On 19 September 2021, French television channel France 5 unveiled a critically acclaimed documentary2 in which French investigative journalist Martin Boudot seeks to raise public awareness of the dangers of overexposure to cadmium from phosphate fertilizers used in France to produce potatoes - "the favourite crop of the French". Through scientific studies and a series of interviews with politicians, activists and experts, he exposes the urgent need for the industry and government to encourage the use of cleaner phosphates, as evidenced by the ANSES recommendation3 to set a limit of 20 Mg/kg P2O5 on inorganic fertilizers.
Through his investigations, Martin Boudot carried out scientific analyses revealing the toxicity emanating from the presence of cadmium, a heavy metal and carcinogenic substance found in many phosphate-based fertilizers, such as those predominantly used on French potato crops.
In collaboration with Joël Dupont, a heavy metal specialist and toxicologist emeritus at Lariboisière Hospital, Boudot conducted a toxicological analysis of samples of potatoes grown in various departments of France, as well as of the urine of inhabitants of Brittany – a region particularly exposed to contaminated phosphates – with the aim of assessing the degree of cadmium contamination and its impacts on food and human health.
Potatoes and human urine samples exceeding the cadmium limit
The analyses showed that around 65% of the samples exceeded all permitted cadmium thresholds, and that conventional French potatoes contain on average three times more cadmium resides than organic ones. As for the human urine samples, 21% of them exceeded the critical cadmium threshold, above which the health authorities consider that there is a real risk of developing diseases such as osteoporosis or Raynaud's cancer. As Joël Dupont pointed out, there is a direct and real effect between these results and the use of high cadmium phosphate fertilizers on potato crops.
The voice of the National Agency for Health and Food Safety (ANSES)
Martin Boudot's report relates to the ANSES report, which emphasises its firm support for reducing the health impacts of cadmium on the French population, including reducing the cadmium content of potatoes and cereals - the two crops most exposed to high cadmium fertilizers in France.
Jean-Luc Volatier, Director of Food Risk Assessment at ANSES stressed that: “it is necessary to reduce the population's exposure to cadmium, it is really a question of public health priority”.
The ANSES strongly recommended to the French government to drastically reduce the maximum limit of cadmium content in phosphate-based fertilizers3.
French Minister of Agriculture, Julien Denormandie:
"Cadmium is a real danger. We all have an interest in limiting its impact. As soon as the results of the study confirmed the concerns, we started working. A draft regulation limiting cadmium intake, which could be published in the summer of 2021, is under discussion. This is our goal."
Getting rid of cadmium in the fertilizer manufacturing process is achievable
The documentary also contains the valuable testimony of Philip Srapp, a former fertilizer trader, who points out that getting rid of cadmium in the fertilizer manufacturing process is achievable, yet it has been snubbed by the industry for years.
“The problem is that it costs money. We estimate the costs at $10-12 per tonne of product. It's not a big deal, it represents about 3-4% of the total price”.
Philip Srapp also pointed that European legislation needs to be changed not in 2023 or 2025, but tomorrow, because if cadmium enters the soil, it enters the food chain.
What is the solution?
While phosphate-based fertilizers are undoubtedly essential to agricultural practices, this documentary highlights the need to act against overexposure to heavy metals, such as cadmium, for public health and ecological reasons.
Stricter regulation is needed in Europe to meet the highest safety and environmental standards, as defined in the European Green Deal. The implementation of a more restrictive legal limit on the cadmium content of fertilizers would promote the sustainable use of phosphate fertilizers and, indirectly, improve human health, support food safety and encourage sustainable agricultural management.
ANSES, 2019. Avis et rapports de l'ANSES relatif à l'exposition au cadmium (CAS n°7440 −43-9). https://www.anses.fr/fr/content/exposition-au-cadmium-l%E2%80%99ansespropose-des-valeurs-limites-pour-mieux-prot%C3%A9ger-les. Carne, G., Leconte, S., Sirot, V., Breysse, N., Badot, P. M., Bispo, A., ... & Crepet, A. (2021). Mass balance approach to assess the impact of cadmium decrease in mineral phosphate fertilizers on health risk: The case-study of French agricultural soils. Science of the Total Environment, 760, 143374.
ANSES, 2019. Avis et rapports de l'ANSES relatif à l'exposition au cadmium (CAS n°7440 −43-9). https://www.anses.fr/fr/content/exposition-au-cadmium-l%E2%80%99ansespropose-des-valeurs-limites-pour-mieux-prot%C3%A9ger-les.
Carne, G., Leconte, S., Sirot, V., Breysse, N., Badot, P. M., Bispo, A., ... & Crepet, A. (2021). Mass balance approach to assess the impact of cadmium decrease in mineral phosphate fertilizers on health risk: The case-study of French agricultural soils. Science of the Total Environment, 760, 143374.