Dry Shampoo Recall: What is Benzene, the Chemical of Concern?

Health Canada on Tuesday launched a massive recall of Unilever hair products containing benzene, a cancer-causing chemical.

This time, the products listed were dry shampoos sold for the past two years by Unilever Bed Head brands TIGI, Dove and Tresemmé. But other hair and skin products have also been subject to recalls in recent years due to the presence of benzene.

More recently, Edgewell Personal Care Company issued a voluntary recall of its Banana Boat scalp and hair sunscreen creams containing benzene in July. In April, the United States Food and Drug Administration issued a recall of several Disney-branded hand sanitizers for the same chemical. Benzene also led to the recall of several Procter & Gamble Company spray antiperspirants in 2021.

Benzene is a petrochemical often found in vehicle emissions. So why do we sometimes end up in dry shampoos, hand sanitizers and aerosol sunscreens, and what are the health risks to consumers?

To better understand, CTVNews.ca takes a look at what benzene is and how it’s used in manufacturing.


Benzene is a clear liquid chemical found in gasoline. It is also used in the synthesis of other chemicals and as a solvent in the chemical and pharmaceutical industries. It is a natural component of crude oil, and is produced by both natural and man-made processes.

Although liquid at room temperature, it evaporates and becomes gaseous very quickly. For this reason, most humans are exposed to it through the air they breathe. It can also be absorbed through skin contact. According to Health Canada, vehicle emissions are the main source of benzene release into the environment, but other sources include cigarette smoke and emissions from volcanoes and forest fires.


Paul Demers spent years of his career studying the effects of harmful chemicals like benzene on human health.

Demers is Director of the Center for Occupational Cancer Research, Senior Scientist at Ontario Health, and Professor in the Division of Occupational and Environmental Health at the University of Toronto’s Dalla Lana School of Public Health.

While exposure to high levels of benzene can cause temporary symptoms such as anemia, memory loss, skin irritation and even unconsciousness, Demers said benzene is also classified as a carcinogen. – a carcinogen.

“It’s not an uncommon thing to come across there,” Demers said in a phone interview with CTVNews.ca on Thursday. “The problem is that we’ve known it’s been a cause of cancer since about 1979 or 1980. So (for) more than 40 years it’s been classified as a human carcinogen internationally.”

Health Canada warns that exposure to benzene can lead to cancers, including leukemia and bone marrow blood cancer, as well as other life-threatening blood disorders.

The agency wrote in its recall notice on Tuesday that the concentration of benzene found in the affected shampoos “is not expected to have any adverse health consequences,” but Demers said there was cause for concern about the effects. cumulative amounts of even trace amounts of benzene found. in personal care products.

“When we think about the low levels in consumer products, we’re really concerned about the long-term effects that might be there, and that’s why cancer appears,” he said. “If it’s personal care products that you’re targeting on your body, whatever’s in them – even if it’s a small amount – we would probably be concerned about that.”


Because benzene is released during combustion and used in heavy industry, the most dangerous exposure to benzene occurs in the workplace. Firefighters and people who work in the printing press, in factories where rubber or steel is processed, or in service stations face some of the highest risks of exposure in the workplace.

To Demers’ knowledge, benzene is not used to produce consumer goods such as dry shampoos and conditioners, aerosol sunscreens, antiperspirants or hand sanitizers. But because it is used to make so many other chemicals and industrial products, there is always a risk of contamination. In the case of Unilever’s October 18 recall, an internal investigation found that the aerosol propellant in the spray cans was the source of contamination.

This is why quality control is such an important part of manufacturing. When benzene appears in a consumer good, Demers said it’s likely because something in the manufacturing or quality control process went wrong.

“It’s a good thing we’re paying attention to consumer products in this way,” he said. “We seem to periodically have toxic metals appearing in products, or different types of chemicals appearing in products, so that’s something we always need to be vigilant about.”

To find out what to do if you think you have purchased a recalled product, visit recalls.canada.ca.