Review of air concentrations of pesticides for estimating exposure to vapour in European risk assessments

In current European non-dietary risk assessment for bystanders and residents, one of the plant protection product exposure pathways to be addressed is vapour inhalation. At present, active ingredients are grouped according to vapour pressure and assigned corresponding values. Risk assessments are driven by only two default air concentration values. Sampling is inconsistent, background data are sparse and many factors having an impact on air concentrations are not considered. Within the changing regulatory landscape over the last 20 years, criteria for volatility grouping and consequently for vapour exposure estimation have been applied heterogeneously.