Out of all the things you’d expect to find in cannabis, fecal matter is most definitely not on the list.

A 10-gram “brick” of hashish. Image via Wikipedia.

Buying drugs… for science

Hashish (commonly known as hash) is a drug made from the resin of the cannabis plant. It’s been consumed for centuries and is still very popular in some parts of the world, while remaining a common niche alternative to “classical” cannabis. Hashish, of course, is illegal in most countries. As a result, there’s also no guarantee that the hashish sold on the streets is clean and fit for consumption.

Researchers from Universidad Complutense in Madrid wanted to see just how contaminated street hashish is, so they did what any responsible scientist would do: they hit the streets to buy hashish.

“The aim of this study is to analyze the adulteration and contamination of cannabis resin obtained on the streets of Madrid, in order to establish whether it is suitable for human consumption. A total of 90 samples obtained through street vending in the Region of Madrid (CAM) were analyzed,” researchers write in the study.

The team split the drug into two groups — “acorns” and “ingots” — based on their shape. They found that ingot-shaped samples were much more likely to be contaminated than acorn-shaped hash, but overall, the results were very dire.

The vast majority of the samples they tested (88.3%) were deemed not suitable for consumption — the main reason being E. coli contamination, an infection which can cause vomiting, fever, and diarrhea. Researchers also found that 10% of the cannabis samples were also contaminated with Aspergillus — a dangerous fungus that can cause serious health problems.

Brown hash

Their analysis also found that 1 in 4 samples were intentionally contaminated, and many samples contained disturbingly high amounts of fecal matter (especially the “acorn” ones) — levels which again, the researchers classed as unsafe for human consumption. All the hash samples containing fecal matter were also contaminated with E. coli, and many of them also had a faint fecal smell.

The reason for this is connected to how the cannabis is brought into the country, researchers say. The cannabis is wrapped up in small plastic pellets and swallowed by smugglers. After they cross the border, the smugglers take a laxative and expel the cannabis and sell it to dealers — a process which leaves behind a brown trail.

While the findings should be disturbing for all hash smokers, researchers are particularly worried about cancer patients who smoke it to alleviate the symptoms. Their immune systems can be weakened by treatment, making them more susceptible to infections such as the ones carried by the hashish.

While the study was carried out in Madrid, there is good reason to believe that similar results would be obtained for the hash in other parts of the world, since the “swallow and release” method is quite common.

The study has been published in Forensic Science International.