Environmental Health and Toxicology

Question 1

Environmental Health

Answer 1

The study of how environmental contaminants impact human health

Question 2

Environmental health can be broken down by exposures, or the way you are exposed to a specific hazard:

Answer 2

Physical hazards
Chemical hazards
Biological hazards
Cultural hazards

Question 3

The major focus of environmental health is _.

Answer 3

Disease

Question 4

Disease can be broken down in to two categories:

Answer 4

Chronic disease
Infectious disease (accounts for 26% of the world's deaths; epidemiologic transition)

Question 5

Toxicology

Answer 5

The study of poisons (toxins) and how they impact the health of living organisms; the dose makes the poison

Question 6

_ of all US streams and rivers have at least trace amounts of synthetic toxins.

Answer 6

80%

Question 7

Carcinogens

Answer 7

Toxins that cause cancer; the largest source of cancer worldwide comes from synthetic chemicals; examples: Benzene (polycyclic aromatic hydrocarbon), ethylene oxide, aflatoxin, asbestos

Question 8

Mutagens

Answer 8

Toxins that cause mutations in the DNA of organisms; can lead to cancer, but mostly cause abnormalities in offspring; examples: sunlight, alkaloid plants

Question 9

Teratogens

Answer 9

Chemicals that cause harm to an unborn

Question 10

_ of all birth defects’ causes are unknown.

Answer 10

65%

Question 11

Allergens

Answer 11

Allergy causing agents that overstimulate the immune systems to incite a response that is unnecessary

Question 12

Neurotoxins

Answer 12

Chemicals that attack the central nervous system; mostly heavy metals, pesticides, and weaponry; example: Pb and Hg exposure decreases cognitive function

Question 13

Endocrine Disruptors

Answer 13

Chemicals that interfere with or mimic the endocrine (hormonal) system; excess estrogen in water due to birth control is leading to the feminization of the US; examples: Lake Apopka alligators, Taiwanese boys, Tyrone Hays

Question 14

Diseases can travel in different ways; these are called routes of exposure:

Answer 14

Inhalation (VOCs, Volatile Organic Compounds)
Ingestion
Dermal absorption
Blood infection

Question 15

Vector

Answer 15

Anything that carries a disease from one organism to another

Question 16

Bioaccumulation/Biomagnification

Answer 16

Some toxins can concentrate in certain areas, while others disperse and dilute

Question 17

Epidemiology

Answer 17

The study of disease occurrence; the idea is to link areas with high disease outbreak to particular outcomes; father is Charles White

Question 18

Toxicology Studies

Answer 18

Usually contain animal testing through dose-response relationships; LD50/IC50 (LD: lethal dose, IC: inhibitory concentration - for plants) what will kill/inhibit 50% of organisms; threshold values

Question 19

Acute Exposures

Answer 19

Short period exposures

Question 20

Chronic Exposures

Answer 20

Long term exposures

Question 21

Additive Effects

Answer 21

One bad chemical + one bad chemical = 2 bad effects; example: alcohol and caffeine

Question 22

Synergistic Effects

Answer 22

One bad chemical + one bad chemical = 2 REALLY bad effects; example: alcohol and ibuprofen

Question 23

Subtractive Effects

Answer 23

One bad chemical + one bad chemical = cancel each other out; example: red wine (or grape juice) and grilled food

Question 24

Risk Assessment

Answer 24

A tool used by toxicologists to take in to consideration the individual difference of people to help calculate risk; does risk match perception?; innocent until proven guilty approach vs. precautionary approach

Question 25

Precautionary Approach

Answer 25

FIFRA; of the 100,000 industrial chemicals in our country, only 10% have been tested for toxicity, 2% have been tested for carcinogenicity, mutagenicity, or teratogenicity, and less than 1% are government regulated; what about endocrine, nervous, and immune systems?