| Abstract: | Some typical and more frequent freshwater invertebrates of running waters were studied to examine the influence of styrene, xylene and benzene on their mortality. Snails Amphimelania holandri FÉR. and Lymnaea stagnalis L. and crustacenas Asellus aquaticus L. and Gammarus fossarum KOCH. , were used in the semi-static test. Compounds were added in volume concentrations of 0.005 to 0.4% v/v. For all concentrations LC50 was calculated by probit method, which demonstrated that mortality depends much more on increased concentrations (depending on the initial concentration) than on the length of exposure. Styrene was the most toxic, followed by xylene and then benzene. The species G. fossarum showed marked sensitivity, followed by A. aquaticus, and the species A. holandri and L. stagnalis showed less sensitivity. |
