Question

Why has pollution become a global concern?

Answer 1

Pollution is an international issue because contaminated media (air and water) are shared by countries.

Explanation:

Transboundary pollution issues are atmospheric pollution, global climate change due to increasing carbondioxide in our atmosphere, river and lake pollution (because some rivers and lakes are shared by different countries).

Polluter is responsible for pollution but some other nations (such as downstream countries if it is a river pollution) suffer from pollution. Nobody can keep pollution to stay in close vicinity of the source. For this reason, pollution is an international and transboundary issue. For this reason, a global concern is a reality about any type of pollution.