Marijuana and Mold

Discussion in 'Medicinal Marijuana' started by ikari, Apr 22, 2003.

  1. ikari

    ikari Seasoned Activist

    Everything about MOLD and marijuana

    Hey all,

    I've recently become interested in molds and fungus that apply to the rotting and contamination of marijuana, their related health problems, prevention methods, and so forth.
    I researched as much as I could on the internet about it, and am writing this post because I basically feel that all the threads addressing this issue are heresay and myths. Please note although sometimes I say something along the lines of "this mold is not specifically bad, and won't kill you", i'm saying just that. This does not mean that it won't cause sickness, or that it is not better to just throw away moldy weed, I just like to give people options.

    To start off, I must say that mold and fungus is much more prominent and most likely inhaled far more than people would like to admit, as this study suggests "Fungi were identified in 13 of 14 MJ samples" *1. But is this really bad, which molds are deadly and which are not, do I have to throw away my entire stash if it gets infected? Hopefully conclusions to these questions can be drawn from the information here.

    Please note, any *x is the number of the reference used (references are at the bottom), and anything in "quotes" and italics are direct quotes from sites.

    How bad is bad?

    Here we look at how bad an infection can get from mold, and the most probable results are.

    First, the "bad" part in molds are something called mycotoxins, and seem to be (usually) only bad if someone is exposed to them a lot over long periods of time. It seems most molds contain mycotoxins, so there's not much chance in avoiding them. *8.

    Most effects seem to be allergic reactions or asthma, which usually occur "in sensitive individuals. About 15 million Americans are allergic to mold. The most common reactions are flu-like symptoms and asthma. Those with chronic lung or immune problems, are at risk for more serious reactions like fever, lung infections and a pneumonia-like illness." *8. Most actual sicknesses (like the one from aspergillus), bronchitus, mold "growing" in your lungs, is not a problem for healthy individuals and is not a prominent factor in the most common molds.

    Surprisingly most research indicates that if a strain is particularly bad, it is MUCH worse when digested than when inhaled. Thus, with certain strains it's actually better to smoke the weed than to cook it, as some (notice, it's not all) strains will not die when exposed to extremely high temperatures. Anaerobic Bacteria for example is one of these, while not very harmful if inhaled, it is FAR more devestating when ingested.


    Here we answer, what are the most common molds and how bad are they?

    The only "deadly" mold seems to be one named Stachybotrys, and it is rather rare. So it's not a general concern (as in, I wouldn't worry if you have this one, you most likely don't). As well it seems more deadly (or perhaps higher infection rate) to infants and elder people, or people with generally bad immune systems.

    The most common mold is Aspergillus, and it occurs literally everywhere, from the soil to the trees.. you have definitely inhaled it before if you've ever been outside, and it is not a problem for people with regular immune systems. The problem with this mold arises with people with extremely low immune systems (AIDS, marrow transplants, etc..), where it may cause problems. To further emphasize this point, "Aspergillus is a group of moulds which is found everywhere world-wide, especially in the autumn and winter in the Northern hemisphere. Only a few of these moulds can cause illness in humans and animals. Most people are naturally immune and do not develop disease caused by Aspergillus. However, when disease does occur, it takes several forms." *6. As well, "The simplest may be contaminating pot with fungi like Aspergillosis, which is still toxic when smoked. Healthy people can inhale the spores and not get sick, but medical marijuana users can contract skin disorders, pneumonia and other pulmonary infections, some of them fatal." *4. Basically, I'd say that this mold, although bad, is not really a concern. Most healthy people should have no problem with it.

    Next is Anaerobic Bacteria, which only grows in dark and air tight (ie. sealed jar) situations.. Anaerobic specifically means that it does not require oxygen to grow. This one is easy to identify (brown & slimey, plus you had your stash air tight), and is rather bad. That is to say, it's easy to avoid, and thus you should never run into it, but if you do it's best to just throw it out. The most common of these is a mold known as Clostridium botulinum, and everything you could want to know about it is here:

    Penicillium is another common one. From what I've read, it seems that it is not much of a concern. It's usually rather benign, and is most common from refridgerating (seems to prefer cold), but i'll get into that later. Your only real worry here is from contamination from putting something with the weed that can get Penicillium (ie. for re-hydration purposes), as we can see here: "Adding peels to pot imparts a "pleasant bouquet" (Frank & Rosenthal). In my case, the peel imparted a nidus of infection. _P italicum_, the "blue citrus mold," is notorious for its ability to spread by contact (i.e., "one bad apple spoils the whole bunch")." *2.

