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by
Holly S. Anthony
The student population that I will be targeting for this curriculum will be my Chemistry and Earth Science classes. These students might already have a minimal basis of environmental science, but through this unit they can extend their knowledge of specific environmental pollutants, causes, effects, and solutions. At my school, the student / teacher ratio for these classes is approximately 10:1, therefore; a considerable amount of individual attention may be given for each student. This concentrated focus on each student’s comprehension and performance of discussions, labs, essays, and investigations will allow me to expand on certain topics that are of special interest to the student. Also, each student’s working pace can vary depending on the activity she is doing. This will permit some students to stay on one topic for an extended period of time, or to move ahead to another topic of particular choice.
The following represent environmental topics to be discussed:
The full extent of environmental contamination by pesticides is not known. Yet what we are finding out is alarming. Between 1982 and 1985 the FDA detected pesticide residues in 48 percent of the fresh vegetables and fruits we eat most frequently. In addition, according to the EPA estimates, pesticides have contaminated ground water in approximately 38 states, fouling the drinking water of half of all Americans. Estimates of some 6,000 cases of cancer a year are thought to be caused by most of the one-third approved pesticides in use today that have been tested. Most of the 50,000 pesticides on the market have never been tested for long-term effects. Finally, there is mounting evidence that farmers, farmworkers, and their families who are exposed to pesticides and herbicides have a far greater risk than the general population of developing leukemia and other cancers, birth defects, and diseases of the central nervous system. (Naar, 1990)
In 1962 Rachel Carson alerted the world of the devastating effects of DDT on birds, fish and other animals. Although banned in the United States, DDT is still shipped here after being manufactured in Western Europe. It is also exported to many countries such as Mexico and Columbia from whom we import large quantities of food and coffee. DDT residues were first found in human tisues including blood and the liver, kidney, heart, and central nervous system in 1944. Although 80% of pesticides are used in the industrialized nations, 99% or more of the deaths from pesticides occur in low-income nations, where safety precautions such as label instructions, protective clothing, and field reentry intervals are less likely to be employed. (Wargo, 1996) Additionally, DDT and other pesticides are very persistent and mobile in the environment, having been found in animals in the Antarctic and other areas never sprayed. Another consequence of the widespread and long-term use of pesticides, herbicides, and fungicides is that pests, weeds, and fungi are becoming resistant to the chemicals. This calls for even greater amounts being used in a never-ending cycle of poison. (Naar, 1990)
Some ways to get pesticides out of your food or to prevent extensive use of pesticides are as follows:
a. Apply bugs that act as pest killers for harmful insects.
b. Grow your own food organically based on the principles of using compost to create a fertile soil.
c. Buy organic food at health food stores and farmers’ markets.
d. Wash all produce in clean water or a weak solution of hydrogen peroxide.
e. Peel, scrape, or remove skins from fruits and vegetables.
f. Buy local, buy in season to get fresher and less irradiated food.
g. Beware the perfect apples that can contain harmful pesticides. This example of a cosmetic standard normally encourages pesticide use for other fruits and vegetables. (Naar, 1990)
Table 1
| Organism | Pesticide concentration |
| Blue-green algae | 0.0001 |
| Water crustaceans | 0.001 |
| Small fish | 0.01 |
| Trout | 0.1 |
| Polar bears | ? |
blue-green algae ——> water crustaceans ——> small fish ——> trout —> polar bears
____a. Pesticide concentration decreases.
- 1. What can one conclude about the concentration of pesticides in the organisms as one moves up the food chain?
____b. Pesticide concentration remains fairly constant.
____c. Pesticide concentration increases about ten times between each link.
____d. Pesticide concentration initially increases but then decreases.
____a. 0.01 ppm
- 2. If the pattern of change in the concentration of the pesticide seen in earlier links continues, what would most likely be the concentration of the pesticide in polar bears?
____b. 0.1 ppm
____c. 1.0 ppm
____d. 10.0 ppm
____a. Blue-green algae
- 3. Which organism serves as the primary producer in the food chain shown in Figure 1?
____b. Water crustaceans
____c. Small fish
____d. Trout
____a. The pesticides killed off the insects food supply in the past.
- 4. Some pesticides are not as effective against insects as they were in the past. Which of the following best explains why this is true?
____b. The pesticides were used in lower concentrations in the past.
____c. Individual insects became tolerant to the pesticides and survived.
____d. Some of the insects were tolerant to the pesticide and survived to produce offspring.
- 5. Suppose the small fish population was killed off by the pesticides. Describe what would happen to the rest of the organisms in the food chain shown in Figure 1. Explain your answer fully.
