EXPERIMENTAL-STUDY OF BIOACCUMULATION AND EFFECTS OF THE HERBICIDE ISOPROTURON ON FRESH-WATER ROOTED MACROPHYTES - (ELODEA DENSA AND LUDWIGIA NATANS)

Bioaccumulation and effects of the herbicide Isoproturon (IPU) on two freshwater rooted macrophytes Elodea densa and Ludwigia natans were st udied after direct exposure via the water column in indoor microcosms. Three complementary experiments were set up, based on two [IPU] range s (0-1000 and 0-100 mu g.L(-1) - 6 points/range) and on a chronologica l approach (1.5, 4, 9 and 21 days). The results showed a significant g rowth inhibition of the E. densa cuttings for an [IPU] close to 10 mu g.L(-1). Oxygen concentrations in the medium were weakly but significa ntly reduced after 24 h exposure to 2 mu g.L(-1). IPU bioaccumulation revealed a clear saturation process in the low range of [IPU] in the w ater, with maximal BCF values close to 60 at 2 mu g.L(-1). (C) 1996 El sevier Science Ltd.