The "cocktail effect” of pesticide residues

Current status of cumulative risk assessment and implications for analysis

Feb 2026. Food often contains several pesticide residues at the same time. This results in a “cocktail effect” that reflects real-world exposure. In order to scientifically capture these additive effects, the EU is therefore continuously developing the methodology of cumulative risk assessment (CRA). The resulting assessments are expected to be fully integrated into regulation by 2030.

We provide you with an overview of the current status of EU and EFSA work on the assessment of cumulative and possible synergistic risks from multiple pesticide residues in food. We also explain how we can support you in complying with legal requirements with professional pesticide analysis.

Cumulative and synergistic effects of pesticide residues in the EU spotlight

Annual reports from the European Food Safety Authority (EFSA) and national monitoring programmes have shown for years that a significant proportion of the food samples tested contain multiple pesticides at the same time. Real dietary exposure is therefore multiple exposure resulting from the use of several pesticides. In order to assess this situation scientifically, the EU is continuously working on further developing the methodology of cumulative risk assessment (CRA), based on the evaluation of cumulative effects^[1].

Regulation (EC) No. 396/2005 on maximum residue levels of pesticides in or on food and feed, and Regulation (EC) No. 1107/2009 concerning the placing of plant protection products on the market, explicitly stipulate that cumulative and synergistic effects must be considered as soon as reliable methods are availableRegulation (EC) No. 396/2005 on maximum residue levels of pesticides in or on food and feed, and Regulation (EC) No. 1107/2009 concerning the placing of plant protection products on the market, explicitly stipulate that cumulative and synergistic effects must be considered as soon as reliable methods are available^[2,3].

Scientific background on synergistic and cumulative effects

Synergisms occur when different active substances mutually reinforce each other, producing a stronger combined effect than the sum of their individual effects. Ecotoxicological studies have documented these effects in combinations involving cypermethrin and the fungicides azoxystrobin or prochloraz. These combinations have been shown to influence soil organisms and ecological processes. The results are ecologically relevant and demonstrate the potential for enhanced mixture effects^[4].

Pesticides that affect the same toxicological endpoint can have a cumulative, i.e. additive, effect. The EFSA groups such substances into Cumulative Assessment Groups (CAGs) to enable joint effects to be scientifically assessed^[5].

EFSA specifies groups for reproductive effects (CAGs)

Since 2025, EFSA has been identifying key biological functions in men and women that can be impaired by certain pesticides. These include sexuality, fertility, and pregnancy, among others.

This specification creates a clearer structure for assessing active substances with comparable reproductive toxic effects together in future. This is an important step forward, particularly in cases involving multiple residues in food, as it enables cumulative risks to reproduction to be assessed more reliably^[7].

Mixture Assessment Factor (MAF)

Some organisations have pointed out that cumulative risk assessment (CRA) has not yet been fully implemented in the EU. Due to the almost unlimited possibilities for combining active substances, it is virtually impossible to comprehensively assess the risks of mixtures from a scientific perspective. Against this background, the introduction of a Mixture Assessment Factor (MAF) has been proposed as a complementary safety measure. This is intended to mitigate potential combination effects in regulation until the CRA methodology is fully implemented in 2030^[8].

Farm to Fork Strategy and EU reduction targets

The EU's Farm to Fork Strategy is part of the Green Deal. It aims to reduce the use and risk of chemical pesticides by 50% by 2030. At the same time, integrated pest management (IPM) is to be applied more consistently. While the Farm to Fork Strategy aims to reduce risks at source, the CRA methodology provides the scientific basis for a more realistic assessment of the health impact of multiple residues.

Your expert laboratory partner for pesticide analysis

With our combined LC MS/MS and GC MS/MS multi-method screening, we cover over 800 pesticides and metabolites for you analytically. This enables you to identify multiple residues and prepare for potential future requirements regarding EFSA CAGs.

We are happy to support you at any time with the analysis of your products for pesticides and provide advice on your individual questions. For further information or individual support, please contact your personal account manager or our expert Ayman Farhod Naeem directly.

References:

[1] FoodSafety4EU - EFSA (2024). Protecting public health: understanding the importance of cumulative risk assessment of pesticides
[2] Regulation (EC) No 396/2005 of the European Parliament and of the Council of 23 February 2005 on maximum residue levels of pesticides in or on food and feed of plant and animal origin (consolidated text)
[3] Regulation (EC) No 1107/2009 of the European Parliament and of the Council of 21 October 2009 concerning the placing of plant protection products on the market (consolidated text)
[4] Beyond Pesticides (2025). Study of Biological Diversity Effects of Pesticide Mixtures Highlights Underestimated Risks to Ecosystems
[5] European Commission (accessed online on 11 Feb 2026). Cumulative Risk Assessment - State of play on the assessment of risks caused by the presence of multiple pesticide residues in food
[6] European Commission (2021). EFSA-SANTE Action Plan on Cumulative Risk Assessment for pesticides residues
[7] EFSA (2025). Specific effects on the reproductive function including fertility relevant for cumulative risk assessment of pesticide residues
[8] Pesticide Action Network Europe (2021). Towards the implementation of a Mixture Assessment Factor (MAF): PAN Europe’s Position Paper