Table of contents
3. Further comments
1) Here is space for additional comments reviewers may wish to make.
Should you have comments on:
- the approach to normalising the data;
- non-relevant metabolites for groundwater;
- the use of RACs for threshold exceedances in surface waters;
- further sources for EQS values;
please use the sections below.
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The above mentioned "pesticides together" could be a first step to take into account mixtures.
2) Approach to normalisation - use of country area weighting
Fig 1 uses country area weighting as a way to normalise the reported data. Country area weighting has some disadvantages (principally that if a country with a large area has a high exceedance rate in one year, that can influence the overall result) but this approach seems to be a reasonable way to normalise the results and be less prone to fluctuations owing to variability in numbers of reported data. We expect some noise in the data as the WISE 6 reporting adapts to this new indicator, but that this will settle down in a few years to provide a more consistent trend.
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The normalization of the exceedance rate to the country area makes sense, as it is about environmental protection and each square kilometer of EU territory should get the same weight for an EU-wide assessment of water body quality.
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Comment from Germany, Federal State Saxonia:
The methodology introduces a weighting based on area proportions in order to reduce the effects of heterogeneous spatial and temporal data. This is intended to compensate for the temporal and spatial imbalances in the data of the individual countries. The formula proposed for this results in an indicator which relates the sum of the percentage shares of the exceedances to the land areas of the participating countries and the sum of the areas of these countries per year. Whether this approach actually brings an advantage in terms of compensating for data gaps is difficult to assess and certainly also depends on the type of data gaps. We would like to point out that the participating countries have very different percentages of agricultural land and percentages of arable land and permanent crops in the respective land area, in addition to the different density of measuring points and gaps in the data. Arable land and permanent crops represent the area category from which the emissions of pesticides usually originate. Since the measuring points mainly detect immissions emanating from arable land and permanent crops, a reference to this appears more conclusive than to the total area of the federal states.
3) Exclusion of non-relevant metabolites from groundwater indicator assessment
We excluded non-relevant metabolites (nrM) from the calculation of exceedance rates in groundwater. This is in line with the 2006 Groundwater Directive, where the quality standard for pesticides of 0.1µg/l does not apply to nrM.
However, recent work towards a Europe-wide study recommends inclusion of nrM in Annex I of the Groundwater Directive, with the need to establish harmonised definition and assessment of nrM and to set quality standards in line with quality standards of Groundwater Directive.
Should nrM be included in the indicator? If so, what quality standards should apply?
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There is a wide variety between countries in identifying nrM. Not all countries apply the same assessment methods for identifying nrM.
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- Last paragraph: As mentioned in paragraph one, there currently is no EU-wide quality standard established for nrMs in groundwater. This may or may not change in the current process of Annex I/II revision of the EU Groundwater Directive. Some MSs have defined threshold values for nrMs in drinking water (e.g., Germany, Austria, The Netherlands), but for general surface or groundwater this was not the case yet. Therefore, we propose to exclude nrMs from the current exceedance value calculation.
- In case an EU-harmonized limit value for nrMs in drinking or groundwater is needed, we propose to use the TTC-based threshold value of 9 µg/L for all nrMs (Cramer Class III substances, default WHO methodology for drinking water guidance values – 20% allocation of ADI to drinking water; see also Laabs, V., Leake, C., Botham, P., and Melching-Kollmuß, S. 2015. Regulation of non-relevant metabolites of plant protection products in drinking and groundwater in the EU: Current status and way forward. Regul. Toxicol. Pharmacol. 73, 276-286).
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Comment from UBA Germany, Unit Pesticides:
We suggest to consider non relevant metabolites of pesticides with a threshold value of 1 µg/L. As emerging contaminants, non relevant metabolites shall be considered for precautionary reasons: Many of them are very mobile and persistent, difficult to analyse, hardly removable from water resources and with a scarce data base compared to active substances. In some cases, non relevant metabolites were classified as relevant later on or showed unexpected effects (e.g. transformation to carcinogenic compounds during water treatment, Schmidt and Brauch (2008): <a href="https://pubmed.ncbi.nlm.nih.gov/18800499/" rel="nofollow">https://pubmed.ncbi.nlm.nih.gov/18800499/</a>). Also, the awareness for non relevant metabolites is rising in many member states. For instance, the new drinking water directive demands the member states to define a guide value for non relevant metabolites. Implications for other directives and national law are expected. In Germany, a threshold value in groundwater regulation was discussed and supported by various stakeholders (but finally not implemented, however at least monitoring duties were established in the same law).
