The Risk Management Challenge, George Gray

Center for Risk Science and Public Health

The Risk Management Challenge

George Gray

Center for Risk Science and Public Health Department of Environmental and Occupational Health

Milken Institute School of Public Health


Overview

•  What is risk management?

•  Different risk management principles

•  Mad Cow Disease - A Risk Management Challenge

•  Conclusions


What is Risk Management?

Process of making decisions about controlling health, safety and environmental risks

•  Cleaning up hazardous waste sites •  Setting air or water quality standards •  Developing fire or building codes •  Ensuring safe use of pesticides •  Informing consumers about products •  etc.


What is Needed for Risk Management?

Scientific and technical information

•  Size of risk •  Distribution of risk •  Sources of risk •  Control strategies •  Costs of controls •  etc.



•  Principles to guide decision making process

•  Who is to be protected? •  What is to be protected? •  What determines the appropriate level of

protection? •  Which risks should be addressed? •  etc.



Tools for risk management

•  Regulatory authority •  Public attention •  Economic incentives •  Voluntary agreements •  etc.


Overview

•  What is risk management?

•  Different risk management principles

•  Coke Oven Emissions - A Risk Management Challenge

•  Conclusions


Health-Based Risk Management

•  Stipulate level of protection that must be achieved without regard to technology, cost, or feasibility

•  e.g. Clean Air Act National Ambient Air Quality Standards - set standards to provide “ample margin of safety” for even the most sensitive groups

•  Zero risk even more stringent - don’t allow any source of risk

•  e.g. Delaney Clause of Food, Drug and Cosmetic Act


Health-Based Risk Management

•  Pros •  high level of health protection for all citizens •  assurance of “safety”

•  Cons •  ignores feasibility and cost •  ignores benefits •  potential substitution risks •  may require very stringent regulation to protect

sensitive subpopulations •  often contentious and slow – EPA frequently sued

to reevaluate NAAQSs


Technology-Based Risk Management

•  Require control technology for pollution reduction or treatment

•  e.g. Clean Air Act Amendments hazardous air pollutants provisions require maximum achievable control technology

•  Sometimes take account of feasibility or cost of technology •  e.g. Safe Drinking Water Act maximum contaminant levels

(MCLs) for carcinogens set as low as “feasible with the use of the best technology, treatment techniques and other means which the EPA finds after examination for efficiency under field conditions....are available (taking cost into consideration)


Technology-Based Risk Management

•  Pros •  straightforward to implement once technology is defined •  often relatively rapid

•  Cons •  defining “best” technology may be difficult •  technology may lead to too little pollution control or too

much •  encourages “end of pipe” controls rather than pollution

prevention •  “freeze” controls?


Benefit/Cost Risk Management

•  Attempts to explicitly balance the level of risk reduction with the cost of reducing the risk

•  e.g. Federal Fungicide, Insecticide and Rodenticide Act (FIFRA) attempts to prevent “unreasonable risk to man or the environment, taking into account the economic, social, and environmental costs and benefits of the use of any pesticide”

•  Principle advanced in Executive Orders 12866, 13563


Benefit/Cost Risk Management

•  Pros •  under ideal conditions finds optimal level of risk

reduction •  should lead to efficient allocation of risk reduction

resources - “save the most lives for the least money”

•  Cons •  some health and environmental benefits (and costs)

difficult to quantify •  other social considerations such as equity, size of

affected population, etc. may be important too.


The Precautionary Principle and Risk Management

"The precautionary principle applies where scientific evidence is insufficient, inconclusive or uncertain and preliminary scientific evaluation indicates that there are reasonable grounds for concern that the potentially dangerous effects on the environment, human, animal or plant health may be inconsistent with the high level of protection chosen by the EU".