    The last one i'll talk about is the one that people often cite reference to when burying their weed to "increase the potency". To describe this more specifically: "More recently, Margolis & Clorfene describe a mold that _increases_ potency in marijuana. Their "black weblike fungus" sounds like an _Aspergillus_ species" *2. This is kind of interesting, in that people will bury their weed in hopes of securing this specific one to increase potency.. but in my opinion it's not worth it, as it seems other strains come up a lot more often and just ruin the entire stash.


    How do you identify if you have a mold or not? I'll try to outline the main ways..

    It seems that "Infested marijuana often darkens in color and becomes crumbly. Anaerobic bacteria turn marijuana into brown slime. Marijuana undergoing rapid decay may feel warm to touch. ... Tufts of fungi are often visible in mold material. In marijuana stored in darkness, strands look white to light grey. Exposed to light, storage molds spawn millions of colored spores in velvet clumps. A slight tap sends these spores into great billowing clouds. Generally, _Rhizopus_ and _Mucor_ produce grey-black spores; _Penicillium_ species are light blue-green; and _Aspergillus_ species are dark green-black." *2, which provides identification for penicillium, aspergillus, rhizopus, mucor, anaerobic, and generally what to look for (colour change, warmth, tufts, spores).

    It also seems that it is possible to check for aflatoxins using a black light *2. It seems "Material contaminated with aflatoxin-producing _A. flavus_ will fluoresce to a green hue under ultraviolet light." *2.

    Prevention & Ways around:

    How do we go about preventing these strains from forming on my marijuana, seeing as any mold is unwanted?

    First, the "fridging" or "freezing" your pot doesn't seem to hold any merit, as penicillium thrives in these situations *2. As well as these, we know of the "contact" spread of penicillium which was referrenced above in the penicillium section from things which can easily get contaminated by it.

    There's no surprise here, the MAJOR factor is (ya, you guessed it) moisture. "Moisture control is the key to mold control. Molds need both food and water to survive; since molds can digest most things, water is the factor that limits mold growth." *3.

    So you might be wondering how much moisture is too much, and how dry is too dry?
    Well, "Living cannabis plants are about 80% water. Perfectly dried marijuana contains about 10%-15% water or moisture content (MC). Material below 10% MC becomes too brittle and disintegrates. Fungi cannot grow below 15% MC. Unfortunately, many growers market their crop _above_ 15% MC." *2.

    For people with Aspergillus infected marijuana, it is recommended that one bakes it for 15 minutes at 300 degrees, as this apparantly does the trick in removing it *7.

    There's also been a lot of theories that "using a waterpipe will filter the spores out" or something of that sort. That seems to be untrue however, as "Moody et al. evaluated waterpipes for smoking _Aspergillus_-contaminated marijuana. Unfortunately, they found only a 15% reduction in transmission of fungal spores." *2.


    It seems that there are quite a few risks with moldy weed, mostly respitory/immune problems. However, these are actually rather limited in their infection rates, and the most common are the more annoying (but not really a problem) allergy/asthma problems. As well, the strains most probable to develop on marijuana don't seem to be of particular deadliness, the more rare ones on the other hand do pose some serious risks.

    Prevention of mold seems to be easiest executed by simply reducing the moisture level until the weed is below 15% moisture content.. however, since there's no way to really measure moisture content, i would just go for "pretty dry".
    I realize quite a few people like to purposelly keep their bud a little moist, through re-hydration or whatever method. Although it might smoke better, the chance for contamination is FAR higher than if you dried the bud out quite well. So it's kind of a gamble i guess.

