Summary Emission Reduction Plan (ERP) for flufenacet

In Belgium, flufenacet has been encountered in surface water in concentrations that exceed the environmental quality standards (EQS). Therefore, 7 authorization holders (Adama Registrations B.V., Albaugh TKI D.O.O., BASF Belgium CCCV, Bayer CropScience SA-NV, Globachem N.V., Mitsui AgriScience International SA/NV and UPL Europe LTD) committed themselves to analyze the available monitoring data (2009-2019), to try to identify any clear correlations with the use of flufenacet-based products and to propose measures to reduce the number and level of exceedances.

Threshold values

To date, flufenacet is not considered a priority substance under the Water Framework Directive. There are no European water quality standards for this active ingredient. The current Emission Reduction Plan has taken into account the regional Environmental Quality Standards from 2010:

  • The threshold for acute exposure was set at 0,315 μg/L (MAC-EQS)
  • The threshold for chronic exposure was set at 0,167 μg/L (AA-EQS)


The currently authorized flufenacet-based products are all intended for professional use. However, until 2016 several products containing flufenacet for non-professional use were on the market. In practice, the use of flufenacet from 2016 onwards, consisted of its use in cereals (applied around October-November), maize and potatoes (applied around April-June).

Properties of the active substance

On the basis of the properties of the active substance, it can be concluded that flufenacet is a non-volatile, moderately persistent and moderately mobile herbicide.  


In general, a reduction in the number of locations and measurements with exceedances can be observed over the period 2009 – 2019. This reduction could be due to several restrictions in the use of flufenacet-based products, mainly for non-professional users. Further, campaigns from national and regional authorities and a prohibition for general use of plant protection products on communal grounds from 2015 probably had an important effect on the amount of pesticides applied for non-agricultural applications and subsequent release of flufenacet to surface water. Despite these restrictions, there are still exceedances observed in 2019 in a considerable number of monitored locations.

An in-depth analysis was performed to understand if the observed exceedances in surface water could be related to land use, erosion and/or weather patterns. Thereby, water bodies that registered frequent and/or persistent exceedances were investigated in detail. A clear seasonal pattern in Flanders and Wallonia with peaks in June and in November was observed. These peaks can be linked to the dominant crops in both regions. Especially in Flanders, the withdrawal of the authorizations for non-professional FFA use in 2016 resulted in a significant decrease of exceedances in June.

Flufenacet emissions through point losses, losses through erosion/runoff processes and to some extent sensitivity to drift were linked to high exceedance locations. The clustered growth of maize and potatoes in West Flanders was also identified as a risk factor. Furthermore, a less intensive cultivation of these crops potentially formed a risk of surface water exceedances when present on erosion sensitive fields.

In order to further reduce the release of flufenacet to surface water, several emission reduction measures are proposed by the authorization holders.

Emission reduction measures

Following crop-specific emission reduction measures will avoid further release of flufenacet in Belgian surface water:

  • As erosion is a potential source of flufenacet to surface waters, it is proposed to prohibit the use of the product on soils prone to erosion, unless precautions are taken to avoid erosion.Therefore, the SPe2 sentence* should be included on all flufenacet-based authorizations and labels.
  • On maize mandatory emission reduction measures such as a 20 meter vegetative filter strip on fields next to surface water will be further supported. Additionally, from the 2022 use season terbuthylazine based products can only be used every 36 months, also considering applications in the previous 36 months; which will also impact flufenacet use in maize since only combined products with terbuthylazine are authorized.
  • In potato the following emission reduction measure will be implemented: “On fields with very high erosion risk (purple fields) and high erosion risk (red fields) in Flanders & fields defined with an R-code in Wallonia, the implementation of microdams or the applications of low till practices are obliged, if these fields are adjacent to surface water or hard surfaces.”
  • For winter cereals, the use of flufenacet-based product will be limited: “Maximum 1 application of flufenacet-based products/crop”. Herewith, the number of possible application events is reduced and also the number of filling and rinsing of the spray tank; and therefore also the risk of point source contaminations, drift, erosion and run-off.

In order to be as efficient and transparent as possible, these measures should be included as limitations on all existing and new product authorization certificates. Furthermore, discussion is needed on how to control the implementation of these measures. This is considered a very important step to ensure the proposed measures are correctly followed.

Furthermore, continuation of product stewardship actions to prevent point losses and diffuse losses: awareness with regard to safe use (with leaflets, technical articles, …), further training in the frame of the phytolicense, promotion of the Fyteauscan to give farm-specific advice, further introduction of closed transfer systems will help to further increase the awareness of professional users on the impact of their behavior.

Ultimately, region-specific actions are recommended and considered in West-Flanders where there is a cluster of critical locations. Actions can be defined with regard to the prevention of point losses and diffuse losses.  

Towards the competent authorities, the authorization holders would like to advise to continue the monitoring campaigns, particularly at locations with regular threshold exceedances. The availability of monitoring data, sampled at the same location for several successive years with a regular interval (max. one month), would greatly help to derive the origin of contaminations, to better understand the fate of flufenacet in the environment over a longer time frame, and to evaluate the effect of the proposed emission reduction measures.

The authorization holders trust that the above measures and stewardship actions will lead to further emission reductions of flufenacet in Belgian surface waters.

*SPe2: To protect aquatic organisms the product cannot be used on erosion-sensitive parcels. For the Flemish Region and the Brussels Capital Region, this applies to parcels classified as “sterk erosiegevoelig”. For the Walloon Region, this corresponds to parcels identified with an R-code. In case precautionary measures against erosion are taken, as laid down in the regional legislations, the use can be allowed.