Decontamination of Mass Casualties — Re-evaluating Existing Dogma

Management of decontamination in chemical accidents: a laboratory model

Rapid and efficient decontamination of the skin is a major task for emergency rescue services in the event of a chemical accident involving humans. While rinsing the skin with water (and soap) has been the standard procedure, some skepticism has developed in recent years regarding the situational suitability of this method. The efficacy of three different decontamination materials/techniques (Easyderm® cleaning cloth, water-soaked all-purpose sponge, rinsing with water) in removing Capsaicin, Bromadiolone, Paraquat and 2,2'-dichlorodiethylether (DCEE) from porcine skin was compared. Different cleaning motions (wiping, twisting, pressing) with the Easyderm® were evaluated for their effectiveness in removing Capsaicin from porcine skin. Finally, the impact of different exposure times of the skin to Capsaicin on the decontamination process were investigated. Contaminant recovery rates (CRRs) were analysed in the skin and in each decontamination material using high-performance-liquid-chromatography (HPLC; used for Capsaicin, Bromadiolone, Paraquat) or gas chromatography (GC; used for DCEE). Wiping the skin with the amphiphilic Easyderm® was most effective for decontamination of Capsaicin and DCEE, while the water rinsing method gave the best results for removing Paraquat and Bromadiolone. Both wiping with the Easyderm® and rotating the Easyderm® were significantly more effective in cleaning Capsaicin-contaminated skin than pressing the Easyderm® on the contamination area alone. Prolonged exposure times of the porcine skin to Capsaicin were associated with a decrease in efficacy of the following decontamination. Emergency rescue services should have materials available that can remove both hydrophilic and hydrophobic substances from skin. Since not all of our results for comparing different decontamination materials were as distinct as we expected, there are likely several other factors determining the efficacy of skin decontamination in some cases. Time is key; therefore, first responders should try to begin the decontamination process as soon as possible after arriving at the scene.

Cellulose-based sponge@ZIF-8 from waste straws for water disinfection

In this study, zeolitic imidazolate framework-8 (ZIF-8) nanoparticles can be readily in situ generated on the skeleton surface throughout the entire structure of cellulose-based sponges obtained from waste corn straws via a hydrothermal process. Taking natural corn straws as the basic ingredient, the Water Cellulose-based Sponge@ZIF-8 (WCSZ) composite inherits the highly porous structure of straws, which is beneficial for the movement of H₂O molecules in both horizontal and vertical directions. A robust H-bond topological network is weaved between abundant hydroxyl groups of the corn straw cell wall matrix and H₂O molecules in the honeycomb cellular structure. Based on the topological network, the WCSZ composite maintains sufficient mechanical compressibility and elasticity, which could sustain repeated squeezing without structural failure. The WCSZ composite can not only bear a compressive strain as high as 60% but also completely recover its original height after the load is removed, exhibiting excellent mechanical property. More importantly, the WCSZ composite also presents exceptional antibacterial activities after ZIF-8 nanoparticles were introduced (antibacterial rate: 99.9%). Consequently, the WCSZ composite is an ideal candidate for highly efficient elimination of bacteria as the reusable water treatment material.

A complete, evidence-based review on novichok poisoning based on epidemiological aspects and clinical management

