Subacute oral exposure to benzo[α]pyrene (B[α]P) increases aggressiveness and affects consummatory aspects of sexual behaviour in male mice

Benzo[α]pyrene (B[α]P) is a neurotoxic pollutant which is also able to affect some behaviour and cognitive function. Here we report that a subacute oral exposure to B[α]P increases aggressiveness and affects copulatory behaviour in male mice. Indeed, after 3 weeks of exposure to B[α]P at 0.02 and 0.2 mg/kg, we have observed that B[α]P 0.02 mg/kg-treated male mice are more aggressive than control mice in resident-intruder test because a significant decrease in the latency time of the first attack and a significant increase in the number of attacks in B[α]P 0.02 mg/kg-treated mice were found. On the other hand, we have found that subacute exposure (4 weeks) to B[α]P, does not affect the appetitive aspects and sexual motivation in copulatory behaviour because the latency to the first mount between control and B[α]P-treated male mice was not significantly different. We have nevertheless, surprisingly found that B[α]P (0.02-0.2) mg/kg-treated mice have performed significantly more sexual behavioural acts including mounting, intromission latency and intromission frequency than control mice. Although these last results suggest that B[α]P improves the consummatory aspects of sexual behaviour, we cannot conclude that this neurotoxic pollutant has advantage of sexual function because B[α]P has been shown to alter the monoaminergic neurotransmitter system and causes endocrine dysregulation via toxic effect.