| Whereas inorganic tin species such as Sn(II) chloride, oxide or sulphate do not seem to be toxic or cancerogenic, organotin species are highly toxic. Of all organic tin species the tri-aryl compounds are most dangerous. TBT is mainly used in antifouling paints, wood preserving fungicides, desinfectants and molluscicides, whereas TBT plays a role in agriculture, (e.g. fungicides), other organotin species (e.g. dialkyl compounds) are used as stabiliser for PVC, industrial catalysts or precursors for SnO2-films or glass. The production worldwide of organotin compounds was some 35 000 tons in 1980 of which 8 000 tons were triorganotin compounds for biocidal use; 3 000 tons were produced for antifouling paints, 1 000 tons for wood preservatives, 3 000 tons for agrochemicals and 1 000 tons for disinfectants. Especially the application of TBT in antifouling paints has caused concern. Ship hulls with a TBT containing paint will not be covered under water by mussels and sea weed and therefore allow faster sailing. Also fishing nets have been treated with TBT. However, the TBT leached from the paint by water acts as a strong poison to larvae of oysters, mussels and fish. Therefore France and the UK have already legislation on the use of TBT in ship paints, Ireland announced in April 1987 that legislation on the use of organotins as antifouling agents would be banned. The objective of the project is essentially to develop, through collaborative work of expert laboratories, the methodology to obtain accurate results in the determination of the most important organic tin compounds. It is also intended to certify sediment and mussel samples. |
