Like it or not, the technological world in which we live is filled with all kinds of poisons. It is a fact of modem industrial life and all too often a cause of death. Almost everywhere we turn we run into large and small factories belching out tons of smoke and debris into the air, adding to the tons continuously pouring out from the exhaust pipes of all our cars and jet aircraft. Add to this aerosol spray fumes and cigarette smoke, and we are talking about more than 150 million tons of air-polluting wastes spewed out each year over the United States and Canada alone.

Air pollution is not our only environmental enemy, however. While most of us have heard about the relationship between long-term sun exposure and the subsequent development of skin cancers and premature skin aging, few are aware that for some individuals the sun's ultraviolet rays can also trigger a wide array of allergic symptoms, either alone or when combined with the ingestion or application of certain substances or medications.

Air Pollution And Allergy Symptoms
Air pollutants are a complex mixture of gases, including ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide, and hydrocarbons. From one place to another the ratio of these compounds can vary significantly, depending on such factors as the kinds and numbers of automobiles in a given location, the number of smokers, the types of nearby factories, and the vagaries of the weather. For example, when warm air masses move over cooler surface air, a condition of stagnant, sometimes life-threatening pollution is created at low altitudes. This situation is particularly dangerous for persons with prior heart or respiratory problems.

Much remains to be learned about the mechanisms by which pollution harms us, but it is believed do so in one or more of several ways. It may be directly toxic to tissues, it may trigger the onset of new allergies, or it may aggravate preexisting ones. Researchers have accumulated convincing evidence that pollution can trigger or aggravate asthma as well as chronic bronchitis. Likewise, the irritating chemicals contained in hair sprays, air fresheners, and cleaning preparations have been found to make the symptoms of preexisting allergic nasal congestion and wheezing flare up in susceptible individuals. An allergic basis has been suggested to explain at least some of the cases of headache, weakness, and nausea that have been associated with the inhalation of gasoline and other hydrocarbon fumes. Since pollutants have been shown to be capable of triggering the release of histamine, the chemical mediator involved in many forms of allergic (as well as nonallergic) inflammatory reactions, some experts have suggested this as a possible explanation for some of these findings.

There is only one way to alleviate the problems related to air pollution: strict enforcement of Environmental Protection Agency (EPA) measures to reduce pollution, and automobile and factory emissions. Allergy-prone individuals and those with other respiratory problems are advised to stay indoors on high-pollution days and to rely on air-conditioning units whenever possible.