Fenbutatin acute toxicity on Artemia nauplii: effects of sublethal concentrations on ATPase activity.

Abstract

During the last decades, the use of organotin compounds has steadily increased. The numerous applications of these compounds are primarily in industry as stabilizers for PVC, in agriculture as miticides and fungicides and in the marine environment as antifoulants. The increasing annual usage of organotin compounds raises the possibility of environmental pollution. The toxicity and degradation of organotins in the environment depends strongly on the number and nature of substituents (Muller 1987). In water, triphenyltin compounds decompose slowly (Bock 1981). Persistence of at least 8 months was found when triphenyltin was used against water snails at concentration of 1.0 ppm ( Deschiens and Floch 1963). Organotin compounds in the aquatic environment accumulate in the microlayer of the water surface, are readily adsorbed in sediments and on suspended particulates (Chernega et al. 1971, Cooney and Wuertz 1989). The half-life of organotins was found to be up to 5 months in freshwater sediments (Maguire and Tkacz 1985) and up to 2 years in deep and anaerobic estuarine sediments (Waldock et al.1990). Among organotins trisubstituted compounds are generally the most toxic to fish, to microorganisms and to other aquatic inhabitants (Bock 1981, Cooney and Wuertz 1989). Whereas the adverse effects of tributyltin, the main representative of antifouling agents , on the homeostasis of the aquatic ecosystems has been studied, few data are available concerning the environmental impact of the trisubstituted organotins used in agriculture as miticides. The aim of this project is to determine the median lethal concentration of the organotins used as miticides, in nauplii of the marine crustacea Artemia and to study the effects of sublethal concentrations on the activity of ATPase enzymatic system. In this study we will present the results from the experimentation with fenbutatin on the survival and ATPase activity of Artemia nauplii.