Indeed, there is no legislative threshold or limit value yet. However, in plant protection regulation the value of 10 µg/L according to SANCO 221/2000 guidance (<a href="https://ec.europa.eu/food/system/files/2016-10/pesticides_ppp_app-proc_guide_fate_metabolites-groundwtr.pdf" rel="nofollow">https://ec.europa.eu/food/system/files/2016-10/pesticides_ppp_app-proc_guide_fate_metabolites-groundwtr.pdf</a>) is applied for the groundwater risk assessment of pesticides on EU level and, in some member states, as exclusion criteria for the authorization of plant protection products. It is basically common sense that concentrations above 10 µg/L for non relevant metabolites in groundwater are not acceptable. However, a threshold of 10 µg/L is not sufficient for the analysis of trends and the precautionary consideration of risk mitigation measures: Leaching to groundwater underlies high retardation in soil and there is hardly any further degradation in the groundwater bodies. Therefore, elevated concentrations cannot or only slowly may be reduced by measures or reduced application. Based on the established German concept of Health Related Indication Values (HRIV) UBA suggests to use the value of 1 µg/L. This value is also very close to the threshold of 0.75 µg/L as trigger for deeper assessment according to SANCO 221/2000. This value is also applied by some EU member states for their authorization of plant protection products, e.g. Denmark and Italy.
Considering these trends and discussions it would be adequate to proactively include non relevant metabolites in the pesticide indicator.
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Comment from German Federal State Schleswig-Holstein (repeated from 1. Key Messages):
The indicator concept was tested with a dataset derived from the WFD monitoring of the German Federal State Schleswig-Holstein. The results were:
- Groundwater: We acknowledge, that the indicator does not use “Non relevant Metabolites” since there is no agreed EU threshold. In Germany these metabolites are assessed with “Health Related Indication Values (HRIV)“ specialized for each metabolite. Exceedances of these threshold values for the non-relevant metabolites are the main causes of the poor status in the group of plant protection and degradation products.
4) Possible use of Regulatory Acceptable Concentrations (RAC) as effects threshold for pesticides in surface waters
Exceedances in surface waters were calculated using EU-wide or nationally-regulated thresholds (Environmental Quality Standards – EQS). We could not find EQS for about a third of the pesticides reported to WISE-6, which means these substances could not be included in the assessment of threshold exceedance.
Under Regulation 1107/2009 (PPP Regulation), RACs are required for pesticides to prevent harm to aquatic organisms. We investigated the possibility of using RACs as an alternative threshold to EQS, as all pesticides should have RAC values. However, we found that RACs and EQS could not be used interchangeably, as they consider different protection goals, apply to different spatial scales and are based on different valuation methods.
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I find this argument a bit weak, especially the one on the spatial scale. While this is conceptually true, the practice is that most EQS and all tier-1 RAC are derived from a laboratory ecotoxicological endpoint (the lowest available) divided by an assessment factor. Hence, the consideration of the spatial scale is not really impactful.
I find also a bit odd that tier-1 RAC were considered too different compared to EQS, but the use of maximum acceptable detection limits from the watchlist – something whose relation with toxicity is not so straightforward – was considered OK as ‘an indicator of the likely order of magnitude’.
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A direct alignment of the RAC and the EQS for a particular pesticide (or metabolite) is not expected, as they consider different protection goals and apply to different types of water bodies.
Nevertheless, the comprehensive ecotoxicological data produced for pesticide authorization purposes under Regulation 1107/2009 can be and is used to derive robust EQS values according to the respective European Commission Common Implementation Strategy Guidance (EC 2018).
We therefore propose to derive “missing” EQS values based on the available ecotoxicological data compiled under Regulation 1107/2009 according to WFD CIS guidance in a transparent and participative way (EU-level process led e.g., by EEA), including EU registration holders of pesticides as stakeholders in this process. -
Download attached file
Comment from UBA Germany, Unit Pesticides:
For 34 pesticides we have compared the highest-tier Regulatory Acceptable Concentration (RAC) used in our monitoring of small streams in the agricultural landscape in Germany with the MAC-EQS values used for the pesticide indicator (with the addition of some own MAC-EQS derivations). The result was: RAC values could be used for the assessment of short term peaks, if no MAC-EQS is available (see attached file displaying RAC/MAC ratios). In contrast, a relatively high discrepancy exists between the RAC and AA-EQS values for the same compound, since the various RAC-values are based on either acute, chronic or even mesocosm data with respective assessment factors (AF) and hence, were often much higher than AA-EQS that are based on chronic data only.
Comment to the Dashboard - for countries to check their reporting
If possible, add the option to select "Pesticides together", which would correspond to the data presented in the indicator under Figure 2.