Total arsenic, lead, cadmium, copper, and zinc in some salt rivers in the northern Andes of Antofagasta, Chile

The pre-Andes water in the region of Antofagasta is the main drinking and i rrigation water source for approximately 3000 Atacamena (indigenous) people . The concentration for soluble elements (filtration in field through a 0.4 5-mu m filter) was: Cd < 0.1 ng/ml; Pb < 0.5 ng/ml; and Zn and Cu between 1 and 10 ng/ml. In particulate material the concentrations were: for Cd < 0. 1 ng/ml; for Ph < 0.3 ng/ml; and for Zn and Cu less than 1 ng/ml. The total content of these elements is far below the international recommendations ( WHO) and the national standards (N. Ch. 1333 mod. 1987 and 409-1 of 1984). On the other hand, in some rivers a very high arsenic concentration was fou nd (np to 3000 ng/ml) which exceed more than 50 times the national standard . In order to verify the analytical results, inter-laboratory and compariso n with different determination methods have been done. (C) 2000 Elsevier Sc ience B.V. All rights reserved.