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UK street cannabis has been found to contain dangerous levels of mould, yeast, lead, E. coli and salmonella.
A study conducted by Manchester Metropolitan University in partnership with Curaleaf Clinic analysed 60 samples confiscated by police in Greater Manchester and Northumbria.
Health experts have issued warnings that these contaminants could cause respiratory problems, neurological damage, and gastrointestinal infections in users.
The tests revealed that 90% of the samples were contaminated with either mould or yeast, 8% with lead, and 2% with salmonella and E. coli. Further independent testing also found highly unsafe synthetic cannabinoids including Spice and K2 in 27% of the samples.
These findings were disclosed following a survey of 500 drug users commissioned by medical cannabis clinic, Curaleaf Clinic.
The study found that nearly two-thirds of illegal cannabis is purchased by individuals seeking to manage medical conditions such as anxiety (49%), depression (49%) and chronic pain (28%).
In contrast, a separate survey of 2,000 adults discovered that only 46% are aware that medical cannabis is legal and can be obtained through specialist prescription.
Dr Simon Erridge, research director at the clinic, commented: “It is crucial for consumers to be aware of the hidden dangers in illegal cannabis, especially as so many people are buying it to manage health issues which could be exacerbated by these hazardous substances.
“The law changed six years ago so there is a legal, regulated and quality-tested alternative for those suffering with diagnosed chronic illnesses which haven’t responded to conventional therapies. Many people are putting themselves at risk, when they don’t need to.”
Over one in 10 have resorted to the dark web, online retailers, and even QR code stickers left by dealers to acquire the substance. Despite the dangers 18% of those who buy illegal cannabis are oblivious that the products they buy may be laced with hazardous contaminants, as an alarming 66% can’t identify mould-contaminated cannabis.
To highlight the perils of illicitly sourced cannabis, Curaleaf has initiated a public health campaign, What Are You Smoking?, targeting those most vulnerable. Billboards displaying the findings of the study have been erected in known drug dealing areas based on data gathered through a Freedom of Information (FOI) request.
So far, an ‘ad van’ showcasing the billboards has visited locations in Tower Hamlets and Lambeth in London and is set to travel to Manchester Piccadilly and Merseyside.
Echoing strategies employed by street dealers, biodegradable QR code stickers directing individuals to crucial information on the risks of unregulated cannabis are also being positioned in these hotspots.
Dr Oliver Sutcliffe, senior lecturer at Manchester Metropolitan University, commented: “We hope to provide valuable insights that will help consumers make safer choices.
“Our findings serve as a stark reminder of the importance of vigilance and education in protecting public health.”