Occurrence of Organotin Compounds in the Canadian Aquatic Environment Five Years after the Regulation of Antifouling Uses of Tributyltin

Abstract

A survey was conducted of water and sediment from across Canada in 1993-94 to assess the effectiveness of the 1989 regulation of antifouling uses of tributyltin (TBT) under the Canadian Pest Control Products Act. The survey was also designed to assess concentrations of 13 other organotin species in water and sediment, and in sewage treatment plant influents, effluents and sludges. The main conclusion is that the 1989 regulation has only been partially effective. It has had some effect in the reduction of TBT concentrations in fresh water, but not in sea water. It has had less effect in the reduction of TBT concentrations in sediment, probably because of the longer persistence of TBT in sediment than in water. In many locations the TBT concentration was high enough to cause acute and chronic toxicity to aquatic and benthic organisms. In some areas there may be potential for recycling TBT from contaminated sediments back into the water column. In addition, it appears that large harbours that handle ships legally painted with TBT-containing antifouling paints continued to experience ecotoxicologically significant TBT contamination. Other organotin species found appear to pose no acute or chronic hazards to fresh water or marine organisms, but nothing is known of their hazards to benthic organisms. The presence of monooctyltin and dioctyltin in sediments and sewage treatment plant influents, effluents and sludges is reported for the first time, and tripropyltin is quantified in sediments for the first time.

Ecotoxicological effects at contaminated sites

“…Due to the extreme toxicity and the ecotoxicological hazards associated with TBT in antifouling paints (Fent and Meier, 1992;Horiguchi et al, 1997) restrictions on its use have been implemented in many countries in the mid to end 1980's. As a consequence, TBT concentrations in harbor waters decreased significantly at many locations in industrialized countries (Chau et al, 1997;Fent and Hunn, 1995), but this is not or less the case in other locations (Biselli et al, 2000;Takahashi et al, 1999), in developing countries (Kannan et al, 1995) or in marine mammals Kannan et al, 1997;Tanabe, 1999). In spite of regulations, the release of TBT into aquatic ecosystems persists due to its use in antifouling paints on large vessels, paint removal from pleasure boats, application of TBT in wood preservation, and remobilization from contaminated sediments (Fig.…”

Butyltin Compounds in River Otters (Lutra canadensis) from the Northwestern United States

“…Water concentrations of butyltins (BTs ϭ MBT ϩ DBT ϩ TBT) decreased in most locations subsequent to the regulations (Valkirs et al 1991;Fent 1996). However, in certain locations, TBT concentrations in water exceeded the guidelines or were cause for concern even after several years of being banned (Dowson et al 1992;Ritsema 1994;Fent and Hunn 1995;Chau et al 1997). Further, many researchers have noted little or no reduction in TBT concentrations in sediments several years after regulations were enacted (Quevauviller et al 1994;Dowson et al 1994;Fent and Hunn 1995;Fent 1996).…”

“…Further, many researchers have noted little or no reduction in TBT concentrations in sediments several years after regulations were enacted (Quevauviller et al 1994;Dowson et al 1994;Fent and Hunn 1995;Fent 1996). Similarly, no apparent decline in TBT concentrations have been observed in large harbors that handle ships legally painted with TBT-containing antifouling paints (Fent 1996;Chau et al 1997). Because of its continued use on large ships and apparent persistence in sediment, TBT is still a concern in near-shore urban waterways (Meador 1997).…”

Validation, using a chemometric approach, of gas chromatography–inductively coupled plasma–atomic emission spectrometry (GC–ICP–AES) for organotin determination

“…Because of their numerous uses in a wide range of industrial, agricultural and domestic activities, the organotins are continuously released into the environment [1,2,3,4].…”