The threat of chemical and biological warfare has been talked about frequently in the past years but the likelihood of such occurrence has assumed serious concern in the emerging terrorism dominated environment. Such tactics have been rightly given the name of Weapons of Mass Destruction (WMD).
Chemical Warfare/Terrorist threat
Chemicals, in the form of poisons, have been used as agents of harm since times immemorial. These assume disastrous proportions when used for large scale or mass killings. Such situations can arise either inadvertently, or through ignorance or in a criminally planned manner. Inadvertent use of poisonous substances – by children in many cases or mixing of toxic chemicals or poisons in country liquor, are well known examples. In times of strife, there are threats of poisoning the water supply of entire town or city and hence special vigilance is to be maintained around water works and water tanks in case of actual or perceived threats of this type.
ii) Toxic Gases
Quick acting, toxic gases have been envisaged as the means of immobilizing or killing large segments of population and are reported to have been manufactured and stored by many countries during wars or war like situations although it is not very clear if these were used as Weapons of Mass Destruction (WMD) so far. The chemicals, in the form of gases, that have been usually talked about in this context are the following:
(a) Nerve Gases are basically highly toxic insecticides and act by inhibiting important enzyme activity in human body. These are generally the compounds of fluorophosphoric acids with alcohol and known as esters. In a well reported case, the Aum Shinri Kyo cult in Japan released Sarin nerve gas in Tokyo subway in 1995. It resulted in the death of 12 persons and many more had to receive medical treatment for extended periods.
(b) Phosgene is the name given to carbonyl chloride and is a poisonous gas used in certain chemical and dyestuff manufacturing processes. It acts on human body by damaging the lungs quickly.
(c) Hydrogen Cyanide interferes with the transfer of oxygen from the blood to the human tissue. This was the killer agent in the Bhopal gas tragedy of 1984 when the Methyl Iso Cyanate gas in contact with the moisture in human eyes, nose and lungs generated hydrogen cyanide which blocked the supply of oxygen to these organs and blinded and killed thousands. That was a chemical accident but a similar scenario of a chemical disaster can be created by a terrorist or enemy agent.
(d) Mustard gas is also called yperite and is chemically identified as dichlorodiethyl sulphide. It has a faint odour of garlic. It causes conjunctivitis in the eyes leading to blindness and creates very painful blisters on the skin.
Release of a poisonous gas at single point or even a multipoint ground based release may affect only the people in the vicinity or the down wind communities. However, aerial spray from low flying vehicles such as helicopters or crop-spraying light aircraft is a more dangerous proposition.
If people can get away quickly or otherwise limit exposure to the poisonous gas and can receive prompt medical attention, chances of survival with manageable injuries will be quite high. But this will depend upon the ability of the medical personnel to correctly identify the toxic gas from the first symptoms on the victims and the availability of antidote medicine in the required quantity.
The All India Institute of Medial Sciences in New Delhi has established the National Poisons Information Centre in its premises to collect and disseminate information about different poisonous substances.
Biological Warfare / Terrorist threat
In the context of biological disasters, mention is often made of botulism, small pox, Venezuelan Equine Encephalitis (VEE) and anthrax; the last one being the one that has recently come into great prominence because determined efforts appear to have been made to use it as a weapon of harming targeted individuals and terrorizing the general public although there has been no evidence of its use as a weapon of mass destruction.
(a) Botulism is perhaps the most lethal biological agent. It is made by a bacterium and spreads through contaminated air, food or water. Death occurs withiir24 hours due to paralysis of breathing muscles. Antibiotic treatment, to be effective, must start before symptoms appear.
(b) Small Pox: Even though small pox as a disease has been eradicated from the world, the virus has been preserved in a few reputed laboratories and is kept under high security. The fear is that if it comes in the hands of a terrorist organization, it may be released through aerosol spray. The problem is that there is no effective drug treatment and vaccination programmes have long been stopped.
(c) Venezuelan Equine Encephalitis (VEE) is fatal among humans and there is no known cure so far. It kills through inflammation of brain tissues. .
(d) Anthrax is caused by the spore forming the bacterium Bacillus Anthracis and is really a disease associated with herbivorous animals. The disease occurs naturally in areas where people raise livestock. Humans contract the disease through cuts in the skin or by breathing in anthrax spores or by eating anthrax-infected meat. If anthrax spores are collected in a concentrated form and spread in the atmosphere on a large scale quietly, as a colorless, odourless and invisible spray, it can certainly turn into a biological disaster because it spreads rapidly when it is inhaled into the lungs. At that stage, it is difficult to control although antibiotic treatment of anthrax is available. The problem here also is that the antibiotic treatment must start before the development of symptoms of fever and cough, otherwise the mortality rate is almost 90%.
Nuclear Warfare/Terrorist Threat:
Even though many countries possess nuclear arsenal, yet on a realistic assessment it is sensible to think that these may never be used as has been seem, for over a half century that such lethal weapons have been in existence. But the possibility always remains of some terrorist organizations making a crude device. Noting the complexities of design and manufacture and the need for a long distance delivery system, the use of a nuclear device by terrorists would perhaps be a remote possibility. Even if it takes place, the incident would not pose problems more complex than those associated with a technological accident in a nuclear power plant, which we have discussed earlier.
A Nuclear Biological and Chemical (NEC) Warfare Directorate has been set up by the Defence Services. An inter-services coordination committee monitors the activities. The Defence Research and Development Establishment (DRDE) of the Defence Research and Development Organization (DRDO) is the premier establishment for studies in toxicology and biochemical pharmacology and development of antibodies against bacterial and viral agents.