Hydrogen cyanide detoxified

LCt50 Varies widely with concentration because of the rather high rate at which the human body detoxifies hydrogen cyanide. 

The important part of cyanide is the same, whether it is derived from salts, prussic acid, hydrogen cyanide, or released from kernels. It is written by chemists as CN , which means that it is the cyanide ion. When cyanide is absorbed into the body from the stomach, some will exist in this form in the blood and be transported to the liver, where it can be detoxified by an enzyme that converts it into something less toxic, thiocyanate. This is then excreted into the urine. Humans and other animals have probably evolved this mechanism to protect them from the various cyanide-containing plants that occur naturally If the amount taken is too much for the system, the victim suffers poisoning which can be lethal. 

Even the controversial cyanic anticancer substance known as laetrile, or amygda-lin, is thought to be detoxified by a particular enzyme or enzymes in normal cells that is not ordinarily present, or in sufficient concentrations, in cancer cells. The answer is not clear-cut, however, and laetrile remains suspect, if effective at all. More than this, there are certain other food enzymes that may cause laetrile to give off deadly hydrogen cyanide or hydrocyanic acid, or HCN, itself an enzyme inhibitor that acts against bodily processes, notably respiration. (Deadly cyanide, incidentally, is listed as an inhibitor for tyrosinase, the enzyme involved in melanoma.)... 

Over the years, through trial and error, cassava eaters have identified a variety of processes that render the tuber safe. South American native peoples who spat bitter-tasting cassava back into their food bowls and then sampled it again later discovered that the bitterness had vanished. That s because salivary enzymes can also cause linamarin to break down, liberating hydrogen cyanide, which then escapes into the air. In Africa, the traditional method of detoxifying cassava is to pile cassava roots and allow them to ferment in the sun for about seven days. This also releases the enzyme needed to degrade linamarin. 

Diphenylchloroarsine (DA, Clark I) hydrolysis in water will lead to diphenylarsenious acid and hydrochloric acid and diphenylcyanoarsine (DC, Clark II) will lead to hydrogen cyanide and diphenylarsenious oxide. Both acids are toxic, nevertheless they will be detoxified quickly in water. Both arseno-organic compounds from the hydrolysis can later be decomposed into inorganic arsenic compounds, and they will remain toxic. As for all arsenic compounds, the possible bio-accumulation would be a problem of environmental concern. 

Hydrogen q anide can be detoxified rapidly by humans. It is very volatile, and massive amounts of the gas are needed for it to be effective as a CWA. Cyanide is primarily an environmental contaminant of industrial processes. It is used in the metal-processing industry for electroplating, heat treating, and metal polishing, and it can be foxmd in wastewater from many mining operations that use cyanide compoimds in the extraction of metal, such as gold and silver, from ore. 

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