Toluene-2,6-diisocyanate (2,6-TDI), toluene-2,4-diisocyanate (2,4-TDI), and toluene diisocyanate mixed isomers are the three forms of TDI commonly used in commerce. Acute exposure to TDIs can result in severe skin, eye, lung, and throat irritation. TDIs are possible carcinogens and may be teratogens (reproductive hazards). Workplaces are the primary source of exposure to TDIs, which are intermediary chemicals in the manufacture of polyurethanes. In Massachusetts, businesses used 7.4 million pounds of TDIs in 1998.
There is limited evidence that 2,4-TDI may be a reproductive hazard; it has caused temporary impotence in males. It is a mutagen, causing genetic changes.
In 1998, Massachusetts. facilities used 7.4 million pounds of TDIs. The major end-uses for TDI in Massachusetts are polyurethane foam (79%), surface coatings (5%), spandex (11%), and adhesives and sealants (4%). TDI use increased by 42% between 1990 and 1998.