Human Health and Risk Assessment

Protecting Human Health Efficient Use of Limited Resources Causes of death: Disease Lifestyle Factors Toxins Symptoms and Causes Laboratory Studies Epidemiological Studies

Should we protect people from themselves?

Environmentally-Based Health Issues Toxins and Exposure 50 years later, victims of Minamata Disease still fight for justice New America Media, Commentary, Christopher Reed, Apr 26, 2006

Environmental Racism

Asbestos Microscopic view of lung tissue with asbestosis. Asbestos fibers lodged in the lungs. Asbestos-related conditions affect the lungs and surrounding tissues

Effects Carcinogens Mutagens Teratogens Toxins Synergisms Antagonisms Multiple Effects

Differences in Effect: Sensitive Receptors Children –Longer exposure –Developing tissues –Higher exposures? Elderly Respiratory Disease Genetics

Dose Response Curve

Quantifying Health Effects Table 2: Toxicity Classes: Gosselin, Smith and Hodge Probable Oral Lethal Dose (Human) Toxicity Rating or Class DoseFor 70-kg Person (150 lbs) 6 Super ToxicLess than 5 mg/kg 1 grain (a taste - less than 7 drops) 5 Extremely Toxic5-50 mg/kg4 ml (between 7 drops and 1 tsp) 4 Very Toxic mg/kg30 ml (between 1 tsp and 1 fl ounce) 3 Moderately Toxic g/kg ml (between 1 fl oz and 1 pint) 2 Slightly Toxic5-15 g/kg ml (between 1 pint to 1 quart) 1 Practically Non- Toxic Above 15 g/kgMore than 1200 ml (more than 1 quart)

Four steps of Risk Assessment Hazard Identification –Laboratory vs Epidemiological Studies Dose-response Exposure Assessment Risk Characterization versus The Precautionary Principle

The Delaney Clause

Ecological Risk Assessment Consequences of a shift to biomass energy Water diversion in dry areas Herbicide use in eutrophic aquatic systems

Factors in Understanding Environmental Toxicity Persistence Bioaccumulation Biological Magnification Water Quality in Southern Florida Florida, 1996–98