Risk Assessment

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Risk Assessment

• April 10, 2006

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Risk Assessment

• Procedures based upon.Risk Assessment Guidance
  for Superfund, Volume 1 - Human Health
  Evaluation. Known as RAGS Issued by EPA in 1989
• 1. Data collection and analysis
• 2. Exposure assessment
• 3. Toxicity assessment
• 4. Risk characterization

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Dose-Response
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Dose-Response Curve
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Calculating Reasonable Maximum Exposure

• CDI C(CR)(EDF)/BW1/AT
• CDI chronic daily intake (mg/kg body weight)
• C chemical concentration (e.g. mg/L)
• CR contact rate (e.g. L/day)
• EFD exposure frequency and duration (days)
• BW body weight (kg)
• AT averaging time (period of exposure in days)

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Example - Risk of Cr(VI) in vapor

• Estimate the risk from occupational inhalation
  exposure to hexavalent chromium for the
  recommended concentration of 0.05 mg/m3. Assumes
  healthy individual working 8 hr/day over working
  lifetime (age 18 - 65). Equates to 8 hr/day, 5
  day/week, 50 week/yr. Use average body mass and
  inhalation rate. Assume lifetime is 70 years.