Zyklon B
Encyclopedia
Trade name
A trade name, also known as a trading name or a business name, is the name which a business trades under for commercial purposes, although its registered, legal name, used for contracts and other formal situations, may be another....
of a cyanide
Cyanide
A cyanide is a chemical compound that contains the cyano group, -C≡N, which consists of a carbon atom triple-bonded to a nitrogen atom. Cyanides most commonly refer to salts of the anion CN−. Most cyanides are highly toxic....
-based pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
infamous for its use by Nazi Germany
Nazi Germany
Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...
to kill human beings in gas chamber
Gas chamber
A gas chamber is an apparatus for killing humans or animals with gas, consisting of a sealed chamber into which a poisonous or asphyxiant gas is introduced. The most commonly used poisonous agent is hydrogen cyanide; carbon dioxide and carbon monoxide have also been used...
s of extermination camps during the Holocaust
The Holocaust
The Holocaust , also known as the Shoah , was the genocide of approximately six million European Jews and millions of others during World War II, a programme of systematic state-sponsored murder by Nazi...
. The "B" designation indicates one of two types of Zyklon. The other was "Zyklon A" – a liquid pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
which released hydrogen cyanide in a chemical reaction with water.
It consisted of hydrogen cyanide (prussic acid, Blausäure in German, hence B), a stabilizer
Stabilizer (chemistry)
In chemistry a stabilizer is a chemical which tends to inhibit the reaction between two or more other chemicals. It can be thought of as the antonym to a catalyst...
, a warning odorant methyl 2-bromoacetate, and one of several adsorbents. Some Zyklon B did not contain the odorant: this has been explained variously, either that it was manufactured specifically for extermination purposes or that this was because of supply shortages.
History
Bayonet
A bayonet is a knife, dagger, sword, or spike-shaped weapon designed to fit in, on, over or underneath the muzzle of a rifle, musket or similar weapon, effectively turning the gun into a spear...
s to combat the advancing Napoleonic army in 1813. During World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
, the French army reportedly – according to Fritz Haber
Fritz Haber
Fritz Haber was a German chemist, who received the Nobel Prize in Chemistry in 1918 for his development for synthesizing ammonia, important for fertilizers and explosives. Haber, along with Max Born, proposed the Born–Haber cycle as a method for evaluating the lattice energy of an ionic solid...
, the German chemist who helped develop poisonous gas for German Army use (see below) – used 2000 tons of prussic acid as a poison gas agent
Chemical warfare
Chemical warfare involves using the toxic properties of chemical substances as weapons. This type of warfare is distinct from Nuclear warfare and Biological warfare, which together make up NBC, the military acronym for Nuclear, Biological, and Chemical...
in artillery
Artillery
Originally applied to any group of infantry primarily armed with projectile weapons, artillery has over time become limited in meaning to refer only to those engines of war that operate by projection of munitions far beyond the range of effect of personal weapons...
ammunition
Ammunition
Ammunition is a generic term derived from the French language la munition which embraced all material used for war , but which in time came to refer specifically to gunpowder and artillery. The collective term for all types of ammunition is munitions...
.
Widespread 'biological' application of hydrocyanic acid was initially limited to the fumigation
Fumigation
Fumigation is a method of pest control that completely fills an area with gaseous pesticides—or fumigants—to suffocate or poison the pests within. It is utilized for control of pests in buildings , soil, grain, and produce, and is also used during processing of goods to be imported or...
of valuable tree crops, namely of citrus fruit, spreading 1887 from California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
to Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
and other countries using liquid prussic acid or calcium cyanide
Calcium cyanide
Calcium cyanide is an inorganic compound with the formula Ca2. It is the calcium salt of hydrogen cyanide. At normal conditions, it appears as colorless crystals or white powder with characteristic odor of bitter almonds . Like other similar cyanides it is very toxic...
or sodium cyanide
Sodium cyanide
Sodium cyanide is an inorganic compound with the formula NaCN. This highly toxic colorless salt is used mainly in gold mining but has other niche applications...
preparations. During World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
other HCN-based pest control applications were developed, and soon fumigation of ships, stores, factories, and even residential buildings with hydrocyanic acid gas became a popular method of combatting insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
and rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
pests in many countries. Thousands of ships, cereal mills and other food processing factories were fumigated with hydrocyanic acid gas until the mid 1930s in Germany alone.
