Pesticides in rivers, lakes and groundwater in Europe

Pesticides were assessed against effect or quality thresholds between 2013 and 2021. One or more pesticides were detected above their effect threshold at 10% to 25% of all surface water monitoring sites. Exceedances were often caused by the insecticide imidacloprid, and the herbicide metolachlor. Exceedances of one or more pesticides were detected at between 4% and 11% of groundwater monitoring sites, mainly by atrazine and its metabolites and bentazone. Differences in weather, crop type and reporting mean that changes between years may not be significant.

Percentage of reported monitoring sites with pesticides exceeding thresholds in a) surface waters and b) groundwater in Europe, weighted by country area

Pesticides can contaminate surface waters and groundwater and if their concentrations are above critical thresholds, they can be harmful to the environment.

The European Green Deal sets targets to reduce the use of and risks from chemical pesticides by 50% by 2030 in the Zero Pollution Action Plan, Farm to Fork and Biodiversity strategies, with a focus on protecting ecosystems and improving biodiversity.

The Water Framework Directive (WFD) sets environmental quality standards for pesticides in surface water. To assess the chemical status of groundwater, a precautionary quality standard of 0.1µg/L is set for pesticides according to the Groundwater Directive, reflecting the desire to keep pesticide concentrations in groundwater at low levels.

Figure 1 shows that in 10% to 25% of all surface water monitoring sites, one or more pesticides were detected above the effect threshold each year between 2013 and 2021. Exceedances of one or more pesticides were detected at between 4% and 11% of groundwater monitoring sites.

Pesticides most often causing exceedance in surface waters are the insecticide imidacloprid and the herbicide metolachlor, some of which were no longer approved for use in plant protection products during the monitoring period. The proportion of monitoring sites with exceedances has decreased by more than half from 2020 to 2021 (Figure 1). Reporting from large countries with few monitoring sites, with fewer exceedances in 2021, may explain part of this decrease owing to weighting by country surface area.

In groundwater, the herbicide atrazine and its metabolites as well as bentazone caused most exceedances. Atrazine was not approved for use in plant protection products during the monitoring period. Despite restrictions on atrazine since 2007, it continues to be found in groundwater because it is very persistent. Bentazone is currently approved until May 2025 and is under review to determine if approval can be renewed.

Losses from the application of pesticides may vary considerably between years, depending upon, for example, crop type and the weather, while the frequency of monitoring of pesticides in surface waters can be limited to one year out of three. In addition, characteristics of the monitoring campaigns (e.g. number of samples taken annually, number of pesticides monitored, number of monitoring sites) may vary from year to year. Changes to the approval status of pesticides influence their use and presence in water, which can also lead to difficulties in interpreting trends over time. For these reasons, changes between years may not be significant.

Percentage of reported monitoring sites with pesticides exceeding thresholds in surface waters, different sized rivers, lakes and groundwater in European countries, 2016-2021

Figure 2 focuses on the more recent, shorter period between 2016 and 2021, where pesticides were reported from a total of 9,505 monitoring sites for surface waters and 13,328 sites for groundwater. The number of sites with data reported for surface waters varies by country from less than 10 (Hungary, Iceland, Luxembourg, Romania, Sweden, Switzerland) to more than 1,000 sites (France, Italy, Spain). There is similar variation in groundwater monitoring sites: numbers range from 33 in Lithuania to over 3,000 sites in Italy (with over 1,000 in Austria, France, Germany, Spain).

The number of pesticides reported in surface waters ranges from fewer than ten substances (Austria, Iceland, Romania, Switzerland) to more than 100 substances (Belgium, Czechia, Finland, France, Germany, Italy, Netherlands, Spain). For groundwater, the lowest number of pesticides monitored was reported from Austria (6) and the highest number from France (242).

Exceedance rates of more than 30% were reported in 8 out of 30 countries for surface waters and in none of 21 countries for groundwater.

Supporting information

DefinitionMethodologyPolicy/environmental relevance

Policy context and targets

Context

The Water Framework Directive (WFD) and its daughter directives on environmental quality standards in water policy, as amended in 2013, and quality standards for groundwater set quality objectives and targets for pesticides in surface waters and groundwater and should protect water quality from pesticide pollution.

According to the WFD, pesticide concentrations above critical threshold levels lead to surface waters failing to achieve ‘good chemical status’, based on pesticides listed as priority substances, and ‘good ecological status’, based on pesticides listed as river basin-specific pollutants. The WFD also lists pesticides that are groundwater pollutants to assess the chemical status of groundwaters. For each pesticide, a quality standard of 0.1µg/L was set in the Groundwater Directive, which is not a health-based, but a general precautionary limit value.

Failure to achieve effect thresholds and quality standards in water means failure to achieve the environmental objectives of the WFD.

The European Green Deal and its associated strategies and actions — the Zero Pollution Action Plan, Farm to Fork Strategy, Biodiversity Strategy and Chemicals Strategy for Sustainability — brings renewed ambition to significantly reduce the use of and risk from pesticides and improve the risk assessment of chemicals.

EU policies aimed at reducing the potential risk from pesticides are also supported by the Plant Protection Products Regulation, the Sustainable Use of Pesticides Directive and the Biocidal Products Regulation.

