EXCLUSIVE

Face masks may raise the risk of stillbirths, testicular dysfunction and cognitive decline in children, 'explosive' new research suggests.

A review of dozens of studies on face coverings suggested they can cause mild carbon dioxide poisoning when worn over long periods.

The German academics who carried out the research believe masks create a pocket of dead space between the mouth and mask, which traps the toxic gas.

They say the build-up of CO2 in pregnant women's bodies could cause complications for the unborn fetus. They point out that CO2 also contributes to oxidative stress, which can affect cognition and cause testicular issues in men.