Developmental exposure to the polybrominated diphenyl ether PBDE 209: Neurobehavioural and neuroprotein analysis in adult male and female mice

•Neonatal exposure to PBDE 209 causes behavioural defects in both male and female mice.•Neonatal exposure to PBDE 209 causes increased susceptibility to cholinergic agents.•Neonatal exposure to PBDE 209 causes increased brain levels of tau.

Polybrominated diphenyl ethers (PBDEs), used as flame retardants in polymer products, are reported to cause developmental neurotoxic effects in mammals. The present study have investigated neurotoxic effects arising from neonatal exposure to PBDE 209, including alterations in sex differences, spontaneous behaviour, learning and memory, neuroproteins and altered susceptibility of the cholinergic system in adults.Three-day-old NMRI mice, of both sexes, were exposed to PBDE 209 (2,2′,3,3′,4,4′,5,5′,6,6′-decaBDE at 0, 1.4, 6.0 and 14.0 μmol/kg b.w.). At adult age (2–7 months) a similar developmental neurotoxic effects in both male and female mice were seen, including lack of or reduced habituation to a novel home environment, learning and memory defects, modified response to the cholinergic agent's paraoxon (males) and nicotine (females) indicating increased susceptibility of the cholinergic system. The behavioural defects were dose–response related and persistent. In mice of both sexes and showing behavioural defects, neuroprotein tau was increased.