THE PRECAUTIONARY PRINCIPLEAND

COST-BENEFIT ANALYSIS

Risk Assessment

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 CancerSecond-hand smokeX-rays and CancerCell phones and CancerLead in paint, lead additive in gasolineAsbestos removal lawsSweetener bansFood recalls (spinach, tomato, beef this year)Speed limitsCarbon monoxide detector lawsHelmet 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?