Moringa seeds show promise in removing microplastics from water

New Delhi: A natural and centuries-old solution may hold the key to tackling one of today’s most pressing environmental challenges, microplastic contamination in drinking water.

Researchers from São Paulo State University have found that seeds from the moringa tree can effectively remove microplastics from water, offering a sustainable alternative to chemical treatment methods.

“Moringa trees have been used to purify water for millennia, with evidence of their use by ancient Greeks, Romans and Egyptians,” said Adriano Gonçalves dos Reis, study author and professor at the university’s Institute of Science and Technology.

The research focuses on the seeds’ role as a natural “coagulant”, a substance that binds tiny particles together, making them easier to filter out. With rising global concern over microplastic pollution, the team explored whether moringa could help address this growing threat.

Microplastics, often smaller than a human hair, have been detected in ecosystems worldwide, from deep oceans to mountain peaks. A 2024 global study found them in 83% of tap water samples, raising alarm about their presence in human bodies, including vital organs.

In laboratory tests, scientists used microplastics averaging 18.8 micrometers in size and found that moringa seed extracts removed up to 98.5% of these particles from tap water.

“This efficiency is roughly comparable to a commonly-used chemical coagulant, aluminum sulfate,” the study noted. However, moringa showed an edge in certain conditions. “Moringa seeds performed even better than alum in more alkaline water,” researchers found.

Experts say the benefits go beyond efficiency. “Using a natural product to replace an aluminum-based filtration system may offer a cheaper and more sustainable solution,” said Matthew Campen, a distinguished professor at the University of New Mexico who was not involved in the study.

He added that such alternatives could also reduce environmental damage linked to aluminum mining. Researchers highlighted additional advantages of moringa seeds, noting they are renewable, biodegradable, and produce less sludge compared to chemical coagulants.

They also pose fewer toxicity risks, unlike aluminum, which has been linked to neurodegenerative concerns at high levels.

Despite the promising findings, challenges remain. One moringa seed can treat around 10 liters of water, making large-scale urban application difficult.

“While this is promising, it would require a very large quantity of seeds for large urban treatment plants handling high flows,” said Gonçalves dos Reis. The method may be more practical for small communities or regions where access to chemical treatment is limited.

Scientists also caution that increased use of seeds could leave organic residues in water, requiring further purification. Additionally, more research is needed to determine effectiveness against nanoplastics, the smallest particles most likely to enter the human body.

Still, experts emphasize the urgency of such innovations. “Humans are exposed to increasing levels of microplastics and nanoplastics, and this trend is unlikely to change for many decades to come,” Campen warned.

As research continues, Moringa seeds could emerge as a low-cost, eco-friendly tool in the global fight against plastic pollution.