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Annual Report for Fiscal Year 2015

Annual Report for Fiscal Year 2015

RoC Candidate Substances

Candidate Substance
Study Scientist
Primary Uses/Exposures Listing Status and Rationale
A naturally occurring element that is present in different forms, such as a metal and salts. Cobalt metal and cobalt compounds are used in the production of metal alloys for a variety of commercial applications, as a pigment for dying pottery and colored glass, and in green energies. Peer-review meeting July 22, 2015.
Goldenseal root powder
Member of the plant family Ranunculaceae; the root is used as an alternative medicine to treat a variety of ailments.

People are exposed to this botanical by ingesting one of over 150 products, such as dietary supplements and herbal remedies that contain goldenseal root powder.
NTP Board of Scientific Counselors review of draft concept, April 2014.

Planning of cancer hazard evaluation initiated.
Shift work at night, light at night, and circadian disruption
Circadian disruption occurs when endogenous circadian rhythms, daily and predictable variations in biological, physiological, and behavioral processes, are out of phase with the external environment or with each other.

People, by virtue of the nature of their work, lifestyle choices, or residence, are subjected to interruptions in the natural light-dark cycles, leading to the potential for circadian disruption.
NTP Board of Scientific Counselors review of draft concept, June 2013.

Cancer hazard evaluation initiated, and working with Office of Health Assessment and Translation (OHAT) to define the exposures.
Halogenated alkene used primarily for degreasing metals. Peer-review meeting August 12, 2014.

Revised draft monograph posted on RoC website.

5 Selected viruses:

  • Epstein-Barr virus (EBV)
  • Human immunodeficiency virus type 1 (HIV)
  • Human T-cell lymphotrophic virus type 1 (HTLV-1)
  • Kaposi’s sarcoma-associated herpes virus (KSHV)
  • Merkel cell polyoma virus (MCV)


EBV and KSHV: herpes viruses (enveloped; double-stranded DNA genome). Exposure occurs through saliva.

HIV and HTLV-1: retroviruses (enveloped; single-stranded RNA genome). Exposure occurs via breast feeding and perinatal, parenteral, and sexual transmission.

MCV: polyomavirus (nonenveloped, double-stranded DNA genome). It is not known how people are infected with the virus.
Peer-review meeting scheduled for December 17, 2015.
* Chemical Abstracts Service Registry Number
** Currently listed as reasonably anticipated to be a human carcinogen in the RoC.

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