Biologists napping while work militarized.

As researchers discover more agents that alter mental states, the Chemical Weapons Convention needs modification to help ensure that the life sciences are not used for hostile purposes, says Malcolm Dando.

Evaluation of CS (o-chlorobenzylidene malononitrile) concentrations during U.S. Army mask confidence training.

All soldiers in the U.S. Army are required to complete mask confidence training with o-chlorobenzylidene malononitrile (CS). To instill confidence in the protective capability of the military protective mask, CS is thermally dispersed in a room where soldiers wearing military protective masks are required to conduct various physical exercises, break the seal of their mask, speak, and remove their mask. Soldiers immediately feel the irritating effects of CS when the seal of the mask is broken, which reinforces the mask's ability to shield the soldier from airborne chemical hazards. In the study described in this article, the authors examined the CS concentration inside a mask confidence chamber operated in accordance with U.S. Army training guidelines. The daily average CS concentrations ranged from 2.33-3.29 mg/m3 and exceeded the threshold limit value ceiling, the recommended exposure limit ceiling, and the concentration deemed immediately dangerous to life and health. The minimum and maximum CS concentration used during mask confidence training should be evaluated.

Acute laryngeal and bronchial obstruction after CS (o-chlorobenzylidenemalononitrile) gas inhalation.

CS gas (o-chlorobenzylidenemalononitrile) is one of the most commonly used riot agents. It can create excessive tearing, conjunctivitis, uncontrolled blinking (blepharospasm) and a sensation of burning and pain at initial exposure. Pulmonary edema (ARDS) and/or diffuse airway lesions on human would be lethal after CS inhalation. We report a case with acute laryngeal and bronchial obstruction due to vocal cord edema and extensive crusting at glottic level, trachea and bronchi. The CS gas was sprayed in a 6 x 6 m(2) closed room, and she was exposed to increased concentration of the gas for 10 s. Surprisingly, her initial symptoms were raised 21 days after CS spray exposure.

Respiratory agents: irritant gases, riot control agents, incapacitants, and caustics.

There are many chemical respiratory agents suitable for use by terrorists. They are the oldest chemical agents used and have caused the most casualties throughout the 20th century. Many are available in large quantities for industrial use and are susceptible to potential sabotage. This paper will concentrate on respiratory agents that are readily available and have the potential to cause a large number of casualties and panic. These agents have a lower rate of lethality when compared to other chemical agents but could produce many casualties that may overwhelm the emergency medical system.

The pathology of lethal exposure to the Riot Control Agents: towards a forensics-based methodology for determining misuse.

The aim of this is to review deaths associated with the use of Riot Control Agents (RCAs) and to assess how the presenting pathologies is such cases may better inform cause of death conclusions upon autopsy. We also sought to present which additional steps should be added to the Minnesota protocol and the European harmonization of medico-legal autopsy rules in suspected cases of deaths associated with the use of RCAs. We included 10 lethal cases in our study. In three cases, RCAs were found to be the sole cause of death, in three cases RCAs were ruled a secondary cause of death due asphyxia or asthma subsequent to exposure to RCAs and in four cases RCAs were contributory factors to death. In three cases the responsible agents were identified as Chloroacetophenone (CN), Chlorobenzylidene malononitrile (CS) and Oleoresin capsicum (OC) and in the remaining 7 cases, the agent was OC alone. As there are no specific findings in suspected cases of death associated with RCA use, establishing cause of death and whether RCAs are the sole cause or only a contributory factor will be based on the elimination of other possible causes of death. For this reason, a specifically structured autopsy is essential. This specifically structured autopsy should contain basic principles of the Minnesota Protocol and the European harmonization of medico-legal autopsy rules with the following additional steps taken: examination of clothing, eyes, and skin; examination of pharyngeal, tracheobronchial, and eusophegeal mucosas; and a thorough recording of the steps taken by the party conducting the arrest, including other possible causes of in-custody death, as well as a detailed medical history of the deceased.

Short-term and long-term physical effects of exposure to CS spray.

CS gas (2-chlorobenzylidene malonitrile) is widely used in an incapacitant spray that causes intense lacrimation, blepharospasm and burning sensations in the throat and nose. Questions have been raised about its safety. We obtained information on short-term and long-term symptoms, and performed ear, nose and throat examinations and respirometry at 8-10 months, in 34 young adults who had been exposed to CS spray in a confined space during a confrontation with police. The group was subdivided into those who had been sprayed directly on the face (n=10) and those exposed indirectly. At one hour, all but 2 individuals still had symptoms; respiratory and oral symptoms were significantly more prevalent in the directly exposed group. At one month, only oral symptoms were significantly more prevalent. At 8-10 months, symptoms were still reported but there were no differences between the groups and clinical examinations revealed no specific abnormalities. There was no convincing evidence of long-term physical sequelae from exposure to CS spray.

O-chlorobenzylidene malononitrile (CS riot control agent) associated acute respiratory illnesses in a U.S. Army Basic Combat Training cohort.

