Clean Air Act §115

Clean Air Act §115 allows EPA to regulate any air pollutant on which there have been studies from an  duly constituted international agency; for which US emissions endanger public health or welfare in a foreign country; and where the US has essentially the same right with respect to the prevention or control of air pollution occurring in that country. It has been postulated that this section could serve as a justification for regulating any greenhouse gas recognized under the Paris Climate Accord.