Each line of the following passage has one mistake related to either grammar or vocabulary usage. Find and correct them.

Air pollution is a cause for ill – health in human beings. It a lot of countries, there are laws limited the amount of smoke which factories can produce. Because there isn't enough information on the amount of smoke in the atmosphere, doctors have proved that air pollution makes lung cancer. The gases from the exhausts of cars have also risen air pollution in most cities. The lead in petrol produces a poisoned gas which often collects in busy streets surrounding by high buildings. Children who live in areas where there is a lot of lead in the atmosphere cannot think as quick as other children and they are clumsy where they use their hands. There are long-term effects of pollution. If the gases in the atmosphere continues to increase, the earth's climate will become warmer. A lot of ice near the Poles may water and may cause serious floods.