TOXICOLOGY III

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TOXICOLOGY III

• Risk Assessment

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Whats the Risk?

• Risk- The probability that something harmful will
  happen.
• Chemical Risk The probability of harm caused by
  Chemical exposure.
• Acceptable Risk Is determined using scientific
  data and human judgment.

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HOW SAFE IS SAFE ENOUGH?

• Risk Assessment A process to determine how safe
  is safe enough.
• Answer Two Questions
• What health problems could this chemical cause?
• How likely are these health problems to occur?

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HOW SAFE IS SAFE ENOUGH?

• Summary of Risk Assessment
• Chemical Risk Toxicity X Exposure
• Toxicity- What health problems are associated
  with various doses or concentrations.
• Exposure- How much chemical a person is likely to
  get (from any source)

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HOW SAFE IS SAFE ENOUGH?

• High chemical risk requires both high toxicity
  AND exposure.
• May household chemicals are highly toxic but
  proper RISK MANAGEMENT can reduce risk.

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WHAT ARE THE TRADE-OFFS?

• Risk Management involves choices.
• How safe is safe enough?
• How importance is convenience vs. safety?
• How much money is protection from a risk worth?

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WHAT ARE THE TRADE-OFFS?

• One Risk Vs. Another
• Sometimes to lessen one risk you have increase
  another type of risk.
• Example spraying to control mosquitoes that
  carry West Nile virus.
• Topic West Nile virus
• Go To www.sciLINKS.org
• Code ATR05
• Topic Stream/river pollution
• Go To www.sciLINKS.org
• Code ATR06

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WHAT ARE THE TRADE-OFFS?

• Example Chlorine in water can form a carcinogen.
  Is it worth the risk?
• 25 million people/year die from unsafe water.
• ¼ of hospital patients are there from unsafe
  water.
• Topic Water Treatment
• Go To www.sciLINKS.org
• Code ATR07

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WHAT ARE THE TRADE-OFFS?

• Risk Vs. Cost
• If chlorine is dangerous how much will you pay
  for a different treatment?
• For Hazardous waste sites in Massena. How clean
  is clean enough?

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WHAT ARE THE TRADE-OFFS?

• When the EPA does a risk assessment they ask
• What contaminants exist at the site?
• How are people exposed to them?
• How dangerous could the contaminants be to human
  health?
• What contaminant concentrations are considered
  acceptable?

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WHAT ARE THE TRADE-OFFS?

• The closer you get to total clean-up the greater
  the cost.
• Chemical risk decisions are usually tough.
• There are almost always trade-offs.

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Summary

• Risk Assessment is a tool for figuring out which
  problems are most worth worrying about.
• Risk Management helps us
• evaluate approaches.
• Set priorities
• Choose best approach for keeping risks
  acceptable.