How can you find out if your water is safe? Here is how you can find out what your own situation may be at home:
What can you do to reduce contaminants in your drinking water? Here are some easy tips to help. First, let cold water run for at least three minutes before using. Even for hot beverages and infant formulas, draw cold water because hot water dissolves lead and copper more readily. Second, use cold water primarily and let it boil for 20 minutes or whip the water for 15 minutes in a blender with the top off to get rid of bacteria and chemicals. Third, add a pinch of powdered vitamin C to a glass of water just before drinking to lower chlorine’s effects. Fourth, buy a purifier to disinfect water. And lastly, use a filter to screen water. (Naar, 1990)
- a. Look for the signs of orange-red or brown color in water or the sink resulting from iron by rusting pipes. A greenish stain could mean copper rust.
- b. A foamy appearance could be detergent residue.
- c. Cloudy water might indicate minerals, heavy metals, or other contaminants.
- d. Sniff the water to detect an odor of rotten eggs indicating sulfur or decaying bacteria. Candylike aroma might be vinyl chloride or other chemicals. Gasoline or oil smell could be caused by a defective water pump. Swimming pool odor is probably pointing to too much chlorine.
- e. Get the water tested for drinking-water quality including criteria of coliform bacteria count, hardness / softness, heavy metals, pesticides, herbicides, fungicides, and other chemicals. (Naar, 1990)
Energy sources that are not fossil fuels are called alternative energy sources. Wind, water, and sunlight are nonpolluting renewable energy sources. Windmills and waterwheels played important roles in early industries. Currently, in the United States, these energy sources account for only about 4% of the electricity produced. (Globe, 1993) Many scientists hope that technology will lend itself to us to be able to use renewable energy sources more frequently and more efficiently, so that we are not without alternatives as our nonrenewable resources become depleted.
While many of these outdoor contaminants may seem to be minor irritants, they become a real and present danger when added together and concentrated within four walls over a long period of time we spend indoor. Some specific causes of indoor air pollution are as follows:
What can you do about indoor air pollution? You can significantly lower the concentrations of air pollution in your own home by increasing the circulation between outdoors and indoors. Opening windows and doors increases the natural ventilation rate. Turning on kitchen, bathroom or workshop exhaust fans is a simple way to remove contaminants from those areas. Buying a heat-recovery ventilator or air cleaner could also exchange and clean air in your home. Although air conditioners and humidifiers often harbor harmful bacteria, mold, fungi, and viruses that are spread into the air, cleaning these instruments can help. Air conditioners should be professionally changed or cleaned at least once a year, depending on how much use they get. Humidifiers should be cleaned every day with a strong solution of white vinegar and very hot water. One added hint to keeping air clean is to buy common houseplants. Some houseplants have a natural ability to rid the air of harmful pollutants. To clean the air in a typical 1,500-square foot house 15 to 20 plants would probably be adequate. (Naar, 1990)
- a. Burning of wood, coal, and kerosene in such places as stoves, furnaces, and heaters.
- b. Use of aerosol cleaners and disinfectants.
- c. Ammonia.
- d. Air fresheners.
- e. Insect sprays.
- f. Cigarette smoke.
- g. Asbestos, lead, and radon in many building materials, finishes, and furnishings. (Naar, 1990)
Below is a list of questions that can be answered after “Share Your Ride” activity:
- 1. When your ride is shared with two others at 9.7 cents / mile / person, what is the savings monthly? yearly?
- 2. When your ride is on a bus after you purchased a monthly bus ticket for $100.00, what is the savings monthly? yearly?
- 3. When your ride is on a train after you purchased a monthly train ticked for $79.00, what is the savings monthly? yearly?
- 4. What are the following pounds of pollutant / person / year created by a car with a single occupant at 1200 miles / month:
- ____a. carbon monoxide
- ____b. nitrogen dioxide
- ____c. other chemicals
- ____d. total
- 5. What are the following pounds of pollutant / person / year created by a car with a three occupants at 1200 miles / month:
- ____a. carbon monoxide
- ____b. nitrogen dioxide
- ____c. other chemicals
- ____d. total
- 6. What are the following pounds of pollutant / person / year created by a van with eight occupants at 1200 miles / month:
- ____a. carbon monoxide
- ____b. nitrogen dioxide
- ____c. other chemicals
- ____d. total
- 7. What have your calculations shown?
- 8. Imagine a situation twenty years into the future, where 50% of the population uses mass transit. Describe how this dramatic reduction in pollutants entering the atmosphere would affect the environment.
