On October 2, 2014, HHS released the 13th RoC. This cumulative report contains 243 listings, of which four were newly reviewed. The newly reviewed listings, include ortho-toluidine, listed as known to be a human carcinogen, and three substances: 1-bromopropane, cumene, and pentachlorophenol and byproducts of its synthesis (hereinafter referred to as pentachlorophenol), all listed as reasonably anticipated to be human carcinogens.
Other RoC activities in FY2015 were related to conducting the cancer hazard evaluations of several candidate substances. The cancer hazard evaluation of trichloroethylene was completed, including preparation of the revised draft monograph and response to the peer-review report, and the NTP Board of Scientific Counselors was updated on the peer-review meeting in December 2014. The final monograph was published on the NTP website in January 2015. In July 2015, NTP convened a panel of experts to peer review the draft RoC monograph on cobalt and certain cobalt compounds. The monograph is being revised based on the peer-review comments. The Office of the Report on Carcinogens has also worked on the preparation of a series on monographs for five viruses. The peer-review meeting is scheduled for December 17, 2015. Cancer hazard evaluations are ongoing for two other candidate substances: (1) goldenseal and (2) shift work at night, light at night, and circadian disruption.
The Handbook for Preparing Report on Carcinogens Monographs was published in July 2015. It lays out the methods for conducting the cancer hazard evaluation, from the planning and problem formulation stage to reaching a preliminary listing recommendation. The handbook is a living document and incorporates principles of systematic review. Key elements related to increasing the transparency of RoC reviews include methods to evaluate risk of bias and sensitivity of cancer studies in humans and experimental animals, and guidelines for synthesizing evidence across the studies to reach preliminary level of evidence conclusions.