In 2024, the greatest concern among adults in the United States was polluted drinking water, which worried 55% of respondents, while 52% of respondents had similar concerns about the pollution of waterways. Meanwhile, 42% of American adults were very worried about both global
warming, or climate change, and air pollution.

Since 1990, the proportion of Americans concerned about air pollution has fallen.

https://www.statista.com/statistics/1361672/biggest-environment-concerns-in-the-united-states/