The biggest argument against protecting the freedom of the press in the UK can be summed up in two words: “Daily Mail”. Now, it must be said from the start that the Daily Mail is capable of fair and objective reporting regarding many things even including cannabis. Indeed there have been a number of instances over the years where the paper has run objective and factual reports about various aspect of the subject, but these are greatly overshadowed by the paper’s apparent desire to pursue an agenda of deliberate misinformation designed to paint cannabis  as a dangerous and destructive drug that must remain criminalised.

This was illustrated with an amazing report this week – amazing even by the standards of the Daily Mail – which claimed to be a news report and yet was so far from being factually correct as to be truly jaw dropping. The story in question was published on 26th October, headlined “Just ONE cannabis joint ‘can bring on schizophrenia’ as well as damaging memory” – (read it here). The report concerned a study by Matt Jones and others at Bristol University entitled “Dysfunctional Prefrontal Cortical Network Activity and Interactions following Cannabinoid Receptor Activation” and can be seen in full here on the CLEAR website.

Now, the first thing to notice is the phrase

‘can bring on schizophrenia’

is in quote marks, this means it is a reported comment from someone.  Strangely this quote is not attributed to anyone in the study, indeed it is not, in fact, a quote from anyone.

Beneath the headline were two bullet points:

  • Strongest evidence yet, claim scientists
  • Rats used in experiments
So the thrust of the story is quite clear; according to the Daily Mail scientists have found the strongest evidence to date that cannabis “brings on” schizophrenia and what’s more, this time the scientists are actually saying so with some degree of certainty. The warnings about the mental health risks of cannabis would seem to be true. The story goes on to state
Smoking just one cannabis joint can bring on symptoms of schizophrenia, a study has found.
So according to the Daily Mail not only is this new and very strong evidence that cannabis has a causal role in the creation of mental illness, but also that it’s something that can happen after just one joint. Then we are told:
Researchers at the University of Bristol have, for the first time, looked in detail at the changes in the brains of cannabis users.

Time for the first reality check because this one is a bit obvious. It may be true that this is the first time anyone at Bristol University has looked into the effects of cannabis on the brain (although that’s unlikely), but it is certainly not the first ever study. For example UKCIA attended the two “Cannabis and Mental Health” conferences held in London in 2004 and 2007, you can see the reviews of them in the library section. One of the more interesting presentations (for me) came from Dr Zerrin Atakan who was involved in a research project which finally reported in 2009, a short review of it can be seen here. The study undertaken by Zerrin Atakan and Professor Philip McGuire consisted of giving subjects a dose of THC or CBD or a placebo and examining the effects on the subject by both a series of standard tests and also by magnetic resonance imaging of the brain.

Professor Philip McGuire concludes, “These studies show that THC and CBD have distinct effects on brain function in humans, and these may underlie their correspondingly different effects on cognition and psychiatric symptoms. Determining how the constituents of cannabis act on the brain is fundamental to understanding the role of cannabis use in the aetiology of psychiatric disorders.”

This was a study carried out on humans note – not rats. So it is simply not correct to claim that this study from Bristol was the first to look at the effects of cannabis on the brain. It’s also worth noting at this point that cannabis is not a single drug, but a combination of several; most noticeably THC and CBD and that these affect very different parts of the brain in very specific and different ways.

We are told of the Bristol study

They found the drug disrupts the same parts of the brain as the psychotic illness, those associated with memory and decision-making.

Now of course, they “found” no such thing. It is no secret that some of the effects of cannabis appear similar to forms of psychosis, hence the term “psychedelic” to describe the family of drugs cannabis belongs to. It is, of course, these effects people seek out when they decide to use cannabis; it changes perception of space and time for example, making decisions can become difficult and so on. Indeed, some of the less pleasant effects cannabis can induce, such as bouts of paranoia (albeit short-lived) resemble forms of psychosis.
Actually, the total reverse is true; the scientists did the study because the effects of cannabis seem to mimic some aspects of psychosis.
The report then claims
Cannabis abuse has previously been linked with increased rates of schizophrenia but this is the strongest evidence yet that the drug mimics its effects.
Note the use of the word “abuse”. The claim that cannabis is “linked” to “increased rates” of schizophrenia is actually not true, the rates of mental illness have remained pretty constant over the decades (the famous and oft quoted Keele study is just one which shows this). If there has been no increase in rates of schizophrenia, cannabis cannot be linked with increased rates of the illness. However, as we’ve noted, the fact that cannabis mimics the effects of the illness are well understood.
Now we get the most important falsification in the report:
The scientists studied rats who had been given the active ingredient of cannabis – in a similar dose to a person smoking a joint.
CP55940 molecule

CP55940 molecule

The scientists did study rats, but they did not use “the active ingredient of cannabis” and it wasn’t given in “a similar dose to a person smoking a joint”. The chemical used was CP55940, a chemical manufactured by Pfizer. According to several websites it is far more potent than THC, SantaCruz Biottechnolgy describe it:

The pharmacological and toxicological properties of this product have not been fully investigated. Exercise caution in use and handling. This product must not be used in humans.

So the study did not use cannabis, or even any of the constituents of cannabis and for this reason alone it seems difficult to justify the claim that the dose used was equivalent to one joint. Indeed it is impossible to compare doses in such a direct way, but if we wanted to try Wikipedia has this to say about CP55940:

CP 55,940 is 45 times more potent than Δ9-THC

And a comment from Ed in Belfast to the Daily Mail article made this calculation:

The compound used is known as CP99540 (45 times stronger than THC, see wikipedia) – starting with a dosage of 0.30 mg per kg. If I weigh 10 stone, roughly 63 kg, I would be given a dosage of 18.9 mgs of CP99540. Given the compound is 45x stronger than THC, this means I would mean I would have to take, relatively speaking, ~850mg of THC. That essentially means 85 joints at once [at 10mg per joint], and that’s just to begin with.

Maybe. Anyway, we are then told

Using electrodes embedded into their brains – which cannot be done in humans – they found those who had the drug were ‘significantly impaired’ in carrying out tasks for up to two hours afterwards.

If this dose of cannabis has the same effect on humans, just one joint could significantly change their behaviour.

This sort of animal experimentation is quite objectionable to many and is certainly very cruel. Quite how much the results of the study can be extrapolated to humans is also questionable. But there again, if a human did ingest 85 joints all at once he probably would be ‘significantly impaired’, or at least he would expect to be.
The rest of the article quotes the authors of the study and makes some claims about the increased risk of mental illness cannabis use is claimed to pose which can easily be challenged, but as far as inaccuracy goes they pale into insignificance with the fact-less basis of the first part of the report.
According to Peter Reynolds of CLEAR who has spoken to Dr Matt Jones
He told me that he was “disappointed but not surprised” at the Daily Mail coverage of the study. He also authorised me to quote his exact words in saying “The study does NOT show that one spliff will bring on schizophrenia”.

Peter Reynolds has made a formal complaint to the Press Complaints Commission about this item, which can be seen here. I spoke to the PR department of Bristol University who were “angry” with the way the Daily Mail reported this study. The report is a work of fiction, totally and utterly baseless lies.

The Daily Mail is, without doubt, a very influential publication which politicians are clearly very scared of. That is can so evidently distort and misrepresent news stories like this is a very real cause for concern. This wasn’t simply a case of sloppy writing from a journalist who couldn’t be bothered to check his or her facts, it was a deliberate set of lies designed to further the Daily Mail’s anti cannabis law reform agenda. It is only the latest in a long line of examples of such distortions from the paper.
The rats, it should be noted, made a full recovery within a couple of hours.