Microplastics Detected in Every Rain Sample Across Jakarta — Coastal Sites See Highest Deposition

Researchers in Indonesia have detected tiny plastic particles in every rainwater sample collected across Jakarta since 2022, raising new concerns about airborne contamination and its potential impacts on health, soil and urban environments.

Key Findings

A multi-year investigation by Indonesia's National Research and Innovation Agency (BRIN) found microplastics in all samples taken across multiple sites in the capital. Lead researcher Muhammad Reza Cordova said teams identified synthetic fibers and plastic fragments in every sample, including polyester, nylon, polyethylene and polypropylene. The highest deposition — about 15 particles per square metre per day — was recorded at coastal locations.

How Microplastics Enter Rain

According to the study, common sources of these particles include:

• Synthetic fibers shed from clothing and textiles
• Dust from vehicles and tyres
• Burning of plastic waste
• Degradation of discarded plastics in open environments

Once airborne, these fragments can adhere to atmospheric moisture and return to the ground with rainfall.

Health and Environmental Concerns

While rainwater itself is not inherently dangerous, microplastics may carry chemical additives or adsorb pollutants during transport. That creates potential exposure routes through inhalation, drinking water or contaminated food. Scientists caution the full long-term health impacts remain unclear, but early studies suggest possible risks such as endocrine (hormonal) disruption, oxidative stress and tissue damage.

Microplastics also affect soil ecosystems. Research published in Environmental Science & Technology indicates microplastics can disrupt microbial activity, reduce nutrient availability and increase emissions of nitrous oxide — a potent greenhouse gas — which could worsen local and global environmental stresses.

Policy Response and Practical Steps

In response to the findings, Indonesian authorities have pledged to ban all plastic waste imports by the end of the year and are urging improved waste collection and safer disposal practices. Officials emphasize public education and stronger management systems to reduce the volume of contaminated material entering the environment.

Individuals can help limit local contributions by reducing single-use plastics, avoiding open burning of waste and choosing reusable alternatives for everyday items.

Promising Solutions

New research highlights mitigation options: vegetated green roofs — roofs covered with plants — have been shown in one study to filter up to 97.5% of microplastics from rainwater, offering a scalable urban strategy to improve air and water quality while also cooling neighborhoods.

"These microplastics come from synthetic fibers in clothing, dust from vehicles and tyres, burning of plastic waste, and degradation of plastics in open environments," said Muhammad Reza Cordova of BRIN.

While many questions remain about long-term impacts, the Jakarta study underscores the global nature of microplastic contamination and the need for coordinated policy, infrastructure and individual actions to reduce risk.