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January 2006 - Herbal cannabis in the UK is being contaminated with microscopic glass beads - if you've arrived directly at this page, see the feature on contamination here

Question marks surrounding processed weed
By Jan Sennema

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Processed weed? At first hearing it's a laughable concept, because how could you possibly dilute a natural product such as weed in order to make its weight higher? After all, you'd know immediately if someone shoved a bunch of cabbage leaves among your buds, wouldn't you? But the ingenuity of the profit-seekers knows no bounds; for some time now rumours have been doing the rounds in cannabisland about a processed weed that even the highly knowledgeable cannot tell with the naked eye that it has been jiggered around with. There is - understandably - some concern about this, because if the stories are true, then people are being swindled, and even more seriously, smokers are facing unquantifiable health risks. Through our contacts, Soft Secrets got hold of two samples of weed, one of which according to the person who supplied us had been doctored, and the other had not. To the naked eye the two samples looked identical, but with a magnifying glass there were certain differences that could be made out.

As long as there has been trade in commodities, products have been cut and adulterated. The scarcer the product, the sooner somewhere in the distribution chain someone is tempted to bump up their profit margin by diluting said product with a neutral substance. This form of consumer deceit is really not the exclusive domain of 'criminals', because even in the supermarket you can find countless examples of (sometimes legal) fraud, for example with water and cheap 'chicken pieces' - protein-sprayed chicken meat that in many supermarkets are sold with complete legality but misleadingly as 'chicken product'. Mmm, tasty.


If honesty in the legal world can no longer be relied on, then in the underworld of course there is absolutely nothing to hold them back. Naturally, one illegal substance lends itself better to being cut than another. What also counts is that selling adulterated dope in certain circles is really not a good idea. Hard drugs in particular are well known to be cut on a large scale with strange substances. With caffeine, manitol, inositol, fructose, dextrose, vitamin E and these days even atropine-cut coke and speed are more the rule than the exception. Hashish too was and still is regularly adulterated, both in the land of production as well as by dealers in the country it is distributed. The list of substances that have been used for this is long: as well as the addition of low-value leaf material from the hemp plant itself, they include animal fats, soap, henna, shoe polish, paraffin, sand and camel shit. Although it is perfectly possible that the latter is no more than an anecdote from the rich dope-folklore. Opium has also over the years been one of the usual suspects, especially regarding hash coming out of India and Nepal - even though opium here is more expensive than hash and so it would actually be a bonus for the consumer, you might say. Nederhash has also been found cut with foreign substances. Herman, the grow shop owner who tipped us off about the adulterated weed says: "A customer came in one time with marvellous, beautiful Nederpolm. At first we thought 'oh, what a wonderful colour', until we stuck it under a microscope. Then it was clear that were ground fibres from an ordinary pair of stone-washed khaki jeans mixed throughout it."

Blind as bats

Hashish is a perfect candidate for having weird substances mixed with it thanks to its easily-kneaded texture. With weed, this is a bit harder. In spite of this, there have always been smart Alecs who have dreamed up ways of boosting the weight (and therefore profit margin) of weed. For years now within the cannabis trade, it has been known that weed is not always the purely natural product that we think it is. And this is not a reference to the pesticide residues or other chemical crap that is regularly used in the nation's commercial green fields. "Dude, that is as old as the road to Rome", says coffee shop owner Erwin from the Randstad laconically when I ask him if he's ever had any contact with processed weed. "I have often been offered weed with starch on it, but you'd have to be totally blind not to see that immediately." If that is true, any savvy businessman would pick out such an adulteration immediately. And it looks unlikely that a lot of weed treated in this way has been turning up in coffee shops, since according to those in the know it was mainly weed destined for export.


And that is still the order of the day, or so it seemed according to an article in the September issue of the German hemp newspaper Hanfjournal, in which readers were warned about a certain shipment of weed that came out of the Netherlands. In the article it was stated that: "At the moment in Holland, it is established practice for huge quantities of worthless weed to be sold abroad for ready cash. It concerns low-value and already pollinated weed that has then been processed in some way. The odour is very weak and 'green'. When it is smoked at first you do not notice anything unusual, and the ash too looks normal, but the stuff has virtually no effect. If you inspect it more closely you see within a few minutes a crazy mass of powder that looks absolutely nothing like cannabis glands. We suspect that it may be talcum powder. Thanks to this, at first sight it looks like a super weed; logical then that it is a bit more expensive. A pure swindle. In the first place this weed is pollinated and so has already brought in money. Secondly you gain some weight, and thirdly in this way you can also flog the most worthless weed."


