The ContaminantDB is a unique bioinformatics resource that combines detailed contaminant data from different online references and databases on contaminants. The database currently houses 54,249 compounds. It is both modelled after and closely linked to the Human Metabolome Database (HMDB) and DrugBank. The databases and sources used to gather contaminant data includes IARC Carcinogens Group 1, 2A, 2B, 3 and 4, Drugbank drugs and metabolites, Disinfection ByProducts, My Exposome Chemicals, ToxCast and Tox21 Chemicals, EPA High Production Volume Chemicals, OSHA Hazardous Chemicals, Clean Air Act Chemicals, T3DB Toxins, ECHA Substances of High Concern, DEA Chemicals, EPA Endocrine Screening Chemicals, EAFUS Chemicals, and OECD High Production Volume Chemicals.