EVALUATION OF PESTICIDES USED IN GOLF LIN KS BY ACUTE TOXICITY TEST ON RAINBOW-TROUT

To assess the effects of pesticides sprayed in golf links on aquatic o rganisms, twenty pesticides were assayed by acute toxicity test using rainbow trout Oncorhynchus mykiss. Susceptibility to several pesticide s, i.e. captan, chlorothalonile, chlorpyrifos, diazinon, and fenitroth ion, was measured at different developmental stages: embryo, sac fry, and fry. No remarkable difference in susceptibility was observed among developmental stages on four pesticides except for chlorpyrifos, whic h showed a remarked difference in susceptibility among the different s tages. Of the 20 chemicals tested, the 96 hour median lethal concentra tion (96 h-LC(50)) of less than 0.1 mg/l was obtained in captan, chlor othalonile, thiuram, chlorpyrifos, and oxine-copper. On the other hand , 96 h-LC(50) exceeding 10 mg/l was obtained in flutolanil, mepronil, benfluralin, and mecoprop. The 96 h-LC(50) values of several pesticide s were lower than the current effluent guideline values for golf links , suggesting that the guideline value is inadequate to conserve fishes in natural waters.