Although carbon monoxide travels to the blood via the lungs, only about one half of it is absorbed by the blood, but the amounts which cause severe poisoning are of the order .1-.3%, therefore only a very small quantity is needed for damage. Studies have been conducted to determine human’s revival and recovery time after exposure to high levels carbon monoxide. These studies have shown that in a matter of minutes, carbon monoxide poisoning can occur. (Bokonjic, 1963)
It has been estimated that the concentrations of carbon monoxide in parking garages are very high, usually exceeding the federal standard level of 35 ppm / 30 minutes. (Duan, 1988) Some ways to protect ourselves against carbon monoxide poisoning are by the following: Do not use gas-powered small devices or tools indoors. Try to use tools with electricity or compressed air. Check your oven for blue shaped flames, not irregular, lazy and yellow flames. Do not use an unvented gas heater in a bedroom. Check fireplace drafts, gas appliances, and chimney vents for defects yearly. Patch all vent pipes with gum or tape. Have the cooling unit of a gas refrigerator checked if it gives off an odor. Do not used charcoal grills or portable gas camp stoves indoors. Check your exhaust system of your car periodically. Do not run your automobile in the garage with the doors shut. (Center for Disease Control & National Center for Environmental Health, 1997)
Studies have shown that the most significant factor in determining radon concentration was the geographical region, followed by the soil type, year of building construction, and type of building foundation. The lower figure represents a house with a basement, built in 1950’s on clay soil. The higher figure represents a house with a concrete slab in contact with the ground, built in the 1980’s on gravel. (Makelainen, 1990) This study shows that certain geographical regions and soil types with abundant granite, shale, and certain phosphates can have a high radon concentration. It also shows that houses built in 1950’s were usually less air tight which allowed a higher air exchange rate to get rid of radon gas. Additionally, a concrete slab foundation in contact with the ground will allow for more detrimental filtering of the radon gas.
Blood tests on individuals may be done in order to detect lead poisoning. If a blood level of an individual ranges from 10-19 micrograms of lead per 1 deciliter of blood, follow-up and repeat screening will need to be done. A blood level at approximately 20 micrograms of lead per 1 deciliter of blood indicates lead poisoning and requires treatment. A blood level at approximately 70 micrograms of lead per 1 deciliter of blood indicates a serious case of lead poisoning and requires chelation. (Childhood Lead Poisoning Program, 1997)
The symptoms of lead poisoning may appear in various forms. Acute lead encephalopathy may result in coma, seizures, apathy, incoordination, alternate states of consciousness, or loss of skills. Severe and permanent brain damage may result in 70-80% of children infected. Symptomatic lead poisoning may result in decreasing in play activities, lethargy, anorexia, vomiting, intermittent abdominal pain, or constipation. These two forms of lead poisoning require a blood test to determine the exact concentration of lead in the blood. (Childhood Lead Poisoning Program, 1997)
Some agents to treat lead poisoning are Bal in Oil, Curpimine, Chemet, and CaNa EDTA. The CaNa EDTA Chelation Test requires the patient to empty his / her bladder and be infused with this chemical at 500 mg/m in 5% dextrose over 1 hour. If caught early enough, these cases of poisoning can be treated sufficiently. (Childhood Lead Poisoning Program, 1997)
What can you do to prevent or decrease lead poisoning in your home? First of all, one common mistake in ridding of lead paint in the home is to chip away at it and dispose of all pieces. This is not as easy as it seems. As you begin to chip at the paint, small lead dust particles enter the air and can make their way to your airways and lungs. This can cause a worse scenario than before. In order to properly get rid of lead paint, trained professionals need to do the job with ventilated masks and technical equipment. Other approaches you can take in your home include using a wet mop approximately twice a week. This prevents lead dust from accumulating. Also, you should use cleaners high in phosphates to prevent lead poisoning. Remember that most homes built prior to 1970 did use lead paints on walls and especially window sills. If you feel your house could have lead build-up, have it examined by a professional or call the LEAD HOTLINE at 1-800-424-LEAD.
Toxic waste disposal is being implemented in most areas, but the methods contain flaws. The main disposal methods are as follows:
Some health effects of toxic chemicals include swelling of tissues in the upper respiratory tract, depression of the central nervous system, irritation, and stripping naturally protective oils from skin, lung tissue, or eyes. Other effects are damaging cells, and chronic effects on the liver, kidneys, and heart. In addition, most of the chemicals mentioned are suspected of causing cancer. (Naar, 1990)
- a. Dumping in pits, ponds, and lagoons. This is the cheapest and least regulated method, any many sites are illegal.
