NTP finds maternal exposure to PBDEs causes liver toxicity in rat pups
Division of the National Toxicology Program (NTP) researchers revealed that exposure to pentabromodiphenyl ethers (PBDEs), which are a mixture of chemicals used as flame retardants, alters the expression profile of liver genes in newborn rat pups. The findings identify early biomarkers of PBDE toxicity that may help predict the risk of toxicity and cancer after long-term exposure.
PBDEs were widely used in household products, including electronic devices, furniture, and textiles, but due to their harmful effects on the thyroid, liver, and developing brain, they were phased out. However, PBDE constituents can still be detected in the environment and in body fluids such as breast milk, which suggests a potential exposure to infants. Because the liver is one of the first organs that respond to toxicants, the authors wanted to determine whether exposure to PBDEs in utero could induce gene expression alterations in the livers of neonatal rat pups.
The scientists treated pregnant rats with either a PBDE mixture called DE-71, or its primary constituent, PBDE-47, which is the most dominant congener detected in human tissues. They found decreased thyroid hormone levels in the pups. Global gene expression alterations involved in detoxification, the antioxidant system, and membrane transport were observed in the pups. These early toxicogenomic indicators may be used to help prioritize chemicals for a more complete toxicity and cancer risk evaluation. (QX)
Citation: Dunnick JK, Shockley KR, Morgan DL, Travlos GS, Gerrish K, Ton TT, Wilson R, Brar SS, Brix AE, Waidyanatha S, Mutlu E, Pandiri AKR. 2019. Hepatic transcriptomic patterns in the neonatal rat after pentabromodiphenyl ether exposure. Toxicol Pathol; doi: 10.1177/0192623319888433 [Online 12 December 2019].