A new scientific analysis of toxicity data for the fungicide fluazinam has raised fresh concerns about how pesticides are evaluated in Europe. Researchers found that harmful brain development effects were hidden during the approval process.

A new study by researchers at Stockholm University has identified weaknesses in the regulatory assessment of the fungicide fluazinam, which raises broader questions about how pesticide safety studies are evaluated within the European Union. The researchers argue that false statistical reporting and regulatory oversight allowed evidence of developmental neurotoxicity to go unnoticed during the pesticide’s approval process. The findings arrive as fluazinam is undergoing EU renewal assessment, and as policymakers debate reforms to the EU’s chemical and food safety legislation

New scientific analysis of Fluazinam toxicity data

The researchers revisited a developmental neurotoxicity (DNT) study originally commissioned by the pesticide manufacturer before fluazinam was approved for use in the EU in 2008. Using the original study data, they identified six instances of incorrect statistical reporting that, according to their analysis, obscured significant effects on brain development in rat offspring. Their re-analysis identified significant adverse effects on brain weight and brain dimensions that they consider biologically relevant for regulatory decision-making. The study is currently available as a preprint while undergoing peer review.

Beyond the statistical analysis, the authors report that the developmental neurotoxicity study was not initially submitted during the EU approval process and only became available to regulators after it was specifically requested years later. They also argue that subsequent regulatory reviews did not adequately investigate the reported concerns, despite being informed of potential issues with the study’s interpretation.

Implications for pesticide regulation

According to the researchers, the fluazinam case reflects broader structural challenges within the current regulatory system. Under existing procedures, manufacturers commission many of the toxicity studies used to support pesticide approvals. The authors argue that this approach creates an inherent conflict of interest and places considerable demands on regulatory authorities to independently verify complex datasets and statistical analyses.

The timing of the findings is particularly relevant because the European Union is currently discussing the proposed Food and Feed Safety Omnibus package, which aims to simplify aspects of chemical and food safety legislation. Rather than reducing regulatory requirements, the researchers argue that the fluazinam case demonstrates the need for stronger oversight, greater transparency, and increased resources for authorities responsible for reviewing industry-generated studies

Looking ahead

Fluazinam remains under evaluation as part of its ongoing EU renewal process. The European Food Safety Authority (EFSA), together with Member States, is reviewing the new analysis and underlying data before reaching conclusions on the substance’s future approval status. Researchers have also published a policy memo outlining recommendations to strengthen the pesticide approval system, including greater independent scrutiny of industry-funded studies and improvements to regulatory oversight.

As discussions on the future of EU pesticide regulation continue, the fluazinam case serves as a reminder that robust scientific assessment depends not only on generating high-quality data, but also on transparent reporting, independent evaluation, and regulatory systems capable of identifying and addressing potential risks before products reach the market.

The publication (preprint): https://zenodo.org/records/21069500

Official press release: https://www.su.se/english/divisions/stockholm-university-baltic-sea-centre/news/articles/2026-07-02-scientists-warn-systemic-failures-allow-hazardous-pesticides-to-be-approved—stricter-oversight-urgently-needed