CPSC – Final rule – Revisions to Supplemental Definition of “Strong Sensitizer”

Posted on: April 16, 2014

By Jennifer Haggerty

The Consumer Product Safety Commission (CPSC), under the Federal Hazardous Substances Act (FHSA), has published a revision to the supplemental definition of “strong sensitizer.” The revision was published to reduce redundancy and subjectivity from the previous definition. It also allows a weight-of-evidence approach to be applied to substance classification. The rule went into effect on March 17 of this year.

Previously, a strong sensitizer has been defined as “a substance which will cause on normal living tissue through an allergic or photodynamic process a hypersensitivity which becomes evident on reapplication of the same substance and which is designated as such by the Commission. Before designating any substance a strong sensitizer, the Commission, upon consideration of the frequency of occurrence and severity of the reaction, shall find that the substance has a significant potential for causing hypersensitivity.”

The definition has been supplemented before, in 1961 and 1986, to try to provide clarification. The definition is now supplemented by the following:

Sensitizer. A sensitizer is substance that is capable of inducing state of immunologically mediate hypersensitivity (including allergic photosensitivity) following a variable period of exposure to that substance. Hypersensitivity to a substance will become evident by an allergic reaction elicited upon reexposure to the same substance.

Significant potential for causing hypersensitivity. (A) Before designating any substance a ‘‘strong sensitizer,’’ the Commission shall find that the substance has significant potential for causing hypersensitivity. Significant potential for causing hypersensitivity is a relative determination that must be made separately for each substance. The determination may be based on documented medical evidence of hypersensitivity reactions upon subsequent exposure to the same substance obtained from epidemiological surveys or case histories; controlled in vivo or in vitro experimental studies; susceptibility profiles (e.g., genetics, age, gender, atopic status) in non-sensitized or allergic subjects; and chemical or functional properties of the substance.

For complete information on the definition and how the CPSC determines whether a substance is a strong sensitizer, please see the FHSA definitions section.

Federal Register excerpt:


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