Aggregate consumer exposure to UV filter ethylhexyl methoxycinnamate via personal care products

- Aggregate exposure levels are reported for UV filter ethylhexyl methoxycinnamate.
- A probabilistic exposure assessment was conducted for Swiss− German consumers.
- A Monte Carlo method was performed at an individual consumer level.
- Children were the highest exposed individuals in our study population.
- Sunscreen is a key contributor to internal aggregate exposure.

Ultraviolet (UV) filters are substances designed to protect our skin from UV-induced damage and can be found in many categories of personal care products (PCPs). The potential endocrine-disrupting effects attributed to UV filter ethylhexyl methoxycinnamate (EHMC) are being debated. We evaluated the aggregate exposure of the Swiss-German population (N = 1196; ages ≤ 1-97 years) to EHMC via the use of PCPs; thus we provide the first comprehensive information about the current EHMC exposure sources and aggregate exposure levels. In our probabilistic modeling method performed at an individual level, PCP use data obtained by a postal questionnaire were linked to concentration data on EHMC gained from chemical analyses of PCPs used by the questionnaire respondents. The modeled median and 99.9th percentile of the internal aggregate exposure for the general population were 0.012 and 0.873 mg day− 1 kg− 1 and 0.008 and 0.122 mg day− 1 kg− 1 for the summer/autumn and winter/spring period, respectively. The major contributors to internal aggregate exposure were sunscreen products in summer/autumn (females: 64%; males: 85%; children aged ≤ 12 years 93%). In winter/spring, lip care dominated for females (30%) and sunscreen for males (38%) and children aged ≤ 12 years (50%). Overall, the internal aggregate exposure estimates for the studied population are shown to be below the Derived No Effect Level (DNEL) for EHMC i.e., the level of exposure above which humans should not be exposed; however, when an intense short-term exposure via sunscreen is accounted for during a sunbathing day, at the high-end percentiles (99.9th) the predicted aggregate exposure exceeds the DNEL for thyroid-disrupting effects such as for children aged ≤ 4 years, who might be particularly susceptible to endocrine disrupting events. It is nevertheless critical to acknowledge that quantitative data on transdermal penetration of EHMC from PCPs are currently insufficient. Since long-term effects of endocrine disruptors are not known, future studies are warranted to provide accurate quantitative data on transdermal penetration of EHMC and to determine its metabolic fate in humans.