    There doesn't seem to be any way to reduce the amount of spores that you intake (with the exception of cooking Aspergillus, and perhaps a few others), as even water bongs don't help much, thus if you're going to be inhaling a mold you should know WHICH one it is, and any problems that might be associated with it (or don't take the chance and throw it out).

    I realize I used a lot of direct quotes to say what I wanted, to be honost this is because I'm lazy and the sites said what I wanted to pretty well :). As well, some of the writing might be awkard, and I apologize for that. I wrote this while a bit stoned. Hopefully it flows well enough to understand the points I was trying to make. If not please ask and I'll try to clarify.

    I hope this will help people with mold problems make educated decisions on what they have, what they should do, ways to prevent it in the future, etc..

    Feel free to comment and/or add something from a reliable study I have overlooked or left out..

    10 people like this.
  2. EeJay

    EeJay Senior Member

    If CheapTalk had a FAQ forum (one different to FAQs), this should be put in it.
  3. Nappe

    Nappe New Member

    Thanks for taking time to do this
  4. chronictruth

    chronictruth New Member

    last year i ordered some opium lettuce from this glass pipes website...what a joke...

    {Mod Note: yes...that was a mention of an off-topic subject. Why'd Mama leave it in? Educational purposes of course. This is an exceptional to the "no discussion of off-topic substances" rule...but later in the thread I had to do a little chop chop edit. ta Ta...have a cookie ;)}

    it was full of mold!!! and it grows too. for instance one day there might be whatever amount of mold and it almost doubles every much mold that when you would shake it you would see a dust cloud come off...eventually it was all mold

    anyways i told them to give my money back but they never did...

    it was a scam anyways....opium lettuce is nothing like does not have any affects at all..but they claim its like marijuana in high times

    dont waste your money..not only is it a scam but it's very likely to have a ton of dangerous mold...mainly because they don't dry it properly and grow it outside

    stick with the good old sticky icky...

    but who knows the mj i have right now could have mold...only if it isnt visible..but i cant see any mold on it is very dry so i think what i have now is fairly safe...always a risk though when you are buying
  5. CheebaMonkey

    CheebaMonkey Sr. Member

    AIDS and aspergillosis

    AIDS patients who suffer from immunosuppression are at risk of contracting aspergillosis. But it seems that this pulmonary disease has only been found in smokers that suffer from immune-suppression disorders (Denning et al., 1991; Sutton et al., 1986).


    Denning, D. W., et al. (1991). Pulmonary aspergillosis in the acquired immunodeficiency syndrome. New England Journal of Medicine, 324, 654-662.

    Sutton, S., et al. (1986). Possible risk of invasive pulmonary aspergillosis with marijuana use during chemotherapy for small cell lung cancer. Drug Intelligence and Clinical Pharmacology, 20, 289-290.
  6. G33k$m0k3r420

    G33k$m0k3r420 New Member

    I'm just wondering how people claim you can get hurt from mold spores? Think about it, what do we do with weed, we BURN it when we smoke it. Can spores survive that?
  7. ikari

    ikari Seasoned Activist

    Yup, quite a few spores can easily survive that. In fact, Terence McKenna is known about writing how it was possible for certain fungus (mushroom) spores to survive in outer space actually, past many of the common radiations and extreme heat/cold, because the spores are very strong. This might not be entirely true, but they are resiliant.

    I can't find a direct quote at the moment (I ran into one while doing this thread), but I can re-use:
    "Moody et al. evaluated waterpipes for smoking _Aspergillus_-contaminated marijuana. Unfortunately, they found only a 15% reduction in transmission of fungal spores.".

    A waterpipe means that it was a bong, and that they burned the weed and drew it through the water.. And it was only 15% reduction.. so obviously quite a few were still getting through.
  8. Higher Logic

    Higher Logic Web Developar

    I just want to throw some questions out and see what you have to say so we can expand this a bit:

    What about the differences in using a butane lighter, a match, and a torch lighter? Different heats I assume, so which ones would allow which molds to survive, if any, and which ones don't kill molds at all.

    Would a microwave (short nuke, about 5 seconds) "kill" any remaining bacteria and/or mold?

