Human health risk assessment for ingestion exposure to groundwater contaminated by naturally occurring mixtures of toxic heavy metals in the Lao PDR.
Environ Monit Assess
; 186(8): 4905-23, 2014 Aug.
Article
em En
| MEDLINE
| ID: mdl-24760657
ABSTRACT
This study constitutes the first systematic risk assessment in the Lao PDR of the safety of groundwater for consumption. Groundwater and hair samples were collected from seven Lao provinces to determine the quantitative health impact of heavy metals through ingestion exposure. Contamination levels for arsenic (As; 46.0 %) and barium (Ba; 16.2 %) exceeded World Health Organization (WHO) guidelines, especially in Mekong River floodplains. A USEPA assessment model for health risks from daily groundwater ingestion, with adjustments for local water consumption values, was applied to estimate the size of the population at risk for noncarcinogenic and carcinogenic health problems. As was the only element contributing to noncarcinogenic health risks in all contaminated areas. The populations of Bolikhamxai, Savannakhet, Saravane, Champasak, and Attapeu, moreover, were at risks of cancer. In addition to the As groundwater concentration factor, noncarcinogenic and carcinogenic risks were positively correlated with the average daily dose of As, exposure duration, and subject body weight. The level of As in hair correlated with groundwater consumption and average daily dose of As. 25.5 % of the population (n = 228) showed As levels in hair above the toxicity level.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Água Subterrânea
/
Metais Pesados
/
Exposição Ambiental
Tipo de estudo:
Etiology_studies
/
Prognostic_studies
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Risk_factors_studies
Limite:
Humans
País/Região como assunto:
Asia
Idioma:
En
Revista:
Environ Monit Assess
Assunto da revista:
SAUDE AMBIENTAL
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Tailândia