Next Thursday’s referendum on whether to Remain or Leave won’t be the only high-stakes vote to take place in Europe that day. It’s also the date when European member states vote on whether glyphosate - the controversial herbicide - is granted a new licence for use across the EU.

Glyphosate is the main active ingredient in Monsanto’s bestselling weedkiller Roundup, along with a host of non-branded products that do the same job, and it’s a major tool in the armoury of arable farmers (and a fair few gardeners) across the world.

Whether used on a farmer’s oilseed rape crop or a suburban lawn, glyphosate kills weeds - but it has also been described as a potential killer of people, with WHO’s International Agency for Research on Cancer (IARC) stating last year it was “classified as probably carcinogenic to humans”, although this accusation has also been levelled at products such as coffee in the past.

“The delays in its reauthorisation have highlighted how vulnerable Europe really is when it comes to pressure from NGOs”

This position has since been challenged by the likes of the European Food Safety Authority, while the European Chemicals Agency (ECHA) will report its own findings on the herbicide next year. In the meantime, glyphosate - and whether it will get a new licence - has become a highly charged and politically loaded topic.

The chemical’s current 15-year licence expires at the end of this month, and to date no decision has been made on whether it will be granted a new one, with votes postponed and decisions delayed amid growing clamour for its banning.

The European parliament voted in favour of a seven-year extension in April for professional use only, but ultimately the final decision on glyphosate’s future will rest in a vote by member states in a special meeting of the EU’s Plants, Animals, Food & Feed committee on 23 June. The European Commission, which has the power to unilaterally impose a decision, is believed to want member states to have the final say.

Germany, France, Italy, Greece, Austria, Portugal and Luxembourg all abstained during the committee’s previous attempt (on 6 June) to extend the licence, while Malta voted against proposals.

The UK was among 20 member states that voted in favour of a licence renewal, but a qualified majority of 55% of member states was not achieved.

If member states fail to reach a qualified majority on 23 June, campaigners warn of a “potential disaster for farming” with future food supplies potentially affected and prices increasing as yields fall. Opponents, on the other hand, say there are perfectly viable alternatives to glyphosate available, while questions remain over its long-term health risks.

“Robust scientific evidence”

Both sides make powerful claims. The use of glyphosate is worth €633m (£502m) a year to the UK arable sector, says Nick von Westenholz, CEO of the Crop Protection Association, which represents the agrichemical sector. Citing research by consultancy ADAS, he says the loss of glyphosate would “reduce UK production of winter wheat and winter barley by 12%, oilseed rape by 10% and require 49% more man hours per year for crop establishment”.

Glyphosate has more than 40 years of “robust scientific evidence” confirming it poses no unacceptable risk to human health, argues von Westenholz. “It’s unfortunate the debate around glyphosate has become politicised, causing some to lose sight of the overwhelming scientific evidence,” he says.

“Failure to relicense glyphosate would be contrary to the science, provide no benefit to human health, wildlife or the environment and at the same time undermine our ability to produce a safe, affordable supply of food.”

On the other side of the debate, the Soil Association is among a host of NGOs fervently opposed to a licence renewal for the herbicide, while Greenpeace said earlier this month extending the licence in the face of evidence it could cause cancer was like “smelling gas and refusing to evacuate to check for a leak”.

“It’s unfortunate the debate around glyphosate has become politicised, causing some to lose sight of the overwhelming scientific evidence”

Soil Association policy officer Georgia Farnworth contests the CPA’s claims that crop yields could fall without the use of glyphosate, and suggests “there are other alternatives available to farmers to manage and reduce weeds”, noting organic farmers are already controlling weeds without any herbicides whatsoever.

“A ban on glyphosate may also provide an incentive for more research and innovation to develop new technologies and techniques,” she adds.

With two such opposing views, the NFU says there is a need for “new thinking” on how the farming industry as a whole lobbies on plant protection products in the face of a determined group of environmentalist campaigners.

“Glyphosate is a game-changer,” says NFU vice president Guy Smith. “The delays in its reauthorisation have highlighted how vulnerable Europe really is when it comes to pressure from NGOs.”

Smith adds there is more the NFU and its partners can do to up its game “ahead of what looks like a very uncertain future for protecting crops”, and an added complication comes with the EU referendum.

“If Britain remains a member state then working together with [European farming organisation] Copa-Cogeca, other member states and their farming unions will become much more of a focal point. If Britain leaves, then the focus will shift to ensuring government resources its own Chemicals Regulation Directorate sufficiently,” he says.

Just like the result of next week’s referendum, the outcome of the glyphosate vote may not be the last we hear on this topic.