Yes, it is! They will cause the acid rain.
Its reactions in the air are responsible for acid rain and photochemical smog
Volcanoes often emit a harmful gas called sulfur dioxide. Sulfur dioxide is an air pollutant. It causes acid rain.
Both the classic London smog (sulfur dioxide, fog and particulates) and the present photochemical smog (ozone, PAHs, hydrocarbon and nitrogen oxides oxides) are air pollution resulting from primary air emissions like hydrocarbons, sulfur dioxide, nitrogen oxides.
This is the sulfuric acid - H2SO4.
lead
sulfur trioxide
yes it is as it is produced by industries and mixes with water droplets and causes acid rain to fall
sulfur dioxide and sulfuric acid
classical or chemical smog
Air can be divided into compounds and elements. The major components of air are the elements nitrogen and oxygen, but most air also contains carbon dioxide and, at least in industrialized area, also oxides of nitrogen and sulfur that are compounds.
Sulfur dioxide
A lot of substances are not air pollutant. You must specify which kind of substance do you refer as a probable air pollutant.