Speciation of organotins in poly(vinyl chloride) products

Extraction studies on butyl- and octyltins were conducted with three poly(vinyl chloride) (PVC) product types: clear food container, rigid pipe and flexible membrane. Three solvents, tetrahydrofuran, xylene and methylene chloride were evaluated for extraction efficiency. Methylene chloride extracted more than 97% of the total extractable organotin in two extractions and resulted in the highest recoveries of analytes from all three PVC products. Method detection limits ranged from 0.3 to 0.9 microgram alkyltin/g PVC. The mean precision of the method is 6.8% relative standard deviation. Food industry PVC product samples contained between < 0.8 and 8751 micrograms/g octyltins and < 0.3 and 4.7 micrograms/g butyltins. Butyltins (< 0.9-5985 micrograms/g) were detected in potable water pipe samples. Pipe used in industrial applications contained both butyl- (13-1501 micrograms/g) and octyltins (701-3033 micrograms/g).