Evaluation of absorbent materials for use as ad hoc dry decontaminants during mass casualty incidents as part of the UK’s Initial Operational Response (IOR)

Abstract

The UK’s Initial Operational Response (IOR) is a revised process for the medical management of mass casualties potentially contaminated with hazardous materials. A critical element of the IOR is the introduction of immediate, on-scene disrobing and decontamination of casualties to limit the adverse health effects of exposure. Ad hoc cleansing of the skin with dry absorbent materials has previously been identified as a potential means of facilitating emergency decontamination. The purpose of this study was to evaluate the in vitro oil and water absorbency of a range of materials commonly found in the domestic and clinical environments and to determine the effectiveness of a small, but representative selection of such materials in skin decontamination, using an established ex vivo model. Five contaminants were used in the study: methyl salicylate, parathion, diethyl malonate, phorate and potassium cyanide. In vitro measurements of water and oil absorbency did not correlate with ex vivo measurements of skin decontamination. When measured ex vivo, dry decontamination was consistently more effective than a standard wet decontamination method (“rinse-wipe-rinse”) for removing liquid contaminants. However, dry decontamination was ineffective against particulate contamination. Collectively, these data confirm that absorbent materials such as wound dressings and tissue paper provide an effective, generic capability for emergency removal of liquid contaminants from the skin surface, but that wet decontamination should be used for non-liquid contaminants.

Further studies of the efficacy of military, commercial and novel skin decontaminants against the chemical warfare agents sulphur Mustard, Soman and VX

“…In recent years, there has been some scepticism over the suitability of aqueous-based decontamination systems, due to the phenomenon of a "wash-in" effect that can enhance chemical penetration through the skin (Idson, 1978;Moody and Nadeau, 1997;Zhai, 2002). Studies comparing the effectiveness of washing the skin or using absorbent materials resulted in better efficacy when absorbent materials were employed (Amlôt, 2017;Kassouf, 2017;Lademann, 2011). A further reason for developing a sponge or textile formulation is to mitigate possible issues surrounding the use of powder decontaminants, such as methods of application to the skin, containment and clear-up, in light of the dispersive properties of powders as well as their potential to be ACCEPTED MANUSCRIPT…”

“…It is well established that a major route of exposure to chemical warfare (CW) agents is via contact with the skin (Evison, 2002). The deliberate release of chemical warfare agents targeting civilian populations, exemplified by the sarin attacks in Tokyo (1995) and Syria (2014) (Eisenkraft, 2014;Okumura, 1996), has led to the continued development of more effective decontamination strategies focused on dealing with civilian mass-casualty incidents (Amlot, 2010;Amlôt, 2017;Kassouf, 2017;Matar, 2016).…”

“…The rationale behind this work was to discover alternative products that could be used at the scene of an incident, prior to the deployment of specialised services, in conjunction with or in lieu of showering. A recent study demonstrated the effectiveness of using any absorptive material for decontamination (Kassouf, 2017). However, the ability to retain these contaminants should be evaluated to prevent secondary contamination.…”

Chemical-Biological Terrorism and Its Impact on Children

“…83 In terms of wet versus dry decontamination, another study of absorbent materials in an ex vivo model indicated that dry decontamination was superior to wet methods for removing liquid contaminants but was not effective against particulate matter. 84 The consensus among investigators, however, is that time is the single most important factor in successful decontamination. 85 In most cases, decontamination is most successful if performed within minutes of exposure, which has the added benefit of mitigating the demand on health care facilities.…”

Optimization of Nonambulant Mass Casualty Decontamination Protocols as Part of an Initial or Specialist Operational Response to Chemical Incidents

“…The most pragmatic option is to use any readily available (nonproprietary) absorbent material to treat exposure to noncaustic liquids, such as chemical warfare agents and toxic industrial chemicals (4). Recent work has identified a number of such materials (5,6). However, while the IOR represents a substantial improvement in the initial clinical management of ambulant casualties, there is currently no comparable protocol for nonambulant patients.…”