CHEMICAL safety checks need to be tightened up around the world to protect children from a "silent epidemic" of brain disorders, according to experts.

In the past seven years, the number of recognised chemical causes of brain development conditions has doubled from six to 12, two leading scientists in the US, who conducted a review of study evidence, found.

The list of chemicals known to damage the human brain but not regulated to safeguard children had also risen from 202 to 214. These hazardous substances were found in everyday items including clothing, furniture and toys, experts said.

They have called for universal legal requirements forcing manufacturers to prove that all existing and new industrial chemicals are non-toxic before they reach the market place.