The document discusses the major sources and effects of air pollution from vehicle emissions in India. It states that vehicle emissions are one of the primary contributors to air pollution in major cities. The regulated emissions from vehicles include hydrocarbons, nitrogen oxides, carbon monoxide, particulate matter, and soot. When inhaled, these emissions can cause respiratory issues and other health effects. The emissions also contribute to the formation of photochemical smog and acid rain, which negatively impact the environment.