Biomonitoring of glycol ethers exposure in a sample of the general population of North of France: influence of occupational and personal factors

Introduction
Glycol ethers enter the composition of numerous industrial and consumer products, cosmetics or medicines. Reproductive and developmental effects justified restrictive measures for some of them. Limitation of ethylenic series and development of propylenic series in the past decades changed the exposure levels of occupational and general populations. Exposure assessment is important for the identification of at risk sectors and for planning of priority actions. Alkoxyacetic acids metabolites are good exposure indicators of glycol ethers.

Methods
The present study analysed 8 urinary metabolites of glycol ethers (methoxyacetic=MAA, ethoxyacetic=EAA, 2-methoxypropionic=MPA, propoxyacetic=PAA, butoxyacetic=BAA, phenoxyacetic=PhAA, 2,2-methoxyethoxyacetic=MEAA, and 2,2 ethoxyethoxyacetic=EEAA acids) on urinary samples of 120 volunteers from the working age general population of the North of France (20-59 years old), recruited in the Regional Health Examination Centers. Personal and professional data were collected by questionnaire.

Results
Each metabolite was detectable on at least 98% of the samples, except for MPA (70%). Quantification could be performed for PhAA on 85% of the samples, MAA on 55%, EEAA on 45%, BAA on 12%, EAA and MEAA on less than 5%. Percentile 95 and maximum values were respectively 0.13 and 0.22 mg/l for MAAU, 17.54 and 80.0 mg/l for PhAAU, 1.0 and 5.2 mg/l for EEAAU, 0.1 and 1.3 mg/l for BAAU, < LDQ (limit of quantification) and 0.15 mg/l for EAAU, < LDQ and 0.21 mg/l for MEAAU. Links were put in evidence between reported exposure to painting and solvents and BAA, to painting and MAA, to solvents and EEAA and to cosmetics (body creams) and PhAA.

Discussion
This descriptive study brings information on the frequency of detection and the exposure levels of the general population to the main glycol ethers. The evaluation of the background level is indeed useful to interpret the concentrations observed on exposed populations either during occupation, or during specific environmental situations or poisonings.