Courtesy: Jeron Tejano/MSU-IIT

MANILA — After previous studies detected microplastics in Laguna de Bay, milkfish, and even drinking water, researchers at the Mindanao State University–Iligan Institute of Technology (MSU-IIT) have raised fresh concerns—this time over the presence of microplastics in road dust.

Their study, published in 2024 in the Philippine Journal of Science, examined the quantity and types of microplastics in road dust, focusing on samples collected in Iligan City.

Jeron Tejano, one of the study’s authors, revealed that polyester made up the majority (58.3 percent) of the microplastics found in road dust. Other identified polymers included ethylene propylene (22.5 percent), ethylene vinyl acetate (8.3 percent), and polyacrylamide (8.3 percent).

Polyester is commonly shed from clothing, while the other microplastics are often linked to tire wear and industrial sources. The findings add to mounting evidence that microplastic pollution is pervasive, with potential implications for both environmental and human health.

How microplastics may affect health

MICROPLASTICS IN URBAN AREAS 

The study examined three sampling stations near Iligan City’s center to represent areas with high human activity and traffic movement.

Researchers collected road dust from designated quadrants, filtering it using the sieving method and a vacuum system in a secured laboratory. The samples were then analyzed under a microscope, with further tests conducted to confirm the type of polymers present.

In Iligan City, researchers found approximately 40 pieces of microplastic per square meter. While this figure may seem concerning, Tejano noted that compared to findings in countries like South Korea and Iran, it remains relatively low.

Courtesy: Jeron Tejano/MSU-IIT

However, Dr. Hernando Bacosa of MSU-IIT revealed in an interview with ABS-CBN News that preliminary data from an ongoing study suggested significantly higher concentrations of microplastics in urban road dust, particularly in Metro Cebu and Metro Manila.

“We found an average of 140 microplastics per square meter in Metro Manila and 105 in Metro Cebu,” Bacosa said.

He added that these findings could help explain previous studies detecting microplastics in air samples, raising concerns about airborne plastic pollution in densely populated areas.

Unlike in Iligan City, where polyester was the dominant polymer, microplastics in Metro Manila were primarily polypropylene and polyvinyl chloride. Polypropylene is commonly used in food containers and packaging, while polyvinyl chloride (PVC) is found in pipes, medical devices, and cable insulation.

HEALTH RISKS 

While researchers acknowledged that more studies were needed to fully understand the long-term health effects of microplastic exposure, they said existing evidence strongly suggested potential risks.

Micro- and nanoplastic particles, being foreign objects, can be ingested or inhaled. This makes them highly capable of carrying and transporting pathogens, chemicals, and even heavy metals into the body.

“May mga evidence that microplastics is associated with some health risk. Kagaya noong pagbubuhol-buhol ng kolesterol, yun pala, mas magiging malaki yung block sa ating mga dugo. Tapos ngayon, sa brain natin, yung sa lungs natin,” Bocosa said.

(There is also evidence that microplastic is associated with some health risk. For instance it can contribute to the build-up of cholesterol leading to blocking of blood flow. It’s now also found in the brain and lungs.)

Courtesy: Jeron Tejano/MSU-IIT

A recent study in the United States further highlighted concerns about microplastic accumulation in human tissues. Researchers found significantly higher concentrations of microplastics in the brains of deceased individuals compared to their livers and kidneys.

Published in Nature, the study found even higher concentrations of micro- and nanoplastics in the brains of patients diagnosed with dementia. 

Study finds microplastics in US brains: Are they dangerous?

“Greater accumulation of MNPs (micro and nanoplastics) was observed in a cohort of decedent brains with documented dementia diagnosis, with notable deposition in cerebrovascular walls and immune cells. These results highlight a critical need to better understand the routes of exposure, uptake and clearance pathways and potential health consequences of plastics in human tissues, particularly in the brain,” the study said. 

URGENT ACTION NEEDED 

Aside from raising awareness of the potential health risks of microplastic exposure, researchers hope their findings will push policymakers to take concrete action.

Despite existing laws like the Ecological Solid Waste Management Act, which mandates local governments to properly manage and dispose of solid waste, and the recently enacted Extended Producer Responsibility (EPR) Act, which holds companies accountable for managing plastic packaging waste, the country’s reliance on single-use plastics—especially in its thriving sachet economy—continues to exacerbate plastic pollution.

Slave to sachets: How poverty worsens plastics crisis in the Philippines

Tejano emphasized that the presence of microplastics in urban road dust also highlights the urgent need for more effective urban planning.

“Urban planners, in the context of roads and highways, should focus on how to manage road cleaning and maintenance. For example having greens along the road would also help and act as filters of microplastic.”

While scientists continue to investigate their long-term health effects, the evidence so far is enough to warrant concern. Addressing the issue requires not just scientific research but also policy reforms, corporate responsibility, and individual action. Without immediate interventions to curb plastic pollution and improve urban planning, microplastics will remain an invisible yet pervasive threat to both the environment and public health.

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