– Samples of cannabis collected were tested for bacteria
– Three quarters were contaminated with E.coli which could cause illness
– Most of the samples were too dangerous to be consumed, the scientists said
– It could pose a threat to people who use the drug to alleviate health problems
Cannabis being sold on the streets may be contaminated with faeces, scientists have discovered.
Samples sold in Madrid were tested and found E.coli bacteria in three quarters – the diarrhoea and vomiting bug can be transmitted through human faeces.
Most of the samples were too dangerous to be consumed and pose a ‘public health risk’, the researchers said.
Though the study was only conducted in Spain, one expert told MailOnline the same ‘unusual’ thing could be happening in the UK and other places in Europe.
This is because of the way the drug is sometimes smuggled into countries – by swallowing it and later excreting it with the use of laxatives.
Experts said the findings are worrying considering some people who use cannabis do so to try and alleviate health problems.
The research team, led by José Manuel Moreno Pérez, a pharmacologist from the Universidad Complutense in Madrid, collected 90 samples in Madrid over a year.
The samples were separated into either ‘acorns’ or ‘ingots’, which are the shapes they are bought in.
Each sample was then broken down into smaller pieces and looked at under a microscope, the authors write in the journal Forensic Science International.
They found that 93 per cent of the acorn-shaped samples were contaminated with E.coli, as well as 29.4 per cent of the ingot samples.
Some 10 per cent of the cannabis samples were also contaminated with Aspergillus, a dangerous fungus that can cause serious health problems such as lung infections.
A total of 88.3 per cent of the cannabis samples were not suitable for consumption based on the amount of E.coli contamination allowed by guidelines in the EU and US.
The odour of each sample was also recorded and 40 per cent of acorns had an aroma of faeces, the researchers said. All of these were contaminated with E.coli.
This led the researchers to suggest the way the cannabis is transported into the country – where it is illegal – may be to blame.
Mr Pérez told Spanish newspaper El País the cannabis is wrapped up in small plastic pellets and swallowed before the drug smugglers then ‘take a laxative and expel’ them in a toilet.