海角社区

Gamma irradiation,听an industry-standard sterilization method for medicinal and recreational cannabis,听does not fully听eliminate听toxic fungi or their chemical residues, a 海角社区 study has found.听Current testing practices may also miss contamination, raising concerns about health risks for vulnerable users, particularly those with weakened immune systems.听

The researchers said this is听especially听significant听given that听70听per cent of cannabis is consumed by smoking or vaping, which听may听deliver toxins directly into听the听lungs听and听exacerbate听smoking-related听injury to lung tissues.听

These听findings听point to a听need听for听stricter testing and better safeguards, they said.

Major health hazards

Gamma irradiation听works by听damaging听the DNA and RNA of听microbes and听degrading听mycotoxins听鈥撎齢armful compounds produced by certain fungi.听While this process significantly reduces microbial loads, researchers found听viable听spores of听mycotoxigenic fungi, DNA fragments听and traces of toxins remained after irradiation.听听

These听remnants听pose听major health hazards, with heightened risk for听such听populations as cancer patients, transplant听recipients听and individuals with HIV/AIDS.听However, the听study听also听cites multiple case reports of fungal lung infections and other opportunistic infections听in听healthy听people exposed听to contaminated听cannabis听products.听

Combined methods听can听improve testing听

Researchers听analyzed听dried听cannabis buds from a licensed producer听and听ready-to-use products听from听a licensed producer听that were听legally听on the market.听They听used听three听complementary approaches:听

• Culture-based methods to grow and听identify听living fungi and bacteria.听

• Molecular tests (PCR and qPCR) to detect fungal DNA and toxin-producing genes.听

• Antibody-based ELISA assays听to听measure mycotoxins such as aflatoxins and ochratoxins.听

The team found that ELISA,听the current industry standard,听is not sensitive enough on its own to detect trace amounts of mycotoxins left after irradiation, nor is mass spectrometry when used in isolation.听Adding听molecular and culture-based methods听allows testers听to听track听smaller fragments that ELISA听or mass spectrometry听alone might miss.听

鈥淎听single spore can cause disease, so we had to go beyond听the听ELISA limit to see.听To the general听population, this听may not have much significance,听but听immunocompromised people听will be at much higher risk,鈥澨齭aid Saji George, study co-author and Professor听at the Department of Food Science and听Agricultural听Chemistry.听

Industry collaboration and next steps听

The researchers听stressed听that听once听contamination occurs, it is extremely difficult to remove, so prevention is key. They are working with industry partners听on听such听solutions听as beneficial bacteria that听prevent听harmful fungi听from听establishing听on听the crop.听

鈥淐annabis听buds听have听sticky resins, so听they are听really susceptible听to contamination. These fungi are everywhere, so we need to be more careful at every stage, from growing听and听harvesting to听processing听and听storage,鈥� said Mamta Rani, study co-author and Research Associate at听the听听(SAFE-Nano lab)听at 海角社区.听听

鈥淚t is possible to produce clean cannabis. Some companies we work with have achieved this through strict hygiene practices and controlled environments,鈥澨齭he said.听听

Added George:听鈥淲e are not trying to tarnish the industry, but to help make it more sustainable and provide guidelines for safer products.听We need听stricter safety standards,听especially for medicinal cannabis.鈥澨�

About this study

鈥�,鈥� by听Mamta Rani,听Mohammad Jamil Kaddoura,听Jamil听Samsatly,听Guy Chamberland,听Suha Jabaj and听Saji George, was published in听Toxins.听

The听research was funded by Tetra Biopharma Inc. (G253375).听