Study On Residue And Exposure Of 4-hydroxybenzoic Acid Esters In Pharmaceuticals And Urine

With the development of modern economic and technology, various chemicals are applied to our daily life. P-hydroxy benzoic acid esters(parabens) are widely applied to food, personal care products and pharmaceuticals as a kind of preservative with excellent performance. Due to the expended applications and field, the frequency of contact and expose to them are increased. Animal experiments proved that parabens had the estrogen activity, it may affect the development of human reproductive system, and causing breast cancers for females. Therefore, the study on the residue status in environment and human exposure of parabens are necessary.In this study, the residue levels of parabens in 109 urine samples(68 males and 41 females) and 100 pharmaceutical samples were analyzed. Urine samples and pharmaceutical samples were treated by solid phase extraction and liquid liquid extraction, respectively. Then parabens were analyzed using HPLC-MS/MS and UPLC-MS/MS. For the urine samples, the detection rate for all parabens was 100% and the concentrations ranged from 0.82 to 728 ng/m L(median 14.3 ng/m L). Me P and Pr P were the dominated compounds. The concentrations of parabens in females urine samples were two times higher than males. However, the differences between different regions were not significant. For the pharmaceutical samples, parabens were detected in 97% samples, the total concentrations were from 0.90 to 1256 ng/g(median 119 ng/g). The composition characteristics of parabens with pharmaceuticals were similar to urine. According to the reported concentrations with Chinese food, personal care products and dust, the exposure doses of Chinese young adults were comprehensively studied. Personal care products were the main exposure way of external exposure, especially for women(28.0 μg/kg-bw/day), contributing to 68.6% to total internal expsoure. According to the urine concentration, the exposure levels of Chinese young adults were 18.4 μg/kg-bw/day and 40.8 μg/kg-bw/day for males and females, respectively. The results of risk assessment to parabens indicated that the human health risk level was low.The urine exposure dose can be used as internal exposure, while other esposure doses were cosidered as external exposure. A comprehensive comparasion between external exposure and internal exposure were made in this study. The results indicated that the external exposure and internal exposure couldn’t match well, especially for males, whose external exposure only accounted for 20.9% of the internal exposure. Because women use a large number of personal care products, their external exposure accounted for about 71.3% of their internal exposure. The results indicated that there maybe some unknown external exposure ways are not considered, or the expsoure assessment methods exist some errors, especially for the parameters. Based on the resutls of this study, it is necessary to carry out some deep research on the relationship between the internal exposure and external exposure in the future for more accurate assessment of the human health risk to parabens.