probable health risk (non-carcinogenic and carcinogenic risk) for adults and children that are exposed to arsenic and toxic heavy metals (Pb, Ni, Cr, and Hg) through ingestion and dermal contact with drinking water.@*METHOD@#In this study, chemical analysis and testing were conducted on 140 water samples taken from treated drinking water in Mashhad, Iran. The health risk assessments were evaluated using hazard quotient (HQ), hazard index (HI), and lifetime cancer risk (CR).@*RESULTS@#The results of the HQ values of arsenic and heavy metals for combined pathways were below the safety level (HQ < 1) for adults, while the HI for children were higher than the safety limit in some stations. Likewise, Cr showed the highest average contribution of HI (55 to 71.2%) for adult and children population. The average values of total carcinogenic risk (TCR) through exposure to drinking water for children and adults were 1.33 × 10 and 7.38 × 10, respectively.@*CONCLUSION@#Overall, the CR through exposure to drinking water for children and adults was borderline or higher than the safety level of US EPA risk, suggesting the probability of carcinogenic risk for the children and adults to the carcinogenic elements via ingestion and dermal routes. Therefore, appropriate purification improvement programs and control measures should be implemented to protect the health of the residents in this metropolitan city.

Heavy Metals Concentration in Fish Mugil cephalus from Machilipatnam Coast and Possible Health Risks to Fish Consumers.

Heavy metals are dangerous to aquatic organisms and it can be bioaccumulated in the food chain leading to diseases in humans. Cumulative effects of metals or chronic poisoning may occur as a result of long term expore even to low concentrations. The accumulation of heavy metals conditions depending upon the species, environmental conditions and inhibitory processes. Considering the human health risk due to the consumption of fish, the concentration of heavy metals (Zn, Pb, Mn, Cu, Cr and Hg) are investigated in fish samples collected from the Machilipatnam coast. The fish was examined for metal constituents are the basis on the human nutrition in the study area. These metal concentrations were exceeding the limits set by the world health organization (WHO). The study provides an insight into the potential impact of increased levels of metals in the environmental as well as estimated of the contaminated of fish tissues with metals.

Health Risks to Children and Adults Residing in Riverine Environments where Surficial Sediments Contain Metals Generated by Active Gold Mining in Ghana

The purpose of this study was to investigate the current status of metal pollution in the sediment from rivers, lakes, and streams in active gold mining districts in Ghana. Two hundred and fifty surface sediment samples from 99 locations were collected and analyzed for concentrations of As, Hg, Cr, Co, Cu, Fe, Zn, Pb, Cd, Ni, and Mn using inductively coupled plasma-mass spectroscopy (ICP-MS). Metal concentrations were then used to assess the human health risks to resident children and adults in central tendency exposure (CTE) and reasonable maximum exposure (RME) scenarios. The concentrations of Pb, Cd, and As were almost twice the threshold values established by the Hong Kong Interim Sediment Quality Guidelines (ISQG). Hg, Cu, and Cr concentrations in sediment were 14, 20, and 26 times higher than the Canadian Freshwater Sediment Guidelines for these elements. Also, the concentrations of Pb, Cu, Cr, and Hg were 3, 11, 12, and 16 times more than the Australian and New Zealand Environment and Conservation Council (ANZECC) sediment guideline values. The results of the human health risk assessment indicate that for ingestion of sediment under the central tendency exposure (CTE) scenario, the cancer risks for child and adult residents from exposure to As were 4.18 x 10(-6) and 1.84 x 10(-7), respectively. This suggests that up to 4 children out of one million equally exposed children would contract cancer if exposed continuously to As over 70 years (the assumed lifetime). The hazard index for child residents following exposure to Cr(VI) in the RME scenario was 4.2. This is greater than the United States Environmental Protection Agency (USEPA) threshold of 1, indicating that adverse health effects to children from exposure to Cr(VI) are possible. This study demonstrates the urgent need to control industrial emissions and the severe heavy metal pollution in gold mining environments.

Riscos à saúde em áreas contaminadas: contribuições da teoria social / Health risk in contaminated area: social theoretical contributions

Este artigo versa sobre contribuições da teoria social a um estudo sobre o risco à saúde humana e ao ambiente, desenvolvido entre 2003 e 2005 em área urbana contaminada, localizada no bairro Vila Carioca, no sudeste do município de São Paulo, Brasil. Resíduos perigosos provenientes de processo produtivo do setor químico, dispostos inadequadamente na localidade ao longo do tempo, resultaram em contaminação ambiental, cujos efeitos representam riscos à saúde da população local. A investigação foi realizada com o objetivo de identificar interpretações sociais sobre o conceito de situação de risco, condizentes com concepções incorporadoras da dimensão social do risco e voltadas à melhoria das condições de saúde ambiental. Utilizou-se metodologia qualitativa de pesquisa, alicerçada na teoria social, e instrumentos variados de coleta de dados. Os resultados apontaram interpretações sociais diferenciadas sobre o conceito de situação de risco, sugerindo diversidade de concepções entre a população pesquisada a respeito dos problemas ambientais e de saúde que os atingiam. Neste artigo, apresentam-se fundamentos do enfoque do risco, na teoria social e na obra de Ulrick Beck sobre sociedade de risco, a fim de conferir suporte teórico à interpretação dos dados coletados em campo. Tais contribuições da teoria social, em contraponto com abordagens multidisciplinares e ecossistêmicas em saúde e ambiente, são discutidas como forma de incorporar a diversidade de interpretações sociais expressadas pela população, no sentido de favorecer a inter-relação entre portadores de risco e decisões políticas locais sobre a questão do risco, ampliar o escopo dos fenômenos observados e propiciar a busca de melhores condições de saúde dos indivíduos e da qualidade do seu ambiente.

Hazardous wastes from chemical productive process, which were disposed in inadequate way throughout the time resulting in contamination of an urban area, which is situated in Vila Carioca, southeast of São Paulo city (Brazil). This environmental contamination has effects that represent health risk to the local population. An investigation in this area, from 2003 to 2005, had as a goal to identify social interpretations about the concept of risk situation (perception). In relation with its social dimension, conceptions of risk in order to improve methodology were used; it is supported by social theory and a variety of instruments for data collection, and it is covered by Ulrick Beck's work about risk society. The results obtained led to distinct social interpretations in relation to risk situation (perception). These results suggested diversity of conceptions in the studied population. In this paper, the focus of discussion is for an adoption of multidisciplinary and use of ecosystemic approach in studies and interventions that involve health risk, and thus evidences the relationship between population at-risk and local political decisions.