Evaluating POPs & PBT as part of the approval

Transcription

1 as part of the approval Peter Dohmen, 22 November 2011

2 Definitions / background Potential consequences Specific considerations: Compartmental approach Use of robust and relevant data Persistence Bioaccumulation potential / depuration Weight of evidence

3 Definitions / background New principle in Regulation 1107/2009 Hazard based cut-off criteria

4 Definitions / background Hazard based criteria for registration decisions they are rather easy to apply and easy to communicate generally made to be highly conservative, protective constitute a simplistic approach on a limited scientific basis with of low environmental relevance, The hazard based criteria in the new regulation result from a political decision, not from scientific needs

5 Definitions / background Regulation 1107/2009: PBT/vPvB An active substance, safener or synergist shall only be approved if it is not considered to be a persistent, bioaccumulative and toxic (PBT) substance.

6 Definitions / background Hazard based cut-off criteria in 1107/2009 CMR (1a and 1b) Endocrine POP PBT/vPvB

7 Definitions / background Specific features of PBTs Bioaccumulation in food webs Exposure and toxicity from the diet not always captured Chronic toxicity may be underestimated (carry over) Potential for secondary poisoning, All this is of particular concern for substances with limited (often only short term) data.

8 Consequences PBT substance. => No registration, no derogation 2 of 3 PBT characteristics: Candidate for substitution Subject to comparative assessment Impediment for mutual recognition Depending on interpretation / use of the different criteria, vast majority of all subsances are P and T, subject to comparative assessment and candidates for substitution

9 The new regulation for identifying PBT substances is not very detailed and further guidance is needed (Annex II with basic triggering schemes, but not specific enough to allow consistent scientific and regulatory decisions.) ECPA guidance proposal: based on 1107/2009 (cut-offs) adding further guidance based on scientific relevance while maintaining the ideas of this precautionary approach Clearly identify the critical substances while avoid loosing non-critical "false positive" substances

10 1107/2009 assessment process: First assessment by RMS Further steps may need more clarification: Role of Member States / EFSA / EChA? Data requirements unclear: Only lab data? Higher tier (e.g. field data)? Weight-of-Evidence (WoE) approach according to REACH Annex XIII?

11 ECPA proposal considering particularly the following points: Compartmental approach Use of robust and relevant data (incl. field, higher tier) Persistence Bioaccumulation potential / depuration Weight of evidence

12 1107/2009: "An active substance, safener or synergist shall only be approved if it is not considered to be a persistent, bioaccumulative and toxic (PBT) substance. A substance that fulfils all three of the criteria of the points (persistence, bioaccumulation, toxicity) is a PBT substance"

13 Relevant compartment The fundamental principle underlying all three of these schemes: combination of properties Consequently, in order to cause a concern the respective properties must co-occur This is the case if the combination of triggers relates to the same environmental compartment

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15 - Persistence Persistence 1107/2009: "Assessment of persistency in the environment shall be based on available half-life data collected under appropriate conditions, which shall be described by the applicant" DT50 fresh water > 40 d DT50 soil > 120 d Lab / field? Conditions, temperature? More than one value: mean value, worst case?

16 - Persistence Half-lives Used as Criteria for Identifying POPs / PBTs under Selected Frameworks UNECE CEPA EU- EU- USEPA USEPA PBT vpvb Moderate High action action level level 60 d 182 d 40 d 60 d 60 d 180 d Compartment Water UNEP 60 d Sediment 180 d 180 d 365 d 120 d 180 d 60 d 180 d Soil 180 d 180 d 182 d 120 d 180 d 60 d 180 d Other sufficient concerns sufficient concerns marine 60/180

17 - Persistence Recommendations from an international experts workshop: Assessment of persistence is a complex topic Use and release pattern System/ compartment properties Persistence cannot be directly measured Tonnage & rate of release Persistence Transport Volatilisation Sorption Dilution Advection Persistence is not an intrinsic substance property Substance properties Degradation Hydrolysis Photolysis Oxidation Reduction Biodegradation Cometabolism

18 - Persistence Residues in soil [µg/kg] measured residues 0 Sep Dec Mar Jun Sep Dec Time

19 - Persistence 10 Median = 33 8 DT 50 values soil Count 6 4 N= DT50

20 - Persistence Recent proposals from a MS to use DT50 values normalized to 12 C use OECD 309 for persistence evaluation in water use only lab studies Vast majority of compounds will be classified as P Present < 15-27%* 12 C > 60% * OECD 309 > 75% ** ** Estimate * ECPA / IVA evaluation

21 - Persistence Recommendations of the international expert workshop (SETAC Pellston Workshop, 2009) Assessment should involve careful analysis of all relevant data, weight of evidence. When range of half-lives available, then it is not appropriate to just use the slowest half-life; instead using a half-life in the higher end of the observed range or a measure such as geometric mean. In principle, results from higher tier studies (simulation tests) have greater environmental relevance. Therefore, they should have more weight.

