They are mainly used in producing polyurethane foam, polyurethane elastomers, polyurethane adhesives and polyurethane varnish. The industrial manufacture of polyurethane or any processing of polyurethane products involving heating can cause exposure to isocyanates. The production and use of isocyanates has been increasing for many years. In Western Europe, polyurethane production increased from 994,000 tons in 1983 to 1,687,000 tons in 1992 and this increase has continued. It is difficult to estimate the number of people whose health is at risk in their workplaces because of isocyanates, but they can be counted by the thousand.
Strict regulations apply to the use of isocyanates as such.
The problem is that the methods so far used to measure exposure have failed to reveal the true extent of the problem. The methods used for many years to measure isocyanates have turned out to be inadequate, untrustworthy and inaccurate. The limitations of the principal methods have meant that symptoms have not been linked to exposure to isocyanates. New measurement methods make it possible to study the decomposition products of polyurethanes. Other constituents of technical isocyanate products can also be determined.