Biocidal products used for spray application against the oak processionary moth (OPM) require authorisation in accordance with Regulation (EU) No. 528/2012 of the European Parliament for that use. For authorisation, a risk assessment based on exposure estimation is performed for all intended uses of the respective product.

Detailed information on the application process and the resulting exposure of operators and of bystanders was lacking until now. It is expected that the main routes of exposure are dermal and inhalation. Spray applications carried out for control of OPM show significant differences to plant protection applications, thus assessing exposure from OPM control on the basis of plant protection models would bear a high level of uncertainty.

This study investigated the potential dermal and inhalation exposure of pest control operators during spray application against the OPM. Moreover, the potential exposure of bystanders was quantified. Task-specific exposure data for hand-held as well as vehicle mounted sprayers were collected during OPM control with a diflubenzuron-containing insecticide in 2014 and 2015.

The data collected within the field studies were grouped and evaluated with regard to the type of spray application and working task, covering also tasks such as weighing out and portioning of the biocidal product, on-site preparation and application of the spray liquid and cleaning of the equipment. The valid data obtained form a reliable database for the authorisation of biocidal products according to the EU-Regulation.