This document focuses on the defense against toxin weapons.
Toxins are biological agents that are produced by living organisms: bacteria, plants, or animals. Toxins differ significantly from replicating agents (viruses and bacteria) and from classic chemical agents. The physical characteristics and mechanisms of action of toxins dictate how they must be used as weapons and how they may be defended against. Toxins differ from classical chemical agents by source and physical characteristics. When considering them as biological warfare agents, the physical characteristics of the toxins are much more important than their source. The most important differences are in the areas of volatility and dermal activity. Toxins also differ from bacterial and viral agents in that toxins do not reproduce themselves. Because toxins are not volatile and do not directly affect the skin, an aggressor would have to present toxins to target populations in the form of respirable aerosols. This complicates an aggressor's task by limiting the number of toxins available for an arsenal. The toxicity, ease of production, and stability of toxins are inextricably interconnected. A toxin that cannot be produced in sufficient quantity or is too unstable to survive as an aerosol after delivery cannot be an effective mass casualty biological weapon. However, slightly less toxic toxins that are easy and inexpensive to produce and deliver, and that are stable as aerosols, could be real threats. Some types of toxins are bacterial, marine, fungal, plant, and venom. Effective physical countermeasures to protect against toxins are the protective mask, protective clothing, and decontamination capabilities. Early warning capabilities are being developed to improve battlefield detection systems. Vaccines are available and effective for some of the most important agents, and therapies exist for others. Thorough knowledge of specific threat agents, delivery systems, and national capabilities can assure the effective development and use of physical and medical countermeasures. 5 references