Policy roundtable risk assesment and management at epa
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Policy Roundtable: Risk Assesment and Management at EPA. Prepared by Chris Dockins Will Wheeler U.S. EPA, National Center for Environmental Economics for Estimating the Benefits of Homeland Security Policies September 23, 2010. EPA Risk Assessment Documents. 2008. The “Red Book”

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Policy roundtable risk assesment and management at epa

Policy Roundtable: Risk Assesment and Management at EPA

Prepared by

Chris Dockins

Will Wheeler

U.S. EPA, National Center for Environmental Economics

for

Estimating the Benefits of Homeland Security Policies

September 23, 2010


Epa risk assessment documents

EPA Risk Assessment Documents

2008

The “Red Book”

Defines the risk assessment / risk management framework


Roles of risk assessment

Roles of Risk Assessment

Risk Assessment

Risk Management

Risk Assessment

- cancer

- non-cancer

Policy Decision

- standards

- information

Protective


Roles of risk assessment1

Roles of Risk Assessment

Risk Assessment

Risk Management

Risk Assessment

- cancer

- non-cancer

Policy Decision

- standards

- information

Protective

  • Economic Analysis

    • benefit-cost analysis

    • cost effectiveness

    • economic impacts

Predictive

Public Information


Overlaying the frameworks

Overlaying the frameworks

Typical tasks for Risk Assessment

Typical tasks for Economists


Overlaying the frameworks1

Overlaying the frameworks

Choices in risk assessment constrain the economic analysis

Typical tasks for Economists


Overlaying the frameworks2

Overlaying the frameworks

Choice of endpoint(s)

Risk or hazard measure

Estimating risk changes

Typical tasks for Economists


Raba project

RABA Project

Assemble a team to develop risk assessments for benefits analysis (RABA)

Toxicologists, biostatisticians, economists, epidemiologists

Begin with some mutual education

Base the analysis on actual data from a known (but undisclosed) chemical “Chemical T”

Known mode of action

Cancer and non-cancer effects

Make assumptions about exposure

Develop benefit-transfer estimates for benefits.


Objects of choice endpoint s

Objects of Choice / Endpoint(s)

  • Defining outcomes compatible with economic benefits analysis that could be inferred from analysis of animal data

    • Change in liver weight was the most sensitive effect

    • Usual approach would be to focus on liver weight or on T4/TSH hormone levels

    • Extensive discussion  move from modeling T4/TSH to modeling an outcome (hypothyroidism) that is amenable to valuation

  • Chemical T is also a carcinogen


Quantitative measure

Quantitative Measure


Quantitative measure1

Quantitative Measure

noncancer Reference Doses and Reference Concentrations are not risk estimates - but rather safety assessments

dose without “appreciable” risk of adverse effects

Reference dose tells us nothing about risks

What are the benefits of moving from must above to just below?

What are the benefits of additional reductions below the RfD?

Need to relate continuous data to probably of hypothyroidism

Approach: define 95th percentile TSH in controls as representing effect (hypothyroidism); sensitivity analysis of selected cutoff (Gaylor & Slikker 1990 method)


Change in objects of choice estimating risk changes

Change in Objects of choice / Estimating Risk Changes

Cancer potency values (particularly those using animal data) are generally derived by:

estimating a “Point of Departure” - a lower-bound estimate of the dose associated with a particular level of tumor incidence (typically 10%)

drawing a straight line from the POD to the origin

These procedures are generally characterized as producing an “upper-bound” estimate of cancer risk

assumption of low-dose linearity and lower-bound POD is not a central estimate

These may also be combined with “upper bound” exposure assessments

The resulting values will bias benefits analysis if used directly


Cancer and non cancer risks for valuation

Cancer

Hypothyroidism

0.6

0.4

%Lifespan = 0.1

Probability of Effect

0.2

%Lifespan = 1.0

0.0

2.5

0

5

10

15

20

25

30

Human Equivalent Dose (mg/kg/d)

Cancer and non-cancer risks for valuation

Combined with assumed (central) exposure parameters and benefit-transfer we can estimate benefits

The process and the outcome are not standard under our current framework


Silver book framework

Silver Book Framework


Next for epa s framework

Next for EPA’s Framework

October EPA Risk Assessment Forum colloquium to evaluate “Silver Book” recommendations, including revising EPA’s framework for risk assessment and management

emphasis on improving the utility of risk assessment

economic analysis is part of the discussion

Some exploratory analyses for upcoming rulemakings


Pros and cons

Pros and Cons

In some situations risk paradigm has been very successful

Some programs can justify their rules based on a risk assessment plus benefit-cost analysis very easily

E.g., EPA’s air office

Relatively easy-to-model risk

Relatively few pollutants

However, other programs within EPA have not been able to monetize benefits as easily

Tendency for risks that are not measured to drop out of consideration entirely

Heavy reliance on risk paradigm can squeeze out other approaches

Inertia, ingrained culture, and incremental budgeting can get you stuck


Sdwa rule disinfection byproducts

SDWA Rule: Disinfection Byproducts

1997 rule that controlled ‘leftovers’ in drinking water from treatment (e.g., chlorine)

Range of cancer risk: 1 case to 10,000 cases annually

This range of uncertainty led EPA to perform two additional analyses: breakeven and regrets analysis

Compared “no action,” regulatory alternative, and a stronger option


Breakeven analysis

Breakeven analysis

Take what you (assume) you know the most accurately and see what the levels of what you do not know have to be to break even

Used when you know (e.g.) costs and value of risk reduction, but not actual risk

Calculate cost and value of risk reduction

What is the risk reduction that allows you to break even? Is this risk reduction believable/reasonable?

Regulatory option would need to reduce 438 cancer cases per year to break even

Towards the low end of the 1-10,000 case range


Regrets analysis

Regrets Analysis

If you are wrong about risk, which option minimizes the damage

Used when there is a lot of uncertainty about risk

Calculate cost and value of forgone risk reduction for different policies and level of risk

What option minimizes losses for each alternative?

Worst losses

No action: $4 billion

Regulatory alternative: $0.7 billion

Stronger option: $2.9 billion


Epa employment

EPA Employment

EPA founded in 1970

Numerous statutory authorities

Risk Assessment gradually took hold

Cost-benefit requirements in the 1980s

Distribution of employees may not reflect new mandates


Epa professional emploment 2009

EPA Professional Emploment, 2009


Epa s office of research and development

EPA’s Office of Research and Development

EPA’s Office of Research and Development used the risk assessment paradigm in their 1996 Strategic Plan

Funding depended on contributions to reducing uncertainty in risk assessment

Economics hovered around one-third of one percent of research budget

Incremental budgeting also a factor

2001 Strategic Plan dropped this approach

Ecological Research Program recently adopted view of including economists

Can also blame inertia and incremental budgeting


Our advice

Our Advice

Decide where you want to be down the road and plan how to get there

Do not get stuck where you do not want to be


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