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Risk of secondary cancer from chemotherapy is low; chemo ingredients aren’t just 100% mustard gas

Chemotherapy is 100% mustard gas, chemotherapy causes cancer
Accurate: Chemotherapy drugs are highly toxic and target fast-dividing cells of all types—both healthy and cancerous. This cell destruction results in the negative side effects associated with chemotherapy treatment.
Factually inaccurate: There are over 100 different types of chemotherapy drugs, all of which are made from different ingredients. Not all chemotherapy drugs are derived from nitrogen mustard (mustard gas).
Misleading: Second primary cancers are sometimes linked to chemotherapy, but the risk of developing these cancers is, on the whole, low. The risks of leaving a primary cancer untreated, on the other hand, are high, including metastasis (spreading) of the primary cancer and death.
Cancer cells replicate quickly, which can lead to the growth of malignant tumors. Chemotherapy is used to halt the spread of cancerous cells, but because chemotherapy drugs are indiscriminate, they can also damage healthy cells. This can lead to side effects including fatigue, hair loss, and gastrointestinal issues. However, the net benefit of chemotherapy in eliminating cancer cells often outweighs these difficult side effects.

FULL CLAIM: “Chemotherapy did kill the cancer; yes, the chemotherapy did shrink the tumor; but the chemotherapy is 100% mustard gas. Mustard gas is literally 100% acidic. So not only did it kill the cancerous cells, but it killed every good cell in the body too. So chemotherapy naturally causes cancer”


Cancer occurs when abnormal cells multiply uncontrollably in the body. However, cancer isn’t a single disease but rather a group of diseases, each with its own causes and risk factors. More than 200 types of cancer exist, and doctors use different courses of treatment depending on the type and aggressiveness of the cancer diagnosed. These treatments include surgery, radiation, and different types of therapies, including chemotherapy.

Posts shared on Facebook and TikTok in late May 2024 claimed that chemotherapy consists of “100% mustard gas” and that it “naturally causes cancer”. The posts rehashed content from a December 2023 interview with Alexander Hickman, an herbalist who also goes by the name Yahki Rapha Elohim. The interview was shared on a YouTube channel called “I Never Knew Tv”, and at the time of publishing had received over 363,000 views.

Hickman himself has more than 871,000 followers on Instagram. He sells herbal compounds and formulas through his store Yah’Ki Awakened LLC, which he claims have cured “Diabetes, Herpes, Sickle Cell Anemia, various Cancers, Autoimmune Diseases, and many more”.

As we will explain below, the claims about chemotherapy misrepresent the ingredient profiles of current chemotherapy drugs on the market. They also ignore the harm that occurs when cancer is left untreated.

How chemotherapy drugs work

Cells in the human body are constantly dividing to assist with the growth, maintenance, and repair of cells and tissues. This process is called the cell cycle (or cell-division cycle).

Chemotherapy uses drugs that target fast-dividing cells. Chemotherapy drugs are one approach to treating cancer since cancer arises due to unregulated cell division. However, chemotherapy drugs can’t distinguish between healthy cells and cancerous cells. Their indiscriminate toxicity means they also kill off fast-dividing healthy cells, such as those that contribute to hair growth. This can lead to side effects including hair loss, easy bruising and bleeding, and gastrointestinal issues, among others.

The claim that “not only [did chemotherapy] kill the cancerous cells, but it killed every good cell in the body too” thus contains a grain of truth, insofar that chemotherapy can kill off some “good” (or healthy) cells.

The history of chemotherapy and mustard gas

The connection between chemotherapy and mustard gas crystallized during World War II. After the bombing of a port in Bari, Italy, thousands of soldiers were exposed to water and air contaminated with mustard gas, a human-made chemical warfare agent. In the days following the bombing, some soldiers developed severe chemical burns and others who showed relatively few symptoms died.

A chemical warfare expert was sent to the scene of the Bari bombing to analyze these puzzling casualties. He discovered that exposure to mustard gas suppressed the production of new white blood cells. His report, in combination with an experimental clinical trial led by Yale researchers, led to the discovery that concentrated doses of nitrogen mustard, a derivative of mustard gas, could reduce tumors in patients with lymphosarcoma (non-Hodgkin’s lymphoma).

This paved the way for Mustargen (mechlorethamine), the first FDA-approved chemotherapy drug, to be released in 1949. Today, there are more than 100 types of chemotherapy drugs that are composed of different ingredients—not just nitrogen mustard. According to the American Cancer Society:

“[Chemotherapy] drugs are very different in their chemical composition (what they are made of), how they are prescribed and given, how useful they are in treating certain types of cancer, and the side effects they might have.”

Thus, to say “chemotherapy is 100% mustard gas” is incorrect.

Can chemotherapy cause second cancers?

As we established, the claim’s implication that chemotherapy drugs are highly toxic is accurate. But the claim that “chemotherapy naturally causes cancer” is misleading.

While the reel presented no additional information or evidence for this part of the claim, it may refer to second primary cancer. The U.S. National Cancer Institute (NCI) defines second primary cancer as one which “may occur months or years after the original (primary) cancer was diagnosed and treated”.

Some studies have found that chemotherapy may increase the risk of second primary cancer[1,2]. More specifically, according to the NCI, alkylating agents in chemotherapy drugs can “interfere[sic] with the cell’s DNA and inhibit[sic] cancer cell growth”. This in turn can lead to mutations in the DNA that may increase the risk of cancer.

The American Cancer Society specifies that “[t]he cancers most often linked to chemo are myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML)” and that “the risk [of secondary cancer] gets higher with higher drug doses, longer treatment time, and higher dose-intensity (more drug given over a short period of time).”

Yet the likelihood of these secondary cancers developing in response to chemotherapy is relatively rare. In an interview with the University of Texas’ MD Anderson Cancer Center, clinician J. Andrew Livingston said “the chance of developing a chemotherapy-induced leukemia […] is probably less than 1%”. Pediatric oncologist Sajad Khazal agreed, saying “[a]mong children and young adults, the odds are very low. I’d say less than 2% of all pediatric and young adult patients will develop a secondary cancer”.

Risks associated with cancer outweigh the risk of developing second cancers

Cancer is a leading cause of death worldwide. One of the risks associated with leaving cancer untreated is metastasis—the spreading of cancer cells from one part of the body to another. To prevent this from occurring, chemotherapy is sometimes the only effective form of treatment, particularly when a patient’s primary cancer hasn’t responded to other treatments.

It’s also worth noting that although side effects from chemotherapy can be unpleasant, they can also differ depending on the person, chemotherapy drug, and dose. Not everyone will suffer from side effects of chemotherapy drugs, and for those who do, there are resources that exist which provide guidance on how to manage these symptoms.

While the claim implies that avoiding chemotherapy allows a person to avoid the risk of a hypothetical second primary cancer, it’s important to keep in mind that untreated cancer is, by and large, fatal. Chemotherapy, on the other hand, offers people with cancer a greater chance of survival. On balance, the benefits of chemotherapy outweigh their risks.



Published on: 08 Jun 2024 | Editor:

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