Chemical agents potential

Great part of the environmental samples is defined as complex mixtures since they are constituted by a diversity of chemical agents potentially dangerous. The evaluation of the pollutants present in complex mixtures is complicated due to the difficulty in recognizing the chemical group harmful to the organisms or the synergistie effect exercised by the present substances. Nonetheless, the evaluation of the complex sample is extremely important since the obtained results are more faithful to the reality of the environmental expositions. 

The use of chemical agents in battie imposes a significant burden on troops because of the cumbersome nature of the protective clothing and the attendant heat load in hot climate situations. This factor alone imposes a burden on potential target personnel, lowering their effectiveness. U.S. troops in the 1991 Mideast war Desert Storm were provided with protective gear that did not deter them with regard to the outcome of the action. 

The next step is the determination of workplace factors that have to be considered in estimating the potential for exposure to chemical agents. This includes all points related to work processes and procedures which may be relevant to exposure, such as... 

More recently, the fact that many of the chemical agents whieh eause the induetion of prophage are carcinogenic has led to the use of lysogenie baeteria in sereening tests for deteeting potential carcinogens. 

The localisation of a particular peptide to a particular brain area and possibly associated with a particular transmitter (e.g. CCK with dopamine in mesolimbic pathways) has often prompted a prediction of function (e.g. CCK may have a role in schizophrenia). Animal studies in which the peptide has been injected into the appropriate brain area or tested on slices taken from the brain area have sometimes been taken to confirm such hypotheses. These approaches have lined up the peptides for a whole range of potential roles, some of which are listed in Table 12.4. Whether these predictions are realities will depend on the availability of chemical agents and their evaluation, not only in animals but also in humans. 

A successful control agent probably should be sought in the marine environment for three reasons. First, this is where the problem is and if a natural control agent has developed, this is where it should be found. Second, the most potent chemical agents seem to be found in the ocean or in the atmosphere potency appears to be required because of the tremendous dilutions. Third, this is where we found what we believe to be a potentially useful control agent. 

Substances with high vapor pressure evaporate rapidly. Those with low vapor pressure evaporate slowly. The impact of vapor pressure on the rate of evaporation makes vapor pressure a very important property in considering the tactical use and duration of effectiveness of chemical agents. A potential chemical agent is valuable for employment when it has a reasonable vapor pressure. One with exceptionally high vapor pressure is of limited use. It vaporizes and dissipates too quickly. Examples are arsine and carbon monoxide. On the other hand, mechanical or thermal means may effectively aerosolize and disseminate solid and liquid agents of very low vapor pressure. Vapor pressure and volatility are related. Translated into volatility, vapor pressure is most understandable and useful. 

Fig. 21.2. Two-microelectrode current-clamp technique used to observe, in single Ascaris body muscle cells in a body-flap preparation, the response to a controlled pulsed application of levamisole. One micropipette, to measure membrane potential, and another micropipette, to inject current, are inserted inside the area of the muscle cell known as the bag region. Levamisole is applied in a time- and pressure-controlled manner from a microcatheter placed over the bag region of the muscle. A second microcatheter is used to apply additional chemical agents (Martin, 1982).

If these methods do prove inconclusive, biomedical sample analysis may provide a unique method for establishing exposure. Due to both the complex technical requirements and the strict forensic approach used it is unlikely that this information will be available in the early phases of response to such an incident. Biomedical sample analysis does however offer another method by which proof of the use of chemical agents can be provided, and thus has a potentially significant role in the overall preparation of a capability for the response to a terrorist chemical agent attack. 

Although not yet a mature science, the development of a practical biomedical sampling capability is underway. At present, the OPCW does not have such a capability, and the capability in Member States in this field is also still very limited. Despite a number of practical and technical challenges, biomedical sample analysis has the potential however to be an extremely sensitive and specific method of establishing credible forensic information on the alleged use of chemical agents. 

Chemical Chemical agents or weapons leave potential and slightly different clues to their use ... 

There is no antidote for nitrogen mustard toxicity, and decontamination of potentially exposed persons must be done within minutes to avoid tissue damage. Victims should be moved out of the hot zone, administered oxygen and/or assisted ventilation, and seek medical attention at once. The nitrogen mustards are delayed chemical agents, and may delay for up to twenty-four hours to show symptoms. They are poisons, and contact with vapor or liquids can be fatal. Do not eat, drink, or smoke during response to a nitrogen mustard incident or criminal event. 

Finding 3. Closure of any chemical agent disposal facility necessitates the identification of potential exposure pathways and environmental receptors in an initial conceptual site model. Closure of JACADS has been complicated because this was not done early and the end use will not be determined until much of the closure planning has been completed. 

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