Hair arsenic of a low risk population in General Pico, La Pampa, Argentina

Abstract

Arsenic is a widely spread element in the environment. The continuous exposure to this element causes chronic poisoning. In the province of La Pampa, Argentina, there are wide zones where the underground water contains a high rate of arsenic. In humans, inorganic arsenic suffers methylation in the liver, a fact considered as a detoxifying mechanism. The efficiency of this mechanism depends on the oxidation state and on the dose. Hence, when saturation is produced, it begins to accumulate in the hair. There have been discussions and uncertainties as regards the relation between arsenic and cancer risk evaluations. The question most frequently raised is whether or not it is correct to adopt international standards without previous physiological and ecotoxicological studies in the specific population where arsenic is being studied. In the present work, we show the results of the measurements of arsenic in the hair of the inhabitants of General Pico, La Pampa, a population considered under risk because arsenic level in drinking water is 0.110 ± 0.034 mg/l, higher than 0.010 mg/l, maximum level accepted by the Código Alimentario Argentino. The average value of arsenic in hair found was of 0.183 ± 0.093 mg/kg, a value close to 0.200 mg/kg, which is considered the upper threshold in unexposed populations. We also found that male individuals and individuals younger than 20 years had the highest average arsenic values (0.255 ± 0.106 and 0.238 ± 0.143 mg/kg, respectively).