    What is the best way for storing bud? Baggies allow for air, even the "air tight" ones. Some people like to keep their bud fresh if they are only going to have it for a short time (less than 3 days) by putting a damp cloth, or similiar, in with the bud, or by putting it in an air-tight container. Obviously air-tight containers won't stop mold, but what about vacuum sealing and then storing in a freezer/refrigerator?

    Is there a "perfect" temperature/humidity to keep bud at? If so, what is a good number or ratio?
  9. lunaticg

    lunaticg New Member

    I just bought a nice big bag, it was a little damp, and I guess I had the bag rolled up a little too tight..... to make a long story short I checked it today and some of the buds were light grey, telling me that mold had started. I have them in the oven right now at 300° for 15 minutes will they be O.K. after that?
  10. EeJay

    EeJay Senior Member

    Re: Everything about MOLD and marijuana

    Going by this post, it might seem like what you're doing is enough, but then again, do you KNOW you have the Aspergillus strain of mold? I'm not sure if it applies to other strains but it isn't stated, so personally, i'd play it safe and chuck it out. But maybe ikari can give you a better answer.
  11. ikari

    ikari Seasoned Activist

    Re: Re: Everything about MOLD and marijuana

    No you hit the nail on the head. Only applies to Aspergillus, and it's not easy to say if you have that 'for sure'.. so if you're not sure, it's not safe..

    From what I read spores tend to survive even extremely hot temperatures.. a few posts up is my reply to G33k$m0k3r420 on that exact subject..

    Hard to say, depends how hot it gets.. it's temperature based, but keep in mind only Aspergillus dies at 300degF.. so the rest can take pretty hot temperatures.

    As i said in my original post, "Living cannabis plants are about 80% water. Perfectly dried marijuana contains about 10%-15% water or moisture content (MC). Material below 10% MC becomes too brittle and disintegrates. Fungi cannot grow below 15% MC."

    Thus you want to keep it below 10% moisture content.. so non-airtight methods of storage are best.. as well, at high moisture and in non-oxygen (air tight) settings, you run the risk of Anaerobic Bacteria..

    I think most of that was stated in my original post or subsequent replies.. please the previous posts in the thread carefully before asking.. :)
  12. lunaticg

    lunaticg New Member

    Thanks for your reply's guys. WOW I just found this site yesterday and I have learned soo much already.
    Keep up the awesome site guys!!!:)
  13. Qwel

    Qwel New Member

    This is a reply to chronictruth, yeah man I orderd that **** too, what a bunch of BS. Not to mention it smells and tastes like ****. I really have to wonder about there page of references of people who send emails saying how much they like that ****. It has to be the people that work for the site, there is no way any respectable pot smoker would think this compares (does anything for that matter) to the real thing.

    {Mod Note: Message portion about offtopic drug deleted per our "no discussion of off-topic drugs" policy. Thanks for your understanding!}
  14. tokeaway

    tokeaway New Member

    very cool dude thanks for taking the time its very helpful
  15. break it all up

    break it all up New Member

    Props on the report ikari. :thumbsup: Ill prolly print this out, because I always was curious about mold on weed.
  16. cky

    cky New Member

    that was pretty much everything i need to know , in fact everything i need to know
  17. bongcritter

    bongcritter New Member

    Hey, nice article, but I have a question.

    Every stash I get I put a wet q-tip in with it in a medicine bottle. I leave it in for a day, and the q-tip is taken out dry. After the entire process, the bud receives the moisture I think (where else would it go?). Will mold grow because it's moister? Eee help. Thanks!
  18. sleepischeap

    sleepischeap New Member

    how about if i vaporise the weed so the thc comes off and leaves the mold behind. will that work?
  19. firsttimer

    firsttimer Banned

    What category would Powder Mold Be under? What would be the name of the mold? I just have heard stories about this and don't want my crop to be contaminated... Where I got the clones from they said they have had PM problems.. So what type of measures could I do to make sure the spores don't live? They are at the begging of Vegging Period?
  20. Mamabudz

    Mamabudz Guest

    Sleep: sorry but a vaporizer would still allow the mold spores to migrate to your lungs...

    Firsttimer: for info on molds during growth hop on over to the Nursery area of our sister site

Share This Page