Second, pollutants are classified into primary (direct emissions) and secondary (atmospheric reactions) categories. Air chemistry is complex; substances such as ammonium nitrate have been ...

There are four main types of industry: primary, secondary ... Buriganga River (Bangladesh), which turns black because of the pollutants. This river used to form part of the end of the Ganges.

Air pollution has become an ever-pressing issue ... of France's Sorbonne Université and colleagues analyzed the ocean's ...