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Mold In my Clay


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For about a month Ive been having some type of allergic reaction on my skin, itchy bumps on hands and my body is itchy all over! I couldn't seem to figure it out but now I think its mold in my clay. This started happening when I started using porcelain (I read porcelain can grow certain types of mold), but there is also mold from my other stoneware clay bodies. 

After I throw I put all my slip, extra clay water, and clay bits into a bucket. This bucket usually sits for a while, sometimes weeks or months until It dries enough to put it on my plaster bat to reclaim it, in the summer this is much quicker but now its winter and my basement is cold and it dries much slower. When I'm reclaiming my clay it usually stinks a bit and sometimes there is dark or black soot or probably mold in the bottom of my reclaim bucket. I usually just throw it all on the plaster bat and wedge it up after its drier. The clay is most usually a darker color than it was when it was fresh because of this mold. This usually wouldn't bother me and has no affect on the usability of the clay, but after more than a month of moderate allergic skin reactions Im scared to touch and reclaim my clay knowing it has mold in it. Im not sure what to do, I have buckets of clay slop that need to be reclaimed and it would be such a waste if I threw it all out. Ive heard of using bleach or vinegar to kill the mold so does anyone know how much vinegar or bleach to pour into my slop buckets to kill the mold? My bagged fresh clay from the store is fine and mold free, just when I leave it to be reclaimed is when the mold grows. Please let me know if anyone has some remedies or been through something like this! 

Also, I have my slop buckets sitting out in my basement studio, could mold be in the air or getting into my lungs? I Wouldn't want something severe to happen. Probably not too many doctors on here but if anyone knows anything about the mold that grows on clay let me know :) thank YOU!

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The stink and black growth you're describing is normal, and unless you have specific allergies to mold, you should be ok. As far as your lungs are concerned, silica dust from not mopping is worse for an adult without allergies. The stuff that grows in the bottom of the bucket is anaerobic, hence the funk. Mold growth is normal and encouraged to a point, because it it changes the PH in your clay, which leads to a certain level of increased plasticity. It can also be a mild skin irritant, especially if people have added things like vinegar or yogurt to encourage said bacterial growth. Vinegar doesn't stop the bacteria, it encourages it. If you're getting a red bumpy rash on your forearms, the best remedy is to not wipe your hands on whatever you have covering your legs, and then subsequently brace in the same spot so that the clay transfers to your arms and chafes. Keep a separate towel or rag handy to clean your hands off with.  Submerging your arms in your reclaim bucket for long periods to mix it should be avoided. It's also important to wash thoroughly with lots of soap any spot that was covered in clay once you're done your session. Twice.  Rinse well, pat dry and then put on a good, heavy moisturizing cream. Things like Bag Balm, any kind of formulation geared to mechanics or gardeners, Burts Bees, that kind of thing, are popular choices. Barrier creams, such as Gloves in a Bottle may also help.

If it's something other than contact dermatitis, you should check with your doctor about remedies.

To fix whatever you've got going on in your bucket, prevention is usually better than trying to fix it afterwards. If you're leaving your reclaim in buckets that long, it's going to have more opportunity to grow stuff. It's also contributing to your long drying time. If you can, mix your reclaim into a smooth slurry with a strong drill like the kind tile setters use for grout, and paint mixing bit. Pour it out to dry it out on your plaster bat. This process will give things less time to grow. I'd avoid adding vinegar (see above) or bleach, because bleach will irritate your skin more. If the reclaim gets really gross, like growing excessive green fur gross, you could add a shot of peroxide as an alternative. It will only back off the growth, it won't eliminate it entirely, so if you leave it for another long period, it'll come back. 


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depending on how much clay you use at each session, workday, you might be able to dry out the bits not used and reclaim that way.   if the pieces are small and thin, drying them out on a board or drywall will allow you to store a lot of clay in a smaller bucket.   when you are ready to re-use it, pour fresh water into the bucket until just covering the dry bits.   slake them overnight and wedge the next day.   no wet buckets sitting around.

reclaim the slip that has formed when you throw by pouring off the clear water a day after throwing.  sieve the remainder and keep it for decorating pieces made of the same clay.   using that slip during wedging the slaked clay will return some of the fine bits that help keep the clay plastic.   

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They put out a fear of mold because it's EVERYWHERE!  What easier say to sell products than to make people scared of what is everywhere?

It is much more likely you are allergic to any number of metals present in clay or glazes.

The timing of Porcelain sounds coincidental.

Any new glazes for the Porcelain?




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As everyone says above, plus:

Wear gloves when re-claiming.  I have very dry skin and wear gloves for almost all my work with clay (I don't throw), and ALL my work with glaze.

Try not using any reclaim for a month and see if it improves.  If it does, you know to either dump all reclaim or as OldLady says, dry it out immediately and don't keep slurry around.

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