1. APES 4/10 1. Unit 11B Notes 2. Introduce Risk Lab- pick groups 3
APES 4/ Unit 11B Notes 2. Introduce Risk Lab- pick groups 3. Bring a bottle to class tomorrow Glass or plastic 4. Homework- Watch 10 Americans Video and Answer Questions---bring in printed copy tomorrow. Spring Break Extra Credit Due Today On the handout write specifically where you want your bonus points to go
See your agenda for upcoming test/quiz dates

2. Unit 11B Environmental Risks & Toxicology
Environmental Health, Risk, Pollution and Toxicology

3. Risks and Hazards
Risk: possibility of suffering harm from a hazard that can cause injury, disease, economic loss or environmental damage.
risk expressed as a probability;
risk assessment using data, hypotheses and models to estimate the probability of harm to human health, society, or the environment that may result from exposure to specific hazards

4. What are the greatest risks to humans in the U.S.?
Poverty poses the greatest risk
shortens lifespan by 7–10 years
Smoking and being overweight
pose the next greatest risk
each shortens lifespan by 6 years
Being born male poses a greater risk than being female (shortens lifespan by 7.5 years);
Being unmarried is associated with risk
shortens lifespan by 5 years

5. Other Risks… other significant risks in the U.S. include
second-hand smoke
Driving
air pollution
alcohol use
drug abuse

7. The FOUR Major Hazards
Cultural hazards - unsafe working conditions, smoking, poor diet, drugs, drinking, driving, criminal assault, unsafe sex and poverty)
Chemical hazards - harmful chemicals in air, water, soil and food
Physical hazards - noise, fire, tornadoes, hurricanes, earthquakes, volcanic eruptions, floods and ionizing radiation
Biological hazards - pathogens, pollen and allergens & animals (bees and poisonous snakes)

8. Toxicology
Toxicology is the study of the adverse effects of chemicals on health.
Toxicity is a measure of how harmful a substance is;
Dose - the amount of a potentially harmful substance that is ingested, inhaled, or absorbed through the skin

9. Response Response is the resulting type and amount of damage to health
Two types of responses:
Acute effect: immediate or rapid harmful reaction, e.g., dizziness, rash, death
Chronic effect: permanent or long–lasting consequence, e.g., asthma, kidney damage, heart

10. Bioaccumulation & Biomagnification
The pesticide DDT becomes increasingly concentrated high in the food chain because it is stored in fatty tissue and not easily broken down or excreted
Bioaccumulation - results when the concentration of a
chemical in specific organs or tissues is higher than would normally be expected.
Biomagnification - involves magnification of concentrations as they pass through the food chains and webs.

11. Measuring Pollutants Measuring depends on the substance Common Units
ppt: parts per thousand
ppm: Parts per million
ppb: Parts per billion
Micrograms per cubic meter (measures air)

12. Categories of Pollutants
Infectious Agents
Toxic Heavy Metals & Organic Compounds
Radiation
Thermal Pollution (Heat)
Particulates
Asbestos
Electromagnetic Fields
Noise Pollution
Voluntary Exposure

13. Organic Compounds
Organic Compounds: composed of carbon, making up living tissue
Synthetic Organic Compounds: used in industrial processes
Persistent Organic Pollutants (POPs): Synthetic organic compounds often containing chlorine, that do not easily break down in the environment.
Hormonally Active Agents: Chemicals in the environment able to cause reproductive and developmental abnormalities in animals (endocrine disrupters)

14. Stockholm Convention on Persistent Organic Pollutants
An international environmental treaty
Signed in 2001 and effective from May 2004
Aims to eliminate or restrict the production and use of persistent organic pollutants (POPs).

15. Determining Toxicity Three methods of determining toxicity:
Case reports (usually to physicians) about health effects after exposure to a chemical;
Epidemiology, involving studies of populations exposed to certain chemicals or diseases
Laboratory investigations (usually with test animals… like sea monkeys)

16. Concept of Dose and Response
The effect of a certain chemical on an individual depends on the dose.
Individuals differ in their response to chemicals
Threshold Effects:
the level below which effects are not observable and above which effects become apparent

17. LD 50 - is the median lethal dose, the amount of a chemical received that kills 50% of animals;
A poison is legally defined as a chemical that has an LD 50 of 50 milligrams or less per kilogram of body weight.
You may also see TD-50

18. What are toxic vs. hazardous chemicals?
toxic chemicals are generally defined as substances that are fatal to over 50% of test animals (LD50) at given concentrations.
hazardous chemicals cause harm by
being flammable or explosive (e.g., gasoline);
irritating or damaging the skin or lungs (e.g., strong acids or alkalines such as oven cleaners);
interfering with or preventing oxygen uptake and distribution (e.g., carbon monoxide, CO);
inducing allergic reactions of the immune system (allergens).

19. Mutagens, Teratogens, and Carcinogens
mutagens are agents, chemicals and radiation, that cause random mutations, or changes in the DNA;
teratogens are agents (chemicals, radiation, or viruses) that cause birth defects;
e.g., PCBs, steroid hormones, heavy metals;
carcinogens are agents (chemicals, radiation, or viruses) that cause cancer;
over 100 types of cancer (depending on cells involved);
e.g., cigarette smoke.

20. Biological Hazards
Biological hazards include both non-transmissible and transmissible diseases.
Non-transmissible diseases are not passed from one person to another, e.g., cardiovascular disorders, most cancers, diabetes, emphysema and malnutrition;
Transmissible diseases are caused by bacteria, viruses, protozoa, or parasites, and can be passed from one person to another, e.g., colds, flus, hepatitis, sexually- transmitted diseases, malaria;
some transmissible diseases are spreading over broad geographic areas as the result of human activity;
e.g., Lyme disease carried by ticks and spread by people is now widespread over North America.

21. Risk Lab- pick groups 5 or fewer Every person must survey 12 people—do not survey APES students or anyone younger than 16. You will combine data on Wed. Make sure you have all of your data in class. Reminder: Bring a bottle to class tomorrow Glass or plastic Homework- Watch 10 Americans Video and Answer Questions---bring in printed copy tomorrow.

22. What are some ways we can reduce infectious diseases?
reduce overcrowding, unsafe drinking water, poor sanitation, inadequate health care systems, malnutrition and poverty
increase funding for disease monitoring
sharply reduce antibiotic use to prevent evolution of resistant organisms
protect biodiversity as a means of reducing disease spread
increase research.

23. Additional Terminology
Contamination: making something unfit for a particular use through the introduction of undesirable material
Synergism: the interaction of different substances resulting in a total effect greater than the sum of the effects of the separate sources

24. Precautionary Principle
The idea that in spite of the fact that full scientific certainty is often not available to prove cause and effect, we should still take cost-effective precautions to solve environmental problems where there exists a threat of potentially serious and/ or irreversible environmental damage