In Vitro Model for Decontamination of Human Skin

By: Hongbo Zhai, MD, University of California; and Howard I. Maibach, MD, University of California School of Medicine

Posted: April 1, 2009, from the April 2009 issue of Cosmetics & Toiletries.

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Based on the solubility of variables such as: contaminant and decontamination solutions, pH, the volume of decontamination, time of removal ratios, and physical enhancements (e.g., stripping, rubbing, adhesives; defining binding properties); robust decontamination agents/systems may be developable. For instance, a recent controlled experiment showed that water rinsing followed by topical calcium provided favorable results for hydrofluoric acid skin decontamination.¹¹ Note, however, details provided by Hall et al.¹² that may have significantly influenced the results; for example, the immediate use of a skin decontamination agent as a critical factor of efficacy following hydrofluoric acid exposure. In addition, adoption of splashing or acute burning models may also dramatically result in diametrically opposite outcomes with regard to decontamination agent potency. Wester et al.¹³ summarize the literature on skin decontamination, and Moody and Maibach¹⁴ the “wash-in” effect, or water-enhancing penetration.

Conclusion
The present model could be used as a rapid screening procedure for the development of effective decontamination agents. Taken together, the authors do not wish to overgeneralize these results. Yet, the in vitro human skin model may—when validated with other chemicals and subsequent in vivo verification^{2, 3}—provide more rapid enhancement of practical knowledge in this complex field.

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References
Send e-mail to: CT_author@allured.com.
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