Toxicology

10/26 Chapter 8: Toxicology Powerpoint

Chapter 8 quiz for Wednesday and Thursday

Daily Work Opportunities This Week:

Chapter 8 Case Study
Chapter 8 notes
Chapter quiz
Trouble Waters video worksheet and the link to the video, Strange Days on Planet Earth: Troubled Waters

Project grade

Toxicology Lab

1. Describe environmental health as it relates to diseases that affect humans.

2. Explain the types, origins, and effects of various toxins.

3. Understand the difference between bioaccumulation and biomagnification.

4. Describe synergism and the implications of water soluble vs. fat soluble

substances with relation to toxicity.

5. Explain how to measure toxicity and the meaning of acute and chronic effects of

toxins.

6. Applications of risk and risk assessment using cost/benefit analysis 

7. How do people contract malaria? What was the disease vector? Is this a chronic or an acute condition? Why? Could this illness have been prevented?How?

 

 

8. Why does every human have some persistent organic pollutants (POPs) in

his/her body? How might these chemicals have gotten there? Where are these chemicals most likely to be stored in the body? Why? How might the chemicals affect our health? Is this a chronic or an acute exposure?
 

9. How do toxins biomagnify and which animals are most affected?

 

 

10. What is sick building syndrome? What are the symptoms of sick building syndrome?

 

 

11. In toxicity testing, what is LD50?

Practice Questions

  

Multiple Choice:

Directions for questions 1-5: The lettered choices below correspond to the

descriptions given in questions 1-5. Select the one lettered choice that best fits
each statement. Each choice may be used once, more than once, or not at all.

(A) endocrine disruptors

(B) mutagens
(C) teratogens
(D) carcinogens
(E) allergens

1. formaldehyde and PCBs

2. thalidomide and alcohol
3. smoke from cigarettes and sun overexposure
4. causes abnormalities during embryonic growth
5. BPA and dioxin

6. The SARS disease has been reported to have started with

(A) mosquitos carrying the virus
(B) Asian chicken markets
(C) monkeys imported from South America
(D) crows from the Mid-western United States
(E) exotic birds imported from Central America

7. All of the following are reason why parasites and diseases are spreading into

new area except
(A) increase in ocean temperatures
(B) increase in precipitation
(C) increase in the range of a species
(D) decrease in tundra temperatures
(E) increase in tolerance to insecticides

Use the following description for questions 8-10.

In a small pond it has been observed that phytoplankton are eaten by minnows.

The minnows are a food source of a small mouth bass. The small mouth bass is
one of the favorite foods of an eagle. Nearby, a fruit orchard uses pesticides to
eliminate a beetle that eats their fruit. A stream runs through the orchard and
empties into the pond.

8. Which of the following organisms will contain the highest amount of pesticide

in their body?
(A) beetles
(B) minnows
(C) phytoplankton
(D) small mouth bass
(E) eagle

9. Identify the phenomenon responsible for the result in question number 8.

(A) biomagnification
(B) LD50
(C) food chain result
(D) pesticide build-up
(E) bioillumination

10. Identify the process that causes the pesticide to accumulate in the pond.

(A) The carbon cycle carries the pesticide to the pond
(B) The pesticide travels to the pond by the nitrogen cycle
(C) Run-off of pesticide into the stream when it rains
(D) The phytoplankton change the pesticide into nutrients for the minnows
(E) The water from the pond changes nutrients in the pond to pesticides

Free-Response Question:

Directions: Answer all parts of the following question. Where explanation or

discussion is required, support your answers with relevant information and/or

specific examples. When a calculation is required, be sure to show how you

arrived at your answer.

1. An experiment was performed to test the toxicity of atrazine using brine

shrimp and the following data was collected.

Dose % Mortality

0.01 mg/L 5

0.10 mg/L 5
0.20 mg/L 10
0.30 mg/L 40
0.40 mg/L 70
0.50 mg/L 90
0.60 mg/L 100
0.70 mg/L 100
0.80 mg/L 100

(a) Graph the data. Use a sigmoid shaped curve to connect the points.

(b) From the graph:

(i) Determine the LD50.
(ii) Explain the meaning of LD50.
(iii) On the graph, label the threshold level of toxicity.
(iv) Define the threshold level of toxic.

(c) Can these results tell you about the possible toxicity of atrazine to humans? Explain your answer.

(d) It was found when atrazine was combined with another toxic substance the results of the LD50 experiment was much greater than the two substances combined. What is this called? Explain how this happens.