Trends in Air Pollution Levels (image) Cary Institute of Ecosystem Studies Share Print E-Mail Caption Sulfur and nitrogen pollution reductions have been primarily attributed to emissions controls associated with the Clean Air Act, its amendments, and other rules and legislation. Data reflects trends in air pollution levels from US EPA's National Emissions Inventory. Credit Tony Webster via Flickr Creative Commons Usage Restrictions To promote this press release Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.