- b. Landfills fitted with liners of clay and plastic. They have the potential of leaching toxic substances into ground, water, and sewers.
- c. Above-ground storage by tanks or sheds. These present the danger of fire or explosion.
- d. Incineration where combustion is used to destroy toxic materials. This produces air pollution and residual ash.
- e. Underground deep wells. A concern of the impact of earthquakes. (Naar, 1990)
What can you do about toxic chemicals? First, realize that although it may not seem important if you pour a can of old bleach or turpentine down the sink or toilet, imagine our country’s total dumping. For example, if you mulitply your one can by 83 million other houseuholds in the United States, each one of which contains an estimated 3 to 8 gallons of hazardous waste, it certainly adds up. Therefore, clean up your own mess in the proper fashion. Also, contact the EPA and your local toxic waste facility for specific information on removal of toxic wastes. (Naar, 1990)
Materials for each pair of students:
| -3 buckets | -baking soda | -water |
| -cornstarch | -soap flakes | -white vinegar |
| -stirrer | -rags or paper towels | -all-purpose cleaning liquid |
Procedure:
- 1. Make a nontoxic all-purpose cleaning liquid in a bucket. Add 1 tablespoon (15 mL) of baking soda and 1/4 cup (60 mL) of soap flakes to 1 gallon (3.8 L) of hot water. Stir well.
- 2. Wet the sponge with the homemade cleaning liquid, then clean a dirty desktop. Rinse the sponge thoroughly with clean tap water.
- 3. Use the store-bought cleaner to clean another dirty surface.
- 4. Make a nontoxic glass cleaner in another bucket. Add 2 tablespoons (30 mL) of cornstarch and 1/2 cup (120 mL) of white vinegar to 1 gallon (3.8 L) of warm water. Stir.
- 5. Moisten a rag or paper towel with the homemade glass cleaner. Clean a dirty window.
- 6. Use the store-bought cleaner to clean a dirty window.
Questions:
- 1. Which does a better job of cleaning a desktop, the homemade cleaner or the store-bought kind? Which does a better job of cleaning the window?
- 2. Do any of the cleaners have an unpleasant odor? Which cleaning fluid has the most unpleasant odor and which one has the least unpleasant odor?
- 3. Do any of the cleaners irritate your hands or eyes? Rate the cleaners for irritation.
- 4. Was it time consuming or inconvenient to mix up either of the homemade cleaners? Explain your answer.
- 5. Compare the ingredients in your homemade cleaners to the ingredients on the store-bought cleaners. What seems to be the biggest difference between them?
- 6. Which products do you think would be less harmful to the environment, the store-bought cleaners or the homemade kinds?
- 7. How do you think most people dispose of cleaning products after they have finished using them? What effect would disposing of cleaners in this way have on the environment?
In summary, with this activity, students will be given various statistics of buildings, concentrations of possible pollutants, and information on products or procedures in the building that could cause pollution. The class needs to identify the pollutants that are causing problems, where specifically in the building are the problems, can the pollutants spread, if so how and where, what are possible consequences of these pollutants, are they mild or serious, and what methodology would they use to remediate the problems? With this activity, students will be measuring and converting scientific measurements using ppm, ppb, mcg, pCi, and forms of area and volume, and they will get practice in an interdisciplinary activity requiring mathematics and scientific skills. Additionally, students will need to use problem-solving techniques in order to determine cause and effect and to develop solutions based on observation and experimentation. This allows the students to work at their own pace and to use their own knowledge to approach a problem from different angles. Furthermore, as the class writes up a lab report from their findings, they will need to present it professionally as they are acting as environmental inspectors. This written report and oral presentation combine the language arts skills and scientific skills to make another interdisciplinary activity.
