Water and sediment ecotoxicity studies in Temuco and Rapel River Basin,Chile

Five samples were collected from the Rapel River Basin near the city of Rancagua and three from the city of Temuco. Three of the samples were collected from raw drinking water supplies. The following bioassays were performed on some or all of the samples: Microtox; Microtox solid phase test; SOS-Chromotest with and without S9; Toxi-Chromotest; Sediment-Chromotest; Panagrellus redivivus percent survival and percent maturation; submitochondrial reverse electron transfer and forward electron transfer tests; Daphnia magna 24 h acute toxicity; ECHA biocide monitor, and the competitive immunoassay tests for benomyl, metolachlor, atrazine, and triazines. All the sampling sites were positive for the presence of genotoxicants requiring S9 activation while three sites also indicated the presence of direct-acting genotoxicants/mutagens (−S9). Also, all the sites were positive for the presence of pesticides. In some samples there was 100% inhibition of P. redivivus maturation. Details and discussion on the implication of the results are presented. © 1996 by John Wiley & Sons, Inc.