Aggregate exposure approaches for parabens in personal care products: a case assessment for children between 0 and 3 years old
Open Access
- 26 June 2013
- journal article
- Published by Springer Science and Business Media LLC in Journal of Exposure Science & Environmental Epidemiology
- Vol. 24 (2), 208-214
- https://doi.org/10.1038/jes.2013.33
Abstract
In the risk assessment of chemical substances, aggregation of exposure to a substance from different sources via different pathways is not common practice. Focusing the exposure assessment on a substance from a single source can lead to a significant underestimation of the risk. To gain more insight on how to perform an aggregate exposure assessment, we applied a deterministic (tier 1) and a person-oriented probabilistic approach (tier 2) for exposure to the four most common parabens through personal care products in children between 0 and 3 years old. Following a deterministic approach, a worst-case exposure estimate is calculated for methyl-, ethyl-, propyl- and butylparaben. As an illustration for risk assessment, Margins of Exposure (MoE) are calculated. These are 991 and 4966 for methyl- and ethylparaben, and 8 and 10 for propyl- and butylparaben, respectively. In tier 2, more detailed information on product use has been obtained from a small survey on product use of consumers. A probabilistic exposure assessment is performed to estimate the variability and uncertainty of exposure in a population. Results show that the internal exposure for each paraben is below the level determined in tier 1. However, for propyl- and butylparaben, the percentile of the population with an exposure probability above the assumed “safe” MoE of 100, is 13% and 7%, respectively. In conclusion, a tier 1 approach can be performed using simple equations and default point estimates, and serves as a starting point for exposure and risk assessment. If refinement is warranted, the more data demanding person-oriented probabilistic approach should be used. This probabilistic approach results in a more realistic exposure estimate, including the uncertainty, and allows determining the main drivers of exposure. Furthermore, it allows to estimate the percentage of the population for which the exposure is likely to be above a specific value.Keywords
This publication has 22 references indexed in Scilit:
- Risk assessment of combined exposure to multiple chemicals: A WHO/IPCS frameworkRegulatory Toxicology and Pharmacology, 2011
- Possible endocrine disrupting effects of parabens and their metabolitesReproductive Toxicology, 2010
- The mismeasure of dermal absorptionJournal of Exposure Science & Environmental Epidemiology, 2010
- Potential estrogenic effect(s) of parabens at the prepubertal stage of a postnatal female rat modelReproductive Toxicology, 2010
- Lack of effect of butylparaben and methylparaben on the reproductive system in male ratsBirth Defects Research Part B: Developmental and Reproductive Toxicology, 2008
- Final Amended Report on the Safety Assessment of Methylparaben, Ethylparaben, Propylparaben, Isopropylparaben, Butylparaben, Isobutylparaben, and Benzylparaben as used in Cosmetic ProductsInternational Journal of Toxicology, 2008
- Hydrolysis of a series of parabens by skin microsomes and cytosol from human and minipigs and in whole skin in short-term cultureToxicology and Applied Pharmacology, 2007
- Modeling mixtures resulting from concurrent exposures to multiple sourcesToxicology and Applied Pharmacology, 2007
- Systemic Uptake of Diethyl Phthalate, Dibutyl Phthalate, and Butyl Paraben Following Whole-Body Topical Application and Reproductive and Thyroid Hormone Levels in HumansEnvironmental Science & Technology, 2007
- The Effect of Occlusion on Epidermal Penetration of Parabens from a Commercial Allergy Test Ointment, Acetone and Ethanol VehiclesJournal of Investigative Dermatology, 2000