Air pollution is an important pollution problem. Increasing population growth creates more of this pollutant whose major source is burning of fossil fuel, larger number of vehicles and industrial production. As a result, this leads to air pollution. Increasing air pollution of the earth atmosphere would damage to humanбпs health and air quality. Human healths effects include increase the rate of lung disease. For example, Enger and Smith (1994, P333) stated “in Pennsylvania, the city of Donora is located in a valley. In October 1948, the pollutants from a zinc plant and steel mills became trapped in the valley, and dense smog formed. Within five days, seventeen people died and 5910 persons became ill”. Based on the previous example, it clearly shows that air pollution has a negative affect on human health. In addition, air pollution can influence air quality. Normally, atmosphere is composed of seventy nine percent nitrogen, twenty percent oxygen and one percent carbon dioxide. But air pollutant toxic air, it includes sulfur dioxide and oxide of nitrogen. For instant, Tolba (1982, P11) stated, “in1970-1986, global emission rate of oxide of nitrogen increased by almost one-third, while emission of sulfur dioxide increased by approximately eighteen percent.” Therefore, air quality could debase.
Water pollution is also a main pollution issue. Water pollution arises from the rapid growth of population. In order to offer adequate supply to maintain or increase population growth, products from agriculture and industry need water as an input. However, those activities produce wastewater as well, and as a result, wastewater causes water pollution, it includes agriculture water pollution and industrial water pollution. Water pollution has some effects. It would damage the drinking water quality, even if it can influence both plant and animal life, because water pollutant is discharged into river, lake and sea. For example, in China, millions of people live in the drainage basin of Huaihe River, the untreated waste water from paper mills, breweries, chemical plants and tanneries is discharged directly into the Huaihe River. The Henan provincial medical college found that the death rate in the area is 30 percent higher and malignant tumor rate is more than twice as much as the nation average. Furthermore, water pollution especially agricultural water pollution which main component is nitrates, Phosphorus, and pesticides, has a negative affect on human health. Although pesticides are mainly released to kill insect and other pests, it also affects humanбпs body. Tolba (1982, P550) stated, “In 1986, in Sri Lanka as a whole, 66 per cent of deaths by poisoning were due to pesticide poisoning.” So it would affect humanбпs health.
Moreover, global warming is a big concern of the effect of population growth on the environment. More population means more products, in order to offer more products, more agricultural and industrial practices are needed, and meanwhile, more greenhouse gases are released, which causes the greenhouse effect. The main affect of greenhouse effect is it alters climate to be hotter. Hot temperature would damage human health. For example, in July 1995, a heat wave killed more than seven hundred people in the Chicago area alone. In addition, the primary effect of climate change is sea-level rise. This effect is chiefly due to polar ice caps and mountain glaciers to melt rapidly. For example, Sachs (1993, P69) stated “sea-level rise of 0.3 to 0.5 m by 2050 and about 1m by 2100.” In future, people will suffer from flooding when sea level rises.
Higher air temperature also influences ozone density. It leads to ozone depletion. Depletion of ozone would results in more ultraviolet light radiation. Therefore, decrease ozone level at the earth surface would damage to human health, biological life and certain materials such as plastics. Human health effects include increase the rate of skin cancer, especially ozone depletion would lead to increased damage to the eyes, cataracts. According to Tolba (1982, P35) study, “scientists hold that cataracts rise from 0.6percent to 1percent of ozone depletion.”
To sum up, population growth impacts the environment. As the consequence of the increasing of population, nature is polluted. Air pollution, water pollution, greenhouse effect and depletion of ozone alter the environment in a negative way; hence humans become the direct or indirect victims of the effect of pollution. However, it is possible to reduce the effects of population growth on the environment by researching on the protection of natural environment and using the new technologies. Nowadays, humans realize protecting environment is very important. Meanwhile many actions are being taken to try and preserve our environment. The solution may be far a way, but it is coming, as long as there is people in the world that still care.