Over the years fraudsters have tried in many ways to ratchet up even further the already not-to-be-sniffed-at profits made on Dutch weed. A random selection of some of the substances that have been used to add more weight to the scales: iron filings (extra weight), starch, flour and baking powder, especially popular since the rise of the 'white' varieties (add weight and a tasty-looking white frosting), cola, sugar water and even cement. This last substance was spread over the plants with a ventilator in order to pop a few more grams on them before harvest. A real cannabis veteran told me how way back when, the inside of the stalk of the cannabis plant, which consists of white pulp, was dried out and in ground form strewn over the buds. In that case at least the additive was still a cannabis product. The nicest and cleanest way of bumping up profit margins is without doubt the trick that was apparently used regularly a few years back. The supplier hid a couple of the old five guilder coins in the middle of a kilo bag, and because these coins weighed around 20 grams apiece, this was weight he did not have to make up with weed. What was so psychologically compelling about the trick was that the swindled finder naturally for no moment felt like he'd been had, but on the contrary that he was a lucky so-and-so. So hey, if you can swindle someone and make them feel like that, you're almost an artist. And for the consumer there was of course no specks of crap in the air.


This sort of fraud, with a dose of good will, can still almost be described as a kind of innocent flim-flam that fits in with age-old Dutch trading traditions. But with the adulterated weed that is now being offered at various places in the Netherlands, there is possibly something more serious going on. Among prominent cannabis pioneers, Herman is not exactly unknown. He's been running a wholesaling business as a spin off from his grow shop for a good 15 years. One of his many contacts knows people who are active in processing weed, and he managed to put two samples Herman's way. Of these one was, according to the contact, and the other was not treated with an unknown substance. Herman: "In all the time that I have been involved in this business I have often come across weed that had been meddled with," says Herman, "but if I tapped this bud then white powder fell out from it. What's worrying about this scam is that it is not possible with the naked eye to spot it. Only with a strong magnifying glass are the small differences visible; the stuff used can then be seen again as little flakes. I think. According to someone I know, it might be wallpaper paste, but it could just as well be some kind of polymer or other that has been tinkered with."

In itself, wallpaper paste is not an illogical conclusion, because the stuff, that primarily consists of cellulose (which is present in wood), binds with moisture and dries out transparent. Sadly, it is hard to pin down with analysis because the cannabis plant also contains cellulose.


According to Herman the appearance of this new generation of adulterated weed is a direct consequence of the scarcity on the market that has existed ever since the increasingly hard crackdown against growers in the 'Golden Triangle' of Limburg (southern province of NL - ed.). "We are well used to a certain level, but in recent times it has become considerably more than a trickle. We even hear stories of buyers walking around with magnets in order to check that there are no iron filings in the weed. If you sprinkle these over wet weed then you will not be able to notice them once it has dried out." The alarm bell started ringing when suddenly all over the Netherlands wet weed was being bought up on a large scale. "It began in the South and is spreading out like an oil spill over the rest of the whole Netherlands," says Herman. "For ten kilos of wet weed they are paying the price that you would normally pay for two kilos of dried, or 20% of the wet weight. Then the weed is already dried and had its leaves removed. I reckon they are making the weed even wetter and then rolling some kind of powder or other through it. Then it is dried out in a day or two (normally commercial weed is dried for about a week - ed.), thanks to which the little leaves contract very quickly. According to the guy who gave me the samples, the weed weighs about 10-25% more after it has been processed."

Enormous amounts

With wholesale prices hovering around the three euro per gram mark, it is clear that we are talking about enormous amounts. The appearance and smell of the processed product are no different to that of unprocessed weed, thanks to which it is extremely hard for buyers to tell the difference between a kosher and a potentially dangerous product.

"If I can not or barely see that it has been processed, then neither can 99% of the shop owners tell the difference," says Herman, "so I know for sure that it is being sold in the Netherlands on a huge scale in shops. Let's assume that 70% of weed at the moment is being sold wet," he continues. "Of that, maybe 80% is being sent abroad, but the rest is landing up in coffee shops." Herman is seriously worried about the phenomenon, for a start because the health of innocent dope smokers is being toyed with, but above all because the government is always ready to pounce on any argument for even more repression. If there really is something going on, then 'the demon weed has done it again' and those who are against cannabis will have yet another argument to justify an even tougher approach, he argues.


Comparable reports coming out of the provinces of Brabant, Utrecht, Limburg, Gelderland and Zeeland largely reinforce the thrust of Herman's story, and there are now newer (and grimmer) variants coming to light, for example in the province of Zeeland. In a South-Holland grow shop I heard the story of a shop owner who had been told of a 'very reliable acquaintance'. He had got a couple of kilos of 'lovely white weed' to split up. When he stuck one of his arms in the bag, it came back out with burn blisters on it. According to this informant it was caused by a pigment for powder coating, a heavy chemical substance.

