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Most Samples Of Spanish Cannabis Contain Traces Of Human Poop


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Pot smokers in Spain might find that their cannabis is laced with some particularly unpleasant contaminants – specifically human feces.

According to a study recently published in the journal Foreign Science International, the vast majority of hashish samples (88.3 percent) collected in and around the Spanish capital, Madrid, were not suitable for consumption. What's more, a large chunk of those contained traces of E. coli and the remnants of human poop. Some are at levels 500 times higher than those allowed by US law for cannabis or European law for fruit.


A total of 90 samples were gathered over a period of 12 months. Sixty of those samples were tested for foreign elements and adulterants, and microbiological contamination, plus odor. The remaining 30 were tested for E. coli, a bacteria that lives in the human gut but carries strains that can cause nasty bouts of food poisoning. 

Overall, 93 percent of acorn-shaped samples and 29.4 percent of ingot-shaped samples were found to contain E. coli. Charmingly, 40 percent of those samples carried a fecal odor, while all samples that carried a fecal odor contained E. coli. The moral of the story being that if your cannabis smells like shit, it probably is. 

This, the researchers say, most likely comes down to the process of distribution. While the cultivation of cannabis plants for your own consumption is legal in Spain, the cultivation, trafficking, and public consumption of hashish is not. These samples, bought on the street, most likely arrived in Madrid from abroad, smuggled in via peoples' bellies.

"Once they arrive in Spain, they take laxatives to expel the acorns. And that's what goes on sale," Manuel Pérez Moreno, a pharmacist at the Faculty of Veterinary Medicine and co-author of the study, told El Pais


On top of the high fecal count, the researchers found that many of the hashish samples had been contaminated with foreign substances and adulterants, including hairs, sand, plastic, and textile fiber. Of the 25 percent of samples that had been adulterated, 66.7 percent had an ingot shape.

Meanwhile, 10 percent were found to contain spores of Aspergillus, 66.7 percent of which were acorn-shaped.

The good news is that the fungus is normally harmless. The bad news is that it can cause serious infections in people with asthma, a weakened immune system, or underlying lung disease. A fact that could be particularly problematic for the increasing number of people who are using cannabis for medical purposes – say, for example, to relieve chronic pain or reduce the side effects of chemotherapy. 

"These patients have weakened immune systems, so an infection caused by the consumption of contaminated or adulterated cannabis resin could be fatal," the authors warn.


The 90 samples included in the study are just a small fraction of the hashish distributed in the area, so it is hard to say with any certainty that the numbers are truly representative of the cannabis sold in Spain (or even Madrid) as a whole. However, the study authors do point to other studies that show similarly high levels of contaminants.

This includes some from the Netherlands, where cannabis is decriminalized, suggesting roughly half of samples contain dangerously high levels of E. coli and 70 percent show enough fungal growth to make them unfit for human consumption.


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