Glyphosate

Given my previous post, 'Hate Mail', I appreciate the irony of getting involved with such an emotive issue. The use of glyphosate, and its links with cancer, create polarised opinions. Here is my attempt at being balanced and neutral...

There's been a lot of chatter recently about the decision by the French Government to ban the direct sale of Roundup (and possibly other glyphosate products) in garden centres. This decision, based on studies of farm workers, has been hailed by many as a step in the right direction... but is it?

In small doses glyphosate isn't particularly dangerous compared with other pesticide products. Jet5 is a disinfectant approved for organic use, but get a small drop of it on your skin and your skin will go white and give you a very unpleasant burning sensation for several hours, and if you breathe in a fungicide like Roseclear (or trade versions) you can have breathing difficulties (add this to something like even mild asthma and you're in trouble).

The problems come from overuse; glyphosate is popular because it's a convenient way to kill weeds without resorting to physical methods like digging. Because it's easy for people who can't be bothered to control weeds in other ways it's become the go-to product for gardeners, but gardeners seldom fully appreciate the importance of things like spraying intervals or dose rates (I had a customer who used Clinic Ace (glyphosate) at 10x dilution rate because she didn't want to wait a week for the weeds to die!). If a home gardener doesn't see results quickly then they spray again and again and again until they get the desired effect, but also causing a pollution problem. Trained pesticide handlers know how to use these products while minimising environmental damage, but the public seem unwilling to take advice/training or even to accept that when they reach for any pesticide product they're entering into a legally binding agreement to use the product safely and exactly how the manufacturer tells them to. This, I'm afraid, really should be the number one reason for taking glyphosate off the shelves; not enough gardeners can be trusted to use herbicides or any pesticide properly at home. A dose of herbicide sprayed at the right time will kill troublesome perennial weeds and leave you with easier to manage seedlings to deal with, but you have to use it properly, and not just reach for weedkiller every time you see a weed.

In agriculture the reliance on glyphosate is even greater; as well as controlling weeds on ground before crops are planted, glyphosate is sprayed onto certain crops to kill them and dry them out. In many cases these weedkilled crops are destined for us, particularly corn and soy. How crops can be sprayed just before harvesting but somehow supposedly not contain glyphosate is beyond me; there is fairly conclusive evidence that glyphosate is getting into our food via these treated crops. Given how much agriculture relies on glyphosate it's not really a surprise that an EU study found higher than average rates of cancer in farm workers- even if the person spraying the crops is in a top of the range sealed cab and is protected from the product, the minute he or she works with the crop directly the dose rate will go straight up!

Given how massive the use of glyphosate is in agriculture I really doubt that normal horticultural use would generate even remotely similar results to the EU study but, as with so many other things like radiation or smoking, a regular large dose of glyphosate probably will put you at higher risk of cancer. I really doubt that horticultural contractors are particularly at risk because the amounts we use are tiny compared to those used on farms (it stands to reason that someone coming into contact with glyphosate sprayed by the hectare will be at significantly higher risk than someone who sprays a few square metres!), but I think controlling the access that gardeners have to pesticides is probably wise, especially while so many people remain ignorant of the dangers of misuse and their personal responsibility to the environment. 

Contractors aren't beyond reproach; I've been surprised by how many professionals I've seen over the years spraying in windy weather, when rain is forecast (and in one case even when it was raining!); we've had our training and really should all be sticking to it!

In due course there will be alternatives to glyphosate for garden use; citronella oil is available in some cases for weed control (although Canada has banned some citronella products so there may be problems there), and 'hot foam' treatment of weeds looks promising, if currently expensive) for larger areas. In the meantime it looks as though glyphosate will remain the dominant chemical weed control, but whether or not it remains in the public domain only time will tell.