Background: The whole world has learned about the existence of a highly toxic neuro-paralytic substance called Novichok. A wide range of neuro-paralytic toxins were used during the wars of decades ago, which also had harmful and irreversible effects. Fortunately, the establishment of conventions prohibiting the use of these weapons prevented the adverse clinical consequences of these compounds. What we did in the present study was to evaluate the clinical features of Novichok, how to manage exposure to it, and to evaluate the prognostic aspects associated with this poisoning agent. Methods: The manuscript especial databases including Medline, Web of knowledge, Google scholar, and Scopus were deeply searched by the two blinded investigators for all eligible studies based on the considered keywords. Initially 98 articles were initially collected by database searching that considering eligibility criteria, 83 articles were finally eligible for the final assessment. There is a lack of clinical trials and case-cohort studies on general population about treatment and side effects when it comes to human nerve agents and most of the data in our search is based on animal studies. Results: In evaluating various clinical, auto physiological and prognostic aspects of exposure to these substances, special attention was necessary to the following points. First, Novichok agents are considered more potent than other toxic agents. Pathophysiologically, these agents irreversibly bind acetylcholinesterase and produce a rapid cholinergic toxidrome which is responsible for the clinical manifestations as well as the potential dangerous and life threatening side effects caused by these agents. Uniquely, these agents are thought to also target every neuron in the central and peripheral nervous system. As a managerial and therapeutic approach, early and timely treatment of its related complication along with prevents massive exposure and decontamination in addition to rapid resuscitation can prohibit debilitating neuropathy and death due to facing it. Conclusion: The present review highlights the importance of recognizing the potential acute toxic effects of Novichok agents, diagnostic and therapeutic approaches (life-saving antidotal therapy) to complications and ultimately the application of guidelines to improve the prognosis of exposure to these agents for both victims and medical community.

Efficacy of water-based skin decontamination of occupational chemicals using in vitro human skin models: a systematic review

Percutaneous absorption of chemicals is a potential route of topical and systemic toxicity. Skin decontamination interrupts this process by removing contaminants from the skin surface. Decontamination using water-only or soap and water solutions is the current gold standard despite limited efficacy data. A summary of studies evaluating their efficacy in decontaminating occupational contaminants from in vitro human skin models is presented. Embase, MEDLINE, PubMed, Web of Science, and Google Scholar were searched for relevant articles and data extracted from 15 investigations that reported on 21 occupational contaminants, which were further classified as industrial chemicals, drugs, or pesticides. Water-only decontamination yielded no response in 4.3% (n = 6/140) and partial decontamination in 95.7% (n = 134/140) of skin samples. Soap and water decontamination yielded complete decontamination in 4.9% (n = 13/264) and partial decontamination in 95.1% (n = 251/264) of skin samples. Four studies (26.7%, n = 4/15) reported increased penetration rates or skin concentration of contaminants following decontamination, demonstrating a "wash-in" effect. Varying study methodologies hinder our ability to compare data and determine when water alone or soap and water are best used. International harmonized efficacy protocol might enhance our decontamination understanding and enable a more customized approach to decontamination clinical practice and research.

Factors Affecting the Decontamination Process in Hospitals in Saudi Arabia

Introduction

Hospitals face various types of disasters that require either decontamination or disinfection interventions. These contaminants can be chemical, biological, radioactive, or infectious, such as COVID-19. Further, there are few studies in the literature on factors affecting decontamination in hospitals in Saudi Arabia.

Methods

Approximately 157 healthcare providers (doctors, nurses, and other specialists) participated in this study. Principle component analysis was used to explore three factors in Saudi Arabia that affect the ability of healthcare providers to decontaminate appropriately.

Results

Three factors were extracted: (1) having adequate skills to perform decontamination, (2) being adequately prepared for decontamination before a disaster occurs, and (3) organizational barriers to decontamination. There was a positive correlation between the skills and preparedness and a negative correlation between barriers and both skills and preparedness.

Discussion

It is essential to prepare for decontamination during disasters more effectively and to ensure that all healthcare providers have the requisite skills. Moreover, barriers to decontamination must be investigated thoroughly to improve implementation.

