Isocyanates are asthmagens and most studies of occupational exposures to isocyanates have concentrated on inhalation of the vapor or aerosol. However, exposure may also occur through skin contact with the aerosol or during the handling of liquid isocyanates. Prolonged contact may lead to irritation or contact dermatitis.
Isocyanates are not produced in the United Kingdom (UK). UK industry, however, currently imports between 90000 and 100000 tonnes of isocyanate per year. Isocyanates are widely used in the UK for the manufacture of flexible and rigid foams, fibers, coatings such as paints and varnishes, and elastomers. The UK industry occupational population potentially exposed to isocyanates is about 25000 workers and the overall use of isocyanates by UK industry is increasing slowly.
Traditionally, the occupational group considered to be most at risk from isocyanate induced occupational asthma is spray painters in the motor vehicle repair industry. Because of this, HSE has undertaken campaigns, targeted specifically at the motor vehicle repair industry, to identify how, why and for how long workers are exposed to isocyanates. The findings are discussed in this paper.
The distribution of cases of occupational asthma throughout UK industry by occupation and agent as reported to two UK occupational health databases over the last ten years are also discussed in this paper. Findings are then compared against industry's own occupational health data and sector population breakdowns. Consideration is also given to whether an underlying UK trend of increasing non- occupational asthmas could also influence the reporting of work-related cases.