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Setting and Using Environmental Standards Highlights of SETAC workshop Faringdon, October 2006 Paul Whitehouse Chemicals Science Environment Agency.

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Presentation on theme: "Setting and Using Environmental Standards Highlights of SETAC workshop Faringdon, October 2006 Paul Whitehouse Chemicals Science Environment Agency."— Presentation transcript:

1 Setting and Using Environmental Standards Highlights of SETAC workshop Faringdon, October 2006 Paul Whitehouse Chemicals Science Environment Agency

2 SETAC workshop An opportunity to ‘take stock’ of technical developments wider aspects e.g. role of stakeholders in regulatory decision-making Scope chemicals  environmental receptors  human health (  ) microbes, radionuclides 

3 SETAC workshop - Working Groups Aquatic effects assessment Implementation Socio-economic issues Terrestrial effects assessment

4 Selected highlights  Types of standard  A process for delivering standards  Effects assessment - data and extrapolation  Implementing standards  Incorporating an economic dimension

5 Types of standard Statutory threshold - must not be exceeded Threshold that prompts action - not usually statutory An aspiration - not statutory ‘benchmark’ ‘trigger value’ ‘screening value’ ‘standard’ ‘limit value’ ‘goal’ ‘guideline’ Usually, but not always numerical always numerical, usually with accompanying conditions e.g. duration, confidence of failure, return period Failure can have serious implications (legal, financial) Costs and benefits important Implications of failure less serious Conservativism is appropriate

6 A process for developing standards PROBLEM FORMULATION DEVELOP SPECIFICATION DERIVE STANDARD IMPLEMENT STANDARD What is the standard intended to achieve? To what extent should economic factors influence the outcome? Who will be affected? How should the standard be expressed? Methodology - constraints? Who needs to be involved? Are the data adequate? Account for uncertainties Incorporate socio-economic factors Where is to be applied? How confident do we need to be before we take action? What will we do in the event of failure? Consistency across regulatory regimes Need for transparency - report assumptions, decisions, uncertainties Involve stakeholders Value of peer review

7 Effects assessment - overview

8 Data  Quality assessment of data important e.g. Klimitsch codes  acceptable - supporting - unacceptable  Relevance  demographic endpoints (survival, reproduction, development)  magnitude of effect (LOEC)  Reliability  test conditions stated  QA regime e.g. GLP  dose-response, taking account of limit of solubility  measured exposures  NOECS are bounded (I.e. there is an effect conc)  Data not generated to standard guidelines are acceptable

9 How to use field and mesocosm data in deriving thresholds?  Sometimes, we have substantial quantities of field data or data from mesocosm studies  But …  can’t always eliminate other stressors  goals of study may not always be consistent with those of standard (e.g. ‘soil fertility’ vs ‘protection of ecoreceptors’)  Use as critical data to derive a standard or to corroborate one based on lab data (i.e. adjust AF)?  Support for use as ‘driving’ data as long as study goals are consistent with those identified at Problem Formulation and other quality criteria are met

10 What level of protection? Threshold can protect against ‘no effects’ or A more conservative than B Screening values might be type A and mandatory standards more like type B ‘Warning’ and ‘Action’ limits May be useful as a way of setting bounds within which economic or policy factors can operate

11 ‘Horses for courses’ Selection of data: magnitude of effect e.g. EC10 vs EC50 Extrapolation: assessment factor or percentile at risk (e.g. HC5 vs HC10) Burden of proof before we will take action

12 Extrapolation methods - workshop view on reliability

13 Dealing with background  Principle of allowing for background accepted for naturally occurring metals and some organics e.g. PAHs  Assumes adaptation to background and hence need to manage only the anthropogenic fraction  ‘Added Risk’ currently the only feasible approach: Threshold = Background + Maximum Permissible Addition*  Can we reliably estimate a background?  should it include anthropogenic inputs (mining from 2000 years ago)?  distribution of backgrounds may have large variance - where to set the background?  What scale? Site-specific? Geotype? National? * PNEC derived from ecotoxicity testing

14 Dealing with background F F Background conc express as ‘total risk’ ? express as ‘added risk’ threshold = background?

15 The ‘Added Risk’ approach Env conc < threshold? NFW Determine background NFW Env conc < threshold + background? Take action Y Y N N

16 (Bio)availability  Metals can exist in different chemical forms - largely influenced by prevailing environmental conditions  Only a small proportion of total metal may be in a form that can be taken up or exert biological effects  Availability can now be predicted for a number of metals (e.g. ‘WHAM’, BLMs)  Accounting for speciation and availability can remove much of the scatter in conc-effect relationships [Total] [Dissolved] [Speciation-based] implementation costs increasing risk of false +/- increasing

17 Implementing a standard numeric value - only one part of a standard, especially if measurement required to determine pass/fail design risk - how often is it acceptable to fail? e.g. “1 in 20 years” period of time over which this statistic applies e.g. a year How often the limit may be exceeded (e.g. 5% of the time) - express standard as mean or percentile statistical confidence with which failure must be demonstrated before action taken (“burden of proof”)

18 “Burden of proof” threshold Concentration (or dose) F Do we give benefit of doubt to the environment … or polluter … or face value? If we give benefit of doubt to the ‘polluter’ then we require a higher level of confidence before taking action - effectively raising the standard (or increase sampling frequency) Depends on seriousness of failure?

19 Standards - social and economic aspects  Costs  of monitoring (regulators, industry)  of compliance e.g. limiting emissions so that the standard can be met Socio-economic analysis when significant risk of failure, investment implications, risks to certain sectors  Openness and consultation are now important ways of working  Regulators are required to address costs  Social and economic aspects of standards are dealt with through  Regulatory Impact Assessments  derogations because of disproportionate cost  non-implementation of standards

20 MCDA - options appraisal  Multi Criteria Decision Analysis is a technique for ‘balancing’ conflicting risks  Formal approach that involves identifying criteria against which we will make a decision, measuring preferences and finding an option that provides the best overall balance for a standard  Recently used to assess options for sheep dip chemicals, taking account of concerns about environmental protection, animal welfare, farmer livelihoods etc  Can include a ‘do nothing’ option  Robust scientific analysis is a key element - but other elements will also influence the standard  Participative and transparent - opportunity to involve stakeholders

21 Key points  Stepwise process with clear roles for policy, science and stakeholders  Technical groups largely ‘consolidated’ conventional practice  Methods emerging for dealing with backgrounds and bioavailability - ‘research to regulation’  Flexibility recognised in standards for different purposes - in the way standards are set and the way they are used  5 requirements of an ‘ideal’ standard  Recognise socio-economic realities - robust scientific analysis could be just one of a number of inputs to standard setting

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