February 2, 2000 European Commission Communication on the Precautionary Principle


The Precautionary Principle in Risk Management

Technology

Potential Hazard

Risk Assessment

Benefit/Cost Analysis

Risk Management

Precautionary Principle


Precautionary Principle

•  Pros •  Act in absence of “complete” information •  Act to protect future generations"•  Place “burden of proof” on risk generator

•  Cons •  Foregone benefit (Lack of access to a potentially risky

technology may have health cost e.g., HIV/AIDS drugs)

•  Risk tradeoffs (Precautionary actions may increase other risks e.g., UK vCJD and tonsil surgery instruments)


Information-Based Risk Management

•  Provide information to allow public to make their own risk reduction decisions

•  e.g. California’s Proposition 65 requires warning on any consumer product or food “known to the state to cause cancer or reproductive toxicity”

•  May operate through public pressure as well •  e.g. Emergency Planning and Community Right-to-Know

act requires manufacturing facilities to report emissions of chemicals on federally determined list of dangerous substances (the Toxics Release Inventory or TRI)


Information-Based Risk Management

•  Pros •  allows citizens to make their own informed benefit/cost

decision (Prop 65) •  companies can use most efficient method to reduce

emissions (TRI) •  Cons

•  over warning may lead to indifference (Prop 65) •  still need to establish appropriate level of protection •  great variation in toxicity of listed chemicals means

significant risk reduction not assured •  assumes value of reducing all listed chemicals is similar

(TRI)


Measures of a Good Decision

•  A decision which maximizes total social welfare is a good decision...

•  A decision arrived at by a fair process is a good decision...


Managing Risks - BSE

•  Imagine it is mid-2003

•  You have decisions to make about how the US responds to bovine spongiform encephalopathy (BSE or “mad cow disease”

•  Potential risk to animals and public health


What is BSE?

•  Bovine Spongiform Encephalopathy - commonly known as mad cow disease

•  A Transmissible Spongiform Encephalopathy (TSE) of cattle


Transmissible Spongiform Encephalopathies

•  Humans •  Kuru •  Crutzfeldt-Jakob Disease (CJD and nvCJD) •  Fatal Familial Insomnia, etc.

•  Animals: •  BSE (cattle) •  Scrapie (sheep and goats)) •  Chronic Wasting Disease (CWD) (deer and elk) •  Transmissible Mink Encephalopathy (mink) •  Feline Spongiform Encephalopathy •  Zoo animals


Characteristics of TSEs

•  All cause fatal spongiform changes in the brain

•  Long incubation period

•  Pathogenesis poorly understood

•  Infectivity often concentrated in CNS tissues

•  Infective agent unknown, current hypotheses focus on prions


The Odd Infectious Agent of TSEs

•  Very resistant to standard disinfection procedures •  Heat •  Radiation •  Acids or bases

•  Survive in tissues after death •  Not destroyed by refrigeration or freezing

•  Postulated to be small proteinaceous infectious particles - prions


The UK Outbreak

•  BSE apparently originated in the UK •  Identified in 1986 •  Nearly 180,000 cases identified in the UK since that time

Incidence of Confirmed BSE Cases in the UK

0500010000150002000025000300003500040000

1986

1988

1990

1992

1994

1996

1998

2000

2002

Year

Cas

es


BSE Spread Hypothesis

Rendering Feed BSE

Cattle Scrapie?

Spontaneous? Other?


The Spread of BSE

Country Cumulative Incidence

Country Cumulative Incidence

Austria 1 Italy 88

Belgium 114 Japan 9

Canada 2 Liechtenstein 2

Czech Republic 5 Luxembourg 2

Denmark 13 Netherlands 63

Finland 1 Poland 8

France 849 Portugal 823

Germany 273 Slovakia 12

Greece 1 Slovenia 3

Ireland 1303 Spain 343

Israel 1 Switzerland 448

As of mid-2003


BSE and vCJD •  BSE originally seen as animal health concern based on

experience with scrapie •  1995 new form of human TSE identified

•  Only found in countries with BSE •  Molecular and biochemical links to BSE •  Different signs and symptoms than classical CJD •  Fatal illness striking young people (average age 28 versus

63 in classical CJD) •  No strong epidemiologic link •  (new) variant Crutzfeldt-Jakob disease (vCJD)

