Another week goes by and another study reveals health or environmental risks associated with the use of farm pesticides. This time, researchers at the University of Washington have concluded that a high exposure to glyphosate, the active ingredient in Bayer’s Roundup, ‘may increase’ the risk of contracting blood cancer by ‘41%’.

The research is a ‘meta-study’ which means that, rather than engaging in new scientific research, it is a study of many previous epidemiological studies carried out between 2001 and 2018 to determine the degree to which exposure to glyphosate may increase the risk of non-Hodgkin lymphoma. (These pieces of research include a 2018 study of more than 54,000 people who work as ‘licensed pesticide applicators’.)

A brief trawl through the published paper reveals the complexity of the task of analysing so many different pieces of research. Some of the papers have poignant titles, like: ‘Occurrence of glyphosate and AMPA residues in soy-based infant formula sold in Brazil’. Others are simply disturbing: for example, ‘Excretion of the herbicide glyphosate in older adults between 1993 and 2016’.

The trouble with glyphosate – like so many other agrichemicals – is that it is persistent in the wider environment long after it has killed the weed, fungus or insect that the farmer was targeting. Glyphosate persists in food, water, soil and dust. It’s not even got rid of by baking. Traces of it have been detected in fish, berries, vegetables, baby formula and grains. Basically if you are a human being alive on planet Earth you are going to be exposed to glyphosate, whether you like it or not.

I have been applying glyphosate on my farm just about all my farming career. Initially this was as a post-harvest weedkiller. I then started to use it as a pre-drilling desiccant, and finally as a pre-harvest desiccant for ‘green burndown’. That was the point where, instinctively, even as a farmer I started to worry. Was it really sensible to be spraying my barley with glyphosate only weeks before harvest, just as it was about to be carted off to be made into beer? No wonder, by the mid-2000s, regulatory agencies increased permissible residue levels of glyphosate-based herbicides.

In recent years, of course, glyphosate usage has been taken to ever higher levels through the introduction across much of the world (but not the EU) of GM ‘Roundup ready’ crops. In Britain there has also been an increase in glyphosate use as part of the ‘min-till’ or even ‘no-till’ revolution that has been adopted by arable farmers.

I’ve no idea whether my considerable professional exposure over four decades to glyphosate has increased the likelihood of me contracting blood cancer by ‘41%’ or not. But I think one thing is certain: the evidence appears to be piling up that – at the very least – regulatory agencies should be looking at how glyphosate use can be reduced in ways that have the least effect on farm productivity.