Short-term toxicity tests on the harpacticoid copepod Tisbe battagliai: lethal and reproductive endpoints.

Short-term bioassays based on lethal and reproductive responses of Tisbe battagliai were applied to determine responses of copepods to copper and LAS. Percentage of spawning females, fecundity (F), and total newborn production (N) for 48 and 72 h were calculated for both substances. It was observed percentage of spawning females was not affected by sublethal concentrations of both compounds. Following values were obtained: EC(50)(N)-48 h of 670+/-30 microgLASL(-1) and EC(50)(F)-48 h of 670+/-30 microgLASL(-1); and EC(50)(N)-72 h of 44.5+/-1.8 microgCuL(-1) and EC(50)(F)-72 h of 30.8+/-1.1 microgCuL(-1). Lethal effects of the two substance-types were also assessed, obtaining the LC(50)-24h of 1980+/-160 microgLASL(-1); and LC(50)-48 h of 83.1+/-10.5 microgCuL(-1) for nauplii; and LC(50)-72 h of 157+/-25 microgCuL(-1), and LC(50)-72 h of 2660+/-270 microgLASL(-1) for adults. Fecundity and total newborn production are sensitive endpoints for determining effects of toxicants.