1

“Tox In” The CityExploring Environmental

Health Science Issues

Student Notes

Name ________________________

Date _________

2

HEADLINES

• Antiperspirants Cause Breast Cancer• Warning: Febreze is Toxic to Pet!• Dioxins Released by Freezing Water Bottles• Chlorinated Water Causes Cancer

What’s a person

supposed to think?

3

Environmental Health -Then & Now

"If you want to learn about the health of a population, look at the air they breath, the water they drink, and the places where they live.“ - Hippocrates, the Father of Medicine, in the Fifth Century BC.

4

What is Environmental Health Science?

Definition:____________________________________________________________________________________________

5

ENVIRONMENT

Environment = ___________ Environment +

____________ Environment +

__________ Environment

6

Sources of Environmental Hazards & Hazards

• Look at the Tox Town Scene for Activity #1

• Identify Potential Sources of Environmental Hazards

• Identify the Potential Hazards associated with each source

7

ENVIRONMENTAL HEALTH SCIENCES

Today, the environmental health sciences aren't entirely about pesticides and other chemical pollutants in our air and water. The definition of "environmental health" has broadened to include the environment we create for ourselves (by smoking or not smoking, and by our diet, for example). It also includes the medicines and other therapies we are prescribed, our occupations and places of work, and our lifestyles: Are we couch potatoes or joggers? Sexually reckless or responsible? Listening to loud music or keeping the volume down?

http://www.niehs.nih.gov/oc/factsheets/ead/healthy.htm

8

9

10

11

                                                                                                                                         

                                        

12

How Does Environmental Health Sciences Differ From How

Humans Affect the Environment (Ecology)?

Activity #2 -Think, Pair, Share

Do Think/Pair/Share Activity

13

Ecology

Ecology -_____________________________

May study how water pollutionis harming _________

14

Environmental Health Science

Focus is on __________ Health

EnvironmentalHealth Scientist

May study how eating the fish is harming __________.

15

Examples of Environmental Hazards that Cause Human Health Problems

• Pesticides/Herbicides• Arsenic• Lead• Mold• Carbon monoxide• Asbestos• Benzene• Electromagnetic Fields

• Alcohol• Radon• Ozone• Particulate Matter• Tobacco• Dioxins• Noise Pollution

16

TOXICITY

• Toxicology

• Toxicity

_________________________________

_________________________________

_________________________________

__________________________________

17

TOXIN

• Toxicant (Poison)—

______________________________________________________________________

18

IS THIS CHEMICAL A TOXIN?

Read Activity #3 Article and Decide

19

IS THIS CHEMICAL A TOXIN?DIHYDROGEN MONOXIDE

The dangers of dihydrogen monoxide include:• Also called "hydroxyl acid", a major component of acid rain;

• Contributes to soil erosion;

• Contributes to the greenhouse effect;

• Accelerates corrosion and breakdown of electrical equipment;

• Excessive ingestion may cause various unpleasant effects;

• Prolonged contact with its solid form results in severe tissue damage;

• Inhalation, even in small quantities, may cause death;

• Its gaseous form may cause severe burns;

• It has been found in the tumors of terminal cancer patients;

• Withdrawal by those addicted to it causes certain death within 168 hrs

Nevertheless, governments and corporations continue using it widely, heedless of its grave dangers.

20

Is This Chemical a Toxin?

Read the news headline onthe next slide:

21

POSTED: Tuesday, May 6, 2003

Plattsburgh, New York--

Police: Student Died From ‘Water Intoxication’ During Hazing

So, is water a toxicant????

The death of a freshman pledging the Psi Epsilon Chi fraternity at the State University of New York College at Plattsburgh has led to 11 members being charged with 150 crimes, including hazing and negligent homicide, at the conclusion of the police investigation. The freshman reportedly died of hydroneutremia, or water intoxication, which caused swelling of the brain.

22

Any chemical can be toxic if you eat, drink, or absorb

too much of it.

23

THE DOSE MAKES THE POISON

“All substances are poisons; there is none that is not a poison.

The right dose differentiates a poisonand a remedy.”

Paracelsus (1493-1541)

24

SOURCE OF EXPOSURE

A hazard’s ________ ___ __________, such as cars, industry, farming, etc.

25

ENVIRONMENTAL PATHWAY

Means of getting from the source to us.

