CANNABIS SMOKE 'WORSE' THAN TOBACCO

Smoking pure cannabis is more harmful to lungs than tobacco, a health
charity is warning.

A study by the British Lung Foundation found that just three cannabis
joints a day cause the same damage as 20 cigarettes.

And when cannabis and tobacco are smoked together, the effects are
dramatically worse.

Evidence shows that tar from cannabis cigarettes contains 50% more cancer
causing carcinogens than tobacco.

Dr Mark Britton, chairman of the British Lung Foundation, said: "These
statistics will come as a surprise to many people, especially those who
choose to smoke cannabis rather than tobacco in the belief it is safer for
them.

"It is vital that people are fully aware of the dangers so they can make an
educated decision and know the damage they may be causing."

Dr Britton emphasised that the British Lung Foundation report - called A
Smoking Gun? - was "not about the moral rights and wrongs of cannabis".

But, he said, they simply wanted to make sure people were completely clear
about the respiratory health risks involved.

Misconception

Surveys carried out earlier this year showed that 79% of children believed
that cannabis was 'safe'.

Only 2% understood correctly that there are health risks associated with
smoking the drug.

The British Lung Foundation report also shows that the health dangers of
cannabis have substantially increased since the 1960s.

That means that clinical studies carried out in the sixties and seventies
may well underestimate the ill effects of smoking the drug.

This is due to increased amounts of THC - or delta-9 tetrahydrocannabinol,
the major active chemical compound - in the cannabis consumed today.

Pleasure Receptors

In the brain, THC connects to specific sites called cannabinoid receptors
on nerve cells and thereby influences the activity of those cells.

Many cannabinoid receptors are found in the parts of the brain that
influence pleasure, memory, thought, concentration, sensory and time
perception, and coordinated movement.

Dame Helena Shovelton, chief executive of the British Lung Foundation,
said: "Puff and inhalation volume with cannabis is up to four times higher
than with tobacco - in other words you inhale deeper and hold your breath
with the smoke for longer before exhaling.

"This result in more poisonous carbon monoxide and tar entering into the
lungs."

The British Lung Foundation is calling for the government to implement a
public health education on the health risks of cannabis.

The charity will also be pushing for further research into cannabis and the
lungs and its potential link with the development of chronic obstructive
pulmonary disease.