Degussa
Evonik Industries
Evonik Industries is an industrial corporation in Germany owned by RAG Foundation and one of the world´s leading specialty chemicals companies. It was created on 12 September 2007 as a result of restructuring of the mining and technology group RAG...
("Deutsche Gold- und Silber-Scheideanstalt") had a leading role in the German research on pest control with hydrocyanic acid gas from 1916/17 on. Degussa's expertise in handling HCN resulted from its use in the extraction of gold from gold ore. Initially, the so-called pot method was used to simply generate HCN gas by treating sodium cyanide
Sodium cyanide
Sodium cyanide is an inorganic compound with the formula NaCN. This highly toxic colorless salt is used mainly in gold mining but has other niche applications...
or potassium cyanide
Potassium cyanide
Potassium cyanide is an inorganic compound with the formula KCN. This colorless crystalline compound, similar in appearance to sugar, is highly soluble in water. Most KCN is used in gold mining, organic synthesis, and electroplating. Smaller applications include jewelry for chemical gilding and...
with diluted sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
in a pot. The pot method has a number of disadvantages – as has the utilisation of highly concentrated liquid prussic acid. The disadvantages of both methods are prussic acid's limited chemical stability for long-term storage, and the formation of a highly explosive air-HCN mixtures upon application.
In March 1919 Deutsche Gesellschaft für Schädlingsbekämpfung mbH (Degesch
Degesch
The Deutsche Gesellschaft für Schädlingsbekämpfung mbH , in short Degesch, was a German chemical corporation during World War II. Degesch produced pesticides used against weeds and insects...
) was founded by a consortium of German chemical companies including Degussa, and initially led by chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
Nobel laureate Fritz Haber
Fritz Haber
Fritz Haber was a German chemist, who received the Nobel Prize in Chemistry in 1918 for his development for synthesizing ammonia, important for fertilizers and explosives. Haber, along with Max Born, proposed the Born–Haber cycle as a method for evaluating the lattice energy of an ionic solid...
. Haber had World War I experience in the development of poison gas for the German chemical warfare
Chemical warfare
Chemical warfare involves using the toxic properties of chemical substances as weapons. This type of warfare is distinct from Nuclear warfare and Biological warfare, which together make up NBC, the military acronym for Nuclear, Biological, and Chemical...
program. At Degesch, Ferdinand Flury developed Zyklon A in 1920. Its development was a major advance over previous methods of delivering hydrocyanic acid for pest control because of its improved chemical stability and the presence of a warning odorant.
Walter Heerdt, Bruno Tesch
Bruno Tesch (Chemist)
Bruno Emil Tesch was a German chemist and entrepreneur. He was the co-inventor of the insecticide Zyklon B with Gerhard Peters and Walter Heerdt...
and Gerhard Peters were all collaborators of Fritz Haber
Fritz Haber
Fritz Haber was a German chemist, who received the Nobel Prize in Chemistry in 1918 for his development for synthesizing ammonia, important for fertilizers and explosives. Haber, along with Max Born, proposed the Born–Haber cycle as a method for evaluating the lattice energy of an ionic solid...
working at the Kaiser Wilhelm Institute for Physical Chemistry and Electrochemistry
Fritz Haber Institute of the MPG
The Fritz Haber Institute of the Max Planck Society is a science research institute located at the heart of the academic district of Dahlem, in Berlin, Germany....
at Berlin-Dahlem
Dahlem (Berlin)
Dahlem is a locality of the Steglitz-Zehlendorf borough in southwestern Berlin. Until Berlin's 2001 administrative reform it was a part of the former borough of Zehlendorf. Dahlem is one of the most affluent parts of the city and home to the main campus of the Free University of Berlin with the...
. Out of this group of Haber assistants, Walter Heerdt was named the official inventor of Zyklon B in a Degesch
Degesch
The Deutsche Gesellschaft für Schädlingsbekämpfung mbH , in short Degesch, was a German chemical corporation during World War II. Degesch produced pesticides used against weeds and insects...
patent application from 20 June 1922 (number DE 438818). Reichspatentamt awarded the patent on 27 December 1926. The main invention in Zyklon B consisted of the absorption of liquid hydrocyanic acid into a highly porous adsorbent. Initially, heated diatomite (diatomaceous earth
Diatomaceous earth
Diatomaceous earth also known as diatomite or kieselgur/kieselguhr, is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white powder. It has a particle size ranging from less than 1 micrometre to more than 1 millimetre, but typically 10 to...
