Knowledge on the exposure part of the risk assessment is equally important as knowledge on the toxicological endpoints, but this knowledge is scarce. In exposure assessment, attention for a sensitive subpopulation such as for example children is important.
A child’s exposure pattern to a chemical in a consumer product can be very different from that of an adult. Exposure assessment for children requires consideration of child-specific behaviours and activities when defining exposure scenarios. RIVM developed guidance for child-specific exposure assessments for non-food consumer products (Van Engelen et al., 2007).
OECD Children’s exposure decision tree
In 2019, the OECD’s Working Party on Exposure Assessment (WPEA) developed a children’s exposure decision tree. This should enhance awareness for the inclusion of children’s exposure in risk assessments, specifically in a product safety assessment or substance risk assessment. The decision tree facilitates risk assessors in determining whether a separate assessment for children is necessary.
Hand-to-mouth contact is a child specific behaviour that can lead to a relevant exposure for children. RIVM has proposed new default values for assessing the degree of exposure of children to chemicals following hand-to-mouth contact (Ter Burg et al., 2007).
The OECD is also working on this subject, in July 2019 a study of Health Canada has been published in which RIVM has contributed with several case studies. The case studies lead to a list of good practices with respect to risk assessment of chemical substances in articles via hand mouth contact in children.
Chemical substances in toys
Another important source of exposure for children is chemical substances in toys, for which RIVM has developed a special risk-based methodology at the request of DG-Enterprise of the European Commission (Van Engelen et al., 2008). Default values for estimation of exposure using the ConsExpo model can be found in the Children’s toys Fact sheet developed in 2002. In 2020 work has started to update this fact sheet (see ConsExpo for more information).
Topical RIVM studies
Examples of RIVM studies in which exposure scenarios of children have been relevant are the evaluation of health risks of playing sports on synthetic turf pitches with rubber granulate (2017), the assessment of the product limit for PAHs in rubber articles: the case of shock-absorbing tiles (2016) and the study on risk assessment on phthalates in toys (RIVM for NVWA 2016).