Effects on other living organisms may be far more important than the actual risk to man. Certain organisms, in particular phytoplankton, zooplankton, and the larval stages of fish, are very sensitive to small increases of ultraviolet exposure. This decrease in the food chain and in the oxygen output from the ocean's plants will have serious and dramatic repercussions on all human life.
Addressing the Problem
A research model indicates that the global ozone will be 6 percent lower in the year 2030 than it was in 1970. (14) This will increase the incidence of nonmelanomatous skin cancer by 12-36 percent and melanoma mortality by 9-18 percent. An assessment by the U.S. National Aeronautics and Space Agency indicates that ozone depletion is occurring globally and is progressing faster than previously realized. What we need to do is minimize the use of chlorofluorocarbons. CFCs are in aerosols, foam blowers for items such as hamburger cartons and drinking cups, refrigerants and cooling systems, and solvents for computer circuits. In most instances, nonchlorinated substitutes are available or can be developed. Some countries are recommending a 20 percent reduction of CFCs; the United States is recommending a 50 percent reduction. However, some CFCs remain in the air for over a century. Halones, used in fire extinguishers throughout the world, are synergistic with CFCs. Once these chemicals are stopped from being used and once the ozone depletion has been resolved, it will be many decades before any useful improvement is seen.
If pentane is used instead of chlorofluorocarbons as the blowing agent to produce foam products, ozone is produced both in the stratosphere and at the ground level. Now let's assume that pentane is used to produce a polystyrene drinking cup. Which do you think costs more to your pocketbook and the environment, a paper cup or a polystyrene cup? No, the paper cup costs more by far. A paper cup costs more to make from the standpoint of raw materials (wood, bark, petroleum fractions), finished weight, wholesale price, utilities needed to produce it (steam, power, cooling water), waste products produced, and air emissions (chlorine, chlorine dioxide, reduced sulfides, particulates). (15) The polystyrene cup is easier to recycle and ultimately to dispose. Here again we have the proper technology, we simply need to do something about it.
We can all do something about this major problem. We can write to our senators and congressmen to encourage them to completely ban all chemical compounds that will further deplete the ozone layer. Again, the solution to this problem is totally within our control.
Ozone pollution at ground level is different from the naturally occurring protective ozone layer in the upper atmosphere that shields the Earth from harmful ultraviolet rays. Ozone at ground level is the most widespread air pollutant in any industrialized country and is formed when car exhaust and other emissions from industries react with sunlight.
In a study involving children in a summer camp, researchers found that there was enough ozone pollution in the air at ground level to cause significant impairment of lung function in about 70 percent of the campers. The effects of this ozone pollution at ground level persisted for about eighteen hours after exposure, and the suspicion is that even small changes in the lungs' capacity may lead to cell damage and ultimately to chronic respiratory illness.
Ozone pollution is a health hazard, particularly for those with respiratory illnesses and those who exercise out-of-doors. Ozone at ground level has been linked to cancer, lung disease, heart disease, and many other chronic illnesses. In healthy people, ozone impairs the ability of the lungs to absorb oxygen. Repeated exposure to ozone leads to early stages of lung damage similar to that seen from smoking. Respiratory infections are quite common in people who breathe more ozone at ground level than others. People who are asthmatic do much worse when the ozone level is high. Cardiac patients do worse because the amount of oxygen in the air is reduced. The incidence of mortality also is increased in older people who have respiratory illnesses in areas with high levels of sulfur oxides in the air.
Most cities exceed the federal ozone standard. Los Angeles has the most and other cities that have a large amount of ozone smog include New York, Philadelphia, Trenton, Baltimore, Hartford, Chicago, and Houston. Some national parks like Acadia, Shenandoah, and Sequoia National Parks have higher ozone levels than some cities because of their proximity to the major cities with smog and/or the air currents around them.
Ozone forms when certain compounds react with sunlight. These compounds include nitrogen oxides and volatile organic compounds. Nitrogen oxides are derived from motor vehicles as well as industrial plants. Volatile organic compounds come from things like backyard barbecues and dry cleaners.
Smog is derived predominantly from ozone as well as from volatile organic compounds, carbon monoxides, nitrogen oxides, sulfur oxides, and other particulates. These compounds are derived from bakeries during the fermentation process; dry cleaning chemicals; paints; wood-burning stoves and starter fluid used to ignite charcoal; and industries and motor vehicles using fossil fuels. However, ground level ozone is clearly the most widespread air pollution problem we know today.
The Environmental Protection Agency did a study involving nonsmoking men in a room where ozone was close to the federal maximum. After five hours of walking and then bicycling, 80 percent of these men began to cough and feel chest pains. In a study of men who exercised for only two hours while breathing ozone that was below the federal maximum but still above the ambient air in very rural settings, 80 percent experienced serious symptoms of the lower airways. The airways were inflamed, and biochemical changes occurred with a subsequent impaired immune response at the local sites of the lung.
Ground level ozone can be controlled. We must insist again that the fuels burned are better and cleaner so that less volatile organic compounds, nitrogen oxides, and other ozone-producing compounds are emitted. And although the 1990 Clean Air Act is thought to be the most expensive environmental legislation ever passed in terms of attaining the new standards, enforcement of these standards must also be rigorous.
