Cumulative risks from combined exposure to multiple pesticide residues in fruit and vegetables

Summary

Cumulative intake of mixtures of pesticide residues through consumption of fruits and vegetables can lead to health risks that are not controlled under the current EU system using only the maximum residue limit (MRL) and acute reference dose (ARfD) for single substances on single food products. In a collaboration between the European Commission, the European Food Safety Authority and member states, methods have been developed to implement Regulation (EC) No 1107/2009 that states that plant protection products should not have harmful health effects, also taking into account possible cumulative and synergistic effects. These methods have been implemented in the Monte Carlo Risk Assessment (MCRA) software which is available for national and European public institutions to perform pesticides mixture risk assessment. This report describes a web portal that was developed to allow cumulative risk assessment by the Dutch private vegetable and fruit sector organised in the Foundation Food Compass using MCRA with the monitoring data collected in the Food Compass database. A case study was performed to combine Food Compass monitoring data from the years 2013-2020 with consumption data of children from the Dutch national food consumption survey. The main interest was to assess the risk of cumulative exposure due to the combined intake of multiple pesticide residues in their diet. If potential risks were observed, it was of interest to know which residues and foods contributed to such risks and if there were trends over the period of the monitoring. The results of the cumulative assessments were compared to an analysis of limit value exceedances at the level of single measurement results. The results presented in this report are provisional due to insufficient availability of data. Some of the analytical scopes in the Food Compass database could not be linked appropriately to the active substance groups used for cumulative risk assessment. Food processing steps, such as peeling or juicing of citrus fruits, are expected to reduce residue levels, but the collection of processing factors to account for this in the calculations was incomplete. Limit values are sometimes changed, and recently artificially low limit values were introduced in the sectoral system to generate alerts for substances which have been classified as genotoxic. Such data will then also have an artificial impact on the cumulative assessments. The conventional analysis of single residue measurements showed that 1-3% of residue levels exceeded the MRL throughout the period 2013-2020. However, the frequency of conservatively estimated exceedances of the ARfD using the PRIMo 3.1 model decreased from around 3% to below 1% in the same period. It was also found that ARfD exceedances did often occur without an associated MRL exceedance. The cumulative assessments indicated that the probability of a critical acute exposure was estimated to be in the range 0.1- 0.4% during the period 2013-2019 (the results for 2020 were affected by an artificial low ARfD value and are therefore not useful to estimate real risk). Nevertheless, the main identified risk drivers were occurrences of chlorpyrifos and chlorpyrifos-methyl in some citrus fruit products such as juices for which no account of processing effects was included in the assessment due to lack of validated data. Including validated processing factors for citrus fruit products as they are consumed in practice will result in more realistic critical probabilities which are expected to be lower. It is planned to update the current trend analysis in further work.