•  vCJD now considered likely human form of BSE


vCJD Cases

Incidence of vCJD in the UK

0

5

10

15

20

25

30

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

Year

Cas

es

Through 07-05-2004

169 Total As of September 2010

http://www.cjd.ed.ac.uk/figures.htm


Managing BSE and vCJD Risk

•  Spread in cattle •  Prevent use of rendered cattle (or other ruminant)

protein in cattle feed (feed ban) •  Remove most infectious tissues from rendered

material (specified risk material ban)

•  Human exposure •  Remove most infectious tissues from human food

supply (specified risk material ban) •  Prohibit consumption of animals of advanced age

(over 30 month scheme) •  Test at slaughter •  Blood transfusion restrictions or treatments to

address hypothetical human to human transmission


BSE Spread Hypothesis

Rendering Feed BSE

Cattle Scrapie?

Spontaneous? Other?

Feed Ban


Managing BSE Risks

•  Implement feed ban?

•  Does source/risk of alternatives matter •  GM soybean meal? •  Amazon deforestation?

Agriculture, Ecosystems & Environment 120: 467-469


Managing BSE Risks

•  Specified Risk Material (SRM) Ban

•  Remove highest risk tissues from human food and from rendering process

•  Would reduce risks of “leaky” feed ban •  Reduce human risk

•  Significant costs to industry •  Disposal issues


Managing BSE Risks

•  Prohibit consumption of older animals

•  Studies suggest BSE infectivity very low until animals about 3 years of age

•  Reduce potential for human exposure

•  Significant disposal issues


Managing BSE Risk

•  Post-mortem test for BSE?

•  Remember, no BSE in US now

•  Reassure consumers and trading partners

•  5 kits approved in EU

•  False positive tests virtually certain


Managing BSE Risks

•  Ban on blood donations?

•  Some TSEs may be spread through blood (BSE has not shown infectivity in blood)

•  vCJD shows infectivity in lymph nodes – blood risk theoretical

•  Reduction in blood supply poses health risks

•  Local effects (NYC loses 25% of blood supply – imports and donors)


What Would You Do?

•  Feed Ban

•  SRM Ban

•  Over 30 Months

•  Post-mortem testing

•  Blood donation deferral


BSE/vCJD Risk Management Actions

UK EU USA BSE? Yes Yes No

(1986) (1990) Feed Ban? Yes Yes Yes

(1988) (1994) (1997) SRM Ban? Yes Yes No

(1989) (1997) 30 Month Rule? Yes No No

(1996) Post Mortem Test? No Yes No

(2000) Blood Donation Deferral? No No Yes

(leukodepletion) (1999)


Summary

•  Stringency of management measures appears to be roughly in line with BSE risk •  UK - many cases, most stringent measures •  EU - fewer cases, stringent measures •  US - no cases, serious measures but less than

UK or EU

•  Some question about proportionality of US blood donor deferral although similar to Canada and Australia


Perils of Precaution?

BBC Online: Saturday, 15 December, 2001, 05:30 GMT U-turn over tonsil operations

The government has been forced to make a u-turn on the use of re-usable surgical instruments for tonsil and adenoids surgery.

They had originally been withdrawn in January because doctors feared there was a theoretical risk of transmission of variant Creutzfeldt-Jacob Disease (vCJD) from re- usable surgical instruments.

However, following the change surgeons, found more patients than before were being harmed during surgery.

There was even one death linked linked to single-use instruments……... http://news.bbc.co.uk/hi/english/health/newsid_1692000/1692056.stm


Conclusions •  Risk management describes the series of tools for

controlling risks to human health and the environment

•  Must be based on scientific risk information •  identify size of risk •  identify opportunity for risk reduction •  quantify competing risks

•  Principles to guide management are necessary •  how to make decisions (efficiency or process) •  often mix of two

•  Sometimes risk is only a small part of a risk management decision

The Risk Management Challenge, George Gray

Government & Nonprofit

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