Contoh Report Text 5: AIR POLLUTIONEvery day both industrial and domestic chimneys emit vast amounts of dirt and harmful gases. The exhaust fumes from thousands of car engines add to this huge volume of filth, Sulphur dioxide, produced mainly by the burning of coal and oil, combines with the moisture of the air to form sulphuric acid. This eats away stone, brick and even metal. Doctors reason that if it can do this, it must damage the lungs of people who breathe it, especially over a period of many years.
Usually the effects of air pollution are not instantly noticeable. Occasionally, though,, there have been catastrophic “smogs”. (The word smog is a combination of smoke and fog). One of these occurred in the town of Donora, Pennsylvania, in the U.S.A. The valley in which the town lies traps the smoke and fumes from the steelworks and chemical plants that fill it.
One day, in October 1948, unusual weather conditions prevented the smog from lifting by the afternoon, as it normally did. Instead, it hung over the town for three days. By the end of the third day, nearly 6000 people were ill. More than 60 percent of those aged 65 and over were seriously ill. 20 people died. At last a heavy rain shower cleared the smog.
One of the chief causes of air pollution in many cities is the internal combustion engine. Cars, lorries, and buses give out the gas called carbon monoxide, which in high concentrations can kill a person in a confined space. Cars also throw into the air fine particles of rubber and asphalt from their tires and the road, and particles of asbestos from their brake-linings. These can cause damage to the lungs when breathed in.
Another source of pollution is nuclear power station which produce a great amount of poisonous radio-active waste. This waste must be sealed up and buried beneath the ground or seabed so carefully that there is no danger of leakage. Some scientists are very worried that we are not being careful enough with nuclear waste. It may not all be buried safely. Also, they fear there may be a serious accident at a nuclear power station, releasing deadly radiation into the air.