Petrol (Lead Content) 60 Mr. Biffen asked the Secretary of State for the Environment what studies and with what organisations, have taken place on the medical aspects of lead in motor gasoline; and what are the latest conclusions on the significance of lead emissions from motor vehicles for community health. Mr. Peter Walker I listed the nine major research studies now being undertaken into lead pollution in my reply of 3rd August to my hon. Friend the hon. Member for Walthamstow, East (Mr. Michael McNair-Wilson), and I am sending my hon. Friend details of those specifically relating to human health. The Government's Chief Medical adviser, supported by a group of medical experts on lead toxicology, advised me last month that he does not find evidence of any general hazard to health from the present levels of lead in the atmosphere, but that it would be advisable to halt or, if possible, reverse the trend in lead emissions. I shall be making a further announcement shortly.