Advancing In-Depth Research on Microplastic Pollution

Microplastics Found in the Human Body
Scientists have reported that Earth has accumulated 8.3 billion metric tons of plastic waste, of which only 9% is recycled, 12% is incinerated, and 79% ends up in landfills or the environment. By 2050, it is estimated that about 12 billion metric tons of plastic waste will be dumped in landfills or the natural environment.

According to UNEP, the countries with the highest levels of mismanaged plastic waste discharged into water bodies include: China (8.8 million tons/year), Indonesia (3.2 million tons/year), and the Philippines (1.9 million tons/year). Vietnam ranks fourth, with over 1.8 million tons of plastic waste discharged annually, of which only 27% is recycled. This alarming reality calls for urgent research into plastic waste treatment technologies and fundamental studies on microplastics.

The scientific article "Microplastics in the marine environment" (https://doi.org/10.1016/j.marpolbul.2011.05.030) reported the first findings of marine plastic debris in the early 1970s. Over the following decades, the scientific community has increasingly pushed for in-depth research on microplastics.

Microplastics originate from industrial processes, consumer products, and waste management activities. They are essentially tiny fragments of plastic waste, typically measuring only a few micrometers or even nanometers. In marine environments, microplastics often float due to their low density, dispersing across large surface areas. Some particles sink to the seafloor, increasing in concentration and becoming habitats for marine organisms. Microplastics are found everywhere—even on Mount Everest, in Antarctica, and in the Mariana Trench, the deepest part of the ocean.

In the article “Discovery and quantification of plastic particle pollution in human blood” (https://doi.org/10.1016/j.envint.2022.107199), researchers collected blood samples from 22 healthy volunteers. Using double pyrolysis gas chromatography/mass spectrometry, they measured plastic particles ≥700 nm in size. For the first time, four widely produced plastic polymers—polyethylene terephthalate (PET), polyethylene (PE), styrene polymers (including polystyrene, expanded polystyrene, acrylonitrile butadiene styrene), and methyl methacrylate (PMMA)—were identified and quantified in human blood. Polypropylene (PP) was also tested but found at levels below the detection threshold. In this small-scale study, the average quantifiable concentration of microplastics in human blood was 1.6 µg/ml, marking the first time polymer mass was measured in human blood. This pioneering human biomonitoring study confirms that plastic particles can be absorbed and circulate in the bloodstream.

How do microplastics enter our bodies? On average, 4,885 microplastic particles are detected per square meter of air daily. Bottled water is one of the highest sources, containing about 100 particles per liter. Microplastics are also commonly found in foods such as meat, shrimp, oysters, sugar, commercial rice, sea salt, breast milk, infant formula, honey, and beer. Through eating and breathing, people may ingest up to 5 grams of microplastics per week—roughly the equivalent weight of a credit card.

Driving Deep Research into Microplastic Pollution

The alarming volume of plastic waste in Vietnam serves as a clear research indicator for environmental scientists. With over 2,000 rivers longer than 10 km, 112 river mouths, and more than 3,260 km of coastline, Vietnam's dense hydrological network also acts as a conduit for transporting microplastics from land to ocean.

Since 2018, Vietnamese scientists, in collaboration with French experts led by Dr. Emilie Strady (from the French Research Institute for Development), have conducted a foundational assessment of microplastic concentrations in the marine and freshwater environments of a developing Southeast Asian country, including Vietnam.

An adaptable method was developed to enable local researchers to monitor microplastics in sediments and surface water at 21 sampling sites (rivers, lakes, bays, beaches) across eight provinces and cities from north to south. Surface water microplastic concentrations ranged from 0.35 to 2,522 particles/m³, with the lowest levels recorded in bays and the highest in rivers. A cubic meter of water in the To Lich River contained up to 2,522 microplastic particles—the highest among all surveyed rivers. This concentration dropped to 93.7 particles/m³ in the Nhue River. In the Dong Nai River system, concentrations were 3.9 particles/m³; Han River, 2.7 particles/m³; and Red River, 2.3 particles/m³. At estuaries and bays studied by Dr. Strady’s team, levels ranged from 0.4 particles/m³ in Cua Luc Bay (Quang Ninh) to 28.4 particles/m³ at Dinh River estuary (Ninh Thuan). In most environments, microplastic fibers dominated over fragments, comprising 47% to 97% of total particles.

At VAST, scientists have focused on microplastic pollution and produced outstanding research. The study “Microplastics in sediments from urban and suburban rivers: Influence of sediment properties”, led by Assoc. Prof. Dr. Duong Thi Thuy and colleagues at the Institute of Energy and Environmental Science and Technology, was published in Science of the Total Environment, a leading multidisciplinary journal (ISI-indexed, Q1 ranking). The research examined microplastic presence in riverbank sediments from 12 sites across urbanized and less developed rivers (To Lich, Nhue, and Day) in the Red River Delta, during both dry and rainy seasons. Microplastic concentrations ranged from 1,600 to 94,300 particles per kilogram of dry weight (kg⁻¹ dw). Fibers were the dominant form, with polypropylene (PP) and polyethylene (PE) as the primary polymers. This work was recognized as an outstanding publication by VAST in 2023.