Understanding skin absorption of common aldehyde vapours from exposure during hazardous material incidents

The toxic release of aldehyde vapours during a hazardous material (HAZMAT) incident primarily results in respiratory concerns for the unprotected public. However, skin absorption may be an important concurrent exposure route that is poorly understood for this scenario. This study provides experimental data on the skin absorption properties of common aldehydes used in industry, including acetaldehyde, acrolein, benzaldehyde and formaldehyde, in gaseous or vapour form using an adapted in vitro technique. Two of the four tested aldehydes were found to penetrate the skin in appreciable amounts following 30-min exposure at HAZMAT relevant atmospheric concentrations: acetaldehyde (5.29 ± 3.24 µg/cm²) and formaldehyde (3.45 ± 2.58 µg/cm²). Whereas only low levels of acrolein (0.480 ± 0.417 µg/cm²) and benzaldehyde (1.46 ± 0.393 µg/cm²) skin penetration was noted. The aldehydes demonstrated differing levels of interaction with fabric. Formaldehyde and acetaldehyde adsorbed strongly to denim, whereas benzaldehyde and acrolein displayed no sink properties. However, denim was shown to be an initial protective barrier and reduced penetration outcomes for all aldehydes. This study provides important information to assist first responders and confirms the relevance of using physicochemical properties (e.g. solubility, molecular weight, partition coefficient) to predict skin permeation potential in the absence of empirical data during HAZMAT incidents involving different types of aldehydes.

Emergency Department Response to Chemical, Biological, Radiological, Nuclear, and Explosive Events: A Systematic Review

Introduction

A Chemical, Biological, Radiological, Nuclear, and explosive (CBRNe) event is an emergency which can result in injury, illness, or loss of life. The emergency department (ED) as a health system is at the forefront of the CBRNe response with staff acting as first receivers. Emergency departments are under-prepared to respond to CBRNe events - recognizing key factors which underlie the ED CBRNe response is crucial to provide evidence-based knowledge to inform policies and, most importantly, clinical practice.

Problem

Challenges in detection, decontamination, and diagnosis are associated with the ED CBRNe response when faced with self-presenting patients.

Methods

A systematic review was carried out in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). An in-depth search strategy was devised to identify studies which focused on the ED and CBRNe events. The inclusion criteria were stringent in terms of the environment (ED), participants (first receivers), situation (CBRNe response), and actions (detection, decontamination, and diagnosis). Fifteen databases and topic-specific journals were searched. Studies were critically appraised using the Mixed Methods Appraisal Tool (MMAT). Papers were thematically coded and synthesized using NVivo 10 (QSR International Ltd, Melbourne, Australia).

Results

Sixty-seven full-text papers were critically appraised using the MMAT; 70% were included (n = 60) as medium- or high-quality studies. Data were grouped into four themes: preparedness, response, decontamination, and personal protective equipment (PPE) problems.

Discussion

This study has recognized the ED as a system which depends on four key factors - preparedness, response, decontamination, and PPE problems - which highlight challenges, uncertainties, inconsistencies, and obstacles associated with the ED CBRNe response. This review suggests that response planning and preparation should be considered at three levels: organizational (policies and procedures); technological (decontamination, communication, security, clinical care, and treatment); and individual (willingness to respond, PPE, knowledge, and competence). Finally, this study highlighted that there was a void specific to detection and diagnosis of CBRNe exposure on self-presenting patients in the ED.

Conclusion:

The review identified concerns for both knowledge and behaviors which suggests that a systems approach would help understand the ED response to CBRNe events more effectively. The four themes provide an evidence-based summary for the state of science in ED CBRNe response, which can be used to inform future policies and clinical procedures.

RazakS,HignettS,BarnesJ.Emergency department response to chemical, biological, radiological, nuclear, and explosive events: a systematic review.Prehosp Disaster Med.2018;33(5):543–549.

Empirical data in support of a skin notation for methyl chloride

This article presents the first empirical experimental data on the skin absorption of methyl chloride gas using an in vitro technique and human skin. Methyl chloride is a commonly used industrial agent that is known to be an inhalational hazard but is also reported to be absorbed through human skin in amounts that contribute substantially to systemic intoxication. As a result, is has been assigned a skin notation by the ACGIH. Other than predictive models, there is a general paucity of experimental data on the skin absorption of methyl chloride and therefore a distinct lack of empirical evidence in the open literature to support the assignment of a skin notation for this chemical. This study found that methyl chloride permeates through human epidermis when exposed at high atmospheric concentrations within relatively short timeframes. Therefore, providing important initial empirical evidence in support of the assignment of a skin notation.

