When does a plant become poison? Our Chemical Romance…
Maybe I’m weird.
I can’t help but look at a plant and wonder about its chemistry and in particular, how I can extract it…
I wonder if it is nature or nurture that has made me this way.

Did I get trained to see each plant not only as what it is as a discrete and knowable thing and what it is as part of an ecosystem but also what it could yield if only its chemical potential was unleashed? As a child I was always encouraged to think scientifically and test out my ideas so it could logically be assumed that I’ve developed a skill in this area. However, I still wonder if there is more to it, could my ability to ‘see’ a material from a chemistry perspective be in-printed on my DNA? Could this thing way of viewing the world that we now think of as elite, niche, somewhat detached and synthetic actually be inherently human…
If I’d have pondered these thoughts twenty or so years ago, I’d have most likely concluded that my perspective was one that I’d had trained into me. These days I’m more likely to lean the other way especially now, in an age when I and many others like me are quite literally questioning everything.
I guess I was lucky, my mum wove her love of the outdoors, of gardens and bushland, fairies and forests into my heart. Some of my most vivid memories of childhood involved trips to local woodland with my mum and her brother (my uncle). We spoke of how my ancestors would use nettles for soup and soothing itchy skin (I was fascinated by this having both eczema prone itchy skin and a propensity for falling into the nettles and getting covered in itchy stings). How could a plant that itched so much be used to stop you itching? What weirdness was that? I learned how moss was used to line the nappies of babies, how dandelions made you wet the bed and how Milk Thistle strengthened a tired and sluggish liver. I remember being particularly interested in how Foxgloves could stop your heart, thinking ‘how could something so beautiful and innocent looking (and that grew in many a friends garden) be so deadly? I learned of how some mushrooms could ruin your mind forever and make you see things that weren’t there, how buttercups could be used to predict whether you liked butter (OK, so I always suspected this was just a bit of fun) and how four leaf clovers could be a sign that good luck was just around the corner (I did believe this for a long time, probably because I so wanted it to be true).
For me these were not just stories to be accepted, they were theories to be tested. While I was not encouraged to try the mushrooms, I was encouraged to develop my inquiring mind in a way that could find out why, how, when and where these ‘magical’ plant powers came from. I say magic in quotation marks as I’m still surprised at how that word is used. I hear it still, used to describe phenomena that may well either be too hard for one to get their head around or that one consciously chooses not to try and demystify. To be honest I still don’t get the latter as for me the magic comes back ten-fold when you know how a plant or material works either by itself or when in combination with others. It is quite literally genius how chemistry works in the world!
My theory of chemistry being a basic human instinct is built on a series of logical assumptions that have at their basis the fact that I exist today. I am only here now because my ancestors knew how to successfully read and adapt to their environment. My ancestors were clearly not the type of people who chowed down on a Foxglove salad, well, at least not until after they passed on their DNA. Mine, like yours were people who knew the natural world in a way that was far beyond the comprehension of most of us modern folks. While they may not have understood chemistry in the way that the Greek’s of Wikipedia or the Gentlemen of 1600’s Europe deconstructed and reconstructed it, these every-day humans would have had a feel for it in an ‘in your bones’ way that is necessary when you depend on it, not just for your survival but for your ability to thrive!
Our modern narrative of chemistry being a relatively new and elite area of study seems to me to be less and less of an accident when viewed through the 2020 lens. Many popular folk law tales of foods, potions and treatments lead us to assume that no chemistry was done at all prior to the chemical revolution of the late 17’s and early 18th centuries (average Jo type idea) or that the chemistry done was hap-hazard and by accident rather than planned (supporting the ‘primative man’ view of the world, perpetuated by many an archeologist or anthropologist back in the day). I know many people who want to go back to the days when ‘plants were taken whole and then put into a pot or ground up and then voila, you have your thing’. But did that really happen, was that really all there was to it? Were our ancestors really limited to whole foods and whole medicines? For a long while I’ve wondered if the devil has been lost in the detail but now I fear that I it has been lost on purpose. You can’t ‘save’ people who were never lost or enlighten people who never lived in the dark…
Wikipedia is not a good primary source but it is a popular one (note the distinction). As expected, it presents a fairly Eurocentric (or at least Western Hemisphere) view of the origins of chemistry, placing emphasis on the role that Greek philosophy played in our understanding of matter before keeping the bulk of our attention focused on a fairly recent past. While I have no basis on which to dispute or discredit the role that the Greeks or other learned European men (and probably the odd woman) played during this time, I feel that this well-worn track is not the one I need to take if I want to understand the human-chemistry connection on a deeper level. To understand that, I feel I need to go back thousands more years…
The same Wikipedia entry that jumped our brains to ancient Greece begins with a story that’s 100,000 years old, of how caves in South Africa (Blombos) were found to be painted with pigment that had survived this long because of their intentionally prepared chemistry.
The practice of taking natural pigments, usually Ochre, and using it to make paint is the subject of an intense amount of scientific study some of which I’ve read to inform this piece. Ochre is found all over the world and Ochre-based art is likewise, widely distributed. Rather than being a simple single chemical, Ochre is the common name for a whole range of naturally pigmented clays that contain sand (silicone dioxide), kaolin (aluminium silicate) and iron-rich pigments (iron oxides). It is easy to think of these mineral clays as chemically inert (unreactive) but they are not. They can be changed through heating, mixing with a range of binder chemicals, reacting with acids or even using as an acid to react with other materials.
