Health risk assessment by exposure to arsenic in water in rural locations of the Arica Parinacota Region, Chile

Abstract

Introduction: Prolonged exposure to arsenic (As) through drinking water is linked to various ne-gative health effects. This study aimed to assess the potential systemic risk (Hazard Quotient, HQ) and the carcinogenic risk (Carcinogenic Risk, CR) associated with chronic arsenic intake in in-fants, children, and adults living in rural areas of the communes of the Arica and Parinacota Region.

Materials and Methods: The concentration of arsenic (As) was analyzed using mass spectrometry in 294 water samples collected from 2018 to 2019. The average dai-ly intake of arsenic through water, along with associated risk indices, was calculated ba-sed on methodologies recommended by the United States Environmental Protection Agency.

Results: Notably, 36.7% of the samples exceeded the Chilean standard for arsenic concentration, set at 0.01 mg/L. The average arsenic (As) concentration exceeded the standard across all communes, ranked in decreasing order as follows: Camarones, Putre, General Lagos, and Arica. When examining the type of water supply, the order of exceedance was as follows: Precarious System (PS) > Well (PA) > Rural Drinking Water (RDW). The hazard quotients (HQ) for each commune were greater than 1, and cancer risk (CR) values ranged from 8.84 to 336 times above reference values across all age groups. In terms of water supply type, HQ values ranged from 1.06 to 55.8 times above 1, with the exception of adults and children receiving water from Camión Aljibe (CA). CR values were greater than 1x10^-4, ordered as follows: SP > PA > APR > CA.

Discussion: The localities studied exhibit a significant risk of adverse health effects due to chronic expo-sure to arsenic. Urgent measures are needed to enhance water quality and to maintain epidemiological surveillance in these communities.