Transcript g. Risk Assessment

Risk Assessment
THE PRECAUTIONARY PRINCIPLE
AND
COST-BENEFIT ANALYSIS
The Precautionary Principle
 “Better safe than sorry”
 “Always err on the safe side”
 More formally (and more controversially):
 “The lack of complete certainty is not a justification to do
nothing.”
If there is a reasonable suspicion of harm, AND …
 there is scientific uncertainty about cause and effect
THEN …
 We have a duty to take action to prevent the potential harm.


Burden of proof is on those who claim there is no risk.

(from the Science and Environmental Health Network)
Applied to Global Warming
 “The lack of complete certainty is not a justification
to do nothing.”



Is there is a reasonable suspicion of harm?
Is there scientific uncertainty about cause and effect ?
Do we have a duty to take action to prevent the harm?
 Are there downsides to consider if we “overreact” to
a non-crisis?

We’ll get back to this VERY complex example later.
Simpler Examples of P.P.











Tobacco and Lung Cancer
Second-hand smoke
X-rays and Cancer
Cell phones and Cancer
Lead in paint, lead additive in gasoline
Asbestos removal laws
Sweetener bans
Food recalls (spinach, tomato, beef this year)
Speed limits
Carbon monoxide detector laws
Helmet laws (minors, bicycles, cars … )
The Costs of Precaution
 Economic effects (Ex: of asbestos abatement)



increased cost to producers
job losses as employers layoff to cut costs
increased prices to consumers

businesses MUST profit to stay in business
 Quality of life issues (Ex: CAFE standards)

We could ban lead and mercury, but at what loss?
 Better use for the resources ($) (Ex: CO detectors)



How many lives do carbon monoxide detectors save?
Could those millions be better spent in cancer research, …?
My wife is far more likely to die of breast cancer than CO poisoning
 Unintended consequences

(Ex: DDT and malaria)
Must weigh Costs against the Benefits
Acceptable Levels of Risk
 Is a zero-risk life possible?
 don’t bungee-jump
 don’t smoke
 don’t drink alcohol
 don’t eat unhealthy foods
 don’t drive
 don’t have sex
 If not, how do we determine the acceptable risk
level?
Cost–Benefit Analysis
 Applying the financial analysis technique to policy
making and personal decision-making
 A more complicated alternative to the Precautionary
Principle
 Example: Cost-Benefit analysis of eliminating cell
phones, which may produce dangerous radiation.
Reacting to Global Warming
 What is the main cause of anthropogenic GW?
 What must be done to reduce our contribution to
GW, assuming there is one?
 What are the costs of doing the above?