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Environmental Fate - Don't forget!

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The following list of points relate to common reasons for requests for further information during CRD Fate evaluations of (mainly) PPP requests.

General - Submissions

Please ensure the application is clear in stating how it is intended to address each area of environmental exposure, ie soil, groundwater, surface water/sediment and air (if appropriate).

For all GAPs, Please provide the earliest and latest time of application and interval between applications.

For all GAPs: Please explain why the risk envelope is appropriate for different crops etc.

Use of new active substance data must be fully explained.

When using the risk envelope from the Annex 1 assessment, care should be taken to ensure new crop interception values and latest model versions have been used. It is not acceptable to use the Risk Envelope from the Annex I assessment for product authorisations where 'old' interception values or old model versions have been used.

General - PEC calculations

Please use the EFSA / EU agreed Annex I listing endpoints (as the basis for all first tier environmental exposure assessments).  Please also ensure that all input parameters and model assumptions necessary to run the environmental exposure are clearly tabulated in your submission.

Where EFSA / EU agreed Annex I endpoints  are not used in higher tier or refined assessments, a clear justification and must be included.

All sources of new input parameters used in PEC calculations must be referenced, eg if new studies have been submitted and values have changed from the Annex 1 agreed values or from values previously used in applications by the same company.

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 and see also Summary of new Guidance.

Please ensure that the calculations are in line with the correct GAP (and cover early and late applications for different crop interceptions, application dates and spray drift values {ensuring the correct late/early spray drift values are utilised})

It is not always possible to identify a risk envelope based on highest application rate alone, when often lower application rates at earlier growth stages on different crops may actually be the worst case – applicants should provide PEC s for all uses and then decide which is the risk envelope as it won't be the same use for all areas of the risk envelope.

Please ensure that only essential metabolite calculations are produced ie where uses are outside an existing risk envelope.  Note that for product authorisation submissions CRD would only expect Applicants to address the risks arising from ecotoxicologically relevant metabolites (as defined by the EFSA conclusion)

Please ensure the appropriate Q10 is utilised in modelling simulations (ie when normalisation utilised 2.2, 2.58 should not be utilised within the modelling).

Simple tier 1 PECsoil calculations must be made with longest DT50 rather than geomean DT50 (refer to the endpoint used for calculating PECsoil at Annex I level for future product authorisation submissions).

Sensitivity of higher tier modelling to application date should be fully investigated;

When running the FOCUSsw models, please ensure you include details of application windows assumed, the application dates selected and indicate whether exposure arises predominantly from spray drift, runoff or drainflow in each scenario.

Where a formulation PECsw is required for a zonal submission, Applicants should use the drift calculator within SWASH and assess exposure via spray drift for a single application only.

Please note new soil degradation endpoints for 1,2,4-triazole to be used in preparing risk assessments:

The table below summarises the new endpoints, which arise from the biphasic kinetic parameters. However, in order to understand how these values have been calculated in accordance with the FOCUS Degradation Kinetics Report (2006), interested parties should refer to the full details of the DFOP kinetic parameters presented in the CRD 'evaluation document' dated January 2013 (this is the document considered at the Standing Committee).

DT50/DT90 normalised to 20°C/pF2 for environmental exposure modelling purposes

Soil type
Location pH Depth (cm) Overall degradation g Fast phase Slow phase St.
Method of calculation
DT50 (d) DT90 (d) DT50
DT50 (d)

Silt loam











Silty clay loam











Sandy loam






















Geometric mean





Arithmetic mean


These revised values have been considered by Member States and EFSA and were formally noted at the Standing Committee on the Food Chain and Animal Health on 13 December 2013.

These new values are, therefore, applicable at EU level and should now be used by applicants in the assessment of applications for new product authorisations, or applications to amend authorisations for existing products. The new values have been applied by the UK since December 2013.

The review reports for the affected triazole active substances have yet to be amended to reflect these new values, hence this Regulatory Update to publicise the new values to be used in preparing risk assessments.

Additional UK national requirements

For all UK uses, the environmental exposure calculations must use UK specific methodology.

Note precedents set under COPR are unlikely to be appropriate for post Annex I listing authorisations and precedents set under 91/414 may not be appropriate for Post Annex I Renewal authorisations

Submission of FOCUS Surface Water is not appropriate for UK assessments;

Failure of the first tier drainflow assessment requires higher tier assessment to be submitted;

Please include Groundwater MACRO modelling when Koc >100 ml/g.

Parameterisation of higher tier drainflow studies must be fully explained and justified.

Drainflow must be considered an issue even where application of pesticide is made outside 'outside drainflow period' until it is shown not to be an issue.

UK drainflow calculations are required for applications to potatoes.

Formulation PEC calculations also required for soil and UK spray drift assessment.
Updated 2017-07-11