Biological effects of tributyltin on the caprellidea (Crustacea: Amphipoda)

Abstract

During the past several decades, butyltin compounds (BTs), one of the representative groups of organotin compounds (OTs), have been widely used as an antifouling agent in paints for boats, ships, and aquaculture nets (Fent 1996, Champ and Seligman 1996), thus these compounds have been found in a variety of marine organisms, often at concentrations exceeding acute or chronic toxicity levels (Bryan and Gibbs 1991; Alzieu 1996). The hazardous effects of antifouling paints containing BTs in marine ecosystem have become a significant environmental issue all over the world (Champ and Wade 1996; Bosselmann 1996). To prevent the destruction of marine ecosystems, BT application to small boats and fish farming equipment has been banned or regulated in developed countries since the late 1980s (Champ and Wade 1996; Bosselmann 1996). Nevertheless, significant accumulation of BTs has been noted at various trophic levels in the marine food chain including plankton, algae, crustaceans, fishes and cetaceans, indicating that BTs impact continues to be felt in marine ecosystems. Tri-organotins, tributyltin (TBT) are reported to be the most toxic compounds, and at nanogram-per-liter levels, TBT has adverse effects on many aquatic organisms, for example, producing retardation of regenerative growth, delayed molting, reduction in burrowing activity and deformities in limbs in the fiddler crab (Weis and Perlmutter 1987; Weis et al. 1987; Weis and Kim 1988), impairment of egg production in the calanoid copepod (Johansen and Mohlenberg 1987), reduction in larval growth in the silverside (Hall et al. 1988) and avoidance reactions in the Baltic amphipod (Laughlin et al. 1984). Recently, a relationship between metabolic capacity, accumulation and toxicity of BTs in marine organisms has been reported in terms of comparisons of BT residue levels in organisms at various trophic levels in the food chain (Fent 1996; Takahashi et al. 1999; Ohji et al. 2002a). The results indicate that though BTs accumulated in most organisms at levels up to 70,000 times higher than those in seawater, no significant biomagnification was observed in the higher levels of the food chain (Takahashi et al. 1999). High concentrations have, however, been found in lower trophic animals such as caprellids. It seems that TBT accumulates specifically for the caprellids in the marine ecosystem regardless of the trophic level in the food chain, and it can be a break point for the disturbance in the natural food chain structure. It is considered causing them to accumulate BTs at elevated concentrations because of their lower metabolic capacity to degrade TBT (Ohji et al. 2002a). The BTs seem to be accumulated in a species specific manner. Thus, studying the implications of species-specific accumulation and the biological effects of BTs on caprellids may provide some clues to understanding the accumulation mechanisms in the coastal ecosystem as well as the mode of action of BTs in organisms. © 2009 Springer Japan.