Pierre Souvet, president of ASEF, which represents 2500 doctors, said “hundreds of chemical products are used in the exploration techniques, which are for the most part toxic or even carcinogenic.”

He added that fractured rocks also emit heavy metals or natural radioactive substances that can filter into ground­water supplies.

ASEF’s claims came just weeks before a government conference on France’s energy future takes place on 14-15 September, and weeks after a shale gas lobby group, Amicales des Foreurs (Friends of Drillers), hit out at government inconsistencies in fracking.

Energy