U.S. Code of Federal Regulations
Regulations most recently checked for updates: Aug 27, 2025
On the basis of frequency of occurrence and severity of reaction information, the Commission finds that the following substances have a significant potential for causing hypersensitivity and therefore meet the definition for “strong sensitizer” in section 2(k) of the act (repeated in § 1500.3(b)(9)):
(a) Paraphenylenediamine and products containing it.
(b) Powdered orris root and products containing it.
(c) Epoxy resins systems containing in any concentration ethylenediamine, diethylenetriamine, and diglycidyl ethers of molecular weight of less than 200.
(d) Formaldehyde and products containing 1 percent or more of formaldehyde.
(e) Oil of bergamot and products containing 2 percent or more of oil of bergamot.