) was used as an adsorbent. Later, high-porosity gypsum
Gypsum
Gypsum is a very soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is found in alabaster, a decorative stone used in Ancient Egypt. It is the second softest mineral on the Mohs Hardness Scale...
pellets
Pelletizing
Pelletizing is the process of compressing or molding a material into the shape of a pellet. A wide range of different materials are pelletized including chemicals, iron ore, animal compound feed, and more.- Pelletizing of iron ore :...
called Erco-dice (described by eye witnesses as "crystals") as well as disks made from wood fibre
Wood fibre
Wood fibres are usually cellulosic elements that are extracted from trees, straw, bamboo, cotton seed, hemp, sugarcane and other sources.The end paper product dictates the species, or species blend, that is best suited to provide the desirable sheet characteristics, and also dictates the required...
were also used. The adsorbed hydrocyanic acid was very safe in handling and storage when placed in inexpensive airtight cans of various sizes. Gerhard Peters, manager of Degesch, cites M. Kaiser to the effect that
"Heute ist die Zyklon-Blausäure als "das Mittel der Wahl" [...] nicht nur zur Entwanzung und Entlausung, sondern ganz allgemein zur Entwesung großer Räume in allen Erdteilen bekannt. (Today Zyklon-prussic acid is known as the means of choice [...] not only for debugging and delousing but also, in general, for the extermination of large spaces in all quarters of the globe.)
From 1929 onwards the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
used Zyklon B to disinfect the freight trains and clothes of Mexican
Mexican people
Mexican people refers to all persons from Mexico, a multiethnic country in North America, and/or who identify with the Mexican cultural and/or national identity....
immigrants entering the US. Farm Securities Administration photographer Marion Post Wolcott recorded the use of cyanide gas and Zyklon B by the Public Health Service at the New Orleans Quarantine Station during the 1930s.
In early 1942, Zyklon B had emerged as the preferred extermination tool of the Nazi regime for both the Auschwitz-Birkenau and Majdanek
Majdanek
Majdanek was a German Nazi concentration camp on the outskirts of Lublin, Poland, established during the German Nazi occupation of Poland. The camp operated from October 1, 1941 until July 22, 1944, when it was captured nearly intact by the advancing Soviet Red Army...
extermination camps during the Holocaust. The chemical claimed the lives of roughly 1.2 million people in these camps. Rudolf Höss, commandant of Auschwitz, said that the use of Zyklon-B came about on the initiative of one of his subordinates, Captain Frisch, who used the substance to murder some Russian POWs in late August 1941. The experiment was repeated on more Russian POWs, with Hoess watching, in September of the same year. The emergence of Zyklon-B as the preferred chemical was a multi-stranded process.
Production
Degesch (short for "Deutsche Gesellschaft für Schädlingsbekämpfung mbH"; lit. German Limited Company for Pest Control") played a key role in the development (see above) and manufacturing of Zyklon B. Many German companies had stock in Degesch, but all eventually sold their shares to the chemical giant DegussaEvonik Industries
Evonik Industries is an industrial corporation in Germany owned by RAG Foundation and one of the world´s leading specialty chemicals companies. It was created on 12 September 2007 as a result of restructuring of the mining and technology group RAG...
(now part of Evonik Industries) in the early 1920s. To raise capital, Degussa split its controlling interest of Degesch
Degesch
The Deutsche Gesellschaft für Schädlingsbekämpfung mbH , in short Degesch, was a German chemical corporation during World War II. Degesch produced pesticides used against weeds and insects...
with IG Farben
IG Farben
I.G. Farbenindustrie AG was a German chemical industry conglomerate. Its name is taken from Interessen-Gemeinschaft Farbenindustrie AG . The company was formed in 1925 from a number of major companies that had been working together closely since World War I...
in 1930: both companies held a 42.5% share in Degesch, with the remaining 15% held by the Th. Goldschmidt AG of Essen
Essen
- Origin of the name :In German-speaking countries, the name of the city Essen often causes confusion as to its origins, because it is commonly known as the German infinitive of the verb for the act of eating, and/or the German noun for food. Although scholars still dispute the interpretation of...
.
Degesch's role at this point was limited to acquiring patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
s and intellectual property
Intellectual property
Intellectual property is a term referring to a number of distinct types of creations of the mind for which a set of exclusive rights are recognized—and the corresponding fields of law...
