Comparative assessment of the acute skin irritation potential of detergent formulations using a novel human 4-h patch test method

• Published in: Food and chemical toxicology Vol. 43; no. 12; pp. 1703 - 1712
• Main Authors: Robinson, Michael K., Kruszewski, Francis H., Al-Atrash, Jenan, Blazka, Mark E., Gingell, Ralph, Heitfeld, Fred A., Mallon, David, Snyder, Neil K., Swanson, Judith E., Casterton, Phillip L.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2005; New York, NY Elsevier Science
• Subjects: Adult; Aged; Biological and medical sciences; Dermatitis, Irritant - diagnosis; Dermatitis, Irritant - etiology; Detergent; Detergents - adverse effects; Female; Humans; Irritation; Male; Medical sciences; Middle Aged; Patch test; Patch Tests - methods; Sensitivity and Specificity; Skin; Skin Irritancy Tests - methods; Sodium Dodecyl Sulfate - adverse effects; Time Factors; Toxicology; Patch test; Skin; Detergent; Irritation; Human; Toxicity; Acute; Formulation; Test method; Patch; Skin test
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2005.05.012

Predictive skin irritation test methods, which do not require use of animals, are needed for the pre-market assessment of detergent formulations. The utility of a novel and ethical human acute skin irritation patch test method, originally developed for chemical skin irritation assessment, was evaluated. In this IRB-approved method, subjects were patched under occlusion for increasing periods of time up to 4 h in duration. The total incidence of positive skin reactions for test products was compared to a positive control (20% aqueous sodium dodecyl sulfate [SDS]). Acutely irritating formulas were defined as those showing a significantly increased or equal incidence of positive responders compared with that of SDS. The time of exposure required for 50% of subjects to show a positive skin reaction (TR 50 value) was calculated for each product and enabled test product comparisons within and between studies. Using this approach, 24 detergent formulations of various types were tested in seven individual studies. The skin irritation profiles were generally consistent within product types, which could be categorized as follows (by decreasing irritancy): mold/mildew removers (average TR 50 = 0.37 h) > disinfectants/sanitizers (0.64 h) > fabric softener concentrate (1.09 h) = aluminum wash (1.20 h) > 20% SDS (1.81 h) > liquid laundry detergents (3.48 h) > liquid dish detergents (4.16 h) = liquid fabric softeners (4.56 h) = liquid hand soaps (4.58 h) = shampoos (5.40 h) = hard surface cleaners (6.34 h) > powder automatic dish detergents (>16 h) = powder laundry detergents (>16 h). In addition to formulation effects, some seasonal effects were noted; particularly greater winter-time reactivity to 20% SDS and the hard surface cleaner and liquid laundry formulations. These results demonstrate the utility of this patch test method for the comparative skin irritation assessment of these different product types.