Introduction

Organotin chemicals are those compounds containing at least one bond between tin and carbon. This paper presents a brief overview of some of the major commercial organotin chemicals, their applications and substitutes, as well as the environmental pressures coming to bear on these products. As the world of organotin chemicals is quite extensive and diverse, this paper will briefly discuss some of the major commercial uses concentrating on the alkyltins (methyltins, butyltins, octyltins), with a brief mention of phenyltins and cyclohexyltins used in certain applications such as ecig products. The majority of organotin uses are comprised of five major commercial applications: PVC Heat Stabilizers, Biocides, Catalysts, Agrichemicals, and Glass Coatings. These uses account for approximately 20K tons of tin consumption per year.

There has been a great deal of public attention focused on the toxicological and ecotoxicological aspects of organotins recently. There is special concern over the use of tributyltin (TBT) because of its biocidal properties. However, clear distinctions must be drawn between the triorganotin compounds (which have three tin-carbon bonds) used as biocides and pesticides, and the mono- and diorganotin compounds, which have one and two tin-carbon bonds respectively, used in stabilizer, catalyst, and glass coating applications. The latter exhibit no biocidal properties in contrast to the TBT compounds. Certain mono- and dialkyltins have been approved as PVC stabilizers for food contact throughout the world. It is highly inappropriate to generalize that all organotin chemicals have similar toxicological and environmental properties, yet this is happening more frequently. One of the goals of Product Stewardship is to help customers, regulators, and stakeholders in general to understand the distinctions.

For complete text of this paper in *.PDF format, please see "The World of Organotin Chemicals"