: it did not itself produce Zyklon B. The manufacture of Zyklon B was handled by Dessauer Werke für Zucker and Chemische Werke, which acquired the stabilizer from IG Farben, the warning agent from Schering
Schering
Schering AG was a research-centered German pharmaceutical company. It was founded in 1851 by Ernst Christian Friedrich Schering and merged with Bayer's pharma sector in December 2006. The company's headquarters was in Berlin-Wedding, Germany...
AG and the prussic acid from Dessauer Schlempe company and assembled them into the final product. Dessauer Schlempe extracted prussic acid from the waste products of the sugar beet
Sugar beet
Sugar beet, a cultivated plant of Beta vulgaris, is a plant whose tuber contains a high concentration of sucrose. It is grown commercially for sugar production. Sugar beets and other B...
refining process. Apart from Dessauer Werke, Zyklon B was also produced from 1935 in Kaliwerke AG in the Czech town of Kolín
Kolín
Kolín is a town in the Central Bohemian Region of the Czech Republic some east from Prague, lying on the Elbe river.-History:Kolín was founded by king Přemysl Otakar II in the 13th century, first mentioned in 1261. Later on, 1437, a castle was founded here...
and in France.
Upon production, Zyklon B was sold by Degesch to Degussa. To cut costs, Degussa sold the marketing rights of Zyklon B to two intermediaries: the Heerdt and Linger GmbH (Heli) and Tesch & Stabenow
Tesch & Stabenow
The corporation Tesch & Stabenow was a market leader in pest control chemicals between 1924 and 1945 in Germany east of the Elbe....
(Tesch und Stabenow, Internationale Gesellschaft für Schädlingsbekämpfung m.b.H., or Testa) of Hamburg
Hamburg
-History:The first historic name for the city was, according to Claudius Ptolemy's reports, Treva.But the city takes its modern name, Hamburg, from the first permanent building on the site, a castle whose construction was ordered by the Emperor Charlemagne in AD 808...
. Both suppliers split their territory along the Elbe
Elbe
The Elbe is one of the major rivers of Central Europe. It rises in the Krkonoše Mountains of the northwestern Czech Republic before traversing much of Bohemia , then Germany and flowing into the North Sea at Cuxhaven, 110 km northwest of Hamburg...
river, with Heli handling the clients to the west and Testa those to the east.
Zyklon B is still in production in the Czech Republic
Czech Republic
The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....
in the factory Draslovka Kolín a.s. in the city of Kolín
Kolín
Kolín is a town in the Central Bohemian Region of the Czech Republic some east from Prague, lying on the Elbe river.-History:Kolín was founded by king Přemysl Otakar II in the 13th century, first mentioned in 1261. Later on, 1437, a castle was founded here...
, under the tradename Uragan D2, and is sold for the purpose of eradicating insects and small animals. The Czech word uragan means "hurricane" or "cyclone" in English.
Use by Nazi Germany
Zyklon B was used by Nazi GermanyNazi Germany
Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...
to poison prisoners in the gas chamber
Gas chamber
A gas chamber is an apparatus for killing humans or animals with gas, consisting of a sealed chamber into which a poisonous or asphyxiant gas is introduced. The most commonly used poisonous agent is hydrogen cyanide; carbon dioxide and carbon monoxide have also been used...
s of their network of extermination camps throughout Europe. Zyklon B was used at Auschwitz Birkenau
Auschwitz concentration camp
Concentration camp Auschwitz was a network of Nazi concentration and extermination camps built and operated by the Third Reich in Polish areas annexed by Nazi Germany during World War II...
, Majdanek
Majdanek
Majdanek was a German Nazi concentration camp on the outskirts of Lublin, Poland, established during the German Nazi occupation of Poland. The camp operated from October 1, 1941 until July 22, 1944, when it was captured nearly intact by the advancing Soviet Red Army...
and at Sachsenhausen
Sachsenhausen concentration camp
Sachsenhausen or Sachsenhausen-Oranienburg was a Nazi concentration camp in Oranienburg, Germany, used primarily for political prisoners from 1936 to the end of the Third Reich in May, 1945. After World War II, when Oranienburg was in the Soviet Occupation Zone, the structure was used as an NKVD...
. Most of the victims were Jews and the Zyklon B gas became a central symbol of the Holocaust
The Holocaust
The Holocaust , also known as the Shoah , was the genocide of approximately six million European Jews and millions of others during World War II, a programme of systematic state-sponsored murder by Nazi...
