Stay informed with a weekly digest focused on enhancing your well-being. Sign up for CNN’s Life, But Better newsletter for practical tips and insights.Are you considering all the ways microplastics are infiltrating your daily routine? Chewing gum might be a surprising source, as suggested by a recent pilot study revealing that chewing just one piece can release hundreds to thousands of microplastics into saliva.This study, currently undergoing peer review, is set to be presented at the biannual meeting of the American Chemical Society in San Diego. Once the review is finalized, the authors anticipate the report will be published in the Journal of Hazardous Materials Letters later this year.“Our intention is not to cause alarm,” explained Dr. Sanjay Mohanty, senior study author and associate professor at the Samueli School of Engineering at the University of California, Los Angeles. “There’s uncertainty about the safety of microplastics. Without human trials, scientists cannot confirm their impact. But given our regular exposure to plastics, we wanted to investigate further.”Microplastics are tiny polymer fragments ranging from less than 0.2 inch (5 millimeters) to 1/25,000th of an inch (1 micrometer) in size. Anything smaller is classified as nanoplastics, measured in billionths of a meter. Polymers consist of long chains of repeating molecular units known for their strength and flexibility. While synthetic polymers are common in plastics, natural polymers like plant-derived cellulose are also used for texture, elasticity, and flavor retention in chewing gum, according to the authors.Past studies have shown that microplastics can enter the body through ingestion and inhalation, with traces found in various body parts and fluids such as blood, lungs, placenta, brain, and testicles. This led the researchers to explore potential sources of microplastic ingestion and their concentrations.“Chewing gum was selected because it’s the only food item containing plastic polymers as an ingredient,” Mohanty noted. “Other foods may have microplastics due to processing and packaging methods.”The researchers examined 10 popular chewing gums in the US, half of which were synthetic and the other half natural. Since gum labels rarely disclose their ingredients or production methods, the researchers couldn’t trace how microplastics ended up in the tested gums, leaving consumers unaware of the gum’s complete composition.During the study, a participant would chew a gum for four minutes while researchers collected saliva every 30 seconds in a centrifuge tube. The participant then rinsed their mouth multiple times with purified water, and the researchers combined this rinse with the saliva sample.
To ensure thorough capture of all microplastics in the mouth, the researchers repeated the process seven times for each gum variant. Some gums were chewed for a total of 20 minutes, with saliva samples collected every two minutes to observe how the release of microplastics correlated with chewing duration. Various filtering and chemical analysis methods, such as microscopy, were employed by the authors to identify the types and quantities of microplastics present in the gums. By deducting the initial rinse sample’s microplastics from those found in the chewing gum saliva samples, the research team accurately estimated the microplastics released during gum chewing.
The analysis revealed that on average, just 1 gram of chewing gum released around 100 microplastics, with certain gums releasing up to 637 microplastics per gram. The weight of a typical stick of gum could range from 1 gram to several grams based on different sources. Notably, 94% of microplastics were shed within the first eight minutes of chewing.
Surprisingly, the study found that natural gums did not significantly differ from synthetic gums in microplastic release. The average microplastics content in 1 gram of synthetic gum was 104, while natural gum contained 96 microplastics. Both types primarily emitted four types of synthetic polymers: polyolefins, polyterephthalates, polyacrylamides, and polystyrenes, commonly used in everyday plastic products.
Dr. Tasha Stoiber, a senior scientist at the Environmental Working Group, highlighted that the release of microplastics from chewing gum was expected due to plastic’s behavior under stress. Dr. David Jones, a teaching fellow at the University of Portsmouth, emphasized that the study provided essential data for further research on microplastics.
The National Confectioners Association assured the safety of chewing gum, emphasizing the priority of food safety for U.S. confectionery companies. However, uncertainties remain regarding gum microplastics. The study’s analysis tools were limited to identifying particles larger than 20 micrometers, potentially underestimating the presence of smaller microplastics and nanoplastics. The discovery of synthetic polymers in natural gums raised questions, possibly linked to their use in food packaging.
The research sheds light on the prevalence of microplastics in chewing gums and serves as a foundation for future investigations into this environmental issue.
Dr. Oliver Jones, a chemistry professor at RMIT University in Australia, highlighted the importance of considering lab contaminants or measurement errors when analyzing studies, as stated by the Science Media Centre. Not directly involved in the research, Jones pointed out the challenges in determining the source of microplastics in natural chewing gums due to limited disclosure of gum compositions. Additionally, Dr. David Jones from the University of Portsmouth noted the presence of uncommon polymers like polyterephthalates in synthetic gums, urging for a precautionary approach towards potential health impacts. Despite regulatory agencies downplaying concerns about microplastics in food and water, experts advocate for proactive research to understand and address any health implications. The study also sheds light on the environmental pollution caused by improper disposal of chewing gum. Stay updated with more news and newsletters by signing up at CNN.com.
