This is another post in a continuing series on Chemical, Biological, Radiological, Nuclear and Explosive (CBRNE) Threats.
A blood agent is a chemical agent, very toxic to the body, that gets into the blood stream through breathing (inhalation or swallowing (ingestion). They are very fast-acting, lethal poisons (in the proper amount) that can be a gas with a very light smell.
The military chemical blood agent are used as aerosols and as such become effective through breathing in the poison. They are much more effective in confined areas rather than large open areas where the previaling winds and effect or disapte their lethality.
Blood agents are usually Cyanide based compounds that occur in small amounts in the natural environment and in cigarette smoke. They are also prevalent in pesticides and some manufacturing. Cyanide gas is often the cause of death in fires as it is given off when certain materials burn such some plastics and other comon household material such as drapes.
The symptoms that appear from blood agent poisoning depend on the level of concentration and duration of exposure.
Cyanide-based blood agents irritate the eyes and the respiratory tract, while the other less common blood agent, Arsine, is basically non-irritating. The Hydrogen cyanide version has a very faint, bitter, almond type smell. Arsine has a very light garlic like odor that is only detectable at very high levels with wold be lethal.
Exposure to small amounts of cyanide has no effect - remember the cigarette smoke - except for long term exposure and then only linked to degenerative diseaes like cancers. Higher short term exposures at higher concentrations cause dizziness, weakness and possibly nausea, which usually cease when removed from the area.
Long duration - long term exposure can cause permanent brain damage and muscle paralysis. Moderate exposure causes stronger and longer-lasting symptoms, including headaches, sometimes followed by seizures, convulsions then death. Very heavy concentrations will cause severe lethal effects within seconds.
One way to tell if blood agent poisoning has occured on dead people is that their blood will appear very bright.
Cyanide poisoning can be detected by the smell of bitter almonds, or respiratory tract inflammation in the case of cyanogen chloride poisoning although it will be hard in a survival situation to determine this. There is really no way outside of a laboratory to determine arsine gas poisoning, but it may leave a garlic smell on the victim's breath.
At sufficient levels of concentration, blood agents can quickly infuse the blood and cause death in a matter of minutes or seconds. They cause powerful gasping for breath, as the agent denies the body the use of oxygen in the blood. Violent seizure type convulsions and a painful death that can take several minutes. The immediate cause of death is usually respiratory failure.
Detection methods for Chemical agents do exist for hydrogen cyanide in the form of test strips, like the military M8 type paper. Ordinary clothing, particular vinyl rain suits, gloves and protective masks provides some protection, but military grade protective over garments would be recommended. Mask filters containing only charcoal are ineffective, and effective filters are quickly clogged.
Due to their high volatility, cyanide agents generally need no decontamination. In enclosed areas, fire extinguishers spraying sodium carbonate can decontaminate hydrogen cyanide, but the resulting metal salts remain poisonous on contact. Liquid hydrogen cyanide can be flushed with water.
There are some antidotes for Cyanide poisoning but these are mostly beyond the grasp of Urban Survivalists.
Carbon monoxide could technically be called a blood agent because it inhibits the use of oxygen in the blood by contracting with the with the oxygen-carrying hemoglobin.