SPERM CELL BIOASSAYS WITH THE SEA-URCHIN ARBACIA-SPATULIGERA ON SAMPLES FROM 2 POLLUTED CHILEAN COASTAL SITES

A short-term sea urchin sperm cell bioassay was developed using Arbaci a spatuligera from Chilean waters. Sperms of this species were exposed to serially diluted effluent and seawater samples from two polluted l ocalities: Lenga Beach (San Vicente Bay) and Rocuant Beach (Bay of Con cepcion). Both bays receive point-source discharges of municipal waste waters, and effluents from several chemical, steel and fishmeal facili ties. Statistically significant reductions in fertilization were found at both sites. Rocuant 4 and Rocuant 5 showed strong effects on ferti lization and Rocuant 3 showed no significant effect on fertilization. Also, Rocuant test waters at sites 1, 2 and 6 showed significant effec ts on fertilization. No observable effect concentrations (NOEC) from R ocuant waters were estimated as 12.5% (Rocuant 1), 50% (Rocuant 2) and 6.25% (Rocuant 6). The 100% and 50% concentrations of test water from Lenga 1 showed a consistent reduction of fertilization with NOEC 12.5 %. The sperm cell bioassay with A. spatuligera was found to be fast, e asy to conduct, and a sensitive indicator of both organic waste and ch emical pollution. It was concluded that this is a useful procedure for the biomonitoring of marine waters.