STANDARDS FOR MAJOR POLLUTION FOR AIR AND DRINKING WATER (SOURCE: U.S. EPA, 1993)
| 1. OZONE | 220 ppb for 30 minutes |
| 2. CARBON MONOXIDE | 35 ppm for 30 minutes |
| (levels as high as 50-100 ppm have been detected in traffic jams or on freeways during rush hours) | |
| 3. AIRBORNE PARTICULATES- | 150 mcg / m for 24 hours |
| 4. NITROGEN DIOXIDE | 53 ppm for 1 year |
| 5. SULFUR DIOXIDE | 330 ppm for 1 year |
| 140 ppm for 24 hours | |
| 6. LEAD | 1.5 mcg / m for 3 months |
| 200 mcg / m for floors | |
| 500 mcg / m for window sills | |
| .05 mg / L in primary drinking water | |
| 10-19 mcg / dL in blood = caution and further screening | |
| 20 mcg / dL in blood = lead poisoning | |
| above 70 mcg / dL in blood = serious lead poisoning requiring chelation treatment | |
| 7. CHLORIDE | 250 mg / L |
| 8. COPPER | 1 mg / L |
| 9. ZINC | 5 mg / L |
| 10. FLUORIDE | 2 mg / L |
| 11. IRON | 0.3 mg / L |
| 12. MANGANESE | 0.05 mg / L |
| 13. MERCURY | 0.002 mg / L |
| 14. ARSENIC | 0.05 mg / L |
| 15. BARIUM | 1 mg / L |
| 16. CADMIUM | 0.01 mg / L |
| 17. CHROMIUM | 0.05 mg / L |
| 18. TOTAL COLIFORMS | 1 per 100 mm |
| 19. RADON | 4 pCi / L = guidance level which requires a thorough inspection |
| 20. HYDROCARBONS | 5 ppb in drinking water |
| 21. DISSOLVED SOLIDS | 0-60 mg / L = soft water |
| 61-120 mg / L = average water | |
| 121-180 mg / L = hard water |
2. Bokonjic, Nenad “Stagnant Anoxia and Carbon Monoxide Poisoning” 1963.
3. Burns, J. William (CT Department of Transportation) and Holbrook, Sidney J. (CT Department of Environmental Protection) “ What’s up with Air Pollution? What Can I Do about It?” 1995.
4. Carson, Rachel “Silent Spring” 1962.
5. Center for Disease Control (public pamphlets) 1997.
6. Childhood Lead Poisoning Program (public pamphlets) 1997.
7. Cole, Leonard A. “Element of Risk: The Politics of Radon” 1993.
8. Cothern, C. Richard and Rebers, Paul A. “ Radon, Radium, and Uranium in Drinking Water” 1990.
9. Cross, Fredrick T. “ Indoor Radon and Lung Cancer: Reality or Myth?” 1990.
10. Duaan, Naihan et al. “ Comparison of Microenvironment Monitoring with Personal Monitoring in Estimating Population Exposure to Carbon Monoxide” 1988.
11. Ehrlich, Paul R. and Anne H. “Healing the Planet” 1991.
12. Globe Book Company “Science, Technology, & Society : Impacts of Technology” 1993.
13. Harr, Jonathan “Civil Action” 1996.
14. Information Plus “ Water, No Longer Taken for Granted” 1993.
15. Jacobs, B. “Technical Bulletins” (developed for Maryland State Department of Education, Division of Business Services, School Facilities Branch, 200 West Baltimore Street, Baltimore, Maryland, 21201) 1995.
16. LaMotte Company “ Tap Water Tour” (hands-on test kit and mini curriculum) 1996.
17. Makelainen, I. et al. “Prediction of Indoor Radon Concentrations Based on Residence Location and Construction” 1990.
18. Naar, J. “ Design for a Livable Planet” 1990.
19. National Association of Physicians for the Environment (N.A.P.E.) Conference Summary. http. / www.intr.net / napenet / airsum. html thron 1993.
20. National Center for Environmental Health (public pamphlets) 1997.
21. Needleman, H. and Landrigan, P. “Raising Children Toxic Free” 1995.
22. Roan, Sharon L. “Ozone Crisis” 1989.
23. The Oryx Press “Environmental Hazards to Young Children” 1985.
24. UNICEF: “State of the World’s Children” 1997.
25. Wargo, John “Our Children’s Toxic Legacy” 1996.
2. Chemistry : A Modern Course (textbook for chemistry classes) 1990.
3. Chemistry : Visualizing Matter (textbook for chemistry classes) 1996.
4. Globe Book Company “Science, Technology, & Society : Impacts of Technology” 1993.
5. Naar, J. “ Design for a Livable Planet” 1990.
6. Needleman, H. and Landrigan, P. “Raising Children Toxic Free” 1995.
2. motor oil
3. coal
4. graduated cylinders
5. beakers
6. calculators
7. balance beams
8. Carbon monoxide detector device
9. Radon detector device
10. buckets
11. baking soda
12. cornstarch
13. soap flakes
14. white vinegar
15. stirrers
16. rags or paper towels
17. all-purpose cleaning liquid
Contents of 1997 Volume VII | Directory of Volumes | Index | Yale-New Haven Teachers Institute
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