I AGREE with A Kebbell (Letters, April 27) that Jing Wu should be sent back to his own country for running cannabis factories in Southampton.

But I suggest that Mr Kebbell's statement is incorrect with regards to cannabis causing an epidemic of mental health problems.

As a senior mental health practitioner, I believe that it is not cannabis that causes the problem but the additives that cause illness.

In Britain it appears to be accepted that shoe polish, plastics, excrement and other noxious carcinogenic chemicals, can be mixed together and smoked, and called cannabis.

In the majority of cases I think the THC value is negligible, this being the active constituent and mind-altering chemical.

The wards of our mental health units are not full of crazed, psychotic cannabis smokers. Alcohol is more of a problem, and is not addressed because it is legal.

I feel that we should all have the right to grow cannabis for personal use, because it is a natural plant, with many potential benefits. Many millions of people smoke or use it for medical reasons, including depression, and never come into contact with mental health services or the legal system.

The true facts are little known in the mass media. I suggest that Mr Kebbell does a Google search.

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