WHO Agency Lists Talc, Acrylonitrile as Carcinogenic

Researchers found evidence of ovarian cancer from exposure to talc which is used in deodorants and body powder.

The logo of the World Health Organization at the WHO headquarters in Geneva on Oct. 24, 2017. Fabrice Coffrini/AFP via Getty Images

The International Agency for Research on Cancer (IARC), the cancer agency of the World Health Organization (WHO), classified two common substances used in products such as clothing and cosmetics as carcinogenic.

The article, published in The Lancet on July 5, summarized the findings made by a group of 29 scientists who investigated the carcinogenic potential of acrylonitrile and talc.

People are typically exposed to the organic compound acrylonitrile through inhalation of smoke from cigarettes, the article states. One cigarette is estimated to contain between 3.2 and 15 mg of acrylonitrile. People can also be exposed by polluted air. Acrylonitrile can cause in headaches, weakness, nausea, vomiting, shortness of breath, and even death, according to the article.

The scientists classified acrylonitrile as Group 1 “carcinogenic to humans on the basis of sufficient evidence for cancer in humans for lung cancer.”

“There was also limited evidence in humans for bladder cancer. The evidence was mainly from studies in workers producing or using acrylonitrile,” said a July 5 IARC press release. “In addition, there was sufficient evidence for cancer in experimental animals.”

Group 1 is the highest level of certainty that a substance can cause cancer.

One study reviewed by researchers looked at workers from different industries using or producing acrylonitrile and found that higher exposure was linked to higher rates of lung cancer mortality.

Talc is used in pottery, rubber, and pulp and paper industries while acrylonitrile is used for making polymers in clothing, carpets, automotive parts, and consumer products.

Talc is a naturally occurring mineral used in cosmetics such as body powders and deodorants. Human exposure via these items is well documented, IARC noted. People can get exposed to talc via drugs and food, although documentation of cases remains scarce.

The scientists classified talc under Group 2A, or “probably carcinogenic to humans.” The researchers found “limited evidence for cancer in humans (for ovarian cancer).”

They discovered “sufficient evidence” of cancer among experimental animals. There was “strong mechanistic evidence” that talc exhibits certain carcinogenic characteristics.

The researchers came from multiple nations, including the United States, Australia, China, Canada, Italy, and Spain. None of them reported any competing interests.

Risks of Carcinogenic Items

The IARC says it aims to promote international collaboration in cancer research. The WHO agency is working on a global cancer biobank that has roughly six million biological samples from around 600,000 individuals. The samples are expected to help in the cancer investigations.

Last year, IARC classified artificial sweetener aspartame as being “possibly carcinogenic to humans.” Researchers found “limited evidence” showing a potential link between aspartame and liver cancer. Aspartame was given Group 2B classification.

At the time, Francesco Branca, the WHO’s nutrition and food safety director, said that the agency was neither asking companies to withdraw aspartame products nor recommending people to stop consuming it. “We’re just advising for a bit of moderation.”

Knowing about carcinogenic substances is crucial as it can lead to better cancer prevention and mitigation strategies.

The American Cancer Society (ACS) estimates that about two million new cancer cases (excluding skin cancer and noninvasive cancers) will be diagnosed this year in the United States. Roughly 611,720 deaths are expected, which is around 1,680 deaths per day.

Cancer is the second most common cause of death in the United States, after heart disease.

In March, the U.S. Environmental Protection Agency (EPA) announced plans to curtail the emission of a chemical called ethylene oxide that is known to cause cancer.

Ethylene oxide is used in many products such as textiles, medicines, adhesives, and detergents. It is also used to sanitize medical and surgical equipment that cannot be sterilized by steam.

The agency’s rules require sterilization facilities to cut down ethylene oxide emissions. This is expected to “reduce lifetime cancer risks” for people who live near such facilities, the agency said.

Meanwhile, counterfeit products from China could pose major carcinogenic risks. A recent investigation from the South Korean government found that many of these Chinese products contained dangerously high levels of carcinogenic heavy metals. These include goods such as clothing, shoes, and bags.

Between Nov. 6 and Dec. 1, 2023, South Korea confiscated almost 143,000 counterfeit items from China. An analysis of 83 types of skin-contact products such as leather bags and earrings found that 30 percent of them contained excessive levels of cadmium and lead. In some products, the levels reached up to 930 times the allowable limit.