04 June 2019

How to objectify exposure of the population to spray from phytopharmaceutical products in Wallonia

To what extent are local residents exposed to spray from phytopharmaceutical products (PPP)? What measures can be proposed to limit this exposure? These are the questions that the PROPULPPP study seeks to answer.

How to objectify exposure of the population to spray from phytopharmaceutical products in Wallonia

When applied to an agricultural plot, some PPPs can be carried in the air (drift) to reach neighbouring sites in varying quantities depending on the weather conditions and the techniques of application. Volatile PPPs can be carried away relatively far while PPPs associated with solid particles or liquids (aerosols) settle in the nearby vicinity, on the soil surface or on objects. There is little data on actual exposure of neighbouring residents to these drifting PPPs.


The PROPULPPP study’s objective is to measure the drift of PPPs near agricultural plots, to determine the risks of cutaneous and inhalation exposure by neighbouring residents using a predictive model and finally to assess the effectiveness of actions aimed at limiting the exposure of these populations to the PPPs.


Wind tunnel and on-site tests with sprayed tracers were conducted to determine the maximum wind speed when spraying and to reducing the drifting of PPPs by using antidrift nozzles. In addition, measures for dispersion of PPPs were conducted under actual conditions between March and September 2018, in the vicinity of experimental plots, in schools and at resident’s homes to check the effectiveness of recommendations aiming to reduce the risks of local resident’s exposure, such as the minimum distance between the field and residents, exposure of a hedge or the time for spraying during the day.


The results of PROPULPPP confirm the usefulness of the measure taken in the Decree of the Walloon Government on June 14, 2018, aimed at better protection for the populations bordering agricultural plots. However, these measures should be refined and supplemented. In addition, creating a monitoring tool at the edge of the field and in agricultural localities would make it possible to check compliance with recommendations and to identify, if necessary, additional prevention measures.


PROPULPPP is coordinated by the ISSEP in partnership with the CRA-W and the University of Liège Gembloux Agro-Bio Tech. The CRA-W is mainly involved in management of experimental plots, in-depth analysis of sediment drift and analysis of PPP residues on sensors. The CRA-W also provides expertise in the use and authorisation of phytopharmaceutical products.


Project financed by the SPW/DGO3

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