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What is acid rain? Acid rain is caused by emissions of sulphur dioxide and nitrogen oxides. Although natural sources of sulphur oxides and nitrogen oxides do exist, more than 90% of the sulphur and 95% of the nitrogen emissions occurring in eastern North America ....

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.... and throat irritations. An indirect effect of acid rain on humans is that the toxic metals dissolved in the water are absorbed in fruits, vegetables and in the tissues of animals. Even though these toxic metals do not directly affect the animals, they have serious effects on humans when they are being eaten. How did it happen? One of the main causes of acid rain is sulphur dioxide. Natural sources that let out this gas are volcanoes, sea spray , rotting vegetation and plankton. However, the burning of fossil fuels, such as coal and oil, are largely to be blamed for about half of the emissions of this gas in the world. When sulphur dioxide gets in ....