Biological monitoring of exposure to di(2-ethylhexyl) phthalate in six French factories: a field study.

The aim of this study was to assess, by biological monitoring, workers' exposure to di(2-ethylhexyl) phthalate (DEHP) in the flexible-PVC industry in France to provide additional occupational exposure data, which are particularly scarce. Over 5 days of pre-and post-shift sampling, three urinary metabolites of DEHP, mono (2-ethylhexyl) phthalate (MEHP), mono (5-carboxy-2-ethylpentyl) phthalate (5cx-MEPP) and 2-ethylhexanoic acid (2-EHA) were quantified in 62 workers and 29 controls from six factories. Analyses were performed by high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) after on-line extraction. Median concentrations of the pre- and post-shift urinary samples in the exposed workers were 12.6 and 28.7 μg/l for MEHP, 38.6 and 84.4 μg/l for 5cx-MEPP and 20.4 and 70.6 μg/l for 2-EHA, respectively. In the controls, the corresponding values were 4.8 and 4.7 μg/l for MEHP, 15.1 and 12.4 μg/l for 5cx-MEPP and 21.8 and 20.5 μg/l for 2-EHA, respectively. There was a significant increase (Mann-Whitney U-test, P < 0.05) of post-shift excretion in the exposed workers versus the unexposed controls and in the post-shift versus pre-shift concentrations only in the exposed workers. Values of 250 and 500 μg/l (100 and 280 μ/g creatinine) for MEHP and 5cx-MEPP, respectively, are proposed as guidance values. There is clear evidence of occupational exposure of workers in these factories. The guideline values proposed should prevent high exposures in the soft PVC industry, particularly in factories where DEHP compounds or plastisols are employed. An epidemiological survey is needed to complete the DEHP risk assessment.