Can include: * air we breath * water we drink * food we eat * soil in which we play and grow food

26

EXPOSURE

EXPOSURE

___________________________________________________________________________________________________

27

ROUTES OF EXPOSURE

_____________

______________ ______________________

__________

28

DOSE

DOSE

-- the term used to describe the specific amount of a chemical that enters the body.

29

DOSAGE

• is the amount of chemical per unit of

body weight.

• usually given as milligrams of chemical

per kilogram of body weight (mg/kg)

DOSE

30

DOSE

Perform Activity #4

31

Effects of Amount on Dose

Increasing the amount of chemical for the same size of organism

Dose increases

32

Effects of Size on Dose

Dose increases

A smaller size of organism with the same amount of chemical

33

DOSE/RESPONSE

Dose Depends on:

DURATIONOF EXPOSURE BODY SIZE

FREQUENCYOF EXPOSURE

34

PROBLEM

Who took the largest dose of Tylenol?

A. An adult woman who weighs 125 lb and took 300 mg of Tylenol

B. An adult man who weighs 180 lb and took 300 mg of Tylenol

C. A teenage boy who weighs 135 lb and took 600 mg of Tylenol

D. A baby who weighs 20 lb and took 100 mg of Tylenol

35

PROBLEM

Who took the largest dose of Tylenol?

Answer: To calculate dose, divide the amount of the hazard by the body weight

The concentration of the chemical in the small body is much higher than in the larger bodies.

A. 300mg/125lb= mg/lbB. 300mg/180lb= mg/lbC. 600mg/135lb= mg/lb

D. 100mg/20lb= mg/lb5.0

2.41.7

4.4

36

What amount causes harm?

Some chemicals are good in small amounts, but toxic in large amounts

Example: botulinum toxin

Small amount →

Large amount →

37

What amount causes harm?

Some chemicals are good in small amounts, but toxic in large amounts

Example: botulinum toxin

Small amount → prevents wrinkles (BOTOX)

Large amount → paralysis, death

38

TOXIC EFFECTS

TOXICANT TOXICITY

Sugar

Salt

Herbicide

Arsenic

Nicotine

Botulism

Rank the following in order of least toxic (1) to most toxic (6) based on LD50 data:

39

TOXIC EFFECTS

TOXICANT TOXICITY

Sugar 1

Salt 2

Herbicide 3

Arsenic 4

Nicotine 5

Botulism 6

Rank the following in order of least toxic (1) to most toxic (6) based on LD50 data:

40

TOXIC EFFECTS

Chemical Lethal Dose

Sugar 3 quarts

Alcohol (ethyl alcohol) 3 quarts

Salt (sodium chloride) 1 quart

Herbicide (2,4-D) ½ cup

Arsenic (arsenic acid) 1-2 teaspoons

Nicotine ½ teaspoon

Food poison (botulism) microscopic

Approximate Lethal Doses of Common Chemicals(Calculated for a 160 lb. human based on data on rats)

Source: NIH Curriculum, Chemicals, the Environment, and You Videodiscovery, 2000

41

TOXIC EFFECTS

Terms used to refer different durations of exposure:

ACUTE EXPOSURE

CHRONICEXPOSURE

42

TOXIC EFFECTS

Terms used to refer different durations of exposure:

ACUTE EXPOSURE

CHRONICEXPOSURE

Refers to single exposure or a very limited exposure

Example: breathing fumes from chlorine spill

Refers to a prolonged or repeated exposure

Example: breathing polluted air over a lifetime

43

INDIVIDUAL SUSCEPTIBILITY

Why did I get sick and she didn’t?Depends on:

44

INDIVIDUAL SUSCEPTIBILITY

Why did I get sick and she didn’t?Depends on:

GENETICS

GENDER

AGE BODY SIZE

GENERAL HEALTH

45

PROBLEM

A family has a clogged furnace that is producing carbon monoxide, a hazardous gas. Which family member is likely to be harmed the most?

A. Nicholas, the son who is in 12th grade

B. Baby Quianna, who is going into preschool next year

C. Mrs. Shaw, the mother who works at home

D. Mr. Shaw, the father who works at the local book store

46

Dose depends on several factors. Here we can estimate: * length of exposure, * age of the people exposed, and * size of the people exposed. It is most likely that Baby Quianna is most likely to be harmed as: 1) she is the youngest and therefore 2) the smallest, and 3) spends the most time in the home along with her mother.

ANSWER:

47

RISKS and BENEFITS

Carousel Activity

48

RISKS and BENEFITS