In October 2014, the U.S. Department of Health and Human Services (HHS) Secretary Sylvia M. Burwell released the 13th Report on Carcinogens. The Report on Carcinogens is a congressionally mandated report prepared by NTP for the HHS secretary. The report identifies agents, substances, mixtures, and exposures in two categories: known to be a human carcinogen and reasonably anticipated to be a human carcinogen.
The 13th report includes 243 listings. Ortho-toluidine, used to make rubber chemicals, pesticides, and dyes, was reevaluated and is now listed as a known human carcinogen. Three substances were added as reasonably anticipated to be human carcinogens. They include 1-bromopropane, used as a cleaning solvent and spray adhesive; cumene, used to make phenol and acetone and found in fuel products and tobacco smoke; and the wood preservative mixture pentachlorophenol and by-products of its synthesis.