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. Acid rain causes 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. These pH levels of four contain more than ten percent acids than that of normal rain and one thousand times more acid than neutral water. Each decade the pH levels of lakes around Ontario have become ten times more acidic. The high acid levels contained in lakes also causes a decrease in the number of fish dwelling in these lakes. Also Aacid produces chemical changes in the blood of the fish, and their basic body metabolism is altered@ (Howard & Perley, 1980, p. 24), and can cause deformities in these inhabitants. They have twisted and arched backbones, flattened heads and strangely curved tails. In pH levels of four there is little left in the lakes besides rock bass, pumpkinseed and lake herring. 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. Acid rain causes traumatic effects in natural lakes and rivers. Acid rain causes air quality to deteriorate. As in water, acid rain causes the pH levels in the air to decrease.