Iron-montmorillonite clays as active sorbents for the decontamination of hazardous chemical warfare agents

Montmorillonite clay was modified to introduce iron species and acid sites in the interlayer space, aiming to obtain a catalyst with oxidising and acid properties for the degradation of chemical warfare agents.

Dermal absorption of fumigant gases during HAZMAT incident exposure scenarios—Methyl bromide, sulfuryl fluoride, and chloropicrin

Accidental or intentional releases of toxic gases or vapors are the most common occurrence in hazardous material (HAZMAT) incidents that result in human injuries. The most serious hazard from exposure to gases or vapors is via the respiratory system. Dermal uptake, as a secondary route, is still a concern, most acutely for the unprotected public. There is a limited evidence base describing skin absorption of toxic gases and vapors in HAZMAT exposure scenarios, which are relatively brief compared with traditional test periods for skin absorption studies. We describe research designed to provide experimental data to support decision-making by first responders regarding skin decontamination in HAZMAT-focused exposure scenarios involving toxic gases. We present findings for three common fumigants, methyl bromide, sulfuryl fluoride, and chloropicrin assessed using an Organization for Economic Co-operation and Development in vitro toxicology protocol utilizing human skin and gas/vapor exposures. Results indicate that for atmospheric concentrations that would be lethal via inhalation (LCLo), intact skin provides an excellent barrier to exposures up to 30 min, with little influence of common clothing fabric and high temperature and humidity conditions. The findings may challenge the current HAZMAT dogma requiring mass personal decontamination by strip and shower for short-term exposures to sulfuryl fluoride and chloropicrin gas/vapor.

Hydrogen sulphide and phosphine interactions with human skin in vitro

Accidental or intentional releases of toxic gases can have significant public health consequences and emergency resource demands. Management of exposed individuals during hazardous material incidents should be risk and evidence based, but there are knowledge gaps in relation to dermal absorption of gases and management advice for potentially exposed individuals. Using a modified Organization for Economic Co-operation and Development (OECD) in vitro toxicology protocol with human donor skin, this article reports on two common and odorous chemicals, hydrogen sulphide and phosphine. Results show that undamaged human skin provides a good barrier to hydrogen sulphide (up to 800 ppm) and phosphine (up to 1000 ppm) penetration for up to 30 min exposures, with little variability in the presence of clothing or in elevated temperature and humidity conditions. A practical guideline template for skin decontamination has been developed, and implications of the research for first responders are outlined.

Mass Casualty Decontamination in a Chemical or Radiological/Nuclear Incident with External Contamination: Guiding Principles and Research Needs

Hazardous chemical, radiological, and nuclear materials threaten public health in scenarios of accidental or intentional release which can lead to external contamination of people.  Without intervention, the contamination could cause severe adverse health effects, through systemic absorption by the contaminated casualties as well as spread of contamination to other people, medical equipment, and facilities.  Timely decontamination can prevent or interrupt absorption into the body and minimize opportunities for spread of the contamination, thereby mitigating the health impact of the incident.  Although the specific physicochemical characteristics of the hazardous material(s) will determine the nature of an incident and its risks, some decontamination and medical challenges and recommended response strategies are common among chemical and radioactive material incidents.  Furthermore, the identity of the hazardous material released may not be known early in an incident.  Therefore, it may be beneficial to compare the evidence and harmonize approaches between chemical and radioactive contamination incidents.  Experts from the Global Health Security Initiative’s Chemical and Radiological/Nuclear Working Groups present here a succinct summary of guiding principles for planning and response based on current best practices, as well as research needs, to address the challenges of managing contaminated casualties in a chemical or radiological/nuclear incident.

