Experts Discuss Role of Evidence in Cadmium Exposure Debate

France's national agency for food, environmental and occupational health safety, known as ANSES, released a report on March 25, 2026, confirming that reference toxicological values for cadmium were exceeded in a significant number of French people. Children were particularly affected, with food identified as the main source of exposure.

The agency recommended actions on phosphate fertilizers but did not conclude a proven causal link between cadmium and pancreatic cancer. Following the report's publication, a polarized debate emerged. Some doctors viewed cadmium as a plausible explanation for the increase in pancreatic cancers in France.

Others noted that ANSES had not established this link and suggested that claiming otherwise could be seen as activism.

and Mathieu Parenti, experts in agricultural and environmental issues, stated that the polarization stems from a misunderstanding of scientific evidence's role in public health decisions. They noted that each side in health alerts related to chemical exposure claims to represent science and accuses the other of ideological bias.

According to Gaigné and Parenti, the lack of evidence is often interpreted by public authorities and industry as an absence of risk. They described this reasoning as a recurring theme in public health history. Gaigné and Parenti provided examples to illustrate their point.

In 2013, American economist Emily Oster concluded in her book Expecting Better that a glass of wine a day during pregnancy was risk-free, based on data analysis.

in fetal alcohol spectrum disorders challenged Oster's conclusion, pointing out that negative effects appear when children are monitored beyond early childhood and when the spectrum of disorders is broadened. Gaigné and Parenti stated that the absence of findings reflected study limitations, not an absence of risk.

Another example involved hydraulic fracturing, or fracking, in the United States. The industry argued that the process could not contaminate groundwater. In 2017, researchers Janet Currie, Michael Greenstone, and Katherine Meckel reported an increased risk of low birth weight near fracking sites, though they could not identify the transmission pathway.

Five years later, in 2022, researchers Elaine Hill and Lala Ma identified a mechanism involving drinking water contamination. Gaigné and Parenti also mentioned health crises in France linked to chemicals, including chlordecone, where initial absence of irrefutable evidence was interpreted as no risk.

The experts emphasized that complexity in reality often leads to delayed recognition of risks. They argued that such interpretations have had serious consequences in public health history. The debate highlights ongoing challenges in balancing scientific evidence with precautionary actions in environmental and health policy.