Cortinarius caperatus found to be infested with maggots when picked. Mycologist David Arora recommends discarding the tough stipes. The popularity of "C. caperatus" across Europe has led to safety concerns related to its propensity to accumulate contaminants. Fungi are very efficient at absorbing radioactive isotopes of caesium from the soil and naturally have trace amounts of the element. Caesium may take the place of potassium, which exists in high concentrations in mushrooms. "C. caperatus" bioaccumulates radioactive caesium Cs—a product of nuclear testing—much more than many other mushroom species. Levels dramatically rose after the 1986 Chernobyl disaster. This is a potential health issue
Radiation effects from the Fukushima Daiichi nuclear disaster tests were available. On 16 November 630 becquerels per kilogram of radioactive caesium was detected in rice harvested in the Oonami district in Fukushima City. All rice of the fields nearby was stored and none of this rice had been sold to the market. On 18 November all 154 farmers in the district were asked to suspend all shipments of rice. Tests were ordered on rice samples from all 154 farms in the district. The result of this testing was reported on 25 November: five more farms were found with caesium contaminated rice at a distance of 56 kilometers from