Decontamination Efficacy and Skin Toxicity of Two Decontaminants against Bacillus anthracis

Decontamination of bacterial endospores such as Bacillus anthracis has traditionally required the use of harsh or caustic chemicals. The aim of this study was to evaluate the efficacy of a chlorine dioxide decontaminant in killing Bacillus anthracis spores in solution and on a human skin simulant (porcine cadaver skin), compared to that of commonly used sodium hypochlorite or soapy water decontamination procedures. In addition, the relative toxicities of these decontaminants were compared in human skin keratinocyte primary cultures. The chlorine dioxide decontaminant was similarly effective to sodium hypochlorite in reducing spore numbers of Bacillus anthracis Ames in liquid suspension after a 10 minute exposure. After five minutes, the chlorine dioxide product was significantly more efficacious. Decontamination of isolated swine skin contaminated with Bacillus anthracis Sterne with the chlorine dioxide product resulted in no viable spores sampled. The toxicity of the chlorine dioxide decontaminant was up to two orders of magnitude less than that of sodium hypochlorite in human skin keratinocyte cultures. In summary, the chlorine dioxide based decontaminant efficiently killed Bacillus anthracis spores in liquid suspension, as well as on isolated swine skin, and was less toxic than sodium hypochlorite in cultures of human skin keratinocytes.

Self-care Decontamination within a Chemical Exposure Mass-casualty Incident

Growing awareness and concern for the increasing frequency of incidents involving hazardous materials (HazMat) across a broad spectrum of contaminants from chemical, biological, radiological, and nuclear (CBRN) sources indicates a clear need to refine the capability to respond successfully to mass-casualty contamination incidents. Best results for decontamination from a chemical agent will be achieved if done within minutes following exposure, and delays in decontamination will increase the length of time a casualty is in contact with the contaminate. The findings presented in this report indicate that casualties involved in a HazMat/CBRN mass-casualty incident (MCI) in a typical community would not receive sufficient on-scene care because of operational delays that are integral to a standard HazMat/CBRN first response. This delay in response will mean that casualty care will shift away from the incident scene into already over-tasked health care facilities as casualties seek aid on their own. The self-care decontamination protocols recommended here present a viable option to ensure decontamination is completed in the field, at the incident scene, and that casualties are cared for more quickly and less traumatically than they would be otherwise. Introducing self-care decontamination procedures as a standard first response within the response community will improve the level of care significantly and provide essential, self-care decontamination to casualties. The process involves three distinct stages which should not be delayed; these are summarized by the acronym MADE: Move/Assist, Disrobe/Decontaminate, Evaluate/Evacuate.

MonteithRG, PearceLDR. Self-care decontamination within a chemical exposure mass-casualty incident. Prehosp Disaster Med. 2015;30(3):1–9.

Chlorine and hydrogen cyanide gas interactions with human skin: in vitro studies to inform skin permeation and decontamination in HAZMAT incidents

Accidental or intentional toxic gas releases may result in significant public health and psychological consequences. Management of exposed individuals during HAZMAT incidents should be risk-based and supported by a suitable scientific evidence base. There appear to be large evidence gaps in relation to dermal absorption of gases, as well as management advice for potentially exposed individuals. Chlorine and hydrogen cyanide are two common HAZMAT gases and this paper addresses the need for experimental data tailored to HAZMAT scenarios and first responders. In addition to time variations of gas concentration, the modifying effects of clothing, temperature, and oil-based sunscreen on epidermal absorption and penetration are assessed. Results for chlorine show little penetration up to 500 ppm but with small enhancing effects due to heavy cotton and oil-based sunscreen. Hydrogen cyanide up to 800 ppm shows minor penetration consistent with previous studies, with little variability in the presence of sunscreen and clothing. Practical guidelines to support the decision-making of emergency responders with regard to personal decontamination have been derived.

