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Annual Report for Fiscal Year 2015

Annual Report for Fiscal Year 2015


NTP continually accepts and reviews nominations for studies in its research and testing program. The NTP nomination process is open to the public, and nominations can be submitted via the NTP website. Agencies represented on the NTP Executive Committee also identify and forward nominations to NTP. For new studies or research projects of substantial scope and complexity, NTP research concepts or project plans are prepared to facilitate external review as part of a multi-step process with input from NTP participating federal agencies, Board of Scientific Counselors (BSC), and the public.

In July 2014, NTP received a nomination from the Centers for Disease Control and Prevention (CDC)/Agency for Toxic Substances and Disease Registry (ATSDR) to conduct toxicity studies on the predominant chemicals known to be involved in the West Virginia Elk River chemical spill. In response, NTP formulated plans to conduct a number of studies to provide more information about the chemicals and their potential health effects. The NTP Research Project Plan was released and presented to the Board of Scientific Counselors (BSC) in December 2014.

NTP also conducts new studies to extend or explain findings observed in previously conducted studies and address new nominations that are closely aligned with current research efforts. An update on testing nominations was presented to the BSC in December 2014. New studies initiated or approved in FY2015 in response to several recent nominations are provided below.

Questions about the nomination, review, and selection process can be sent to Scott Masten, Ph.D., at masten@niehs.nih.gov.

Research and Testing Projects Initiated in FY 2015
Study Scientist
Nomination Rationale and Project Aims
Due to increased demand and use as an alternative to decabromodiphenyl ether, decabromodiphenylethane is widely detected in indoor and outdoor environments, biota, and consumer products. Subacute and subchronic toxicology studies in rats indicate the liver is a target organ. This compound is included along with other brominated flame retardants as part of a short-term toxicogenomic evaluation.
Firemaster 550 and constituents: 2-Ethylhexyl-2,3,4,5-tetrabromobenzoate
Bis(2-ethylhexyl) tetrabromophthalate
Triphenyl phosphate
Isopropylated phenol phosphate
A widely used flame retardant alternative to polybrominated diphenyl ethers, Firemaster 550 is a mixture of brominated aromatic and aromatic phosphate components and has been widely detected in the environment, biota, and indoor dust. Activity at nuclear hormone receptors has been demonstrated from in vitro studies, yet there is very limited in vivo data for the commercial mixture and some of its components. The two phosphate components (115-86-6 and 68937-41-7) are included in the ongoing aromatic phosphate flame retardant research program. The other two components (183658-27-7 and 26040-51-7) are included along with other brominated flame retardants as part of a short-term toxicogenomic evaluation.
Microcystins are among the most common cyanobacterial toxins that contaminate recreational water and drinking water sources, with documented adverse human health effects and a robust literature on hepatotoxicity and mechanisms of action in animal models. There are no long-term rodent toxicity studies and existing data indicate concern for potential adverse effects during sensitive periods of development. NTP has previously conducted toxicogenomic studies following acute exposure. A new study to provide a comprehensive assessment of developmental, reproductive, and general toxicity following subchronic drinking water exposure is under development.
*CASRN = Chemical Abstracts Service Registry Number