How an ordinary pesticide became the Nazi's most deadly killer in the Holocaust

In the early 1920s, Zyklon B was developed as a solution to the problem of controlling pests, particularly in grain storage and agricultural environments.

German chemists Fritz Haber and Walter Heerdt built upon earlier advancements in cyanide-based fumigation technology.

Its primary function was as a fumigant, which meant that it could be applied in enclosed spaces to eradicate insects, rodents, and other pests.

Grain silos, warehouses, and transportation containers were common environments where the product was deployed to protect food supplies.

Furthermore, it was utilized in controlling lice outbreaks, particularly in areas where sanitation posed significant challenges. 

At its core, the product relied on hydrogen cyanide, a highly toxic gas that was effective in exterminating both insects and rodents.

Chemically, Zyklon B was a hydrogen cyanide-based compound which was formulated for controlled release as a toxic gas.

Hydrogen cyanide, which is known as HCN, is a volatile and flammable substance composed of carbon, hydrogen, and nitrogen.

In order to ensure safer handling during transportation and application, the gas was absorbed onto inert carriers such as diatomaceous earth or gypsum by being absorbed into pellets or discs, which released the lethal fumes when exposed to air and moisture.

As a result, this method made Zyklon B efficient and adaptable to various uses. 

By the mid-1920s, the commercial success of Zyklon B stemmed from its ability to address growing agricultural needs in Europe, where grain supplies were increasingly threatened by infestations.

Meanwhile, industries sought practical solutions to manage pests in large storage facilities and transportation systems.

The product's widespread adoption reflected a demand for technological efficiency during this period of rapid industrialization. 

In the early 1940s, as the Nazi regime escalated its policies of extermination, officials sought methods for killing large numbers of people efficiently and discreetly.

This led to the adaptation of Zyklon B for use in gas chambers within concentration camps.

The compound’s highly lethal hydrogen cyanide properties made it an effective choice for this horrible purpose. 

In 1941, Auschwitz became a central site for testing and implementing this chemical for extermination.

Previously used methods, including mass shootings, were considered inefficient and logistically burdensome.

Zyklon B, which released deadly fumes when exposed to air, was first tested on Soviet prisoners of war in small gas chambers at Auschwitz.

These experiments revealed the compound’s capacity to kill within minutes. 

Soon, camps such as Auschwitz-Birkenau and Majdanek became primary locations for its use, where prisoners were herded into sealed chambers and exposed to the gas released from pellets.

Initially, camp officials experimented with its use in smaller chambers to confirm its effectiveness for mass killing.

By 1942, gas chambers designed specifically for Zyklon B were operational, accommodating thousands of victims in a single day. 

Victims were forced into chambers under the guise of delousing or showering

Once the doors were sealed, SS personnel dropped Zyklon B pellets through openings in the ceiling or walls.

The chemical reaction began almost immediately, producing a lethal concentration of gas within minutes.

It was estimated that 600 kilograms of Zyklon B were delivered monthly to Auschwitz alone during peak operations.

By the end of 1944, over one million people, including Jews, Poles, Romani, and Soviet prisoners of war, had been murdered using this method at Auschwitz-Birkenau 

During the Holocaust, the production and supply of Zyklon B were facilitated by several corporations and individuals who were instrumental in its widespread use.

Degesch, or Deutsche Gesellschaft für Schädlingsbekämpfung, was the primary company responsible for manufacturing and distributing the chemical.

This firm was closely tied to IG Farben, a massive German chemical conglomerate, which controlled a majority share in Degesch.

IG Farben, which was heavily involved in supplying chemicals and materials for the Nazi war effort, oversaw the business operations that ensured Zyklon B reached the concentration camps.

Their executives prioritized profits, disregarding the human cost of their products. 

Under the direction of figures such as Dr. Bruno Tesch, who was a managing director of Degesch, Zyklon B production was scaled up to meet the demands of the SS.

Alongside Tesch, Karl Weinbacher and other corporate leaders played critical roles in the logistics and distribution of Zyklon B, knowing its intended purpose.

These individuals operated within a system that blurred the lines between industrial enterprise and state-sponsored murder. 

Chemists who were part of Degesch’s operations refined the formula to enhance its storage and application.

Meanwhile, company administrators maintained close collaboration with the SS to coordinate deliveries to Auschwitz and other death camps.

In fact, records reveal that Degesch supplied over 20 tons of Zyklon B to camps during the Holocaust. 

By the end of the Holocaust, Zyklon B had directly contributed to the deaths of over one million people in the gas chambers of Auschwitz-Birkenau and other Nazi concentration camps.

This staggering number represented a significant portion of the six million Jewish victims of the genocide, along with tens of thousands of Romani people, Soviet prisoners of war, and others deemed undesirable by the Nazi regime.

Specifically, at Auschwitz alone, approximately 1.1 million individuals were killed, many of whom were murdered in gas chambers designed for the rapid deployment of Zyklon B. 

Survivors who worked in camp operations, such as members of the Sonderkommando, recounted the horrific aftermath as they were forced to remove bodies from the chambers.

Rudolf Höss, the commandant of Auschwitz, described the systematic use of Zyklon B during his trial.

In fact, he admitted that the method allowed for the extermination of thousands of people in a single day, referring to the gas chambers as the most efficient killing system the Nazis employed. 

In the aftermath of World War II, the Nuremberg Trials held individuals and corporations accountable for their roles in the Holocaust.

Beginning in November 1945, these trials brought Nazi leaders and collaborators to justice, focusing on crimes against humanity, war crimes, and genocide.

The International Military Tribunal specifically addressed the involvement of corporate entities like IG Farben.

IG Farben executives, including Fritz ter Meer, were prosecuted for their contributions to the Nazi war machine and their complicity in supplying chemicals used in concentration camps.

Ter Meer received a seven-year prison sentence in 1948 for his involvement. 

The prosecution presented evidence showing that Tesch and Weinbacher had detailed knowledge of the chemical's intended purpose.

In other proceedings, former camp personnel admitted their roles in deploying Zyklon B during extermination operations.

Höss was sentenced to death in 1947 and executed in 1948 near Auschwitz. 

Ultimately, the Holocaust revealed how ordinary tools and substances could be transformed into instruments of mass murder, which is known as a chilling example of industrial and scientific dehumanization.

The ongoing remembrance of Zyklon B reinforces the importance of vigilance in the use of technology and the necessity of ethical accountability, ensuring that such atrocities are neither forgotten nor repeated.