determine the irritation potential of a test article or series of
test articles after a single 48-hour patch exposure to the skin
of human subjects.
100 or 200 healthy men and women
Start test within 2 days - 1 week after receipt of sample
Report issued within 3 weeks of study completion
oz. per 50 subjects
assessment of skin response by a trained evaluator
0.05 mL or grams of each test article is applied to the test patch
(absorbent discs affixed to occlusive or semi-occlusive adhesive tape).
The patches are applied to the subject's back, the upper arm and/or
the volar surface of the forearm.
Forty-eight hours after application, patches are removed and the test
sites are scored by a trained ETC examiner. The sites are again scored
72 or 96 hours after application.
Skin responses are scored according to the following 6-point scale:
0 = (None) No evidence of any effect.
+ = (Barely perceptible) Minimal, faint, uniform or spotty erythema.
1 = (Mild) Pink, uniform erythema covering most of the contact site.
2 = (Moderate) Pink-red erythema, uniform in the entire contact site.
3 = (Marked) Bright red erythema with/without petechiae or papules.
4 = (Severe) Deep red erythema with/without vesiculation or weeping.
Accompanying edema (swelling) at any test site is recorded with an
"e" and described as mild, moderate or severe. Other possible
dermal sequelae are similarly recorded.
The subjects are asked to report any delayed reactions which might
occur after the last reading. At the Sponsor's option, and for an
additional fee, readings may be taken at additional time periods after
application, and/or until disappearance of the reaction.