Glyphosate has been much in the news of late and the calls to ban it are increasing in this country. I am no scientist so any opinions we have here are based on experience and observation. Because we ran a plant nursery for about three decades, our experience with sprays is greater than the average home gardener. You don’t think all those brilliant looking plants you buy from the garden centre are grown organically, do you?
Because of my lack of scientific background, I was pleased to find a post on the credible and independent Sciblogs site, written by scientist, Dr Grant Jacobs. If you have any interest in the use of glyphosate, I would urge you to read it in full here.
If you are not going to read it in full, the key points I have taken from it are:
- The original probable (not definitive) link between glyphosate and cancer was made by IARC in 2015 (IARC being the International Agency for Research into Cancer which comes under the World Health Organisation). IARC’s role is to flag areas for further investigation and identify hazards, not to make definitive rulings. Even the term ‘probable link’ is an oversimplification of IARC’s findings.
- The role of risk assessment on those potential hazards falls to regulatory bodies – the Environmental Protection Agency is a key body in NZ. And while IARC made the initial finding, subsequent investigations by scientists in such regulatory bodies around the world have not raised red flags. It appears that all such investigations have cleared it as safe when used according to instructions and with usual safety precautions. The difference between hazard and proven risk is important.
- Any blanket ban on such a product comes down to a political decision and that is what we are seeing happening in Europe. A political decision is not necessarily based on science. It can often be based more in public opinion and political polling.
- The court case in USA which triggered the recent round of debate (the school caretaker who contracted cancer) is based on a judge and jury trial in a courtroom and as such it is subject to the vagaries of a court system where the jury may or may not understand the science and where the directions given by the judge have a huge influence. This will all be tested further in the appeals process but a court case does not constitute rigorous scientific enquiry and risk assessment. While the case is certainly interesting, it is not proof of anything at this stage.
Jacobs also clarifies why we need to be talking ‘glyphosate’, not using the original brand name of Round Up. Indeed Round Up for Lawns contains no glyphosate at all. It is the chemical that is under scrutiny, not the branding. Round Up is a Monsanto product and while there are many concerns about Monsanto across a whole range of issues, the safety or otherwise of glyphosate should not be confused with a battle against Monsanto business ethics (or perceived lack thereof). Let us keep the arguments separate.
I was listening to a discussion on Radio NZ about all this and the host went on and on about the safety of glyphosate. “Is it safe? Can you guarantee it is safe?” he kept asking. Wrong question. How safe is it if used properly? Is the risk within acceptable limits? These might be better questions. Our lives are filled with hazards that we choose to manage. In the 44 years that glyphosate has been in use, it has proven itself to be safer than many other chemical sprays that are, or were, also used. Remember Paraquat? I don’t think there is any dispute that glyphosate is hugely safer than Paraquat but is it safe enough to continue using?
I worry about the nature of public debate that may see political decisions to ban what has so far been a relatively safe agrichemical, while leaving far more dangerous options on the market. Unless we have a change of heart, mind and practice on how we manage weeds and pasture, we run the risk of banning one option, only to have people substitute with another spray that could be way worse. We are a country that accepts a pretty high level of use of chemicals, toxins and sprays. While some are now controlled and you need to be an approved handler to buy them, the home gardener can still buy a fair number of products across the counter that are no longer available to their counterparts in the European Community.
The issue of the possible threat to human health underpins all this debate with IARC, cancer and banning glyphosate. It is separate to the issue of the impact on ecological systems. That is a whole different area to be considered. There are theories that environmental damage may be more to do with the surfactant (the sticking agent) rather than the glyphosate. We have also raised our eyebrows at the quick knockdown glyphosate products – the convenient aerosol or pump sprays that the home gardener can use to kill a plant more or less instantly. But again, that is a separate issue to fundamental matter of the claimed threat to human health.
It is complicated, not black and white. By all means, go organic and shun the use of non-organic sprays in your own garden. But maybe don’t cast glyphosate as the greatest villain of all the sprays and single it out for blanket bans while leaving the others on the market. I think that is called throwing the baby out with the bathwater.
Time will tell if we will face a future without glyphosate and that bears some thinking about for home gardeners, farmers and most landowners as well as the public sector which maintains the parks, reserves, road verges and playing fields. Our attitudes to weeds, to invasive plants, to long grass and to presentation standards which are widely held as desirable will have to change too. On the bright side, the scourge of the scorched earth roadside may disappear which would be hugely beneficial both environmentally and aesthetically, in my opinion at least.