Chewing gum can release thousands of microplastic particles into saliva

Chewing gum can release hundreds to thousands of microplastic particles into saliva, according to a new study on microplastics and health .

Research presented at the American Chemical Society spring meeting in San Diego, CA, found that, on average, 100 microplastic particles were released per gram of chewing gum.

 

' Our goal is not to make anyone nervous ,' Sanjay Mohanty, PhD, the project's principal investigator and a professor of engineering at the University of California, Los Angeles (UCLA), said in a press statement.

'Scientists don't know whether microplastics are dangerous to us. There are no human trials. But most of us know we are exposed to plastics in our daily lives and that's what the study wanted to look at.

Previous studies have estimated that an individual consumes between 39,000 and 52,000 microplastic particles per year. Microplastics are everywhere and people can be exposed to them through drinks, food, plastic packaging, cutting boards, sponges, product coatings, and manufacturing processes.

Chewing gum is an area that has not been widely researched.

' My lab primarily studies the transport of microplastics in water and soil and their fate in soil. We have looked at the different ways a person can be exposed to microplastics: ingestion and inhalation ,' Mohanty told Healthline.

 

' Most studies on food-related ingestion are about microplastic contamination in food from plastic containers (e.g. plastic water bottles, plastic tea bags), but chewing gum is the only food that contains plastic. However, most people are unaware. The study wanted to measure microplastics in chewing gum. This is important to estimate the total amount of microplastics that are exposed to the human body and any potential negative effects ,' Mohanty continued.

 

Chewing gum and exposure to microplastics

Chewing gum is made of flavorings, sweeteners, rubber base and other ingredients.

In "natural" chewing gum, a plant-derived polymer, such as tree resin, gives the gum its elasticity. A synthetic rubber base made from petroleum-based polymers (resin) is used for synthetic chewing gum.

Researchers tested five synthetic chewing gums along with five commercially available natural chewing gums.

In one part of the experiment, a person chewed seven pieces of gum from each brand to account for different chewing and saliva patterns. The person chewed the gum for four minutes and took saliva samples every 30 seconds. They then rinsed their mouth with clean water. The saliva samples were then combined into one sample.

In another experiment, saliva samples were collected every 20 minutes. The researchers then measured the amount of microplastics in the saliva samples.

The team of researchers initially suspected that synthetic forms of chewing gum would contain more microplastics, but they were surprised to find that natural chewing gum contained similar amounts of microplastics.

' We were not surprised to find microplastics in the chewing gums but were surprised to find them in equal amounts in both synthetic and organic gums. We assumed that organic gums should have less than synthetic gums… We were puzzled about the source of microplastics in them (natural gums) ', said Mohanty.

The impact of microplastics on human health remains a topic of research concern. A 2024 review found that microplastics are suspected of harming human respiratory, digestive, and reproductive health, and may also be linked to colon and lung cancer.

Should I stop chewing gum?

This article points out that both natural and synthetic gums contain similar amounts of microplastics, so in that case it probably doesn't matter much which one you chew. It's best to stop or at least reduce the frequency of chewing gum, especially for children.

The more you chew, the more microplastics you are exposed to. If people want to minimize their exposure to microplastics, which we know are linked to a number of health effects, then not chewing gum would be the best option.