I was a clay teacher for over 40 years. What you describe is common problem with rework clay, and even with new clay that has been in moist storage for long periods. In all my classroom years this a problem for only one student who happened to have an allergic reaction to the mold. She was hypersensitive to molds, and could not be in the room. For everybody else it was a bit smelly, but to my knowledge it was never a health risk. I believe you can safely use the clay. Some ventilation is always good. In my opinion, clay and glaze dust can be a greater problem, but there are good ways to control those by using only wet smoothing and wet cleaning methods. Avoid sanding, counter brushes, brooms, and vacuum cleaners.
You can search Hazards in Ceramics and/or Cleaning and working with less clay dust for more information.
On Apr 4, 2011, at 8:19 AM, Paternoster, Dana wrote:
I have a clay question. I have clay in my classroom that was bricks when I got here six years ago, and that I have recently been reclaiming. I seems to be molding very quickly. I may be mixing different kinds of clay together too.
It smells really bad, and I have been telling the kids that the clay is old, and could be moldy and that is why it stinks. They are just grateful to get to use it, and have not been complaining, but I am also not requiring them to use it, either.
Is there a way to kill the mold? It does not seem to be just on the surface, but going through the clay. That is unless I have a grey clay mixed with the other, but the grey parts of the clay stinks worse than the rest.
Am I in big danger of making us all sick?
I don't have money to buy new clay.
Thanks for your help.
Visual Art Department
Seaford Senior High School
(302) 629-4587 ex. 248
Department Web Site