NTP Developmental and Reproductive Toxicity Technical Report on the Prenatal Development Studies of Dimethylaminoethanol Bitartrate (CASRN 5988-51-2) in Sprague Dawley (Hsd:Sprague Dawley® SD®) Rats (Gavage Studies)

Abstract

Dimethylaminoethanol is a close structural analog of choline, an essential nutrient. Dietary supplements containing dimethylaminoethanol bitartrate, a salt of dimethylaminoethanol, are marketed to improve memory and general cognitive function due to the ability of dimethylaminoethanol to increase levels of acetylcholine in the brain. Human exposure to dimethylaminoethanol may also occur through occupational and industrial routes (e.g., spray painting, beverage can lacquering). Dimethylaminoethanol was nominated by the National Institute of Environmental Health Sciences (NIEHS) for toxicological characterization due to concerns for widespread human exposure through its use in industrial and consumer products. Because of the limited literature indicating that dimethylaminoethanol could be a teratogen and reproductive toxicant and because of the possibility for widespread exposure to the salt form of dimethylaminoethanol (dimethylaminoethanol bitartrate) as a dietary supplement in women of childbearing age, the National Toxicology Program (NTP) conducted prenatal developmental toxicology studies in Sprague Dawley (Hsd:Sprague Dawley® SD®) rats. In these studies, time-mated female rats received dimethylaminoethanol bitartrate in sterile water by gavage from implantation on gestation day (GD) 6 to the day before expected parturition (GD 20). To identify dose levels that would appropriately challenge the model system, dimethylaminoethanol bitartrate-related maternal and fetal toxicity were examined in the dose range-finding study followed by the prenatal developmental toxicity study.