A Californian ballot measure dating from 1986 requires producers and distributors of carcinogens to be upfront about them. One result is a message on every petrol pump in the state warning motorists the fuel they’re buying “contains substances known to the state of California to cause cancer”. The UK has no equivalent. If it did there might be no grounds for more than 100 former and serving military personnel in the UK to be suing the ministry of defence because of cancers attributed to years of inhaling jet fuel fumes while working on and flying helicopters for the forces. Richard Sutton, fighting for his life after years of cancer treatment and multiple operations, is one of five already to have received a payout. Question for the next government: if tobacco has to be honest about its threats to health, why not oil?