What do you mean by tox number? When you say urethane do you
mean Ethyl carbamate with a CASRN - 51-79-6? If your question is
what is the toxicity of ethyl carbamate in humans, I offer the
following information: The United States Environmental Protection
Agency (USEPA) has determined that there is inadequate data to
derive a number to quantify non-carcinogenic health effects by the
inhalation route of exposure. The USPEA has not evaluated the
carcinogenicity of ethyl carbamate. The International Agency for
Research on Cancer has determined that ethyl carbamate is probably
carcingenic to humans. If, on the other hand, your question is
regarding polyurethane coatings typically used to seal wood floors,
among other uses, then the question is what is the toxicity of many
other chemicals (other than ethyl carbamate), some known, some
unknown, some depending on the manufacturer and formulation.
