Biological monitoring of occupational exposure to di(2-ethylhexyl) phthalate (DEHP) in two cases: the French flexible-PVC industry and the use of vinyl gloves

DEHP is a phthalate plasticizer of PVC, classified as a Category 1B reproductive toxicant (EU). Soft PVC are very often plasticized with 40% (w/w) phthalates. As DEHP is weakly bound, the risk of contamination and cutaneous penetration should be considered.These two studies provide in risk assessment, additional occupational exposure data, which are particularly scarce.


OBJECTIVE
Assess the occupational exposure to DEHP in flexible PVC-industry (1) and in workers using vinyl gloves by the quantification of DEHP metabolites.
METHOD
Over 5 days of pre- and post shift sampling, five urinary metabolites of DEHP, mono (2-ethylhexyl) phthalate (MEHP), mono (5-carboxy-2-ethylpentyl) phthalate (5Cx-MEPP), mono(2-ethyl-5-oxohexyl) phthalate (5oxo-MEHP), mono(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP) and 2-ethylhexanoïc (2-EHA), were quantified in 62 workers and 29 controls from six PVC factories and 50 users of vinyl gloves, gloves contained 45% by weight of DEHP, 16 controls.

RESULTS

· In flexible-PVC industry, there was a significant increase (Mann-Whitney U test, P < 0.05) of post-shift excretion in the exposed workers versus the controls and in the post-shift versus pre-shift concentrations only in the exposed workers. Median of internal dose (ID) calculated for exposed workers was < 10µg/kg bw/day, but 43 workers have ID > 20µg/ kg bw/day, Rfd from EPA, USA, 5 workers > 50µg/kg bw/day, TDI from EFSA (EU).
· In the workers using vinyl gloves, there was a significant increase of post-shift excretion in the workers using vinyl gloves versus the controls. No significant increase in the post-shift versus pre-shift excretions. Analysis of variance (Anova) did not demonstrate a significant influence with the duration of the use and the numbers of pairs used. Median of ID (4.4 µg/kg bw/day) was close the ID obtained from EU Risk Assessement (6.7 and 9.3 µg/kg bw/day).

CONCLUSION

A low level of exposure of DEHP related to the use of vinyl gloves might be considered. In the flexible-PVC industry, there is a clear evidence of occupational exposure of workers in studied factories. An epidemiological survey is needed to complete the DEHP risk assessment.