Alex Markham: There is no right to smoke at expense of other people's health

For the ban: Chief Executive of Cancer Research UK

We have known since the 1950s that smoking causes lung cancer. We have also known since the early Eighties that exposure to other people's smoke increases your risk of lung cancer by about a quarter and heart disease by the same degree. Thousands of people are exposed to its 4,000 poisons - which include arsenic, benzene and formaldehyde - at work.

Today, MPs will vote on this legislation. Some are still wavering. I do not doubt that those opposed suggest that ventilation systems are the answer. But no system on the market can remove the invisible and lethal gases that smoke contains. And, staff at pubs and members' clubs deserve a safe working environment.

The idea that smoke is less dangerous in certain environments is illogical and dangerous: second-hand smoke kills an estimated 600 workers a year in the UK. We can no longer regard a smoky atmosphere as an inevitable in venues when it results in death and disease. As the Joint Commons and Lords Committee on Human Rights recently reported, any exemptions would be a breach of human rights.

I ask MPs to seize this opportunity to enact the most important piece of public health legislation that I am likely to see in my lifetime. Ireland has adopted the measure wholeheartedly since it was introduced in 2004 (with almost all venues compliant after one year, and many smokers having used it as an opportunity to quit); Scotland will enact similar legislation on 26 March, and Wales and Northern Ireland will also do so.

The only question remaining is, if this measure is recognised as critical for protecting Scottish, Irish and Welsh workers, why do English workers not merit similar protection? Smokers do have the right to smoke. But not at the expense of other people's health.