The dangers of smoking are outlined

Although the numbers of adult smokers in the province have dropped by 1%, the damage caused to the respiratory system by smoking remains a major concern.

Launched by the Health Promotion Agency, the advertisements show that each time cigarette smoke is inhaled, it attacks air sacs in the lungs which can lead to respiratory problems.

Such problems can include the serious lung disease, chronic obstructive pulmonary disease (COPD), which is more common than asthma and includes chronic bronchitis and emphysema.

Dr Brian Gaffney, Chief Executive of the Health Promotion Agency for Northern Ireland, said many people did not discover they had the disease until they had a serious attack of bronchitis.

"Chronic bronchitis and emphysema are long term conditions - both make it hard to breathe, cause shortness of breath, tiredness and coughing," he said.

Those who have quit have greatly improved their chances of avoiding major health problems Dr Brian Gaffney Health Promotion Agency

Globally, 600 million people suffer from COPD and approximately 3m die from the disease each year, he said.

Although it does not go away, it can be treated.

Mr Gaffney added: "The single most important step you can take to make your lungs healthier is to stop smoking.

"It enables the lungs to work better for longer and helps prolong life."

Two additional advertisements will promote the range of nicotine replacement therapies available to help those trying to quit.

According to Dr Gaffney, research has shown that the number of adult smokers in Northern Ireland has dropped by 1%.

He said: "That means there are 12,500 fewer smokers this year. Those who have quit have greatly improved their chances of avoiding major health problems.

"The unlucky ones are the smokers who have died as a result of their habit."

The campaign runs until the end of the month.

A helpline has been set up to support those who want to give up and to encourage ex-smokers. The number is 0800 858585.

Meanwhile, smokers in Dublin are being targeted in a new initiative with 20,000 portable ashtrays being given out by the city council in the next two weeks.

Cigarette butts make up almost a third of all litter in Dublin and on-the-spot fines of more than 100 euro are already in place.