Acute respiratory illnesses (ARIs) are among the leading causes for hospital visits in U.S. military training populations and historically peak during U.S. Army Basic Combat Training (BCT) following mandatory exposure to the riot control agent o-chlorobenzylidene malononitrile (CS). This observational prospective cohort studied the association between CS exposures and ARI-related health outcomes in 6,723 U.S. Army recruits attending BCT at Fort Jackson, South Carolina from August 1 to September 25, 2012 by capturing and linking the incidence of ARI before and after the mask confidence chamber to CS exposure data. Recruits had a significantly higher risk (risk ratio = 2.44; 95% confidence interval = 1.74, 3.43) of being diagnosed with ARI following exposure to CS compared to the period of training preceding exposure, and incidence of ARI after CS exposure was dependent on the CS exposure concentration (p = 0.03). There was a significant pre-/postexposure ARI difference across all CS concentration levels (p < 0.01), however, no significant differences were detected among these rate ratios (p = 0.72). As CS exposure is positively associated with ARI health outcomes in this population, interventions designed to reduce respiratory exposures could result in decreased hospital burden and lost training time in the U.S. Army BCT population.

Analysis of clothing and urine from Moscow theatre siege casualties reveals carfentanil and remifentanil use.

On October 26, 2002, Russian Special Forces deployed a chemical aerosol against Chechen terrorists to rescue hostages in the Dubrovka theatre. Its use confirmed Russian military interest in chemicals with effects on personnel and caused 125 deaths through a combination of the aerosol and inadequate medical care. This study provides evidence from liquid chromatography-tandem mass spectrometry analysis of extracts of clothing from two British survivors, and urine from a third survivor, that the aerosol comprised a mixture of two anaesthetics--carfentanil and remifentanil--whose relative proportions this study was unable to identify. Carfentanil and remifentanil were found on a shirt sample and a metabolite called norcarfentanil was found in a urine sample. This metabolite probably originated from carfentanil.

Unintended cutaneous reactions to CS spray.

CS spray (2-chlorobenzylidene malononitrile 5% w/v in methyl isobutyl ketone) has been used by the police force in the UK as an incapacitant for nearly a decade. It causes a number of well-recognized cutaneous reactions, which are generally regarded as short-lived. These include skin burning, erythema and blistering. However, a range of unpredictable cutaneous reactions to CS spray may also occur. We have found contact allergy, leukoderma, initiation or exacerbation of seborrhoeic dermatitis, and aggravation of rosacea following CS spray exposure in 6 police officers and 1 doorman. These skin reactions have required long-term changes in working practice for the affected individuals. Police officers may have repeated exposure to CS spray during their training and in their work, and designated police officers carry CS spray canisters daily in the line of duty. They may therefore be at greater risk of exposure to CS spray and its unintended effects than many assailants.

Unexpected "gas" casualties in Moscow: a medical toxicology perspective.

In October 2002, the Russian military used a mysterious "gas" to incapacitate Chechen rebels at a Moscow theater. Despite increased interest in the potential use of lethal chemical weapons in recent years, the medical community has paid little attention to the development of incapacitating, calmative, and "less than lethal" technologies. In this analysis, we review the events surrounding the use of a calmative "gas" during the Russian military action and discuss what is currently known about fentanyl derivatives, their aerosolization, and the rationale for their use as incapacitating agents. Collectively, the available evidence strongly suggests that a combination of a potent aerosolized fentanyl derivative, such as carfentanil, and an inhalational anesthetic, such as halothane, was used. The paper also assesses potential errors leading to the loss of a substantial number of hostages. Several lessons can be learned from this surprising and novel use of an incapacitating gas.

The effects of external ocular irritation on intraocular pressure.

Riot control agents (tear gases) cause intense eye irritation and reflex squeezing of the eyes. The intraocular pressure under these circumstances is unknown but animal and human studies of ocular irritation and forces acting upon the eye indicate a transient increase in intraocular pressure which is not necessarily detrimental to vision.

Secondary contamination of ED personnel from hazardous materials events, 1995-2001.

Hazardous materials (hazmat) events pose a health threat not only for those individuals in the immediate vicinity of the release (ie, members of the general public, on-site first responders, employees), but also for ED personnel (ie, physicians and nurses) treating the chemically contaminated victims arriving at the hospital. Secondary contamination injuries to ED personnel result when exposed victims enter the ED without being properly decontaminated. Data from the Agency for Toxic Substances and Disease Registry's Hazardous Substances Emergency Events Surveillance System were used to conduct a retrospective analysis on hazmat events occurring in 16 states from 1995 through 2001 that involved secondary injury to ED personnel. Six events were identified in which 15 ED personnel were secondarily injured while treating contaminated victims. The predominant injuries sustained were respiratory and eye irritation. Proper victim decontamination procedures, good field-to-hospital communication, and appropriate personal protective equipment (PPE) use can help prevent ED personnel injuries and contamination of the ED.