. (Zyklon B was also briefly tried out at Bełżec, one of the Operation Reinhard
Operation Reinhard
Operation Reinhard was the code name given to the Nazi plan to murder Polish Jews in the General Government, and marked the most deadly phase of the Holocaust, the use of extermination camps...
camps, but soon dropped in favour of carbon monoxide
Carbon monoxide
Carbon monoxide , also called carbonous oxide, is a colorless, odorless, and tasteless gas that is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal...
from engine exhaust
Exhaust gas
Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel fuel, fuel oil or coal. According to the type of engine, it is discharged into the atmosphere through an exhaust pipe, flue gas stack or propelling nozzle.It often disperses...
as the gassing agent of choice.)
Zyklon B was used in the concentration camps also for delousing to control typhus
Typhus
Epidemic typhus is a form of typhus so named because the disease often causes epidemics following wars and natural disasters...
. The chemical used in the gas chambers was deliberately made without the warning odorant. In quantitative terms, more than 95% of the Zyklon B delivered to Auschwitz was used for delousing and less than 5% in the gas chambers.
In January or February 1940, 250 Gypsy children from Brno
Brno
Brno by population and area is the second largest city in the Czech Republic, the largest Moravian city, and the historical capital city of the Margraviate of Moravia. Brno is the administrative centre of the South Moravian Region where it forms a separate district Brno-City District...
in the Buchenwald concentration camp were used as guinea pigs for testing the Zyklon B gas. On September 3, 1941, around 600 Soviet prisoners of war
Prisoner of war
A prisoner of war or enemy prisoner of war is a person, whether civilian or combatant, who is held in custody by an enemy power during or immediately after an armed conflict...
and 250 sick Polish prisoners were gassed with Zyklon B at Auschwitz camp I; this was the first experiment with the gas at Auschwitz. The experiments lasted more than 20 hours.
According to Rudolf Höss, commandant of Auschwitz, bunker 1 held 800 people, and bunker 2 held 1,200. Once the chamber was full, the doors were screwed shut and solid pellets of Zyklon B were dropped into the chambers through vents in the side walls, releasing the cyanide gas. Those inside died within 20 minutes; the speed of death depended on how close the inmate was standing to a gas vent, according to Höss, who estimated that about one third of the victims died immediately. Johann Kremer
Johann Kremer
Dr Johann Paul Kremer served in the SS in the Auschwitz concentration camp as a physician during World War II, from 30 August 1942 to 18 November 1942....
, an SS doctor who oversaw the gassings, testified that: "Shouting and screaming of the victims could be heard through the opening and it was clear that they fought for their lives." When they were removed, if the chamber had been very congested, as they often were, the victims were found half-squatting, their skin colored pink with red and green spots, some foaming at the mouth or bleeding from the ears.
Post-WW2 legacy
After the war, two directors of Testa – Bruno TeschBruno Tesch (Chemist)
Bruno Emil Tesch was a German chemist and entrepreneur. He was the co-inventor of the insecticide Zyklon B with Gerhard Peters and Walter Heerdt...
and Karl Weinbacher – were tried by a British military court and were executed for their part in supplying the chemical.
The use of the word Zyklon (German for cyclone
Cyclone
In meteorology, a cyclone is an area of closed, circular fluid motion rotating in the same direction as the Earth. This is usually characterized by inward spiraling winds that rotate anticlockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere of the Earth. Most large-scale...
) continues to prompt angry reactions from Jewish groups. In 2002, both Siemens
Siemens
Siemens may refer toSiemens, a German family name carried by generations of telecommunications industrialists, including:* Werner von Siemens , inventor, founder of Siemens AG...
and Umbro
Umbro
Umbro is an English sportswear and football equipment supplier based in Cheadle, Greater Manchester, England. The company is now part of Nike. Umbro designs, sources, and markets sport-related apparel, footwear, and equipment...
withdrew attempts to use or trademark the term for their products.
Holocaust deniers
Holocaust denial
Holocaust denial is the act of denying the genocide of Jews in World War II, usually referred to as the Holocaust. The key claims of Holocaust denial are: the German Nazi government had no official policy or intention of exterminating Jews, Nazi authorities did not use extermination camps and gas...
say that Zyklon B gas was not used in the gas chambers, relying as evidence on the low levels of Prussian blue
Prussian blue
Prussian blue is a dark blue pigment with the idealized formula Fe718. Another name for the color Prussian blue is Berlin blue or, in painting, Parisian blue. Turnbull's blue is the same substance but is made from different reagents....
residue in samples of the gas chambers found by Fred A. Leuchter
Fred A. Leuchter
Frederick A. Leuchter, Jr. is an American Federal Court qualified expert in execution technology and author of forensic Holocaust denial material. He claims to have improved the design of instruments for capital punishment and had execution equipment contracts with several states...
