Pontifications on Poison
Being some ramblings on events associated with poisonous plants.
Thursday 3rd November 2011
I caught up with a radio programme about fungi that was broadcast a few days ago and there were a couple of things that I thought were worth noting.
The programme itself was a bit like a trip back to the past of radio. You may have heard extracts from science programming in the ‘50s where the idea is to give the impression of a conversation but the novelty of the medium to the participants makes the delivery stilted so that it is quite clear that a written script is being followed.
Mostly, the familiarity with the medium means that, where this type of structure is still used, and it is much less frequently employed these days, it is unobtrusive. Melvyn Bragg’s long-running series ‘In Our Time’ employs this structure but Bragg has the skill to use it without it imposing itself on the listener.
Sadly, that is not a skill possessed by every presenter and, if I hadn’t been so interested in the topic, I would have found it hard to stay the course without being distracted by the structure.
Still, as I said, there were a couple of things about fungi that interested me. The programme was trying to get across how important fungi are to life on earth and establish the major types and their life cycles all in under thirty minutes so it is not surprising that a lot of information was missed out.
Partly because it is one of the easiest to identify, Amanita muscaria featured in the discussion. The programme was being recorded in front of an audience which was asked to identify a number of well-known mushrooms. Amanita muscaria was, of course, one of these and the presenter asked people if they knew any stories about it. I suspect there was a lot of editing because the only two stories broadcast were that Vikings used to eat it before going to war and that people cut it up and put it in milk to kill flies, hence fly agaric.
I was disappointed that none of the experts on the panel took that latter story back to its origins. It came across as though someone had decided to cut up the cap and see if it killed flies whereas, as I’ve mentioned before the way the cap turns up to make a natural bowl that would fill with water and kill flies that were attracted to it was what led people to use it in the manner given by the programme. The important point missed by the programme was that the discovery of its ability to kill flies was made by people looking around them and trying to understand and make sense of the natural world.
That’s an absolutely core part of what makes us what we are and I would have hoped a modern science programme would have got that point across.
In the broadcast version, the subject of Viking ‘berserks’ was also not pursued and, in fact, no mention was made of the psychoactive effects of Amanita muscaria at all.
But the other part of the programme that interested me was learning something new about Taxus baccata, yew. Yew is one of those plants that people focus on because of its medicinal properties. Some people will not make the connection between chemotherapy drugs and poisoning and wonder how yew can be poisonous when it provides a beneficial medicine.
During my time at the Alnwick Garden, there was a lot of attention being paid to Taxus baccata because the breast cancer chemotherapy drug, paclitaxel, is made from taxol a substance obtained from the tree. Large gardens, including Alnwick, would pass the prunings from the extensive yew hedges to a processing company for the taxol to be extracted.
This was a costly process and the amount of paclitaxel produced was, of course, directly linked to the availability of yew clippings. What I learned from listening to the programme is that it has been discovered that the taxol is produced, not by the tree itself, but by a fungus that lives throughout the tree. This means scientists have been able to develop a process for growing the fungus outside the tree and paclitaxel can be produced in whatever quantity is required and at reduced cost.
So, many more women around the world can have their breast cancer treated with drugs rather than surgery and all because, as the programme didn’t point out with Amanita muscaria, the human race looks around and tries to understand how the world works.