Exposure assessment of phthalates in French pregnant women using reverse dosimetry and biomonitoring data from the Elfe pilot study
Résumé
Phthalates are a family of chemicals that can be found in a wide array of consumer products, including food packaging, medications, cosmetics, perfumes, building materials, paints, adhesives, children's toys and medical equipments made with polyvinyl chloride (PVC) plastics (Berman et al., 2009). Phthalates are not chemically bound to the products such as PVC and can thus easily be released into the environment by direct release, migration, evaporation, leaching and abrasion of and from the products they are used in. The ubiquitous use of phthalate esters results in widespread general population exposure. Numerous studies focused on exposure to phthalates because several epidemiological studies have suggested adverse effects that were similar to reproductive toxicities observed in experimental animal. Some phthalates such as DnBP, DiBP, BBzP DiNP and DEHP are known as being reproductive and developmental toxicants in animals. This study reports urinary concentration measurements of phthalate metabolites for French pregnant women. Several phthalates metabolites of short-chain phthalates, DEP (MEP), DnBP (MnBP), DiBP (MiBP), BBzP (MBBzP), and long-chain phthalates, DEHP (5OH-MEHP, 5oxo-MEHP, 5cx-MEHP, 2cx-MEHP, MEHP), DiNP (MiNP, 7oxo-Summe-MeOP, 7OH-MeOP, 7cx-MeOP), DnOP( MnOP, MCPP,), DCHP (MCHP) were measured. The measured concentrations were compared to those obtained in other European or American biomonitoring studies on pregnant women and highlighted high levels of DEHP metabolites. Toxicokinetic modelling (Lorber et al., 2010), integrating all the different metabolites measured, was used in a reverse dosimetry approach to estimate the exposure to DEHP. It allowed to back calculate a mean daily intake of exposure to DEHP of 4.2 µg/kg BW/d. In addition, this modelling pointed out that MEHP concentration was significantly higher than expected whereas other metabolites concentrations were well described. This could have been due to a contamination of the samples or indicated a very recent exposure probably at the hospital (Vandentorren et al., 2011). Significant differences of MEHP urinary concentration were observed in function of the type of delivery suggesting rather a very recent exposure probably due to perfusion materials than a contamination.