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Pontifications on Poison

Being some ramblings on events associated with poisonous plants.

Sunday 25th August 2013

I feel quite a strong pull to suggesting you don’t waste your time reading what follows. I wondered if I should waste my time writing it but concluded that I needed to get my thoughts down on paper.

Last night BBC2 broadcast ‘America's Stoned Kids’. Until the end of August you can watch it on the iPlayer and after that text information and a short clip will still be available. The programme was billed as clinical psychologist and addiction expert Professor John Marsden looking at the likely impact of Cannabis sativa, marijuana, legalisation on teenage use in Colorado.

Prof Marsden has fronted programmes about drugs before and been criticised for relying on anecdotes without offering the science. Knowing that, I decided to watch it on the iPlayer rather than live so I could pause it if I needed to scream in frustration rather than missing parts. I may have given myself the world’s strongest pause button finger as a result.

Cannabis sativa, marijuana

As so often happens with TV programmes about drugs the underlying premise was that all drug use equals abuse. There was no mention that the overwhelming majority of people suffer no long-term ill effects from their use of Cannabis.

Marsden interviewed one of the people behind the campaign to get proposition 64 (which became amendment 64 once voted for last November) passed and was at pains to stress the financial backing for the ‘pro-pot’ case. He said that the campaign spent $2m whereas the anti-campaign only spent a quarter of that. Now, $2m doesn’t seem like a lot of money to me in the world of political campaigning and, of course, the ‘anti’ argument was being made by local and federal government so was getting much more than $500k worth of promotion.

Turning to use by young people, Marsden excelled himself in terms of placing anecdote over evidence. He spoke to two high performing high school students who told him that, in their estimate, 25% of their peers were using cannabis daily. You might have expected a scientist to point out that the US National Institute on Drug Abuse (NIDA) found in its Monitoring the Future survey for 2012 that ‘6.5 percent of high school seniors smoke marijuana daily’.

Next, he went to see a Dr Riggs to find out what this use might be doing. She focussed on the New Zealand study that reported reduced IQ for people who consumed cannabis from an early age. There was no mention of the debate about that finding suggesting that factors other than cannabis use weren’t fully accounted for. You’d hope scientists would acknowledge that the world is very complex but, maybe, the confines of a programme’s agenda makes that hard to do.

Cannabis sativa, marijuana

I should say that I wasn’t always screaming in frustration. Sometimes things were said that spilled so far over into the surreal that the only reaction was to laugh out loud. Dr Riggs concluded her contribution that cannabis was bad, bad, bad by saying ‘something should be done’ because, as we all know, there have been no attempts to control the use of cannabis over the past 40 or so years.

Marsden then went to talk to a grower who has been supplying the ‘medical marijuana’ market and spoke about plans to increase output next year when Amendment 64 comes into effect. Marsden’s voiceover at the end of this segment said ‘No-one knows quite what effect this increase in supply will have on the people of Colorado.’ He offered no evidence that the shift from illegal to legal supply will result in a net increase in availability. And, of course, suggesting that an increase in supply must result in an increase in use is not the way markets work.

In the world of TV documentary as entertainment you must, of course, introduce some jeopardy. Thus Marsden ‘Hit the road’ to drive 100 miles on a fully serviced freeway. Oh please!

I won’t be complaining to the BBC about this programme because I know their response will be to point to the ‘balance’ where Marsden spoke to parents who support the change in the law and set out their vision for a controlled market based on educated choice. And that was good but to make the ‘What do they know?’ point, he went from there to a senior police officer in Denver who spouted the gateway argument and wasn’t challenged on that. (Later on, Marsden spoke to people hoping to build legitimate businesses with publicly traded shares based on producing legal cannabis. Is it likely that these people would risk everything by trying to move users onto other substances?)

Maybe Marsden didn’t have enough time to meet former law enforcement officers who actively campaigned for the change in the law or maybe their position didn’t fit the agenda.

From law enforcement to a treatment centre for teenagers but without making the link between the two. It is hard to know for sure but some teenagers will enter treatment as a way of avoiding sanction under the criminal justice system. Figures for the number of teens being treated for problem use that don’t try and identify those who have, in effect, been coerced into treatment are meaningless.

Cannabis sativa, marijuana

The man in charge of the centre claimed that higher THC leads to faster dependence. If you accept that point, the obvious answer is to have a regulated market with known and controlled strengths.

Marsden moved onto a manufacturer of foods containing cannabis for medical users who don’t want to smoke often because they don't want to feel intoxicated.

In a voiceover, he stated ‘Eating marijuana rather than smoking it allows more of the active ingredient THC to be absorbed into the body’. That seems to be about the most misleading statement in the whole programme. Ingestion of cannabis takes much longer to produce effects of intoxication and the levels of cannabinoids in the blood do not reach those of smoked cannabis. For example 'Absorption from an oral dose of 20 mg Δ9-THC in a chocolate cookie was described as slow and unreliable’. A teenager looking to get stoned is unlikely to turn to cannabis foods with no certainty of when the effects will be felt or what they will be.

The slower effects result from the need for the ingredients to pass through the liver before reaching the blood and that leads to another disincentive to ingestion. Ingested cannabis will result in higher levels of metabolites in urine meaning drug tests are likely to produce a worse result. Given that use by under-21s will remain illegal, drug testing for under 21s is likely to remain an enforcement strategy so it is highly unlikely that teens will intentionally opt for ingested cannabis.

Cannabis sativa, marijuana

There is a problem with accidental ingestion by children who find their parents’ foodstuffs around the home but that problem is no different from that relating to alcohol, tobacco, cosmetics and cleaning materials.

The closing minutes of the programme gave two clear examples of why these sorts of broadcasts add nothing to sensible debate about the issues. The first was the use of over-dramatic language. Marsden said ‘When the impact of legalisation hits next year’. ‘Hits’? The inference is that, on 1st January 2014, there will be some catastrophe resulting from the legislation. The reality is that it will take some time, and careful scientific study, to establish the outcome of this change in policy and the unknown factor is federal reaction that could easily distort the effects.

But the final remarks really damage the reputation of science in general. Marsden acknowledged that there are powerful arguments that prohibition hasn’t worked but didn’t begin to identify them and went on to say ‘common sense’ says legalising sends a message that it is acceptable and that will increase consumption. On the basis of this ‘common sense’ he concluded that there is a ‘real risk’ that more and more will be using at a younger age.

When a scientist prefers ‘common sense’ over evidence we have sunk to a new low.

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