TRANSPORTATION OF PESTICIDES IN ESTUARIES OF LOUROS AND ARACHTHOS RIVERS (AMVRAKIKOS GULF, NW GREECE)

Water and sediment samples from seven stations in estuaries of the Louros and Arachthos rivers as well as in the wetlands of the Amvrakikos Gulf were collected for a period from March 1992 to February 1993. The herbicides atrazine, simazine, alachlor, metolachlor, trifluralin and diuron and the organochlorine insecticides alpha-BHC, lindane and 4,4'-DDE were detected in riverine estuaries and wetlands. The highest concentrations of herbicides, atrazine, simazine, alachlor, metolachlor, diuron and trifluralin in water samples were detected during the period from March to August. The same herbicides and organochlorine insecticides as well as the beta-BHC and 4,4'-DDT were found in significant amounts in sediments of river estuaries and wetlands of the Amvrakikos Gulf. The percentage of total amount of detected pesticides released through the rivers into Amvrakikos Gulf are estimated as 3.1% for atrazine, 1.7% for simazine, 1.9% for diuron, 0.3% for metolachlor, 0.9% for alachlor, 0.3% for lindane and 0.6% for trifluralin.