TBTO – a hazardous pollutant

The World Health Organisation (WHO) International Programme on Chemical Safety has reviewed the human and environmental exposure to tributyltin oxide (TBTO) a biocidal preservative for wood, cotton textiles, paper and paints and stains for residential homes. It is also added as an anti-fouling agent in numerous formulations of marine paints. 
    TBTO is moderately-to-highly acutely toxic to laboratory mammals in short-term studies. In numerous studies, both short-term and long-term, the critical effect of TBTO is immunotoxicity. 
Tributyltin compounds are extremely hazardous to some aquatic organisms because of their toxicity at very low concentrations in water. 
    TBTO is an endocrine disrupter. Its concentration in some coastal waters is above levels which cause such adverse effects as reproductive failure and population decline. The lowest reported effect concentrations for tributyltin are 2.4-4.8 ng/litre for induction of shell deformities in Pacific Oyster and imposex (the development of male characteristics by a female) in dogwelk. The effects on farmed fish indicate that paints containing tributyltin should not be used on restraining nets.

Tributyltin oxide, WHO IPCS, No. 14, 1211 Geneva 27, Switzerland, Sw. Fr. 16, 1999, 29pp.

[This article first appeared in Pesticides News No. 46, December 1999, page 21]