The reputation of the meat industry will sink to that of big tobacco unless it removes cancer-causing chemicals from processed products such as bacon and ham, a coalition of experts and politicians warn today.

Led by Professor Chris Elliott, the food scientist who ran the UK government’s investigation into the horse-meat scandal, and Dr Aseem Malhotra, a cardiologist, the coalition claims there is a “consensus of scientific opinion” that the nitrites used to cure meats produce carcinogens called nitrosamines when ingested.

It says there is evidence that consumption of processed meats containing these chemicals results in 6,600 bowel cancer cases every year in the UK – four times the fatalities on British roads – and is campaigning for the issue to be taken as seriously as sugar levels in food.

“Government action to remove nitrites from processed meats should not be far away,” Malhotra said. “Nor can a day of reckoning for those who dispute the incontrovertible facts. The meat industry must act fast, act now – or be condemned to a similar reputational blow to that dealt to tobacco.”

Other coalition members include Labour’s deputy leader, Tom Watson; former shadow environment secretaries Mary Creagh and Kerry McCarthy; the Tory chair of parliament’s cross-party group on food and health, David Amess; the Liberal Democrat vice-chair of Westminster’s cross-party children’s group, Joan Walmsley; nutritionist Dr Chris Gill; the Cancer Fund for Children, and John Procter MEP, who sits on the European parliament’s environment, public health and food safety committee.

In a statement issued today, the coalition warns “that not enough is being done to raise awareness of nitrites in our processed meat and their health risks, in stark contrast to warnings regularly issued regarding sugar and fattening foods”.

In 2015 the World Health Organisation published evidence that linked processed meats to 34,000 cases of colorectal cancer worldwide each year – and identified nitrites and nitrosamines as the likely cause.

Data from 262,195 British women suggested reduced consumption of processed meat could lower the risk of breast cancer

Two studies published this year have also raised concerns. Glasgow University researchers collated data from 262,195 British women that suggested reducing processed meat consumption could cut a woman’s risk of developing breast cancer. And a Johns Hopkins University School of Medicine in the US study suggested a direct link between nitrites and the onset of mental health problems. Its 10-year analysis of more than 1,000 people found patients taken to hospital with manic episodes were three times more likely to have recently eaten nitrite-cured meat.

The coalition says the meat industry claims nitrites are essential to combat botulism and infection. But Malhotra said Parma ham producers have not used nitrites for 25 years.

Nitrites give cured products such as bacon and ham their attractive pink colour. Some companies are substituting these with natural alternatives. A year ago, Northern Irish company Finnebrogue launched the “first truly nitrite-free bacon”, with fruit and spice extracts. It is stocked by many major supermarkets. Ocado also sells nitrite-free streaky bacon fromNorthamptonshire-based Houghton Hams and a nitrite-free prosciutto from Unearthed.

• This article was amended on 2 January 2019 to correct the name of Johns Hopkins University.