Assessment of non-dietary, human exposure to pesticides.

Assessment of non-dietary, human exposure to pesticides is an integral part of pesticide authorisation at the EU level. In this thesis, models were used to predict exposure of vulnerable human sub-populations to pesticides and thus to assess risks to health. Two high-quality pesticide usage datasets previously collected by Fera Science Ltd. and for EFSA were analysed. Trends in pesticide usage and major drivers of exposure and thus risk were identified, including any implications for regulatory procedures over the period investigated. Residential exposure of pregnant women living at 100 and 1000 m downwind of treated orchards indicated improving fate (vapour pressure) and hazard profiles (reproductive/developmental toxicities) of pesticides applied in England and Wales over a 25- year period (1987, 1996, 2004 and 2012). Overall, results reflected the influence of changing policies during the 1990s and the ongoing review programme at national level. Assessment of 50 agricultural professional operators across five cropping systems in Greece, Lithuania and the UK indicated a range of applications with potential for risk. Estimated exposure was significantly influenced by variations in agricultural practices and working behaviours involving the use of personal protective measures, including the extensive use of wettable powder formulations in Greece and large areas of land treated per day in Lithuania and the UK. The 50 selected professional operators handled a range of active substances and/or coformulants with known/possible endocrine disrupting activity during single spray days. At maximum, one operator handled five such active substances and ten such co-formulants in a single day. Thus, higher risk is expected in mixture than that predicted for single active substances. Although the use of models in risk assessment has inherent uncertainties, these results add to the existing body of knowledge and allow a holistic assessment of the pesticide regulatory procedures over the period investigated.