Systematic evidence map (SEM) for ethylbenzene: An overview of the evidence base informing developmental, reproductive, and nervous system (DART-NTX) effects
Ethylbenzene is naturally occurring in in crude petroleum and used in commercial products for industrial and consumer use, including paints, solvents, and pesticides. Exposure to ethylbenzene is widespread and can occur via ingestion or inhalation of contaminated air, water, and soil. The EPA IRIS program is developing an updated IRIS assessment for ethylbenzene. The results of a systematic evidence map (SEM) are presented, focusing on studies describing potential reproductive, developmental, and nervous system (DART-NTX) effects.
A comprehensive literature search was conducted to identify all studies available as of January 2022. A Population, Exposures, Comparators, and Outcomes (PECO) statement was developed to guide literature screening to identify data informing potential human health effects of ethylbenzene exposure, including oral and inhalation routes. All studies meeting PECO are included in the SEM, which provides a high-level summary of study design and results.
A total of 112 studies (52 human; 60 animal) meeting PECO were identified, with 63 (20 human; 43 animal) reporting DART-NTX relevant outcomes. DART effects were reported in 34 studies (8 human; 26 animal) evaluating various outcomes, including fertility and pregnancy outcomes, offspring growth/morphology, and developmental milestones. The majority of available NTX-related studies (13 human; 30 animal) evaluated adults and focused on decreased auditory function. Limited data are available to inform potential neurodevelopmental effects, which may be an important data gap for this chemical. The views expressed are those of the authors and do not necessarily represent the views or the policies of the U.S. EPA.