A HEALTH boss today urged the Government to put the same effort into advertising the dangers of cannabis as it does with cigarettes.

And health and drugs professionals in East Lancashire welcomed the downgrading of cannabis -- but said more research and publication of health risks are needed.

Although the drug will remain illegal, the only time, after Thursday, that arrests will be made for cannabis in Lancashire is if the person is under 18, possessing it near schools, youth clubs and play areas or smoking it in public.

Steve Morton, director of public health for Hyndburn and Ribble Valley Primary Care Trust, said: "Reclassing cannabis is probably the right thing to do but they need to now put the same effort into publicising the health risks as they do with smoking tobacco."

Each year the Government gives the British Heart Foundation £7.5m to run an anti-smoking advertising campaign.

Dr Morton added: "We now know more about cannabis than we have before and it is probably more harmful than we used to think, but it has been recognised that cannabis is perhaps the most widely used drug and we need to alert members of the public to the dangers."

Conrad Eydmann, development manager of Lancashire Drugs Action, said: "I am happy it remains illegal as at the end of the day it's a drug that can cause problems. Whether the evidence is robust or not you cannot afford to decriminalise something that could be harmful."

Health problems relating to cannabis, Mr Eydmann said, included those generally linked to tobacco smokers, because the majority of cannabis use was coupled with tobacco.

These include chest and lung problems including the risk of lung cancer.

The use, he said, with tobacco, could also lead to an enhanced feeling of dependency on cannabis, although the addiction was actually to the nicotine.

He said: "You cannot become physically dependent on cannabis but you do see those who develop a psychological dependence in the same way as with cocaine. What you see is individuals who feel they cannot cope with getting through the day without it, and it becomes a crutch.

"Another side effect from using cannabis relates to slowed reaction times and the ability to concentrate, which could lead to disastrous consequences if the user was to drive or use dangerous machinery."

Mental health issues are another concern.

Mr Eydmann said: "Although there is no completely robust evidence there is an increasing link with use of cannabis and the activation of underlying mental health problems such as paranoia or schizophrenia."

Max Marshall, Medical Director for Lancashire Care NHS Trust, said: "There is strong evidence from scientific studies that cannabis use substantially increases the risk of developing schizophrenia."