Chemical warfare agents accidental release

Sulfur mustard (SM) is unique among chemical warfare agents because of the large number of reports of its effects in man. The majority of these reports are of its effects after release on the battle field, and give a description of the types of effect and their time course from exposure to resolution of the injury. However, SM is also one of the few chemicals that have been the subject of tests on humans to determine how toxic they are in terms of the doses or dosages that produce toxic effects. Unlike reports of accidental or battlefield exposures, these trials were carried out in chambers under controlled, or at least carefully recorded, conditions, usually with analytical confirmation of chamber concentrations. Many of the reports of these trials, which were elassified at the time they were produced, have now been released into the public record and are available for scientific review. This chapter reviews those reports that are now available to the general public in addition to the work already published. Volunteer trials were carried out in the USA, UK, India and Australia. The reports of these trials that have been released to the public record are held by the Defense Technical Information Service... 

Since the appearance of the first edition, toxic trauma from deliberate exposure to chemical warfare agents has continued in the Syrian Civil War, causing many thousands of casualties. The fear of further use of chemical weapons by terrorist organisations continues, and thus readiness to deal with chemical casualties in the urban civil setting remains more important than ever. In industrial and domestic settings, the accidental release of toxic chemicals continues and no hospital department can afford not to prepare for such incidents, both in daily practice and as part of disaster-response planning. The hazards of toxic trauma remain therefore as real as ever, and I hope that the new edition of this book will help to inform and to prepare responses accordingly. 

Industry provides a major source of many of the chemicals discussed in this chapter. Industrial chemicals are legitimate articles of commerce which are traded in very large volumes and are not subjected to the same regulations or export controls as chemical warfare agents. Widespread exposure may therefore occur from accidental or intentional release of such chemicals due to a fire, explosion or sabotage. Awareness of these sources is essential when attempting to establish the causative agent. 

There are clear ethical constraints that prevent human research that could definitively answer the questions of concern regarding the military operational and civilian health risks of exposure to low-levels of chemical warfare nerve agents. Only three sources of relevant human data are available for analysis. These data are from either past human volunteer studies, reports based on accidental exposures, or reports of the consequences of malicious releases of the agents. While these sources are valuable, the data have some limitations for deriving dose-response relationships because of inferior analytical and clinical methods or the lack of precise estimates of exposure. 

Although chemical and biological agents are usually linked together as potential hazards, there are substantial differences between the effects of chemical substances and bacteria or viruses and the casualties caused. Chemical warfare is the deliberate equivalent of the accidental release of chemical substances. In the civil context this is termed hazardous materials release (HAZMAT) (Anon, 1995 Borak et al, 1991 Bronstein and Currance, 1994 Moles, 1999 Organization of Economic Co-operation and Development, 1994) (Table 1 and Figure 1). 

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