Course: BLD 159 Intro to Brownfield Remediation, Land Re-use, and Public Health

Reading: Risk Assessment

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Risk Assessment: Exposure and Health Effects

How does exposure occur?

- Pathways (recognizing that one or more may be involved)
  - Air
  - Surface Water
  - Groundwater
  - Soil
  - Solid Waste
  - Food
  - Non-food consumer products, pharmaceuticals
- Routes (and related human activities that lead to exposure)
  - Ingestion (both food and water)
  - Contact with skin
  - Inhalation
  - Non-dietary ingestion (for example, "hand-to-mouth" behavior)

What does the body do with the environmental hazard and how is this impacted by factors such as age, race, sex, genetics, etc.?)

- Absorption - does the body take up the environmental hazard
- Distribution - does the environmental hazard travel throughout the body or does it stay in one place?
- Metabolism - does the body breakdown the environmental hazard?
- Excretion - how does the body get rid of it?

What are the health effects?

- Example of some health effects include cancer, heart disease, liver disease and nerve disease.

How long does it take for an environmental hazard to cause a toxic effect? Does it matter when in a lifetime exposure occurs?

- How long?
  - Acute - right away or within a few hours to a day
  - Subchronic - weeks or months (for humans generally less than 10% of their lifespan)
  - Chronic - a significant part of a lifetime or a lifetime (for humans at least seven years)
  - Intermittent
- Timing
Is there a critical time during a lifetime when a chemical is most toxic (e.g., fetal development, childhood, during aging)?

Click here to access the Center for Hazardous Substance Research Human Health Risk Assessment fact sheet.  Read through this 2-page fact sheet.