Chapter 15 Environmental Health, Pollution, and Toxicology

Vocabulary  Toxicology science that studies chemicals  Pollution vs. Contamination unwanted change vs. unfit for a use  Toxin vs. Carcinogen  pollutant vs. pollutant increases risk of cancer

Measuring Pollution Pesticides- ppm or ppb 100 ppm = 100 mg/kg = 0.01% ? ppm = 1.0% Water Pollutants- Density water 1g/cm 3 1ppm = mg/L ? ppm = µg/L ? ppm = µg/L Air Pollutant mg / m 3 3G salt in 3 metric tons of popcorn = 1ppm

Categories of Pollutants 1. Infectious agents 2. Toxic metals 3. Organic compounds 4. Radiation 5. Thermal Pollutants 6. Particulates 7. Asbestos 8. Electromagnetic fields 9. Noise pollution 10. Voluntary exposure

1. Infectious agents Interaction between humans and food, soil, water, air. These include environmentally transmitted diseases- Legionnaires’ disease, Giardiasis, Salmonella, Malaria, Lyme disease, Anthrax

Toxic Heavy Metals  Hg, Pb, Cd, Ni, Au, …….. P. 300  By products of refineries, mining  Direct toxic physiological effects -stored and accumulate fatty tissue, known as body burden -human body- 150 mg lead compared to 13 mg mercury  Potential pathway -biomagnifocation accumulation of a substance as moves through food web

Organic Compounds  Persistent compounds PCB, Aldrin, DDT, Endrin, Dioxins  Hormonally Active Agents (HAAs) Herbicides, plastics, pesticides affect endocrine system ( thyroid, pancreas, ovaries, testes, pituitary)

Electromagnetic Fields Electric appliance, transmission lines, electric motors Electric appliance, transmission lines, electric motors Do these pose a health risk? Do these pose a health risk? -Study showed children 1 to 3 times more likely to develop leukemia if exposed to EMFs -Others inconclusive

Dose and Response Dose-response curve Dose-response curve LD-50- lethal dose- 50% population die ED-50- effective dose- 50% of population show desired effect such as lower cholesterols TD-50- Toxic effects to 50% population such a nausea, slurred speech, etc.