Biological monitoring of exposure to toluene diisocyanate

Biological monitoring of exposure to 1,5–naphthalene diisocyanate and 4,4’-methylenediphenyl diisocyanate

“…Hence, we concluded that making any adjustments would only add another source of uncertainty and used the non-adjusted urinary levels in the evaluations. This is in congruence with a similar study of TDI exposed workers (Sennbro et al 2004b). Both our results and a previous study by Kääriä et al (2001) indicate a poor correlation between airborne exposure to MDI and urinary biomarker levels.…”

Eye and airway symptoms in low occupational exposure to toluene diisocyanate

“…Personal airborne exposure was measured during one shift for 79 of the exposed workers examined (and, in addition, for another 15 exposed workers from other shifts) with single glass-fiber filters impregnated with 2-methoxyphenyl piperazine (14)(15)). An analysis of the isocyanates was performed by liquid chromatography combined with tandem mass spectrometry as described by Östin et al (16).…”

“…An analysis of the isocyanates was performed by liquid chromatography combined with tandem mass spectrometry as described by Östin et al (16). The personal 8-hour time-weighted average levels ranged from below the limit of quantification to 2.6 ppb for 2,4-TDI and from 0.01 to 3.6 ppb for 2,6-TDI (12,15). For the remaining 57 workers participating in the medical examinations, the full-day personal exposures were estimated from a combination of department, task, and results obtained with the air measurements.…”

“…Plasma samples were collected on the day of the health examination, which took place within 2 weeks of the day of the air sampling. The collection of the biological samples has been described in detail by Sennbro et al (17). For the workers who had given two urinary samples, the sample collected on the day of the health examination was used in the statistical analyses.…”

Biomarkers of exposure in Monday morning urine samples as a long-term measure of exposure to aromatic diisocyanates

“…Methods for biological monitoring, based on hydrolysis of urine or plasma and analysis of the corresponding amine, have been used since the mid eighties (Rosenberg and Savolainen 1986). High correlations between air levels of diisocyanates and levels of the corresponding diamines as biomarkers in hydrolysed urine have been shown both experimentally and in work environment for toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI) (Maitre et al1993;Tinnerberg et al 1995;Maitre et al 1996;Kääriä et al 2001a;Liu et al 2004;Sennbro et al 2004). However, for 4,4´-methylenediphenyl diisocyanate (4,4´-MDI) and 1,5-naphtalene diisocyanate (1,5-NDI) low or no correlations have been seen between air levels and urinary biomarkers (Kääria et al 2001b;Sennbro et al 2006) indicating either another uptake or another metabolism.…”