Chewing gum increases risk of cancer — study

TOXIC MICROPLASTICS

Chewing a single piece of gum can result in the release of thousands of toxic microplastics into the human mouth, which may be ingested and pose significant health risks.

Chewing gum releases hundreds of tiny plastic pieces straight into people’s mouths, researchers said yesterday, also warning of the pollution created by the rubber-based sweet. 

According to a study from the University of California in the US, chewing a single piece of gum can result in the release of thousands of toxic microplastics into the human mouth, which may be ingested and pose significant health risks, including cancer and dementia. 

Under the study, Lisa Lowe, a PhD student at the University of California, chewed seven pieces each of 10 brands of gum; then the researchers ran a chemical analysis on her saliva. 

They found that a gramme of gum (0.04 ounces) released an average of 100 microplastic fragments, though some shed more than 600. The average weight of a stick of gum is around 1.5 grammes. 

People who chew around 180 pieces of gum a year could be ingesting roughly 30,000 microplastics, the researchers said. This revelation holds particular significance for Uganda, a nation with a substantial appetite for chewing gum. 

In 2023, Uganda imported five million kilogrammes of chewing gum worth $17.6m (sh62b). 

The majority of these imports, originated from Kenya. Other notable sources included Pakistan, United Arab Emirates and Poland. Understanding the implications of microplastics in chewing gum is crucial for public health awareness in Uganda.

What are microplastics? 

Microplastics are tiny plastic particles, typically less than five millimetres in diameter, resulting from the breakdown of larger plastic materials or manufactured intentionally for specific products. 

They are pervasive in the environment, found in oceans, soil, air and even within the human body. 

Their minuscule size allows them to infiltrate various ecosystems and biological systems, raising concerns about their potential impact on health and the environment.

Health implications of microplastics 

The ingestion of microplastics is an emerging area of concern among health professionals. 

Dr Herbert Nabaasa, the commissioner for environmental health at the health ministry, emphasises the potential risks: “Microplastics can cause inflammation and cellular damage. Their ability to interfere with hormone function is particularly alarming, as this disruption can contribute to chronic diseases over time.” 

Supporting this concern, a study conducted by Italian researchers found microplastics in the arteries of over half of 257 patients examined. This presence was linked to higher risks of strokes, heart attacks, and increased mortality rates. 

Nabaasa acknowledges the need for regulatory intervention: “We will need to involve all the regulators and stakeholders, including UNBS and NDA. Microplastics are undoubtedly a danger to human life. Some studies even suggest that they can cause cancer,” she says. 

Dr Herbert Nabaasa

Dr Richard Lukandwa, a specialist and physician at Rosewell Specialist Hospital in Kampala, highlights another worrying aspect: “Microplastics are not just physical contaminants; they also carry harmful chemicals, including endocrine disruptors and carcinogens. These chemicals can leach into the bloodstream and accumulate over time, increasing the risk of diseases such as cancer, neurological disorders and reproductive issues.” 

Lukandwa notes that potential side effects of microplastics range from mild to severe, depending on the level of exposure and individual susceptibility. 

Once ingested, microplastics can cause digestive problems such as bloating, stomach pain and inflammation in the gut. Studies have shown that microplastics can alter gut microbiota, potentially leading to chronic digestive disorders. 

“These chemicals mimic hormones in the body, potentially leading to reproductive health issues, thyroid dysfunction and metabolic disorders like obesity and diabetes.” 
Research suggests that microplastics can cross the blood-brain barrier, raising concerns about their impact on brain function. Potential risks include cognitive impairment, memory loss and an increased risk of neurodegenerative diseases such as Alzheimer’s and Parkinson’s. 

Some microplastics carry carcinogenic substances that can accumulate in the body over time. 

Long-term exposure has been linked to an increased risk of various cancers, including breast, liver, and colon cancer. 

Dr Grace Mugisha, a public health expert at Makerere University, warns about the cumulative effect of microplastic exposure: “Unlike traditional toxins that can be metabolised and excreted, microplastics persist in the body. The long-term effects are still being studied, but preliminary evidence suggests that chronic exposure could have severe health implications.” 

Lukandwa advises: “Given the potential health risks associated with microplastics in chewing gum, it would be prudent for individuals to limit their consumption and seek alternative methods for freshening breath or managing stress.”

Recommendations 

While the World Health Organisation (WHO) has acknowledged the ubiquity of microplastics in the environment and their presence in the human body, comprehensive assessments of their health impacts are ongoing. 

The WHO emphasises the need for further research to fully understand the implications and to develop appropriate guidelines. 

In Uganda, regulatory bodies may need to consider similar evaluations of food additives and contaminants, including microplastics, to ensure consumer safety. 

Public health campaigns can also play a vital role in educating citizens about potential risks and promoting healthier alternatives.