Spatial and temporal variations in arsenic exposure via drinking-water in Northern Argentina

This study evaluated the spatial, temporal and inter-individual variations in exposure to arsenic via drinking-water in Northern Argentina, based on measurements of arsenic in water, urine, and hair.. Arsenic concentrations in drinking-water varied markedly among locations, from < 1 to about 200 mu g/L. Over a 10-year period, water from the same source in San Antonio de los Cobres fluctuated within 140 and 220 mu g/L, with no trend of decreasing concentration. Arsenic concentrations in women's urine (3-900 mu g/L, specific weight 1.018 g/mL) highly correlated with concentrations in water on a group level, but showed marked variations between individuals. Arsenic concentrations in hair (range 20-1,500 mu g/kg) rather poorly correlated with urinary arsenic, possibly due to external contamination. Thus, arsenic concentration in urine seems to be a better marker of individual arsenic exposure than concentrations in drinking-water and hair.