What are four major types of pollution?

Question

that are a threat worldwide

Answer 1

Air, water, soil, noise, etc.

I don't know how much of a "threat" noise pollution is. But it has some negative attributes.

Answer 2

Air Pollution

Water Pollution

I cant think of the others

Answer 3

Vehical Exhaust

Buring Fossil Fuels

Dust

Sea Salt

Volcanic Gases and Ash

Smoke from Forest Fires

Smog