Table 1.

Historical arsenic concentrations in drinking water in the study area by year

Average arsenic concentration, μg/L
Years
RegionCity or townPopulationa1930–19571958–19701971–19771978–19791980–19871988–19941995+
IArica168,5941010101010109
Putre1,7991111111
Iquique196,94160606060606010
Huara2,36530303030303030
Pica5,62210101010101010
Pozo Almonte9,85540404040404040
IITocopilla21,8272502506361101104010
Maria Elena6,8522502506361101103939
Calama125,9461501502871101104038
San Pedro4,522600600600600600600600
Antofagasta270,18490860110110704010
Mejillones7,66090860110110703710
Taltal10,10160606060606060
Recent migrants82,312<10<10<10<10<10<10<10
  • aPopulation data are based on the most recent Chile census (ref. 10).