Plastic may be shrinking penises, says new study

Penises are shrinking, and more boys are being born with genital defects, two Melbourne scientists claim.

They think chemicals in plastics are to blame.

Their controversial stance is based on studies of animals exposed to the chemicals, as well as human data they say shows rates of hypospadia – a penis birth defect causing a range of functionality problems – have doubled in Australia.

However, government regulators say the best-available science shows these chemicals are not having an effect on humans.

In animal studies, exposure when pregnant can have profound effects on an animal's offspring, including infertility, undescended testes and hypospadia.