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Applicant guide to providing suitable environmental exposure assessments for plant protection products

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The data provided by applicants must permit an assessment to be made of the fate and behaviour of the pesticide in the environment according to Regulation No. 1107/2009.

This information is subsequently used to assess the risk to non-target species (soil or aquatic organisms, plants etc.) that will be exposed to the pesticide formulation, its active substance(s), and the degradation products of the active substance(s). The information provided should be sufficient to:

It is the applicant's responsibility to ensure that all aspects of the product data requirements are addressed and that any risks are demonstrated to be acceptable in an appropriate way for the UK, as defined by Regulation No. 1107/2009.

Examples of changes that may affect the environmental exposure assessment:

Which end points should I use?

When compiling risk assessments for a product authorisation submission, you should use the end-points agreed at EU level (published in the current Review Report or EFSA conclusion for that active substance). However you will need to consider whether the end-points identified during the active substance approval process are appropriate to the products to be authorised.

Applicants may have information/data available that would support amore favourable end-point to that agreed in the EU. Where the assessment was acceptable using EU agreed end-points, there would be no need to consider the new end-point with the authorisation application.

There may be circumstances where a risk assessment conducted using EU agreed end points results in an unacceptable use. In these cases it would be appropriate for applicants to seek to amend an agreed end-point to allow consideration of the use.  However Applicants must demonstrate that the use of additional data is justified by providing a standard assessment using Annex I agreed endpoints. 

What guidance should I use?

Where an applicant is required to submit data to support new uses or significant changes to their product that affect the likely environmental exposure, then the data should be assessed in accordance with the latest guidance available at the time the application is made, in line with Art 36 (1) of Regulation No. 1107/2009.  This includes use of the latest versions of the environmental exposure models.  Where an applicant is not required to submit new data the latest guidance (and models) does not need to be applied as no new risk assessment is being undertaken.  Similarly where the risk envelope approach is used the latest guidance does not need to be applied as no new risk assessment is being undertaken.

In addition to the above guidance you should refer to Summary of New Guidance for details of when more up-to-date assessment methodologies should be used.

'Risk Envelope':

The risk envelope approach makes use of the idea that within a group of products and uses, there will be certain uses which represent the worst-case situation in each environmental compartment.

The proposed GAP of a product can be compared against the use patterns of existing authorised products, or the representative use of the most recent Community level assessment.

If the evaluation of an authorised product is considered to provide a more worst-case environmental exposure, then it can be said that the new product is within the 'risk envelope'. In other words, the previous evaluation is considered sufficient to demonstrate that the proposed uses for the new submission are without unacceptable risk. 

To compare products, the critical use pattern(s) of each should be identified.

Risk envelopes are assessed for each compartment (PECsoil, PECgw, PECsw, PECair) independently. Therefore you may find one product provides a risk envelope for PECsoil, and a different product provides a risk envelope for PECgw.

Guidance on the selection and suitability of risk envelopes can be found at Risk envelope suitability

Authorisation of Products with Multiple Crops/Uses

In producing submissions for the authorisation of individual products with multiple crops/uses, applicants are encouraged to limit the environmental exposure assessments to a worst case example in each environmental compartment in order that the 'risk envelope' can be clearly established. Applicants should note:

Some UK Considerations

Applicants must satisfy themselves that the approach taken encompasses the UK geoclimatic situation and agricultural practices. Some areas to consider are detailed below:

Extrapolation of data

For authorisation of new products, uses and changes to existing uses, the extrapolation of supporting data and risk assessments for authorised products containing that active substance should be considered. This may be addressed by comparison of the following critical aspects of the proposed use with that authorised.

Any comparison between products and their uses should critically assess whether the change in the product and/or pattern of use will result in increased levels of environmental exposure to both target and non-target environmental compartments. There are two possible outcomes from this initial critical assessment:

  1. there will not be increased levels of environmental exposure, in which case extrapolation to existing data will be possible and you will not need to submit additional information.
  2. increased levels of environmental exposure may occur, in which case you will need to submit a further assessment/reasoned case, often with additional supporting experimental data. This further assessment must enable the higher environmental exposure in the different environmental compartments to be determined

Further advice on providing suitable exposure calculations in the range of Environmental Compartments considered may be found by following the links below.


For acute assessment, the highest initial PECsoil (for persistent compounds, the peak plateau concentration);

For chronic assessment, (the requirement for which is triggered by the DT90 field value), in the first instance, the highest initial PECsoil (for persistent compounds, the peak plateau concentration) should be used.  If this does not result in an acceptable risk assessment, then depending on the ecotoxicity profile for the compound, an appropriate time weighted average value may be used.  Applicants are directed to Soil.


PECgw according to EU Forum for the Co-ordination of Pesticide Fate Models and their Use (FOCUS) guidance.

Applicants should check that the groundwater exposure assessment is relevant to the geoclimatic conditions in the UK.  Applicants should submit first tier FOCUS groundwater modelling with standard scenarios, the scenarios considered pertinent to UK conditions being: Châteaudun, Hamburg, Kremsmünster and Okehampton (see Groundwater).

Assessment of Groundwater Exposure from Use on Hard Surfaces

Where recommendations are made for use on hard surfaces, CRD guidance on assessment of groundwater exposure from such uses should be followed. Current guidance on calculating the PECgw for the UK from hard surface use is included at HardSPEC.

Surface Water and Sediment

For community level assessments and zonal assessments Applicants are directed to EU PECsw for additional information.

For UK specific assessments, 'following zonal' requests and 'Mutual Recognition' requests, Applicants are directed to UK PECsw for additional information.

Assessment of Surface Water Exposure from Use on Hard Surfaces

Where recommendations are made for use on hard surfaces, CRD guidance on assessment of surface water exposure from such uses should be followed. Current guidance on calculating the PECsw for the UK from hard surface use is included at HardSPEC.


Guidance is presently under development see Air.

Cases where environmental fate and behaviour data may not be required

There are patterns of product use where exposure to the external environment is limited following treatment, (eg permanent glasshouses, livestock sheds). Where products are used in this way, you may make a case for the non submission of environmental fate and behaviour data providing the recommended use specified on the label ensures containment.

However, potential secondary exposure to the environment should be addressed. Examples of where this may be necessary include:

Any queries can be discussed with HSE's Chemicals Regulation Division (CRD).

Updated 2016-12-01