The job of the European Food Safety Authority (EFSA) is to assess what might make food unsafe. That’s hard enough. It is even harder when the agency is at the centre of a public debate that goes far beyond science.

This has happened with artificial sweeteners, genetically modified (GM) organisms and glyphosate, the world’s most ubiquitous herbicide. When questions about a society’s values are thrust onto scientific agencies rather than elected officials, scientific assessment suffers.

The glyphosate controversy began in earnest two-and-a-half years ago, when EFSA and experts designated by European Union members concluded that the product is unlikely to be carcinogenic. In late 2017, the European Commission renewed a licence allowing the herbicide’s sale. EFSA’s conclusion contradicted that of the International Agency for Research on Cancer (IARC), which had classified the chemical as “probably carcinogenic” months earlier, bringing its own share of controversy.

That the agencies reached different conclusions is not surprising: each considered different bodies of scientific evidence and methodologies. Other independent assessments — by the European Chemicals Agency and regulatory bodies in the United States, Canada, Japan and Australia — agreed with EFSA. So did an expert body on pesticide residues convened by the Food and Agriculture Organization of the United Nations and the World Health Organization.

Even so, the divergence between EFSA’s conclusion and the IARC’s has been debated by legislators from Brussels to Berlin and beyond. We have seen scare stories about trace levels of glyphosate residues in German beer or Italian pasta — but these fail to mention that observed amounts of herbicide residues would pose risks only if a person consumed roughly 1,000 litres of beer or their body’s weight in dry pasta in one day.

Why the frenzy? Agencies that find low risk of regulated products are often accused of undue industry influence. We at EFSA believe that some campaigners are unwilling to accept any evidence that certain regulated substances are safe, and will tout weak scientific studies showing the opposite. The same groups applauded EFSA for reviews on other pesticides, such as neonicotinoids, that it deemed dangerous.

It seems to us that some campaigners contest the science of safety assessments in pursuit of greater political arguments. These arguments deserve airing — but they belong with policymakers.

In the past two years, EFSA has faced multiple allegations over its evaluation of glyphosate. The most pernicious of these is that the agency violated good scientific practice by plagiarizing information from industry. It is true that the document in question, the Renewal Assessment Report produced by German authorities, includes a section summarizing published toxicology literature that contains text compiled by a committee of some 20 companies, including glyphosate’s original manufacturer, Monsanto. But this is standard practice, and EFSA peer-review panels vetted the material that appeared.

The section brought forward as allegedly copied from industry also highlights concerns over products that contain glyphosate. In fact, it was used to support a recommendation by EFSA in November 2015 to further evaluate the safety of plant-protection products containing glyphosate. This section was made publicly available for comment in 2014, but complaints of copied text by regulatory agencies came in late 2017, after other complaints were raised about Monsanto’s possible influence over published scientific literature.

So, when campaigners allege that EFSA did not follow due scientific process when assessing glyphosate, we believe that they are really railing against bigger issues: the role of modern agricultural practices and multinational biotech firms in our food supply.

A broader societal discussion about these issues is essential, but it won’t be achieved by picking on regulatory science. It is the role of politicians to represent the values, needs and expectations of their constituents through democratic processes. This is outside the responsibility of organizations such as EFSA, which were created to advise EU policymakers on scientific matters.

Three changes would help elected officials and regulatory agencies to do their separate jobs. First, questions about societal values should be framed ahead of and outside scientific work. The EU must equip itself with a legal and regulatory framework for food production that accounts for citizens’ opinions on intensive agriculture, pesticide use, GM organisms and other biotechnology, and the importance of biodiversity. This will provide a forum for open, honest debate.

Second, regulatory and legal guidelines should be drawn up to govern how regulatory bodies interact with industry and handle transparency of the data that they use.

Finally, politicians need to decide whether they are willing to allow risk assessment of regulated products, such as glyphosate and food additives, to continue to be based on safety studies commissioned and paid for by the industry, as has been the case for decades. If so, politicians must have the courage to support the regulatory bodies charged with implementing these rules. If not, they must find funding for these studies elsewhere. Only once these steps have been taken will regulatory agencies be free from allegations of bias when their scientific conclusions are at odds with the political agenda of one interest group or another.