TONY Blair should think about his own constituents when it comes to banning smoking in the workplace, according to one of the UK's largest unions.

Sedgefield, the PM's own seat, tops the North-East league for deaths per year directly linked to lung cancer, according to official figures released by the GMB union.

For every 100,000 people who live in Sedgefield 50 die every year of lung cancer, a death rate which is a staggering 80 per cent above the national average.

The figures were released by GMB as part of a campaign to persuade the Government to commit to a total working ban in all workplaces.

Currently the Government intends to exclude private clubs, non-food pubs and a number of other workplaces from their proposed smoking ban legislation.

GMB are concerned about the health of members working in smoky atmospheres, including workers in the expanding casino sector.

The union argues that a total workplace smoking ban is the only way to protect people from the dangers of inhaling smoke.

Smoking is known to be the main cause of lung cancer, an aggressive form of cancer which is difficult to treat and has a poor survival rate. Overall the North-East and Yorkshire have a death rate from lung cancer above the national average.

Second out of 23 areas in the North-East, with 47 deaths per 100,000, is Newcastle. The third worst area is Gateshead with 46 people per year.

Within Yorkshire and Humberside, the area with the highest lung cancer death rate is Richmondshire (29.37 per 100,000) then Scarborough (26.92 per 100,000).

Apart from campaigning for a total workplace smoking ban, GMB is also threatening to take legal action over smoking related illness from passive smoking.

GMB has joined forces with the Roy Castle Lung Cancer Foundation to press for a compete workplace ban.

Mike Unger, chief executive of the Roy Castle charity said: "Fifteen per cent of patients with this devastating disease have never smoked.

Many of these will be people who come into contact with second-hand smoke at their workplace. The Government has a duty to protect everyone. I urge the Government to be brave on this issue and make a total ban law."

Health Secretary Patricia Hewitt insists that the proposals were still a big step forward because the "vast majority" of the North-East's workplaces would be smoke-free.