Pollution

1. Pop cans on lawn in front of school.

2. Smokestacks.

3. Phone lines

4. Motor Vehicles

5. Microwave Oven

1. Pop cans are almost entirely made out of aluminum.

§ Aluminum is very reactive.

§ Forms an oxide coating- resistant to corrosion.

§ Body of can is alloyed with small amount of Manganese to improve strength and workability.

§ Takes up lots of landfill space.

§ Energy required to make, collect, & recycle them.

§ Refined from Bauxite- Bauxite mining has impact on the environment.

2. Carbon Dioxide, Sulfur Dioxide and other types of contaminants pouring from industrial smoke stacks contributes largely to world's atmospheric pollution. CO2 contributes significantly to global warming, while SO2 emissions are principal cause of acid rain in N.E. United States, S.E. Canada, and E. Europe.

3. Power lines generate electromagnetic fields and are a source of extremely low frequencies (E.L.F.)

§ Extremely low frequencies are associated with man-made sources, whereas, electromagnetic fields are associated with both natural and man-made sources.

§ There is no evidence that extremely low frequency magnetic fields cause cancer in animals.

§ Evidence that there is a link between childhood leukemia and E.L.F.s are inconclusive.

§ Studies done to show a link between childhood brain tumors or cancers were not consistent because the studies were small and of low quality.

§ The studies done to show a link between residential exposure to E.L.F. s and magnetic fields included use of appliances are sparse and methodologically limited.

§ The studies done to show a link between occupational exposure to E.L.F.s and adult cancers were not consistent and didn't show any association with any particular malignancy.

4. Concern by consumers has been caused by isolated reports that suggest that microwave heating produces chemical changes in foods with formation of potentially toxic compounds. In 1989, the Lancet, a reputable journal published a letter by a group of experts which concluded that the results obtained in the experiment were not relevant to the way food is prepared and consumed. A second more recent report in a Swiss journal appears to be irrelevant to the domestic use of microwave ovens.

§ Food cooked in a microwave oven does not heat uniformly and unwanted microorganisms may survive in portions of poorly heated food. Manu- facturers use stir fans and turntables and recommended standing times to help alleviate the problem of uneven heating.

§ Microwave ovens are less likely to cause burns than are conventional ovens. However, the potential hazard of burns associated with microwave cooking is not often considered, and many people allow young children to operate these appliances unsupervised

§ Only utensils designed for the purpose should be used in a microwave oven.

§ Some additives used in manufacturing of plastics, particularly those that make it pliable, may migrate into food, especially at high temperatures. Only those plastic containers, which have been designed for microwave cooking, should be used, and thrown out when signs of breakdown occur.

§ Plastic films that are used in microwave ovens are not to come in direct con- tact with the food they cover. Meals to be reheated on a plate may be covered with white absorbent kitchen paper to prevent spatter.

§ Migration is likely to occur in hot fatty foods so glass containers are preferred to plastic for heating them.

§ The packaging industry recognizes the problems of potential migration from packaging into food and constantly monitors and improves manufacturing processes.

Old or faulty door seals are the most common causes of microwave leakage. Mechanical abuse, dirt buildup, or simple wear and tear of continued use can cause door seals to be less effective. Theoretically, there would be minute amounts leaking through viewing glass but measurements have shown this to be insignificant.

Biological effects of microwave radiation usually occur with pulsed or pulse-modulated fields and not with continuous wave fields allied with microwave ovens.

The power density of microwave radiation decreases rapidly with increased distance from oven. The farther away from the oven you stand, the less radiation you will be exposed to.

5. Emissions from an individual automobile are generally low relative to the smokestack image people associate with air pollution. It's the emissions from thousands of vehicles that add up.

Usual exhaust pollutants are:

Hydrocarbons- result when fuel molecules in engine do not burn or burn partially.

Nitrogen oxides- under high pressure and temperature conditions in an engine, nitrogen and oxygen atoms in the air react to form various nitrogen oxides. Pre- cursors to ozone.

Carbon Monoxide- is a product of incomplete combustion. Occurs when Carbon in the fuel is partially oxidized rather than fully oxidized to Carbon Dioxide (CO2).

Carbon Dioxide- now considered a pollution concern. A "green house" gas traps the earth's heat and contributes to the potential for global warming.

Hydrocarbon pollutants also escaped into the air through fuel evaporation.

Carbon Monoxide- mentioned before. Interferes with blood's ability to carry oxygen to brain, heart and other tissues. Unborn or newborn children and people with heart disease are in greatest danger from this pollutant, but even healthy people can experience headaches, fatigue, and reduced reflexes due to CO exposure.

Ozone- ground level ozone is the major component of smog. It isn't emitted directly into the air but is produced in atmosphere when gases called hydrocarbons combine with NOx compounds in presence of sunlight.

Sulfur Dioxide- SO2 is emitted when fuel containing sulfur is burned in diesel engines. SO2 exposure

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