Biological monitoring of TDI-derived amines in polyurethane foam production.
BACKGROUND
Toluene diisocyanate (TDI) is used in industry in the production of flexible polyurethane foam, commonly a mixture of the 2,4- and 2,6- isomers. The production process may lead to exposure to diisocyanates which are associated with respiratory disease. A method has been available for the determination of TDI biomarkers in urine for some years.


OBJECTIVE
To explore the usefulness of urinary toluenediamine (uTDA) in assessing whether dermal absorption of diisocyanates makes a significant contribution to a worker's total exposure.


METHODS
Twenty-six workers took part in the study. Thirteen workers whose duties brought them into physical contact with uncured polyurethane foam during their shift (handlers) were compared to a control group of 13 workers in the same block plant environment had no physical contact with uncured foam on the day that sampling took place (non-handlers). Creatinine-adjusted uTDA levels in the two groups were compared across a work shift.


RESULTS
Both groups of workers were exposed to similar levels of airborne TDI. Ten handlers were found to have TDA in post-shift urine samples above detection limits compared with two non-handlers (P < 0.05). No clear relationship was found between the level of airborne TDI exposure and post-shift uTDA.


CONCLUSIONS
uTDA provides a useful indication of the contribution which skin absorption makes to total TDI exposure. The results suggest that skin protection when handling uncured polyurethane foam may not receive sufficient consideration.
Austin
Shaun
S
Mediscreen, Pennine Acute Hospitals NHS Trust, Trust Headquarters, Westhulme Avenue, Oldham OL1 2PN, UK. shaunaust@aol.com
D000328:Adult; D015415:Biomarkers / Q000652:urine; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000032:analysis*; D010655:Phenylenediamines / Q000652:urine*; D011140:Polyurethanes; D012869:Skin Absorption
D015415:Biomarkers; D010655:Phenylenediamines; D011140:Polyurethanes; C028279:polyurethane foam; C025235:2,6-diaminotoluene; C010914:2,4-diaminotoluene