Data extracted from the original ToxCast hit-call matrix showing: 1) the number of chemicals that were active (numbers within parentheses give the number of chemicals with associated SMILES strings), 2) the number of those chemicals that contain any of the structural alerts developed by Mellor et al. (2016b), and 3) the number of chemicals that contain at least one structural alert for the specific nuclear receptor (numbers within parentheses are the percentage of chemicals with SMILES strings that contain a nuclear receptor specific structural alert).