Editing Blood agent (section)

== Symptoms ==

The symptoms of blood agent poisoning depend on concentration and duration.

Cyanide-based blood agents irritate the eyes and the [[respiratory tract]], while arsine is nonirritating.<ref name="Walsh 151" /> [[Hydrogen cyanide]] has a faint, bitter, almond odor that only about half of all people can smell. Arsine has a very faint garlic odor detectable only at greater than fatal concentrations.<ref name="Walsh 150" />

Exposure to small amounts of cyanide has no effect.<ref name="Walsh 151" /> Higher concentrations cause dizziness, weakness and nausea, which cease with the exposure, but long-time exposure can cause mild symptoms followed by permanent brain damage and muscle paralysis.<ref name="Walsh 151" /> Moderate exposure causes stronger and longer-lasting symptoms, including headache, that can be followed by convulsions and coma. Stronger or longer exposure will also lead to convulsions and coma. Very strong exposure causes severe toxic effects within seconds, and rapid death.<ref name="Walsh 151" />

The blood of people killed by blood agents is bright red, because the agents inhibit the use of the oxygen in it by the body's cells.<ref name="Walsh 151" /> Cyanide poisoning can be detected by the presence of [[thiocyanate]] or cyanide in the blood, a smell of [[bitter almond]]s, or respiratory tract inflammations and congestions in the case of [[cyanogen chloride]] poisoning.<ref name="Walsh 151" /> There is no specific test for arsine poisoning, but it may leave a garlic smell on the victim's breath.<ref name="Walsh 151" />