Application of skin contamination studies of ammonia gas for management of hazardous material incidents

In an atmospheric HAZMAT release unprotected public dermal exposure is often of short duration, but with potential secondary exposure if not decontaminated promptly. Mass decontamination is resource intensive and needs to be justified. For many HAZMAT agents there is no evidence-base on which to provide guidance on decontamination, particularly for non-symptomatic worried well. It is important to understand the influence of street clothing and environmental and other factors. Ammonia is a common HAZMAT agent and was selected for in vitro human skin studies of absorption, penetration and off-gassing at test concentrations up to 2000 ppm, incorporating primary and secondary exposure combinations up to 60 min. Intact skin provided a good barrier to ammonia penetration. Heavy street clothing such as denim was found to act as an initial barrier to skin absorption but subsequently as a reservoir for secondary exposure, under variable temperature and humidity conditions. Rapid off-gassing was observed for lighter fabrics including polyester and cotton. The findings here have been summarized as a set of practical guidelines for emergency responders who are required to make decisions about ammonia decontamination including for non-symptomatic individuals. This evidence-based diagrammatic approach allows for specific actions based on different atmospheric ammonia concentrations and other parameters.

Skin decontamination

Skin decontamination is the primary intervention needed in chemical, biological and radiological exposures, involving immediate removal of the contaminant from the skin performed in the most efficient way. The most readily available decontamination system on a practical basis is washing with soap and water or water only. Timely use of flushing with copious amounts of water may physically remove the contaminant. However, this traditional method may not be completely effective, and contaminants left on the skin after traditional washing procedures can have toxic consequences. This article focuses on the principles and practices of skin decontamination.

Decontamination of Multiple Casualties Who Are Chemically Contaminated: A Challenge for Acute Hospitals

Patients who have been contaminated by chemical compounds present a number of difficulties to emergency departments, in particular, the risk of secondary contamination of healthcare staff and facilities. The Department of Health in the United Kingdom has provided equipment to decontaminate chemically contaminated casualties who present at emergency departments. The capacity of this equipment is limited, and although both the ambulance and fire services have equipment to cope with mass casualties at the scene of a chemical incident, there is still the possibility that acute hospitals will be overwhelmed by large numbers of self-presenting patients. The risks and potential consequences of this gap in resilience are discussed and a number of possible practical solutions are proposed.

Decontamination of Human and Rabbit Skin Experimentally Contaminated with 99mTc Radionuclide Using the Active Components of “Shudhika”—a Skin Decontamination Kit

Introduction

Radioactive contamination can occur as a result of accidental or intentional release of radioactive materials (RM) into the environment. RM may deposit on clothing, skin, or hair. Decontamination of contaminated persons should be done as soon as possible to minimize the deleterious health effects of radiation. The goal of this study was to evaluate the decontamination efficiency (for residual contaminant) of the active components of “Shudhika,” an indigenously developed skin decontamination kit. The study kit is for external radioactive decontamination of intact skin.

Methods

Decontamination efficiency was evaluated on the skin surface of rabbit (n = 6) and human volunteers (n = 13). 99mTc sodium pertechnetate (200-250 μCi) was used as the radio-contaminant. Skin surface area (5 × 5 cm2) of thoracic abdominal region of the rabbit and the forearm and the palm of human volunteers were used for the study. Decontamination was performed by using cotton swabs soaked with chemical decontamination agents of the kit.

Results

Decontamination efficiency (% of the contaminant removed) was calculated for each component of the study. Overall effectiveness of the kit was calculated to be 85% ± 5% in animal and 92% ± 3% in human skin surfaces. Running water and liquid soap with water was able to decontaminate volunteers' hand and animal skin up to 70% ± 5%. Chemical decontamination agents were applied only for trace residues (30% ± 5%). Efficiency of all the kit components was found up to be 20% ± 3% (animal) and 28% ± 2 (human), respectively. Residual contamination after final decontamination attempt for both the models was observed to be 12% ± 3% and 5% ± 2%. After 24 and 48 hours of the decontamination procedure, skin was found to be normal (no redness, erythema and edema were observed).

