About GPO   |   Newsroom/Media   |   Congressional Relations   |   Inspector General   |   Careers   |   Contact   |   askGPO   |   Help  
 
Home   |   Customers   |   Vendors   |   Libraries  

The Electronic Code of Federal Regulations (e-CFR) is a regularly updated, unofficial editorial compilation of CFR material and Federal Register amendments produced by the National Archives and Records Administration's Office of the Federal Register (OFR) and the Government Printing Office.

Parallel Table of Authorities and Rules for the Code of Federal Regulations and the United States Code
Text | PDF

Find, review, and submit comments on Federal rules that are open for comment and published in the Federal Register using Regulations.gov.

Purchase individual CFR titles from the U.S. Government Online Bookstore.

Find issues of the CFR (including issues prior to 1996) at a local Federal depository library.

[2]
 
 

Electronic Code of Federal Regulations

e-CFR Data is current as of July 22, 2014

Title 16: Commercial Practices
PART 1500—HAZARDOUS SUBSTANCES AND ARTICLES; ADMINISTRATION AND ENFORCEMENT REGULATIONS


§1500.41   Method of testing primary irritant substances.

Guidelines for testing the dermal irritation and corrosivity properties of substances, including testing that does not require animals, are presented in the CPSC's animal testing policy set forth in 16 CFR 1500.232. A weight-of-evidence analysis or a validated in vitro test method is recommended to evaluate existing information before in vivo tests are considered. This analysis should include all of the following that are available: human and animal data, structure activity relationships, physicochemical properties, and dermal toxicity. If in vivo testing is conducted, a sequential testing strategy is recommended to reduce the number of test animals. The method of testing the dermal corrosivity and primary irritation of substances referred to in §1500.3(c)(3) and (4), respectively, is a patch-test technique on the abraded and intact skin of the albino rabbit, clipped free of hair. Primary irritation to the skin is measured by a patch-test technique on the abraded and intact skin of the albino rabbit, clipped free of hair. A minimum of six subjects are used in abraded and intact skin tests. Introduce under a square patch, such as surgical gauze measuring 1 inch by 1 inch and two single layers thick, 0.5 milliliter (in the case of liquids) or 0.5 gram (in the case of solids and semisolids) of the test substance. Dissolve solids in an appropriate solvent and apply the solution as for liquids. The animals are immobilized with patches secured in place by adhesive tape. The entire trunk of the animal is then wrapped with an impervious material, such as rubberized cloth, for the 24-hour period of exposure. This material aids in maintaining the test patches in position and retards the evaporation of volatile substances. After 24 hours of exposure, the patches are removed and the resulting reactions are evaluated on the basis of the designated values in the following table:

Skin reactionValue1
Erythema and eschar formation:
No erythema0
Very slight erythema (barely perceptible)1
Well-defined erythema2
Moderate to severe erythema3
Severe erythema (beet redness) to slight eschar formations (injuries in depth)4
Edema formation:
No edema0
Very slight edema (barely perceptible)1
Slight edema (edges of area well defined by definite raising)2
Moderate edema (raised approximately 1 millimeter)3
Severe edema (raised more than 1 millimeter and extending beyond the area of exposure)4

1The “value” recorded for each reading is the average value of the six or more animals subject to the test.

Readings are again made at the end of a total of 72 hours (48 hours after the first reading). An equal number of exposures are made on areas of skin that have been previously abraded. The abrasions are minor incisions through the stratum corneum, but not sufficiently deep to disturb the derma or to produce bleeding. Evaluate the reactions of the abraded skin at 24 hours and 72 hours, as described in this paragraph. Add the values for erythema and eschar formation at 24 hours and at 72 hours for intact skin to the values on abraded skin at 24 hours and at 72 hours (four values). Similarly, add the values for edema formation at 24 hours and at 72 hours for intact and abraded skin (four values). The total of the eight values is divided by four to give the primary irritation score; for example:

Skin reactionExposure time (hours)Evaluation value
Erythema and eschar formation:
Intact skin242
   Do721
Abraded skin243
   Do722
   Subtotal8
Edema formation:
Intact skin240
   Do721
Abraded skin241
   Do722
   Subtotal4
   Total12

Thus, the primary irritation score is 12÷4=3.

[38 FR 27012, Sept. 27, 1973, as amended at 77 FR 73294, Dec. 10, 2012]



For questions or comments regarding e-CFR editorial content, features, or design, email ecfr@nara.gov.
For questions concerning e-CFR programming and delivery issues, email webteam@gpo.gov.