1. 2/8 A/B Day
LEQ: What are the risks and benefits of
using chemicals?
1. What is a dose?
2. What is exposure?
3. What is potency?
4. Why will some people get sick and others will not—
even when they are exposed to the same amount of a
chemical?
5. Copy and complete: The concentration of a
chemical [increases/decreases] at the top of the food
chain.

2. Let’s Practice: Fill in the blank!
Beginning in the 1950’s, scientists started spraying large
DOSES
_________ of DDT into the environment. DDT is a chemical
with a very high POTENCY meaning it is extremely powerful,
________,
even in small amounts. As humans continued to spray DDT
into the environment, we quickly learned that the
_______________ of the chemical increased as it traveled
CONCENTRATION
higher up the food chain. Small organisms, like insects,
would only have a small percentage of DDT in their bodies,
but the organisms at the top of the food chain would eat
millions of smaller animals, which would greatly increase the
amount of the chemicals in their bodies. Organisms
EXPOSURE to the chemical continued to increase because the
________
chemical did not disappear once it was sprayed into the
environment. Because different organisms have a different
SUSCEPTIBILITY
______________ to the chemical, not all of the eagles died.

3. EOG QUESTION
Which factor best explains why some people
will develop cancer and others will not after
being exposed to the same high levels of a
harmful chemical?
a) concentration of the chemical
b) potency of the chemical
c) individual susceptibility to the chemical
d) individual exposure to the chemical

4. Today’s LEQ: What are the risks and
benefits of using chemicals?
By the end of today, you should be able to…
1. Make a risk-benefit analysis for using chemicals for
medicine, sanitation, food preservatives, and
agriculture

5. Focus Vocabulary
102. Sanitation
103. Preservatives
104. Oxidation
105. Fertilizer
106. Pesticide

6. Activating Strategy:
http://www.youtube.com/watch?v=R7gtBXMyM
I0&feature=related

7. Think-Pair-Share: For $50,000, would you…
Eat a live scorpion?
Be covered in
live snakes?
Jump off a skyscraper?

8. You just did a ….
Risk-Benefit Analysis
What are the risks?
What are the benefits?
Is it WORTH IT?!

9. Using
Chemicals:
RISKS AND
BENEFITS

10. Chemicals Used Benefits Risks
Sanitation
Preservatives
Medicine
Agriculture

11. Chemicals Used Benefits Risks
Sanitation
UNSCRAMBLE
THE
Preservatives
FOLLOWING
HERE BY
Medicine PUTTING THE
INFORMATION
NEXT TO THE
APPROPRIATE
Agriculture
TERM!

12. SANITATION: Check your work!
-the use of chemicals to remove or treat waste
-the use of chlorine to filter dangerous material from drinking water
Preservatives:
-the use chemicals to preserve food and keep it safe to eat
-chemicals slow oxidation, which causes foods (such as apples) to turn
brown
MEDICINE
- the use of chemicals to treat sickness and pain
-chemicals are used to create antibiotics, which kill disease-causing
bacteria
AGRICULTURE
-the use of fertilizers, which give plants nutrients to help them grow
-the use of chemicals such as pesticides, which kill organisms (like
insects) that eat crops

13. Chemicals Used Benefits Risks
Sanitation
UNSCRAMBLE THE
Preservatives
FOLLOWING HERE
BY PUTTING THE
INFORMATION NEXT
Medicine TO THE APPROPRIATE
TERM!
Agriculture

14. Risk-Benefit Analysis: Sanitation
-chlorine can cause water to taste
and smell bad
-Treating drinking water removes
harmful bacteria

15. Risk-Benefit Analysis: Preservatives
-keeps food safe to eat for a long
time
-some people are allergic or
intolerant to preservatives, which
can make them sick

16. Risk-Benefit Analysis: Medicine
-bacteria can adapt to the
medicine and come back stronger
than before
-cures illness and stops spread of
disease

17. Risk-Benefit Analysis: Agriculture
-helps us increase the amount of
crops we can produce
-can act as carcinogens (cause cancer)
-can destroy ecosystems by causing
over-growth or killing animals in the
food chain

18. EOG QUESTION
What makes fertilizers a benefit to the farming
industry?
a) they increase nutrients in the soil
b) they increase the growth of helpful
bacteria
c) they decrease the chance of bacteria
growing in the soil
d) they decrease the chance of plants
being eaten by insects

19. EOG QUESTION
What is the best way to reduce a person’s
exposure to pesticides??
a) put leftovers in the refrigerator
b) do not eat bread with mold on it
c) make sure meat is cooked all the way
before eating it
d) wash fruits and vegetables before eating
them

20. EOG QUESTION
Why were some pesticides, such as DDT,
removed from public use?
a) they can cause heart disease
b) they can cause diabetes
c) they can cause meningitis
d) they can cause cancer

21. Make an advertisement!
On your paper, make an advertisement for a type of
medicine, pesticide, fertilizer, food preservative, or a
new sanitation chemical.
Your advertisement MUST INCLUDE:
-the name of your product
-a description of what it does
BE CREATIVE! Think
-the benefits of using it about what a real
-the risks of using it advertisement looks
like and what it
-illustrations includes!

22. Summarizer:
1. What is one risk of using preservatives in
food?
2. What are the benefits of using chemicals for
sanitation?
3. Do you think that using pesticides to grow
crops is worth the risk of damaging our
environment?
4. Why or why not (for # 3)