Disposal of polyurethane resin

I work with polyurethane resin, and up until now was doing so at
school which took care of the disposal. I was wondering if anyone
knows what the proper disposal procedure is for my home studio; or
if anyone knows of who I should get in touch with to find out (I am
located in Ontario) I don’t want to put anything in the garbage
that could cause negative environmental ramifications.


In my area (SC, US), such items can be disposed of with the regular
trash if they are first left to dry completely. For example, if you
had some leftover paint in a bucket you would set it out to dry and,
once it had, dispose of it in the regular bin. It does make me cringe
to think about it, though.

Courtney Graham Hipp
cgHipp Jewelry Designs

I work with polyurethane resin, and up until now was doing so at
school which took care of the disposal. 


In my prior career, before becoming a wax carver, I had some
dealings with polyurethane in the work place at the factory I worked
at in Toronto.

First of all, don’t know how much polyurethane you are using, but if
this is a 2 component foam or resin, there is a high possibility
that during the curing process it releases trace amounts of
isocyanates, which is a designated substance in Ontario and most
other provinces and states. Check out this link to Ontario’s
Occupational Health & Safety Act dealing with products containing

If you don’t have them, get the MSDS sheets from the manufacturer to
determine if the product you are using contains isocyanates. As for
disposal, my understanding is (and if others can confirm or correct),
once the 2 components have been mixed and cured, it is no more
hazardous than any other plastic resin. The best place to check would
be Ontario’s Ministry of the Environment, but before you call, get
the MSDS sheet so that you can describe the product to them.

Richard Dubiel
Tel 905.566.0950
Fax 905.290.9398

Courtney, you must be careful with disposal of polyurethane, even in
the cured state. Some polyurethane products contain mercury
compounds, which are added for tear strength. No new recipes can use
mercury compounds, but some of the older recipes have been
grandfathered and thus permitted to continue using mercury

Mercury is a cumulative poison. It builds up in your system over
years of exposure. It is not eliminated by your body like most other

Check your local laws. It would also be a good idea to request MSDS
from Castaldo, Romanoff and Smooth-On, if you are using
products from these companies.

Contact Zero-D Products, Inc. for Silicone RTV 800-382-3229


Bill Mull