Some worry that a chemical used to strip caffeine from coffee beans can increase the risk of cancer. Experts explain if you should be concerned.
Q: I enjoy coffee but dislike how caffeine makes me feel, so I drink decaffeinated coffee. Are there any health risks?
A: Coffeeis a key component of many people’s morning routine.
But having a cup can bring unwelcome effects. One cup of brew can contain between 80 and 100mg of caffeine, which can also cause jitters, anxiety and trouble falling asleep.
“For some people it’s, ‘I want to be able to drink coffee in the afternoon because I really like the taste, but I don’t want to be up all night,’” said Eric Brenner, the assistant director of the Center for Coffee Research and Education at Texas A&M University.
Decaffeinated coffee, generally stripped of at least 97% of its caffeine, is an alternative. But some health advocacy organisations have raised concerns about a chemical used in the decaffeination process because it may raise the risk of some cancers.
Methylene chloride and ethyl acetate are two common chemicals used to decaffeinate coffee beans. Photo / 123RF
There are several ways to make decaffeinated coffee, but two common methods use the chemicals methylene chloride or ethyl acetate to extract and dissolve caffeine from coffee beans.
One method puts coffee beans in direct contact with the chemicals. It begins with steaming green, unroasted coffee beans to make them swell and open their pores, said Tonya Kuhl, the chair of the chemical engineering department at the University of California, Davis.
Then, the beans are rinsed in methylene chloride or ethyl acetate to remove their caffeine, Kuhl said.
The beans are then steamed again and washed to remove residual chemicals, Brenner said, and then they’re roasted.
Are the chemicals used to decaffeinate coffee dangerous?
Experts say no, at least not in the amount you’re exposed to from decaffeinated coffee.
However, people who are exposed to chemicals like methylene chloride at higher levels could have an increased risk of liver and lung cancer and damage to the central nervous system.
In April, the Environmental Protection Agency prohibited most uses of methylene chloride. The chemical can be used to decaffeinate coffee; foods and beverages are primarily regulated by the Food and Drug Administration, which has determined that decaffeinated coffee should not contain more than 0.001% of the chemical.
That means that it would be practically impossible to drink enough decaffeinated coffee to be exposed to dangerous levels of methylene chloride, Kuhl said.
Ethyl acetate, the other chemical used to decaffeinate coffee, also doesn’t warrant much concern, Brenner said. It naturally occurs in kiwi and guava, and is used in products like nail polish and printing ink. But there’s no evidence that it can increase the risk of cancer.
Exposure to ethyl acetate through inhalation, ingestion or skin contact, however, may irritate the eyes, the skin or the throat, according to the Centres for Disease Control and Prevention. Nevertheless, the chemical doesn’t pose a health threat in coffee, experts said.
Once coffee beans are decaffeinated, there may be traces of chemicals left over, Kuhl said. But after the beans are roasted, the chemicals evaporate almost entirely: Coffee beans are typically roasted at temperatures ranging from 180 to 240 degrees Celsius, and methylene chloride and ethyl acetate boil at around 40 and 77 degrees Celsius.
“There’s no health hazard, in my opinion, associated with drinking decaffeinated coffee,” Kuhl said.
The roasting process helps to evaporate any residual chemicals left after decaffeination. Photo / 123rf
If residual chemicals in your coffee still worry you, there are alternatives, Brenner said. Some brands decaffeinate coffee using the Swiss Water Process, which uses water to remove caffeine from coffee beans.
Companies use the process as a selling point because it involves nontoxic ingredients, Brenner said, adding that decaffeinated coffee is “perfectly safe” regardless of how it was made.
To see if coffee beans were decaffeinated this way, look at the bag. It might be stamped with language such as “Water Process,” “Swiss Water decaf” or “Swiss Water decaffeinated”.
Or you can check the brand or company website. “It’s not a big secret,” Brenner said. “All this information is out there.”
