Pesticide emissions into the air: understanding, quantification, prediction - A literature review, through the lens of the agricultural practices

The contamination of the air by pesticides and its effects on health and on environment are issues of growing concern. A number of discussion groups, projects or workshops were recently setting up about this issue, including the pesticide registration with the report of the FOCUS Air Group in 20081. In France, the 3rd national environmental health plan (Plan National Santé Environnement, PNSE 32), released by the French Ministry of Ecology in December 2014, includes a measurement campaign of pesticides concentrations in the air. The scientific literature in the field is relatively large, mainly concerning different air transport pathways during and after application (drift, post-application volatilization, atmospheric dispersion of volatilized compounds, deposition). However, the available results are very scattered and often controversial due to the high variability of pesticides properties and also the diversity of pesticide use conditions, depending on crops, agronomic practices and environmental conditions. In addition, the actors involved in this topic such as research institutes, air-quality monitoring agencies, state services, are various and the state of knowledge is very variable depending on the process under consideration. For these actors, the availability of pesticide emission factors has to be analyzed because they can be very useful to quantify sources, assess their impact on air quality using models and the exposure of the population via inhalation, allowing the prioritization of mitigation actions. In this context, there is a strong need to summarize all these studies and to update the state of knowledge about the emissions of pesticides into the air including all transfer pathways in relation with the application conditions. A literature review is under way to meet this need; this synthesis will be viewed through the lens of the French agricultural practices, which can be representative of the practices of the Southern EU area during pesticide zonal evaluation. This work aims at (1) synthetizing an up to date state of knowledge about emission (existing models e.g. emission models or Life Cycle Assessment (LCA) models as well as existing datasets) and then (2)identifying existing pesticide emission factors or methods to calculate them based on models,(3)evaluating their relevance in the French context (practices including spraying system, crop systems, properties of the pesticides used), (3) drawing avenues for their improvement and development and (4) identifying the possible levers of actions to reduce transfer to the atmosphere. Finally, this work must allow a methodology for pesticide emissions inventory in France, transferable to other countries with similar agronomic practices