Objectives-To develop a method for the measurement of a maetabolite of hexa
methylene diisocyanate (HDI), an isocyanate, and use it to assess the expos
ure of sprayers employed in motor vehicle repair shops.
Methods-Urine samples were taken from sprayers wearing personal protective
equipment and spraying in booths or with local exhaust ventilation, from by
standers, and from unexposed subjects. Samples were analysed for a metaboli
te of HDI, hexamethylene diamine (HDA), by gas chromatogaphy-mass spectrome
try (GC-MS).
Results-HDA was detected in four sprayers and one bystander out of 22 worke
rs. No NDA was detected in the urine of unexposed subjects.
Conclusions-Exposure to isocyanates still occurs despite the use of persona
l protective equipment and the use of a booth or extracted space. Health su
rveillance is likely to be required to provide feedback an the adequacy of
controls even if such precautions are used and to identify eases of early a
sthma. Biological monitoring can provide a useful additional tool to assess
exposure and the adequacy of controls in this group of exposed workers.