Efficacy of water-only or soap and water skin decontamination of chemical warfare agents or simulants using in vitro human models: A systematic review.

Water-only or water and soap are widely recommended as preferred solutions for dermal decontamination. However, limited efficacy data exist. We summarized experimental studies evaluating in vitro efficacy of water-only or soap and water in decontaminating chemical warfare agents (CWA) or their simulants from human skin models. Embase, Covidence®, MEDLINE, PubMed, Web of Science, and Google Scholar were searched for articles using water-only or soap and water decontamination methods for removal of CWA/CWA simulants in in vitro human skin models. Data extraction was completed from seven studies, yielding seven contaminants. Water-only decontamination led to partial decontamination in all skin samples (100%, n = 81/81). Soap and water decontamination led to partial decontamination in all skin samples (100%, n = 143/143). Four studies found decontamination to either paradoxically enhance absorption of contaminants or their penetration rates, known as the "wash-in" effect. Despite recommendations, water-only or water and soap decontamination were found to yield partial decontamination of CWA or their simulants in all human in vitro studies. Thus, more effective decontaminating agents are needed. Some studies demonstrated increased or faster penetration of chemicals following decontamination, which could prove deadly for agents such as VX, although these findings require in vivo validation. Heterogeneity in experimental setups limits interstudy comparison, and it remains unclear when water-only or water and soap are ideal decontaminants, which requires more studies. Pending manuscripts will summarize in vivo human and animal efficacy data. International harmonized efficacy protocol should enable more efficient public health decisions for evidence-based public health decisions.

Efficacy of soap and water based skin decontamination using in vivo animal models: a systematic review.

Water-only or soap and water solutions are considered a gold standard for skin decontamination. However, there is lack of conclusive data regarding their efficacy. The aim of this study was to summarize in vivo animal model data on skin decontamination using water-only, and/or soap and water. Covidence, Embase, MEDLINE, PubMed, Web of Science, and Google Scholar were searched to identify relevant articles using water-only or soap and water decontamination methods in in vivo animals. Data extraction was completed from studies, representing three animal models, and 11 contaminants. Results demonstrated water-only decontamination solutions led to complete decontamination in 3.1% (n = 16/524) protocols, incomplete decontamination in 90.6% (n = 475/524) of protocols, and mortality in 6.3% (n = 33/524) of protocols. Soap and water decontamination solutions resulted in complete decontamination in 6.9% (n = 8/116) protocols, incomplete decontamination in 92.2% (n = 107/116) of protocols, and mortality in 6.9% (n = 8/116) of protocols. Although water only, or soap and water is considered a gold standard for skin decontamination, most papers investigated found that water only, and soap and water provided incomplete decontamination. Due to the insufficient data, and limitations that hinder the applicability of available data, evidence indicates that more contemporary studies investigating skin decontamination are needed, and compared to other model species, including humans, when practical.