If we just consider the act of using ochre pigment for painting this takes more than just a little digging up of dirt and then applying that to the cave wall. Ash, blood, plant tannins and acids, limestone, Seashells and even other fluids such as bone marrow or cerebral fluids were used to help these pigments apply neater and smoother and withstand the test of time.
Through studying Ochre and the caves in which our ancient ancestors painted, we gain an insight into the rich and complex cultural practices that were in existence thousands of years before us. Our ancestors were not just randomly chucking things into a pot and going – wow, no idea how that worked but yay for me – instead they were fermenting, grinding, distilling, pH changing, pyrolyzing and distilling. These people knew how to make wood burn wood hotter (by producing charcoal), how to change the colour of natural pigments to produce different shades for nuance, effect and context (both through physical and chemical reactions). It is even hypothesised that our knowledge of chemistry helped us to migrate so far by helping us produce the best natural sunscreens! Ochre is still used today for sun protection but again, rather than it just being a matter of rolling around in the Ochre pile, ancient humans consciously prepared their sunscreen taking care with particle size and creating a base to provide both optimal skin adhesion and SPF enhancement-maybe some of my readers could benefit from taking a trip back in time and paying attention to this.
Chemistry requires reagents and as a chemist I often use strong acids or bases change one chemical for another. For example, I use Sodium Hydroxide for saponification and Sulphuric acid to turn fatty alcohols into esters. It would be easy to assume that chemistry proper didn’t exist until these chemicals were available by the bottle load but that ignores the fact that Hydrochloric acid is available in the stomach of the animal you just ate and its cerebral fluid is full of powerful chemicals that can be used for, among other things tanning leather. Then there are the plants including fruits (citric and malic acids) and insects (Formic acid) and pee (Urea). For alkali we have pot ash which is the stuff we get when we burn wood down ash and then let some of the chemicals from that seep into water. The other common reagent for a budding organic chemist is alcohol which is easy to get via fermentation — a chemical reaction humans have been enjoying for millenia.
Chemistry also requires mixing vessels, preferably ones that resist change themselves. Here too we find evidence of intentional choosing based on careful observation and experimentation rather than just good luck or circumstance. Abalone shells were found in that cave in South Africa, they seemed to be the vessel of choice for the Ochre pigment. On the surface of it that sounds unremarkable until you read a little more and discover the Abalone shells are incredibly chemically resistant compared to other seashells due to a particular natural adhesive compound they contain. Now even if our prehistoric brothers and sisters did just happen to live in Abalone Valley, it would be ridiculous to think that someone one day didn’t try using a different shell only to find it dissolved, cracked or otherwise failed in its duty.
I started this piece with a mind to focus on plants and plant chemistry but have ended being on a journey centred on ochre and art. This, I feel, is probably just as well, in fact it may be better than what I originally imagined. My original motivation for writing this was to help me answer my own question ‘when does a plant become poison’. That question came to me when I was browsing my 1949 copy of the ‘British Pharmacopaea’ while trying to separate saponins from pine bark. I had not got the book when I did my experiment and had gone off my own feel for chemistry to come up with a method that seemed by all accounts to work. Acquiring the above by pure fluke really (having spotted it at a soon-to-be-closing-down antique shop) I discovered that the method I’d made-up was about right (yay for me) and that got me thinking about life, the universe and everything…
For me there is no difference between taking a plant and working with it to isolate and concentrate different components and working on Ochre to improve its performance and produce a wider variety of colour options. Both are examples of ‘doing’ chemistry. The main difference, I’ve observed, from a lay-persons perspective is that the former evokes images of anything from Breaking bad drug dealing or lofty towered university dons dressed in white coats through to ancient alchemists obsessed with turning every-day materials into gold while the latter doesn’t feel like we’re talking about chemistry at all. After writing this essay I’m now inclined to believe that our common conception of what chemistry is and who does it are a product of how we’ve chosen to write and read history. I feel that has done our ancestors a great disservice and disempowered us.
So, it is with that thought that I decide I am not weird at all. That I should celebrate my scientifically minded ancient relatives as normal people trying to find the perfect paint recipe by ‘doing’ chemistry and that I should carry on looking at plants the way I naturally do. The evidence does point to it being in our nature to think scientifically and to explore the chemistry of the natural world. This pursuit has helped us express our hopes and dreams and communicate our conceptual understanding of the world around us. We are here today in part because our ancestors found ways to enhance their lives by harnessing the power of chemistry and I’m glad to have inherited eyes that can clearly see that.
Now if only we could broaden the narrative to show everyone that chemicals aren’t a dirty word, that doing chemistry isn’t a modern invention and that being a chemist isn’t just for Europe-centric men in white coats the world would be a better place.
As for the question of when does a plant become a poison, I guess that all depends on what you do with it.
Amanda
Some of the interesting references I used to research this Essay.
Such an interesting article–as always! Really enjoyed it.
Thanks Mary, there’s so many rabbit holes to go down with this story, I could research it for years!