Alternatives Assessments for Hazardous Chemicals in Children's Consumer Products: Can Predictive Toxicology Tools Help?

Abstract

Exposure to toxic chemicals in consumer products can have lasting impacts on children’s health due to their increased vulnerability during sensitive periods of development. Regulation and reporting requirements have increased demand for safer alternatives. This project examines how predictive toxicology tools can fill data gaps in alternatives assessments for hazardous chemicals found in children’s consumer products. Data available from European Chemical Agency’s (ECHA) Endocrine Disruptor Substances of Concern classification was compared with predictive toxicology tools that rely on in silico and in vitro data: the toxicological prioritization index (ToxPi), calculated based on information in the US EPA’s ToxCast Database; and exposure rankings developed in the high throughput exposure screening program., ExpoCast. Three chemical groups were considered: phthalates, parabens and bisphenols. Only one out of the 24 alternative chemicals had data available through ECHA, yet in vitro data from ToxCast was available for 83% of alternative chemicals and animal in vivo data from the Comptox Chemistry Dashboard was available for 66% of alternative chemicals. The No Observable Adverse Effects Levels derived from the in vivo studies were higher for alternative than conventional chemicals, suggesting the alternatives may be less toxic. ToxPi scores, however, showed little difference between conventional and alternative chemicals. ExpoCast rankings were available for 20 of the 24 alternative chemicals. The rankings indicated that conventional chemicals have higher predicted exposure than alternatives. The results from this case study suggest that predictive toxicology tools can help fill data gaps when existing classifications are incomplete. This project is supported by the US EPA (FP-91779601-0, RD 83573801, RD 83451401) and the US NIEHS (5P01ES009601). The views expressed in this paper are those of the authors and do not necessarily reflect the views of the US EPA.