Efficacy of Different Hair and Skin Decontamination Strategies with Identification of Associated Hazards to First Responders

Abstract

Prompt disrobing and minimization of time to casualty decontamination are key to the effective treatment of individuals exposed to toxic chemicals. Established procedures for mass casualty decontamination that involve the deployment of equipment for showering with water (such as the ladder pipe system [LPS] and technical decontamination) necessarily introduce a short, but critical delay. The purpose of this study was to investigate the effectiveness of dry and wet decontamination approaches (individually and in combination) for removing a chemical warfare agent simulant from the hair and skin of human volunteers. A secondary aim was to quantify potential hazards arising from the decontamination processes. Volunteers were exposed to the simulant (mixture of methyl salicylate, fluorophore [curcumin] and mineral oil) as an aerosol within a custom-built dosing chamber. Three decontamination protocols (dry, LPS and technical decontamination) were applied in various sequences. The efficacy of the protocols was evaluated by whole-body fluorescent imaging and measurement of residual simulant recovered from the hair, skin, decontamination materials and air samples using liquid chromatography and thermal desorption gas chromatography. Dry decontamination before LPS or technical decontamination produced significant reductions in methyl salicylate skin contamination. The greatest reductions were seen with the Triple Protocol (dry, then LPS, then technical decontamination). Secondary sources of contamination (e.g. off-gassing of vapor and residue on wash cloths/towels) decreased following dry decontamination. The introduction of dry decontamination prior to wet forms of decontamination offers a simple strategy to initiate treatment at a much earlier opportunity, with a corresponding improvement in clinical outcomes. Our results confirm the value of a "Triple Protocol" response strategy based on the integration of dry and wet decontamination procedures. 3 Importantly, we highlight how these combined protocols may reduce toxicological risks downstream in the operational process.

A controlled cross-over study to evaluate the efficacy of improvised dry and wet emergency decontamination protocols for chemical incidents

“…Results from both MeS quantitation and UV imaging demonstrated that there was less simulant remaining on the skin following each of the improvised decontamination protocols compared to no-decontamination control, consistent with previous in vitro and human volunteer studies [ 3 – 7 ]. In addition, more simulant was removed from the skin when both improvised dry and wet decontamination were conducted in sequence compared to individually.…”

“…Whilst decontamination of skin using IOR methods has been subjected to controlled efficacy testing in vitro [ 3 , 4 ] little is known of the efficacy of these individual decontamination procedures when conducted in sequence. Although human volunteer studies have investigated the effectiveness of dry decontamination [ 5 – 7 ], improvised wet decontamination has yet to be investigated. Further, as mass decontamination strategies rely on implementation in series of dry followed by wet decontamination protocols as new resources become available at the scene of the incident, it is reasonable to explore the potential beneficial effects of sequential improvised dry and wet decontamination protocols, before these resources arrive.…”

“…To date, most studies of decontamination efficacy have focused on the amount of simulant remaining on the skin [ 5 – 7 ]. Whilst this is important for blister agents and preventing the uncontrolled spread of contaminants, for many hazardous chemicals the systemic availability is more important for predicting potential health consequences.…”

Laser scanning microscopy for control of skin decontamination efficacy from airborne particulates using highly absorbent textile nanofiber material in combination with PEG‐12 dimethicone

“…18 In a previous study, it was shown that the textile material was able to absorb a non-particulate test substance together with sebum from the skin surface. 25 It was hypothesized that a skin decontamination from particulate substances might be more challenging as the skin surface is not homogeneous but characterized by the presence of wrinkles, furrows, follicular orifices, and sweat glands, which serve as an appropriated reservoir for topically applied particulate substances. 26 Therefore, a viscous fluid will be applied to the skin, which extracts these particulate substances from the structures of the skin surface, allowing a facilitated removal by the highly absorbent textile material afterward.…”

“…For non‐particulate substances, it could already be shown that highly absorbent textile materials are well suited to efficiently remove substances from the skin23 by pressing them gently onto the skin without rubbing in order not to influence the integrity of the stratum corneum24 or to accelerate follicular penetration 18. In a previous study, it was shown that the textile material was able to absorb a non‐particulate test substance together with sebum from the skin surface 25…”