求一篇关于污染物的英语墙报

这一片应该不会很难把，不懂的字眼 用Gooogle translator 查吧

Pollutants & Emission Sources

A number of air pollutants can cause damage to health. Six major air pollutants (Carbon Monoxide, Lead, Nitrogen Dioxide, Ozone, Particulate Matter, and Sulfur Dioxide) have been identified as causing health effects at concentrations in the ambient air (the outside air we breathe) above thresholds established at levels known to be safe. These pollutants are referred to as "criteria pollutants" and a National Ambient Air Quality Standard (NAAQS) has been established for each based on health related criteria and data.

The following pages have information on the criteria pollutants, other air pollutants and emission sources:

Acid Rain Acid rain, which may damage lakes and streams, occurs when emissions of certain air pollutants react in the atmosphere to form acidic compounds that are then deposited on the earth’s surface. The Clean Air Act limits the emissions of