But whoever I spoke to about processed weed, almost all of them would only do so on the condition that they could be quoted anonymously, and that speaks volumes in itself. Arne, who runs a grow shop in Limburg, was a short while ago thanks to a customer also confronted with adulterated weed. Having listened to his story it looks likely that there is also another processing method being used. "A friend came over with two small samples and asked me which one I found the best looking. Apparently, I picked out the one that had been processed! You just cannot see anything wrong, and the smell too is exactly the same as the non-processed one. At first I completely could not believe that there was anything dodgy, but the person who brought it to me was absolutely trustworthy. Only once you looked at it under a microscope could you see that there were weird rectangular blocks on it." Arne too has an extensive knowledge of weed, but unlike Herman, who in principle will not smoke anything he does not trust, Arne wanted to know the truth for himself and rolled a joint with the suspected sample. "One drag was already enough. It tasted chemical, sharp. I had heard that the stuff with which the weed had been adulterated was a chemical product from DSM (large Dutch chemical company - ed.) that is sold in kilo bags. The stuff was sprinkled all over wet weed which was then freeze dried."

White coats

But enough of all these vague suspicions. We want some hard facts. Analyses, graphics, men in white coats. So it's off to CannaResearch. When we turned up at CannaResearch with our samples, the world famous lab was more than happy to research what substance had been used. Not so strange, because the investigation actually fits seamlessly with the research into pesticide residues in weed that CannaResearch has long been busy with. But I was warned directly that it would not be an easy task to sort without any clues through the tens of thousands of chemical agents that exist at random to discover the identity of a single unknown substance. That would take years. But that something was done to the suspicious sample, was fairly quickly found out by the smart boffins at CannaResearch. More reliable sources had also reported examples of processed weed to CannaResearch, thanks to which something that had once seemed to be just the latest urban myth was becoming more and more likely to have some truth to it.

"There is something up"

"The research into the sample is far from over," said Ron from CannaResearch. "But from what we have learned so far, it seems that we have established that there is something up. Because it is impractical to go looking for particular contaminants out of the blue, we have developed a test with which in any case you can exclude the presence of certain substances, in this instance primarily heavy metals. From this test it was established that there was no indication of metals in these samples, but with this we have only ruled out 1% of all chemical agents, and so this result in no way says that there is no risk to the consumer. We are going to conduct some other tests to see if the THC concentration varies significantly between the two samples, so that we can determine what percentage of the weight consists of additives. What we have also determined is that the product was dried out very quickly. The THC levels are barely influenced by this, but certain flavourings and psychoactive substances, such as terpenes, were broken down, thanks to which the taste and smell were clearly reduced. A real professional smoker will be prompted to ask "what the fuh-?", but a young German kid will probably not notice anything amiss, and just think "whoah - I've got nice and stoned from it." For some time now, CannaResearch has had the facilities to do a chemical analysis of possible pesticides in cannabis products. A ground-breaking service with which coffee shops can cultivate their sense of self-regulation and responsibility. Without a doubt coffee shops will soon be banging on the door of CannaResearch hoping for a test for as yet unknown weed adulterants.


In anticipation of the results from the CannaResearch investigation, the question remains whether the processed weed represents a hazard to the consumer. And although there are enough suspicions, and in any case two informants testifying to the fact that processed weed is making its way in to certain shops, it is still absolutely unclear on how big a scale this is happening and whether the processed weed is remaining in circulation after being discovered. A couple of thousand euros-worth of dope is a lot to flush down the loo purely because there are some vague reports of weed being messed about with, and this is not the reaction we can expect from everyone. And to add to all that vagueness there also comes the possibility that we are not talking about one but perhaps many methods of cutting weed.

Even so, most coffee shop owners that I have spoken to believe that the phenomenon of processed weed will work itself out, even if only because it is pretty noticeable when the much-used kilo bags suddenly start having the same weight but with smaller volumes of weed in them. According to others, this is a rubbish argument, since weed is far from always delivered in such a package.


In spite of the invisibility of the threat from processed weed, coffee shop bosses are not forced to just sit around and take it. One rule of thumb to help prevent buying suspect weed is to insist that the weed is delivered in the well-known kilo bags. Another is to build up and maintain their own network of growers and thereby build up a relationship of trust, which can save a lot of uncertainty, just as can maintaining a critical attitude towards new suppliers. And finally there is the tip to invest in a microscope, which under the circumstances is no longer an unnecessary luxury.

Kite mark

'Whistle blower' Herman thinks that it is high time that coffee shops take responsibility themselves and take some structural steps - which in the same effort another hot potato, pesticides, would be tackled. "I think that coffee shop owners have to make sure that the weed that is handed over the counter has had some sort of 'kite mark' establishing that it has been tested for poisonous substances. Think of the way that in Germany wine is checked. Every wine grower has to have a sample of each wine he produces tested at a laboratory. It costs them a couple of euros, and they get back a test report. By using spot checks it can be checked whether the wine does indeed come from that party. It is not hard to imagine that an institution such as the Trimbos (Dutch drugs research unit - ed.) develops such a test. But that something has to happen is clear, because if we let this slumber then sooner rather than later we're going to once again see total hysteria in the government."

With thanks to CannaResearch and Hanfjournal

Names of people mentioned or quoted in this article have been changed to protect their privacy.


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