ACUTE TOXIC EFFECTS OF ORGANOTIN COMPOUNDS ON BENTHIC ORGANISMS - TUBIFEX TUBIFEX AND CHIRONOMUS-PLUMOSUS

To investigate their ecotoxicological effects, diorganotin and triorga notin compounds were tested by using benthic organisms Tubifex tubifex and Chironomus plumosus. The acute toxicological effects of organotin compounds (OTCs) as LC(50) values and their 95% confidence limits wer e calculated by using probit analysis for mortality. The following OTC s were tested: A - dibutyltin bis-N,N-diethyldithiocarbamate, B - dime thyltin bis-N,N-diethyldithiocarbamate, C - triphenyltin chloride, D - triphenyltin acetate, E - triphenyltin N,N-diethyldithiocarbamate, F - tribenzyltin bis-N,N- diethyl-dithiocarbamate, G - tribenzyltin chlo ride, H - bis-tributyltin 3,4,5,6-tetrachlorphthalate, I - tributyltin sulphaminate, J - tributyltin N,N-diethyldithiocarbamate, K - tributy ltin oxide (TBTO). From the LC(50) values the following rank orders of toxicity were established: T. tubifex: K > J > G > E > D > C > F > A > I > H > B, Ch. plumosus: I > J > K > C > D = E > A = G > H > F > B. Ch. plumosus was more sensitive to ail tested compounds than T. tubife x except for compound G.