November 21, 2025
SURABAYA – New research has found that the air in several major Indonesian cities is contaminated with microplastics, posing threats to public health and the environment.
The study, conducted by the Ecological Observation and Wetlands Conservation Foundation (ECOTON) in collaboration with the Society of Indonesian Environmental Journalists (SIEJ) between May and July 2025, examined air quality in 18 cities across the country.
The research employed passive air deposition monitoring, placing glass petri dishes at a height of 1-1.5 meters which corresponds to the human breathing zone at representative locations in each city to collect airborne particles. The samples were then subsequently analyzed under a microscope to identify the types of microplastics present.
The research found that all cities surveyed were contaminated with microplastics to varying degrees.
Central Jakarta and South Jakarta recorded the highest concentrations, with 37 and 30 microplastic particles collected from every 9-square-centimeter petri dish during the two-hour sampling period, respectively.
They were followed by Bandung in West Java (16 particles), Semarang in Central Java (13), Kupang in East Nusa Tenggara (13), Denpasar in Bali (12) and Surabaya in East Java (12).
Analysis of the samples showed that most microplastics were small fragments (53 percent) and fibers (46 percent), with a very small amount present as thin films (0.6 percent).
Read also: Insidious pollutants: Microplastics floating in Jakarta’s air, water
The analysis found several types of plastics in the air. PTFE, often used in nonstick cookware and electrical insulation, epoxy, which is found in adhesives and coatings and polyisobutylene, commonly used in tires and sealants, were all detected. Plastics from the polyolefin family, including widely used packaging materials like polyethylene and polypropylene, were also present.
Sofi Azilan Aini, ECOTON’s microplastic research volunteer coordinator, said the main source of airborne microplastics is the widespread burning of plastic waste, which accounts for 57 percent of contamination.
“Poor waste management has forced many people to burn trash, which significantly contributes to microplastic pollution,” she said in a recent press briefing.
Despite being banned under Law No. 18/2008 on Waste Management, open burning is still common because of growing waste volumes and limited disposal options. ECOTON observed this practice in 10 of the 18 surveyed cities, including Jakarta, Bandung, Semarang and Surabaya.
Sofi explained that previous international studies show that burning plastic releases microplastic particles and synthetic aerosols that can remain in the air and travel hundreds of kilometers. When these particles interact with water vapor in the atmosphere, they can fall with rain, creating the phenomenon now known as microplastic rain.
Aside from waste burning, other significant sources of microplastic pollution include the transportation sector, through tire, asphalt and rail wear, which accounts for 33.3 percent of contamination.
Microfibers released from washing clothes, especially synthetic fabrics like polyester and nylon, contribute 27.7 percent, while the breakdown of household plastic packaging adds 22 percent, and industrial and construction activities account for 16.6 percent.
Read also: ‘They’re everywhere’: microplastics in oceans, air and human body
Rafika Aprilianti, head of ECOTON’s Microplastic Laboratory, warned that microplastics pose serious health risks to humans. Their surfaces can bind with toxic substances, including heavy metals and hazardous chemicals, making them up to 106 times more toxic than the individual substances alone.
“Exposure to microplastics can lead to respiratory inflammation, oxidative stress, cellular damage, hormonal disruption and an increased risk of cancer because of the accumulation of chemical additives in the body,” she said.
She urged the government to take urgent action, including stricter enforcement of the open burning ban, better waste sorting systems, expansion of zero-waste city programs and regular monitoring of microplastic levels in air and rainwater. Public awareness campaigns and environmental education are also critical to reduce plastic burning and cut reliance on single-use plastics.