Exposure to Preservatives in Personal Care Products: Case Study Comparing Biomonitoring Data to Model Predictions

摘要

Exposure models are critical to the evaluation of the safety of personal care product ingredients. However, very few studies are available comparing model predictions to exposure data. Data from a recent intensive observational biomonitoring study of eight volunteers using personal care products were used to estimate minimum and maximum absorbed doses of three parabens (methyl-, ethyl-, and n-propyl [MP, EP, and PP]) and triclosan over four days of recorded use of toothpaste, shampoo, shower gel, shaving cream, face cream, and sunscreen with the target preservative ingredients. Four available models were run in default mode assuming 0.1% ingredient concentration to estimate average daily absorbed doses for each ingredient and participant based on the participant-specific combination of product uses: ConsExpo, run in deterministic mode; the European Commission Scientific Committee on Consumer Safety (SCCS) risk assessment screening model algorithms; SHEDS-HT; and Creme Care & Cosmetics (Creme CC). Minimum estimated absorbed doses across volunteers based on biomonitoring data ranged from 0.2 to 12.1 ug/kg-d for MP, 0.05 to 2.4 ug/kg-d for EP, 0.02 to 5.0 ug/kg-d for PP, and 0.02 to 26.9 ug/kg-d for triclosan. With a few exceptions, the results of the exposure models fell within a factor of 10 of the biomonitoring data depending on the chemical modeled. ConsExpo and SCCS point estimates were often the most conservative, but often fell within the range of minimum to maximum estimated exposure levels. The Creme CC and SHEDS-HT distributions of exposure estimates often encompassed the estimated exposure levels based on biomonitoring data. Specific patterns of under- and over- estimation of actual exposures will be presented, including comparison of estimated and measured product use amounts and frequencies. A sensitivity analysis on the assumed concentration of preservatives in the products and other factors will also be presented.