One of the authors of a groundbreaking report into the link between processed meat and cancer has called for Scotland to mount a public awareness campaign into the health risks.

In an interview, Professor Denis Corpet said the link between nitrite-meat and bowel cancer is “clear” and said parents and consumers need to know what they are eating.

His call came after the Herald on Sunday launched a campaign urging the Scottish Government to ensure that the meat offered in schools and hospitals is free of nitrites. Every opposition party at Holyrood backed the call, meaning that it has majority support in the Scottish Parliament.

READ MORE: Parent groups urge action on process meat in schools

Labour MSP Monica Lennon said: “Professor Corpet is right to demand that more public information is made available in Scotland about the risks posed by nitro-meats. Scottish Labour fully backs a ban on processed meats containing nitrites in our school and hospitals. The Scottish Government can act now to protect and improve the health of the nation, and they should act swiftly.”

In 2015, the cancer wing of the World Health Organisation published a report which placed processed meat, which includes bacon, ham and deli products, in the same carcinogenic category as tobacco and asbestos.

Experts concluded that a daily intake of 50g of processed meat - the equivalent of two rashers of bacon, or one hot dog - increases the risk of colorectal cancer by 18%.

The health risk occurs when processed meat which includes nitrites - a preservative - is heated, producing carcinogenic nitrosamines in the body.

Previous estimates have suggested that 21% of bowel cancers and 3% of all cancers in the UK are caused by eating red or processed meats.

Bowel cancer is the third most common type of the disease in Scotland. Every year around 3,700 people are diagnosed and around 1,600 people die.

Herald on Sunday campaign: time to dump 'nitro' meat from schools and hospitals

However, although the WHO report was published four years ago, scientists and politicians have been frustrated at what they regard as a lack of action from governments across the world.

In February, it was revealed that around three quarters of councils in Scotland are offering nitro-ham to pupils, and nearly twenty local authorities confirmed that they provide other nitrite-meat, including bacon, corned beef and chipolata links.

Nitro-meat is also served in hospitals and, on this basis, we launched a campaign to stop these products from being given to pupils and patients.

Professor Corpet was one of the scientists behind the WHO report and is based at the French National Veterinary School in Toulouse. He said of the research he carried out: “We were able to demonstrate that the rats that were given sausage, or sausage roll, or bacon, are at higher risk for colorectal cancer, than the rats that were given the same meats without nitrites.

“It can be prevented by removing nitrites.”

On governmental inaction since the report’s publication, he said: “The consumption of processed meat is carcinogenic. That was the true statement. It should be enough to act or to change things.”

“They [Governments] did nothing. They were just waiting. I don’t know why. Four years later, nothing was issued, in France, or Europe or in the UK. This was very strange.”

Labour council leader: I want our school meals to be nitrite-free

Professor Corpet said industry mounted a lobbying effort to claim they were not ready to make changes, but he insisted: “The Government should say ‘try to make something which is not carcinogenic’. The Government should say we want safe meat. Some [companies] will just remove nitrites, others will add vitamin e.”

On removing nitrite-meat from Scottish schools, he said it would be hard to implement a ban when parents feed their children ham at home. However, he backed a public health campaign on processed meat and nitrites: “They should be told that they should not normally eat it. As soon as the consumers are aware, they will choose [something healthier].”

He said nitrite-meat could either be phased out over a number of years, or reduced to a level such as once a week: "It is really stupid to have processed meat [presented] as normal meat.”

Professor Corpet also said there is a poverty aspect to the debate: “It is worse for poor people who eat a lot of low price hot dogs, which are full of nitrites while rich people are eating salmon,” he said. “Poor people will move more slowly than rich people.”

However, his main target of criticism is the national food quangos whose job it is to protect the public: “I understand why Governments were not worried, as they have other things to do. But it is the agencies - it is their job.”

The Scottish Government last year launched a consultation on overhauling the food and drink regulations for schools. One of the proposals is for the introduction of a maximum level for red and processed meat.

At First Minister’s Questions on Thursday, Labour MSP Monica Lennon asked Nicola Sturgeon whether she agreed that nitro-meats should no longer be served in Scotland’s schools and hospitals.

The First Minister replied: “There are, of course, international standards, with which we will fully comply. We are absolutely committed to supporting the health and wellbeing of children in schools and have a key role to play in the provision of balanced, nutritious food and drink every day, which our regulations help to ensure.”

Guillaume Coudray: removing nitro-meat from schools and hospitals is "urgent"

A Scottish Government spokesperson said:“Providing healthy meals for children and patients is vitally important. We regularly consider what public health campaigns are necessary and will study with interest the comments from Professor Corpet.

“We expect schools and hospitals to serve healthy and nutritious food. We are currently considering responses to our recent consultation on nutritional school food standards that proposed introducing a maximum level for red and red processed meat, which will help to inform future changes to legislation.”