EHST 2110 ECU EXAM 3 UPDATED QUESTIONS AND CORRECT ANSWERS

EHST 2110 ECU EXAM 3 UPDATED QUESTIONS
AND CORRECT ANSWERS

Question:
1. Toxic
Answer:
a chemical that provokes an adverse systemic effect on living organisms

Question:
2. Toxicants
Answer:
can harm organs or biochemical processes away from place on body where exposure occurred

Question:
3. Poison
Answer:
chemical that can cause illness or death at a very low dose of exposure

Question:
4. How much poison exposure is lethal for an adult? child?
Answer:
3/4 of a tablespoon for adults, 1/8 of a tablespoon for toddlers

Question:
5. Toxicology
Answer:
the study of toxic substances

Question:
6. Dose-time relationship
Answer:
amount of chemical and duration of exposure

Question:
7. Acute toxicity
Answer:
one time exposure can cause harm; ex: kids eating rat poison

Question:
8. Chronic toxicity
Answer:
repeated low-dose exposures to chemicals; ex:lead toxicity

Question:
9. Routes of exposure

,Answer:
oral, dermal, respiratory

Question:
10. Are different species affected differently by toxins?
Answer:
yes, rats react differently than humans

Question:
11. LD
Answer:
the amount of a chemical required to kill 50% of a population of test animals within 14 days

Question:
12. How is LD expressed?
Answer:
as the number of milligrams of a chemical per kilogram of body weight

Question:
13. Smaller LD50 numbers mean what?
Answer:
more acutely toxic

Question:
14. Subchronic
Answer:
Animals divided into three groups plus a control group. Each group has same number, with equal number
of males/females. Each group fed specified level of toxicant. (One group fed sublethal dose, one group fed
no-effect dose, one group fed intermediate dose, one control group)

Question:
15. Subchronic tests
Answer:
Tests normally run for 90 days, testing what level of exposure has no effects, which organs are
affected/damaged, and the dead animals are autopsied

Question:
16. Chronic testing
Answer:
Tests usually last the average lifespan of test animals

Question:
17. The greater the dose of the toxicant...
Answer:
the greater the effect

, Question:
18. Margin of safety
Answer:
buffer zone between the highest level of exposure assumed safe for humans

Question:
19. What is the arbitrary margin in the US?
Answer:
100 fold

Question:
20. Humans are __________ more susceptible to toxic effects than lab animals
Answer:
10 times

Question:
21. Children are _________ more susceptible to toxic effects than humans
Answer:
10 times

Question:
22. Risk assessment
Answer:
process of determining whether something is an actual threat to human health, estimating how much injury
or harm is likely to result from a given level of exposure and determining if those consequences are serious
enough to warrant action

Question:
23. NOELs
Answer:
No Observed Effect Levels. relationship between levels of exposure and observed human health effects

Question:
24. US EPA and OSHA
Answer:
established in 1970s, began writing rules and regulating environmental health and safety issues

Question:
25. What are some things that the EPA and OSHA control?
Answer:
drinking water, food additives, pesticide residue, air pollution

Question:
26. What does a health risk assessment include?