, which Leuchter dismissed as the results of general delousing
Louse
Lice is the common name for over 3,000 species of wingless insects of the order Phthiraptera; three of which are classified as human disease agents...
of buildings. Leuchter's negative control, a sample of gasket
Gasket
thumb|sright|250px|Some seals and gaskets1. [[o-ring]]2. fiber [[Washer |washer]]3. paper gaskets4. [[cylinder head]] [[head gasket|gasket]]...
material taken from a different building in the camp, registered as having no such cyanide residue. The manager of the analytical laboratory
Analytical chemistry
Analytical chemistry is the study of the separation, identification, and quantification of the chemical components of natural and artificial materials. Qualitative analysis gives an indication of the identity of the chemical species in the sample and quantitative analysis determines the amount of...
hired by Leuchter states in an interview in Errol Morris
Errol Morris
Errol Mark Morris is an American director. In 2003, The Guardian put him seventh in its list of the world's 40 best directors. Also in 2003, his film The Fog of War: Eleven Lessons from the Life of Robert S. McNamara won the Academy Award for Best Documentary Feature.-Early life and...
' film Mr. Death: The Rise and Fall of Fred A. Leuchter, Jr.
Mr. Death: The Rise and Fall of Fred A. Leuchter, Jr.
Mr. Death: The Rise and Fall of Fred A. Leuchter, Jr. is a 1999 documentary film by Errol Morris about execution technician Fred A. Leuchter.-Plot:...
, that Leuchter's thick samples of brick would have greatly diluted the cyanide residue, which forms only an extremely fine layer on the walls and cannot penetrate.
In 1994, the Institute for Forensic Research in Kraków
Kraków
Kraków also Krakow, or Cracow , is the second largest and one of the oldest cities in Poland. Situated on the Vistula River in the Lesser Poland region, the city dates back to the 7th century. Kraków has traditionally been one of the leading centres of Polish academic, cultural, and artistic life...
re-examined this claim on the grounds that formation of Prussian blue by exposure of bricks to cyanide is not a highly probable reaction. Using more sophisticated microdiffusion techniques, they tested 22 samples from the gas chambers, delousing chambers (as positive control
Positive control
Positive control may refer to:* Positive control group in scientific control* Positive control, the Air traffic control practice of controlling aircraft whose positions are determined by direct radar observation...
s), and living quarters (as negative controls), finding cyanide residue in both the delousing chambers and the ruins of the gas chambers but none in the ruins of the living quarters.
Mechanism
Zyklon B is a cyanide-based poisonous gas that interferes with cellular respirationCellular respiration
Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate , and then release waste products. The reactions involved in respiration are catabolic reactions that involve...
. Specifically, it prevents the cell from producing ATP
Adenosine triphosphate
Adenosine-5'-triphosphate is a multifunctional nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism...
by binding to one of the proteins involved in the electron transport chain. This protein, cytochrome c oxidase
Cytochrome c oxidase
The enzyme cytochrome c oxidase or Complex IV is a large transmembrane protein complex found in bacteria and the mitochondrion.It is the last enzyme in the respiratory electron transport chain of mitochondria located in the mitochondrial membrane...
, contains several subunits and has ligands containing iron groups. At one of these iron groups, heme a3, the cyanide component of Zyklon B can bind, forming a more stabilized compound through metal-to-ligand pi bonding. As a result of this new iron-cyanide complex, the electrons which would situate themselves on the heme a3 group can no longer do so. Instead, because of the new bond formed between the iron and the cyanide, these electrons would actually destabilize the compound (based on molecular orbital theory); thus, the heme group will no longer accept them. Consequently, electron transport is halted, and the cell can no longer produce the energy needed to synthesize ATP.
External links
- Chemistry is Not the Science – a critique of the arguments of Holocaust deniersHolocaust denialHolocaust denial is the act of denying the genocide of Jews in World War II, usually referred to as the Holocaust. The key claims of Holocaust denial are: the German Nazi government had no official policy or intention of exterminating Jews, Nazi authorities did not use extermination camps and gas...
regarding the use of Zyklon B in gas chambers. - URAGAN D2