Conclusion

Decontaminants of the study kit were effective in removal of localized radioactive skin contamination when water is ineffective for further decontamination. By using the chemical decontaminants of the study kit, the use of water and radioactive waste generation could be reduced. Cross-contamination could also be avoided. During radiologic emergencies where water may be radioactively contaminated, the study kit could be used.

Rana S, Dutta M, Soni NL, Chopra MK, Kumar V, Goel R, Bhatnagar A, Sultana S, Sharma RK. Decontamination of human and rabbit skin experimentally contaminated with 99mTc radionuclide using the active components of “Shudika”—a skin decontamination kit. Prehosp Disaster Med. 2012;27(2):1-5.

Chemical warfare agents

Among the Weapons of Mass Destruction, chemical warfare (CW) is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided.

Comparative analysis of showering protocols for mass-casualty decontamination

A well-established provision for mass-casualty decontamination that incorporates the use of mobile showering units has been developed in the UK. The effectiveness of such decontamination procedures will be critical in minimizing or preventing the contamination of emergency responders and hospital infrastructure. The purpose of this study was to evaluate three empirical strategies designed to optimize existing decontamination procedures: (1) instructions in the form of a pictorial aid prior to decontamination; (2) provision of a washcloth within the showering facility; and (3) an extended showering period. The study was a three-factor, between-participants (or "independent") design with 90 volunteers. The three factors each had two levels: use of washcloths (washcloth/no washcloth), washing instructions (instructions/no instructions), and shower cycle duration (three minutes/six minutes). The effectiveness of these strategies was quantified by whole-body fluorescence imaging following application of a red fluorophore to multiple, discrete areas of the skin. All five showering procedures were relatively effective in removing the fluorophore "contaminant", but the use of a cloth (in the absence of instructions) led to a significant ( appox. 20%) improvement in the effectiveness of decontamination over the standard protocol (p <0.05). Current mass-casualty decontamination effectiveness, especially in children, can be optimized by the provision of a washcloth. This simple but effective approach indicates the value of performing controlled volunteer trials for optimizing existing decontamination procedures.

Chemical agent simulant release from clothing following vapor exposure

OBJECTIVES

Most ambulatory victims of a terrorist chemical attack will have exposure to vapor only. The study objective was to measure the duration of chemical vapor release from various types of clothing.

METHODS

A chemical agent was simulated using methyl salicylate (MeS), which has similar physical properties to sulfur mustard and was the agent used in the U.S. Army's Man-In-Simulant Test (MIST). Vapor concentration was measured with a Smiths Detection Advanced Portable Detector (APD)-2000 unit. The clothing items were exposed to vapor for 1 hour in a sealed cabinet; vapor concentration was measured at the start and end of each exposure. Clothing was then removed and assessed every 5 minutes with the APD-2000, using a uniform sweep pattern, until readings remained 0.

RESULTS

Concentration and duration of vapor release from clothing varied with clothing composition and construction. Lightweight cotton shirts and jeans had the least trapped vapor; down outerwear, the most. Vapor concentration near the clothing often increased for several minutes after the clothing was removed from the contaminated environment. Compression of thick outerwear released additional vapor. Mean times to reach 0 ranged from 7 minutes for jeans to 42 minutes for down jackets.

CONCLUSIONS

This simulation model of chemical vapor release demonstrates persistent presence of simulant vapor over time. This implies that chemical vapor may be released from the victims' clothing after they are evacuated from the site of exposure, resulting in additional exposure of victims and emergency responders. Insulated outerwear can release additional vapor when handled. If a patient has just moved to a vapor screening point, immediate assessment before additional vapor can be released from the clothing can lead to a false-negative assessment of contamination.

