The lame duck Trump administration refused to strengthen limits on smog-causing air pollution. The harms caused by the industrial pollutants — which form ozone when exposed to heat and sunlight — include a range of illnesses and are disproportionately borne by low-income and communities of color. (Washington Post $, E&E $, Wall Street Journal $, The Hill, Roll Call, Politico Pro $, Reuters, E&E $)