Modern society is becoming overwhelmed with great amounts of pollution from cars, factories and an overabundance of garbage. The immense amounts of sulphur dioxide emitted into the air causes high levels of acid in the atmosphere. When this sulphuric acid is absorbed into moisture in the air, poignant rainfalls can be damaging to the external environment. Acid rain is destroying the world's lakes, air and ecosystem. .
Acid rain is killing lakes and decreasing the number of inhabitants in these fresh water bodies. It can cause an ample deduction in the pH levels in the water. At a neutral level the pH in water should be close to seven, yet in these acidic water bodies the pH levels can be as low as four. Each decade the pH levels of lakes around Ontario have become ten times more acidic. The high acid level contained in lakes also causes a decrease in the number of fish inhabiting the water. Acid produces chemical changes in the blood of the fish residing in the water, and their basic body metabolism is altered causing deformities. The fish can suffer from such symptoms as twisted and arched backbones, flattened heads and strangely curved tails. Affected fish are also in danger of becoming sterile, which would put the species at risk of becoming extinct. .
As with sulphur dioxide in rain, mercury is also discharged into the water. There is a direct connection between the mercury rich lakes as there is with those with high acidic levels. This metal becomes concentrated in the blood and tissues of fish causing severe physical abnormalities. .
Acid rain causes air quality to deteriorate. Just as acid rain is damaging to water, it is equally damaging to air quality. Sulphur dioxide diffuses into the air and mixes with moisture causing the pH levels to drop from the normal level. These lowered pH levels form a photochemical smog in the atmosphere. In the air, nitrogen oxides reacts with ozone and some hydrocarbons in the presence of sunlight to form photochemical smog, the kind of yellow-grey haze which appears to be alive and growing in stagnant air masses.