· High levels can change sex of child during pregnancy· Survey of Greenland and east Russia puts ratio at 2:1

Children who eat a diet that has plenty of fruit, vegetables and fish can cut their risk of developing asthma and allergies, according to research that has monitored more than 400 youngsters for the first six years of their lives.

Autism-like behaviour in children is linked to the amount of testosterone they receive whilst in their mother's womb, according to a long-term study of behavioural changes in children.

Scientists in Spain believe they have found the killer parasite that is responsible for wiping out bee colonies from California to Cannes.

British towns and cities are being "ghettoised" by companies that link almost every aspect of our lives to our postcodes, experts have warned