Fludioxonil

also see immune, Polyfluorinated pesticides and PFAs 

Chemical formula:   C12H6F2N2O2

Common Fungicide Causes a Decrease in Antioxidant Responsible for Defense Against Diseases like COVID-19   (Beyond Pesticides, October 8, 2020) Research from the University of Wisconsin—Madison (UWM), suggests that fludioxonil—a commonly used agricultural fungicide—decreases the human body’s ability to defend itself against illnesses, like COVID-19, and promotes disease permanency....a pesticide-induced reduction in the antioxidant glutathione could be responsible for this lack of bodily defense against disease.Although previous studies report that fludioxonil disrupts hepatic (liver), endocrine, and neurological systems, the mode of action by which this fungicide causes these issues only recently came to light. 

Widely Used Fungicide Found to Adversely Affect Enzyme Common to All Cells   (Beyond Pesticides, July 5, 2019) 'This is a story about a chemical pesticide, a fungicide, in wide use for which the mode of action, i.e., the ability to cause harm, has not been fully understood. It is not a story unique to this pesticide... The ability of the fungicide fludioxonil to act on a sugar-metabolizing enzyme common to all cells, and to produce the damaging compound methylglyoxal, may mean that the pesticide has more potential to harm non-fungal cells than previously thought.'   'Fludioxonil, a phenylpyrrole fungicide, which was developed to treat seeds during storage. However, it has come to be used commonly on grains, vegetables, fruits, and ornamental plants during cultivation, and worse (more on this below), to treat produce after it has been harvested to extend “shelf life.” Though fludioxonil is effective in killing fungi, the mode, or mechanism, of action for this pesticide was previously not well understood. 'Dr. Brandhorst notes, “The take home lesson is that fludioxonil is multifactorial. It’s not compromising cells by one solitary mechanism. It has potential to damage cells in a variety of ways.”'

• Fludioxonil persists in soil — near the surface for weeks, and for years if it ends up deeper in the soil, 
• it is also a “super toxin” for earthworms.
• The fungicide’s extensive post-harvest use on food crops is of particular concern because it eliminates break down mechanisms 
• the waxy fungicide is not easily removed by rinsing.
• Further, UV-vis treatment of produce (which is sometimes done to reduce pathogens on fresh fruits and vegetables) actually significantly increases the toxicity of fludioxonil.
•  is an EPA Category I toxin — “highly toxic and severely irritating” — to aquatic plants, bacteria, insects, fish, and aquatic invertebrates
• “there is also reason to believe that breakdown products of this pesticide may be 100 times more toxic than fludioxonil itself.”
• Synergistic potential. 'A 2012 study by French researchers found that a mixture of fludioxonil and cyprodinil, another fungicide, yielded data suggesting cytotoxic (lethal to cells) and genotoxic (damaging to DNA)' 

Neither the US EPA or the PMRA comprehensively evaluates pesticides for synergistic effects. 'In 2016, the Center for Biological Diversity wrote an extensive report on this issue: Toxic Concoctions: How the EPA Ignores the Dangers of Pesticide Cocktails.' 

SNAP Comment: There are currently 39 fludioxonil products registered in Canada as of 20 July 2019. Several are in combination with other pesticides. In addition ot seed and potato seed treatment, some formulations are used on leafy vegetables like spinach, fruit and vine climbing crops and turf in golf courses. I did not do an exhaustive search of all labels. This looks like an emerging problem, perhaps the next glyphosate?