Mustard gas or sulfur mustard: an old chemical agent as a new terrorist threat

Sulfur mustard is a member of the vesicant class of chemical warfare agents that causes blistering to the skin and mucous membranes. There is no specific antidote, and treatment consists of systematically alleviating symptoms. Historically, sulfur mustard was used extensively in inter-governmental conflicts within the trenches of Belgium and France during World War I and during the Iran-Iraq conflict. Longitudinal studies of exposed victims show that sulfur mustard causes long-term effects leading to high morbidity. Given that only a small amount of sulfur mustard is necessary to potentially cause an enormous number of casualties, disaster-planning protocol necessitates the education and training of first-line healthcare responders in the recognition, decontamination, triage, and treatment of sulfur mustard-exposed victims in a large-scale scenario.

First-receiver hospital decontamination: an 8-step approach to a progressive and practical program

The effectiveness of hospital decontamination programs begins with planning, preparation, and practice. A well-thought-out hospital decontamination program encompasses complexities that are not always apparent. In disaster situations, the victim, hospital, patients, and staff are placed at serious risk if untrained, unprepared employees perform emergency decontamination procedures at the hospital-receiving site. The authors describe 8 steps to developing an emergency preparedness program and team with decontamination capabilities to facilitate emergency response in the first-receiver hospital.

Bringing Order Out of Chaos: Effective Strategies for Medical Response to Mass Chemical Exposure

An accident or a deliberate terrorism attack releasing hazardous chemicals will create chaos, confusion, and seeming unpredictability that complicates the emergency response. Clinicians are challenged to urgently treat patients needing care, even before a chemical is confirmed. Emergency response planning that focuses on preparing for predictable challenges to the health care system and applies basic toxicologic principles to clinical decision-making can bring a sense of order to the chaos and provide medical care that will be best for the most victims of an incident.

Toxicological aspects of preparedness and aftercare for chemical-incidents

The threat of using chemical warfare agents still exists despite the 1993 Chemical Weapons Convention. Preparedness for attacks with chemical agents has become an important issue of national security programs. It can be anticipated that toxicologists will be increasingly involved in preparedness programs of their institutions and of the government, no matter whether they work in agencies, industry or universities. Toxicologists must get prepared to give fast and reliable advice in the case of an attack, a sabotage or an accident with release of toxic chemicals. They should be familiar with the principles of hazard management and with incident command structures and cooperate with first responders of other organizations involved such as fire department and medical emergency teams already in the planning phase. In the emergency planning phase, toxicologists are expected to help identifying possible hazards. Moreover, they consult public health services with regard to toxicosurveillance and advice hospitals regarding antidotes, decontamination procedures and shelters. They may be involved in the procurement of antidotes and of protective equipment and will support qualified analytical laboratories. In the response phase, toxicologists must be ready to gain and to interpret analytical data, to support the medical care of poisoned victims and to provide repeated risk assessment reports. This requires an on-scene access to databases and registries. The aftercare phase includes the identification of exposed persons, mapping of contaminated areas, organization of decontamination measures and the release of areas. A medical study may be initiated to observe long-term health effects. Good cooperation between regulatory and clinical toxicologists, specific education of toxicologist in the field of chemical emergencies and regular trainings are essential elements of good preparedness.

Decontamination

Decontamination is the removal or reduction of chemical, biologic, or radiologic agents from the patient's skin, mucosa, lungs, and gastrointestinal tract. Decontamination is an important step in decreasing the clinical effects of the agent on the patient, as well as protecting coworkers from exposure. For most agents and the vast majority of scenarios, the removal of clothing and a simple 5- to 6-minute shower with soap and water is sufficient to eliminate the risks to the patient and hospital staff. In rare circumstances, additional steps in decontamination including gastric lavage, broncho-alveolar lavage, surgical removal of wound foreign bodies, and administration of activated charcoal, polyethylene glycol electrolyte solution, and radioisotope binding agents, may be necessary.