Is carbon dioxide a pollutant?
Increased atmospheric CO2 from human activities is warming the planet. This poses many threats, including more extreme and destructive weather events, expanded disease vectors, biodiversity loss, and sea-level rise, which could displace billions of coastal dwellers.
The Clean Air Act mandates that the U.S. Environmental Protection Agency keep a list of pollutants that “may reasonably be anticipated to endanger public health or welfare.” In 2007, the Supreme Court ruled that CO2 and other greenhouse gases are pollutants that may be regulated by the EPA.
The misconception that CO2 cannot be a pollutant because it helps plants grow oversimplifies its impact on the climate, which includes the aforementioned threats. Additionally, while more CO2 spurs photosynthesis and reduces water loss in crops, it also exacerbates drought and desertification, making its long-term impact on agriculture unclear.