In 2024, the article “Evaluation of microplastic bioaccumulation capacity of mussel (Perna viridis) and surrounding environment in the North coast of Vietnam”, authored by Assoc. Prof. Dr. Do Van Manh, Prof. Dr. Trinh Van Tuyen, PhD candidate Le Xuan Thanh Thao, and MSc. Nguyen Duy Thanh, was published in Marine Pollution Bulletin (SCIE, Q1). The study successfully investigated microplastic contamination in green mussels (Perna viridis) and the surrounding coastal environment (seawater and sediments) in northern Vietnam. Average microplastic concentrations were 3.67 ± 1.20 particles/g wet weight and 25.05 ± 5.36 particles/individual in mussels; 88.00 ± 30.88 particles/L in surface seawater; and 4,800 ± 1,776 particles/kg dry weight in beach sediments. Microplastic fragments comprised 69.86% to 82.41% and were the dominant shape. Most particles measured 1–150 µm in size. Polyethylene terephthalate (PET) was the most prevalent polymer across all samples. Risk assessment (Level II ~ III) based on chemical composition flagged warnings at several sites. The results provide a reference for further research on plastic pollution, particularly in organisms and their potential health effects on humans in Vietnam.

Sampling site map

Microplastic concentrations in water and sediment

Microplastic polymer risk index in mussels and habitat

According to Assoc. Prof. Dr. Mai Huong from the University of Science and Technology of Hanoi, one of the greatest challenges in studying microplastics is sample collection in the field. Planning sampling campaigns requires scientists to be hands-on and adaptive in rivers, lakes, and canals. “At offshore locations, large waves sometimes prevent sample collection, forcing us to return to shore and wait for calmer weather or change locations,” she noted. “In fieldwork, male researchers often have advantages in physical strength and field skills.”

Working with French experts and researchers from Vietnamese universities and institutes on microplastic studies in Vietnam and Southeast Asia, Dr. Mai Huong’s team published a paper in Marine Pollution Bulletin that has since been cited 157 times—demonstrating international research interest in Vietnam’s microplastic studies. Her team also completed studies on microplastics in Hanoi’s lakes and their impact on bottom-dwelling macrofauna. Results showed that Hanoi’s urban lakes had relatively high microplastic concentrations compared to urban lakes worldwide. In areas with higher microplastic levels, diversity and density of macrofauna also varied. These findings have been published in reputable international and national journals.

Microplastics are becoming a major threat to the environment and human health. These particles persist in the environment, polluting soil, water, and air, and accumulate through the food chain, affecting ecosystems and living organisms—particularly marine life.

According to scientists, the toxicity of microplastics stems from both mechanical and chemical factors. Microplastics can physically harm marine organisms by blocking digestive tracts. They also contain additives (plasticizers, flame retardants, antioxidants, etc.) and can absorb environmental pollutants like heavy metals, organic pollutants, and pathogens. When ingested, these toxins can be released into organisms, causing poisoning, endocrine disruption, and bioaccumulation, ultimately affecting human health.

One challenge in Vietnam’s microplastic research is the lack of quantitative data. Most studies are still at the qualitative level—identifying presence but not concentrations—making it difficult to assess human health and ecological risks.

Experts also call for expanded survey scopes, moving beyond localized studies to broader investigations from land to ocean, including interconnected samples such as water, sediment, and organisms.

Moreover, international collaboration is vital to enhance research capacity and explore microplastic pollution in Vietnam’s marine ecosystems—especially sensitive areas like coral reefs, estuaries, and nature reserves.

Assoc. Prof. Dr. Do Van Manh, Director of the Institute of Energy and Environmental Science and Technology (VAST), stated: “Microplastics are an emerging pollutant that is very difficult to remove from the environment or living organisms. Current technologies offer only partial solutions. More research is needed to develop standardized methods for each environmental component. However, the most appropriate and effective solution for now is to limit the release of microplastics into the environment.”

The article “The Future of Plastic”, published in Nature Communications (2018), concluded: “Durability—one of plastic’s greatest advantages—has become a curse: this very durability keeps plastic in the environment for hundreds of years.” This means we are facing a long-term microplastic pollution crisis, and scientists are striving to map microplastic and plastic waste pollution across Vietnam.

Source: The article “Evaluation of microplastic bioaccumulation capacity of mussel (Perna viridis) and surrounding environment in the North coast of Vietnam”

Translated by Phuong Ha
Link to Vietnamese version