The Plant Protection Products Regulation sets out rules for the authorisation of plant protection products and their marketing, use and control. Based on this regulation, the Seventh Environment Action Programme set the objective that, by 2020, the use of plant protection products should not have any harmful effects on human health, or unacceptable influence on the environment, and that such products should be used sustainably.
The Sustainable Use of Pesticides Directive aims to reduce the risks and impacts of pesticide use on human health and the environment and to promote the use of integrated pest management and alternatives such as non-chemical approaches.
The Biocidal Products Regulation focuses on the marketing and use of biocidal products.

Accuracy and uncertainties

Effect threshold data (i.e. EQS for surface waters and 0.1µg/L for groundwaters)

In surface waters, ecotoxicologically-based effect thresholds were determined to assess exceedance rates at monitoring sites. The exceedance of these thresholds indicates pollution by pesticides at levels potentially affecting aquatic ecosystems. The lowest ecotoxicologically-based effect threshold is used as a conservative scenario. The EQS have not necessarily been defined in every country according to the same criteria as those used here, which makes a comparison of national assessments with this indicator difficult. For surface waters, effect thresholds could be identified for only 49% of the pesticides reported; 51% of all pesticides reported could not be considered in the assessment, so that the actual risk of pesticides in surface waters is likely to be underestimated.

In groundwater, exceedances were assessed against the 0.1µg/L quality standard set out in the Groundwater Directive. No regulated quality standards for non-relevant metabolites are available and so they were excluded from the assessment.

The indicator demonstrates a need to harmonise limit values (including nationally set river basin-specific pollutant EQS values).

Measured environmental data (i.e. monitoring data reported under WISE SoE WISE-6)

The differences in the underlying data (e.g., number of samples taken annually, sampling methodology, number of pesticides, number of monitoring sites) between years and countries must be taken into account for direct comparisons. The calculation method used to determine exceedance rates with country weightings attempts to take into account the imbalance of the data in terms of spatial, temporal and pesticide coverage. However, a minimum number of monitoring sites, monitored pesticides and sampling time points, should be reported to achieve a representative overview of pesticide concentrations in European waters.

With regard to the general methodological approach of the present indicator calculation, the "one-out-all-out" principle applied does not reflect the magnitude of the threshold exceedance or the potentially greater impact due to the simultaneous presence of several pesticides at a monitoring site.

Data sources and providers

Metadata

DPSIRTopicsTagsTemporal coverageGeographic coverage

TypologyUN SDGsUnit of measure

The indicator is expressed as percentages of monitoring sites where one or more pesticides exceed the effect threshold for surface waters or the quality standard for groundwater.

To reduce the impact of uneven spatial and temporal data reporting, a country area weighting factor was used for Figure 1:

∑ Share of monitoring sites with exceedances per country (%) × country area (km²) /

∑ Area of countries with reported monitoring sites per year (km²)

The country weighting factor was not used for Figure 2 in the indicator.

Frequency of dissemination

References and footnotes

Pesticides include both active substances from plant protection products and biocides as well as their relevant metabolites.
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The insecticide imidacloprid was approved for use in plant production products until December 2020.
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In Waterbase Water Quality, results of metolachlor and S-metachlor are combined. The herbicide metolachlor was not approved during the monitoring period, S-metalochlor was approved until January 2024.
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Atrazine was not approved for use in plant protection products during the monitoring period.
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Bentazone is currently approved until May 2025 and is under review to determine if approval can be renewed.
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EU, 2008, Directive 2008/105/EC of the European Parliament and of the Council of 16 December 2008 on environmental quality standards in the field of water policy, amending and subsequently repealing Council Directives 82/176/EEC, 83/513/EEC, 84/156/EEC, 84/491/EEC, 86/280/EEC and amending Directive 2000/60/EC of the European Parliament and of the Council, OJ L 348, 24.12.2008, p. 84-97.

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EU, 2013, Directive 2013/39/EU of the European Parliament and of the Council of 12 August 2013 amending Directives 2000/60/EC and 2008/105/EC as regards priority substances in the field of water policy, OJ L 226, 24.8.2013, p. 1–17.

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EU, 2009, 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 and repealing Council Directives 79/117/EEC and 91/414/EEC, OJ L 309, 24.11.2009, p. 1-50.

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EU, 2009, Directive 2009/128/EC of the European Parliament and of the Council of 21 October 2009 establishing a framework for Community action to achieve the sustainable use of pesticides, OJ L 309, 24.11.2009, p. 71-86.

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EU, 2012, Regulation (EU) No 528/2012 of the European Parliament and of the Council of 22 May 2012 concerning the making available on the market and use of biocidal products, OJ L 167, 27.6.2012, p. 1-123.

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EU, 2013, Decision No 1386/2013/EU of the European Parliament and of the Council of 20 November 2013 on a General Union Environment Action Programme to 2020 ‘Living well, within the limits of our planet’, OJ L 354, 28.12.2013, p. 171-200.

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Pesticides in rivers, lakes and groundwater in Europe

Figure 1. Percentage of reported monitoring sites with pesticides exceeding thresholds in a) surface waters and b) groundwater in Europe, weighted by country area

Figure 2. Percentage of reported monitoring sites with pesticides exceeding thresholds in surface waters, different sized rivers, lakes and groundwater in European countries, 2016-2021

Supporting information

Policy context and targets

Context

Metadata

References and footnotes