22 - Persistence SCHER (Scientific Committee on Health and Environmental Risks): Chemicals and the Water Framework Directive - Draft Environmental Quality Standards Aclonifen, adopted at 12 th plenary, : No agreement to a temperature correction to 12 C of measured DT 50 data in the lab PBT criteria are not defined including a temperature correction, but simply at test temperature Test guidelines generally recommend room temperatures of about 20 C (e.g. OECD 307)

23 - Persistence Proposal of using 12 C as reference temperature Consequences: Compounds with DT 50 soil of 59 days at 20 C that do not need a field degradation study (because of low persistence acc. 1107/2009) but will have a DT 50 of > 120 days at 12 C => Persistence (acc. P hazard criteria)

24 - Persistence ECPA proposal: (a) The full range of (robust) data in a dossier (incl. environ./field data) is evaluated to assess persistence in the environment. ECPA recommends using geometric mean values for persistence. (b) For persistence in soil, normalised field DT50-values should be used for the setting of persistence triggers (best representation of persistence of the substance under concrete conditions of application)

25 - Persistence ECPA proposal: (c) For persistence in water, key should be dissipation from the water phase in water/sediment studies and aqueous photolysis/hydrolysis and/or adequate higher tier studies (if available). (d) For persistence in sediment, whole (water/ sediment) system degradation is more appropriate.

26 - Bioaccumulation 1107/2009; Bioaccumulation An active substance, safener or synergist fulfils the bioaccumulation criterion where the bioconcentration factor is higher than Assessment of bioaccumulation shall be based on measured data on bioconcentration in aquatic species. Data from both freshwater and marine water species can be used.

27 - Bioaccumulation Expert workshop concludes: The BCF is only a poor descriptor for a possible bioaccumulation in the food chain and should only be used as an initial screening step. The TMF (trophic magnification) finally determines the relevant concern caused by bioaccumulation. Most realistic data are most relevant; higher tier and field data should be utilized if available.

28 - Bioaccumulation Complex evaluation as proposed by the expert workshop is beyond the scope of the simple hazard trigger scheme. However, it is possible to utilize this BCF value more realistically by also considering the rate of depuration Substances depurated rapidly would be highly unlikely to biomagnify through the food chain. In line with recommendations from the aquatic guidance document which uses this criterion to identify persistent and bioaccumulating substances

29 - Bioaccumulation ECPA proposal: A CT 95 of > 14 days should therefore be used in addition to the current BCF trigger (i.e. BCF > 2000 and CT 95 > 14 d) If a substance is not stable in water, but only in sediment or soil, appropriate methods to evaluate bioaccumulation from those compartments should be used. As a standard rule BCF values should be calculated on the basis of substance concentrations rather than on TRR

30 - Toxicity ECPA proposal: When several data points are available for the same / taxonomic group of organisms, geometric mean values should be considered, representing a more robust approach, while providing an equivalent level of protection Algae/aquatic higher plants: E r C 50 value should be used instead of NOEC as recommended according to Classification, Labelling and Packaging Regulation 1272/2008

31 The same principals apply for identifying vpvb substances With regard to POPs, it is suggested to use the standard triggers and schemes of the internationally agreed "Stockholm Convention" including the parameter "potential for significant adverse effects"

32 Summary PBT and vpvb/pop substances are of particular concern Hazard criteria may provide a tool to identify potential critical substance; however, they are a poor tool if used as decision and management criteria

33 Summary ECPA proposal All three criteria need to be met together i.e. in the same compartment in order to cause PBT concerns Robust, harmonized and consistent data should be used (such as geomean, not extreme worst-case) Full evaluation of all relevant data, incl. higher tier data => Weight-of-Evidence approach (WoE)

34 Evaluationg POPs & PBTs Thank you for your attention