Urinary levels of bisphenol A, triclosan and 4-nonylphenol in a general Belgian population.

Bisphenol A, triclosan and 4-nonylphenol are among the endocrine disruptors which are widely used in daily products. In this study, we reported total urinary levels of bisphenol A, triclosan and 4-nonylphenol, in order to evaluate the baseline contamination of a general population in Belgium. Bisphenol A and triclosan were detected in respectively 97.7% and 74.6% of the samples examined demonstrating that the general Belgian population is extensively exposed to both chemicals. On the other hand, 4-nonylphenol was not detected in any urine samples analyzed, suggesting either low exposure, inadequate biomarker, or that urine is an inappropriate biological matrix for assessing exposure to nonylphenol commercial mixtures. Geometric mean concentration was determined for bisphenol A at 2.55 μg/l and for triclosan at 2.70 μg/l. No significant difference was observed between levels and gender for both bisphenol A and triclosan. When classified by age, the 20-39 year group showed the highest triclosan levels, while all age groups seemed to be similarly exposed to bisphenol A. Both bisphenol A and triclosan urinary levels were not correlated with creatinine excretion in our healthy population, questioning the relevance of the creatinine adjustment in reporting these chemical levels. Bisphenol A levels in urine of people living in the same home and collected on the same time were fairly correlated, confirming the assumption that dietary intake would be the primary route of exposure. Triclosan urinary levels were not correlated with bisphenol A levels.