Tributyltin oxide (TBTO) is an organotin compound chiefly used as a biocide (fungicide and molluscicide), especially a wood preservative. Its chemical formula is [(C4H9)3Sn]2O. It has the form of a colorless to pale yellow liquid that is only slightly soluble in water (20 ppm) but highly soluble in organic solvents. It is a potent skin irritant.
Based on sediment resuspension estimates, the most prominent toxin dispersed would be tributyltin, a once common, now banned chemical used as a biocide agent in the paint of ship hulls to prevent damage from aquatic organisms.