CYP1A1 and Disorder of energy metabolism: What’s more, we investigated two possible toxicological mechanisms for the first time including 1) PM2.5 exposure might induce energy metabolism disorder by inhibiting mitochondrial respiratory, and thus result in the deficiencies of amino acids and nucleotides; 2) the AhR-CYP1A1 pathway was activated and might cause ROS generation after exposure to PM2.5.