There are two major forms of ultraviolet light emitted from the sun, ultraviolet-A (UVA) and ultraviolet B (UVB). The UVB is the more harmful of the two and has wavelengths between 290 and 320 nanometers, wherea j UVA has wavelengths between 320 and 400 nanometers, which is where the visible light spectrum begins.
The current package labeling on a sunscreen product states its ability to protect against UVB, the form responsible for causing sunburn and skin cancers. UVA can also cause skin cancer but, in addition, causes skin damage and premature aging of the skin. New labeling regulations by the FDA will reflect the UVA protection as well. You need to have protection from both forms of ultraviolet light.
What type of sunglasses should you use to protect your eyes from the harmful ultraviolet rays of the sun? People frequently ask does the cost of the sunglasses reflect the protection they afford? Thirty different makes and prices of sunglasses were tested for ultraviolet transmission. Each of the sunglasses completely filtered all UVB radiation, hence no danger to the eye would be anticipated if sunglasses were worn. With respect to transmission of UVA to the eye, the results varied greatly but had no relation to price. (16) Hence, when you see a person with a pair of sunglasses costing $200, you can laugh quietly knowing that your $2 sunglasses give you just as much protection.
Indoor air pollution has become a major problem as well, causing both specific illnesses and the minor complaints that now constitute the "sick building syndrome."(17) Indoor accumulation of radon, passive smoking pollutants, combustion pollutants from stoves, chemi-cal emission from plastics, and insulation materials are just a sample of the indoor pollutants that are hazardous.
When radon is present in the soil below buildings, or in surface water or construction materials, particularly granite, the indoor radon concentration will exceed the acceptable standard as set by the Environmental Protection Agency at 4 psi/liter (psi are pica Curies). (18) Some homeowners have spent $1,000 to $2,000 to comply with this standard. In 1988, however, Congress passed the Indoor Radon Abatement Act, which forces the EPA to set the standard of indoor radon equal to that of outdoor radon. The average cost to homeowners to comply, with the newer standard could be close to $10,000.
Radon has now been implicated in up to 20,000 deaths from lung cancer in the United States. (l9) A person living in a house with an indoor radon level of 4 psi/liter has the same risk of developing lung cancer as a person who smokes half a pack of cigarettes per day. ° The risk of lung cancer is increased more if people smoke cigarettes and are exposed to radon, as in the case of coal miners. (21)
Freestanding stoves without chimneys increase the indoor air concentration of nitric oxide, benzo(a)pyrene, and sometimes even sulfur dioxide. These pollutants increase respiratory disease. Kerosene stoves also produce many pollutants, several of which are carcinogenic. Heat exchangers, cooling towers, and leaky shower heads provide favorable culture media for many microorganisms. These bacteria and other organisms disperse in droplets and remain airborne by mechanical or thermal air movements. Legionella (Legionnaires' disease) and many other organisms have been detected airborne in closed indoor situations.
Passive smoking is a serious problem in indoor air pollution. Passive smoking is responsible for doubling the lung cancer rate in persons exposed to it as compared to those not exposed to passive smoking. (22) In past years it has been up to the individual to avoid such passive smoking, but things have changed. A nonsmoking Swedish office worker was awarded damages for a lung cancer he developed from breathing other people's tobacco smoke in the office. Now in the United States there are many laws to protect the passive smoker in certain public areas and on domestic airline flights. Hopefully more and more such laws will protect us in all public areas.
Other indoor pollutants come from materials that are used in the construction of modern buildings, such as formaldehyde, isocyanates, solvents, and volatile synthetic organic compounds. These are used in the manufacture of insulin, decoration, and equipment. We know that formaldehyde is associated with human cancer.
To protect ourselves against indoor pollutants, we simply need to have adequate ventilation. Studies have been done and show that one or more air changes per hour should be provided and that the carbon dioxide concentration should not exceed 0.5 percent. As we move toward a service-oriented society in America, with more people working in offices, this problem is everyone's concern. However, it can soon be eliminated if we work to modify the environment.
Water Treatment and Pollution
In 1960 W.C. Hueper warned that the drinking water in the United States was contaminated with natural and manmade pollutants and that some of these were potentially carcinogenic. (23) In addition, other reports in the past ten years have shown that there are carcinogens in the drinking water and that in some areas, contaminated water has been associated with an increased cancer risk and other medical problems.
There are several groups of drinking water contaminants that may be carcinogenic. Synthetic organic chemicals comprise the first group, whose carcinogenic potential is of greatest concern. The United States Environmental Protection Agency has found over 700 organic chemicals in our drinking water, (24) and that number probably represents a small fraction of the actual number that exists. Forty of these are carcinogens, and three (benzene, chloromethyl~l ether, and vinyl chloride) are associated with cancers in man. (25) Drinking polluted water is said by the EPA to be one of the top four health hazards to Americans, but enforcement of existing laws has been poor at best, and enforcement of additional laws and standards will be difficult. The standard set by the EPA allows municipalities to average their water toxicities over a year. For example, much more chlorine is added to water during summer months to hold down microorganisms. In some cities the tap water level of chlorine carcinogens exceeds the standard by 20 percent during these months. The same spike of toxicity holds true for nitrates and pesticides, both used seasonally for lawn beautification and farming.