Exploratory report Tin and tin compounds

Abstract

In the Netherlands tin is produced from concentrate and secondary production (about 3,500 tonnes Sn per year), whereas about 5,000 tonnes Sn per year is applied. Of this amount about 4,200 tonnes is applied as inorganic tin (most for the manufacturing of tin plate) and about 800 tonnes Sn is applied as organotin compounds (most in pesticides, PVC-stabilizer and anti-fouling paints). Available information indicates that the risk of inorganic tin compounds to humans is very small, if present at all. The risks of inorganic tin compounds to aquatic ecosystems are considered to be small and are likely to be restricted to surface waters in the vicinity of industrial sites. Although little information on exposure to and effects of inorganic tin in soil organisms, current and future emissions to soil indicate a low priority to fill in these gaps in knowledge. As to organotin compounds it is assumed that environmental concentrations unlikely present a risk to the general population. The risk of organotin compounds in food to humans is unknown, mainly because no quantitative data on exposure are available. Triphenyl and tributyl organotin compounds present a risk to aquatic ecosystems in the Netherlands. Information on the toxicity to sediment and soil organisms as well as on the occurrence in soil are lacking, hampering a sound risk evaluation. It is recommended [a] to determine the concentrations of organotins in food, [b] to execute the ban on triphenyl tin acetate and triphenyl hydroxide as soon as possible and [c] to stimulate alternative methods for anti-fouling paints. Further it is advocated to initiate a study into the degradation rates of organotins in sediment and soil in order to determine the maximum allowable emission per year.<br>