The moringa tree is a short-lived, fast-growing, drought-resistant tree native to northern India. Its seeds and fruit are valued for their flavor and nutritional value and the tree is known as “the miracle tree” for its use in traditional medicine.
Moringa trees have been used to purify water for millennia. The seeds contain cationic proteins that neutralize charged impurities in water, causing clumping and sedimentation in water. Powdered seeds are mixed with water and over a few hours, sediments will sink, and clear water can be siphoned off the top. New research by Brazilian and UK scientists have found that extracts from moringa seeds are just as effective at removing microplastics from drinking water.
A 2024 study found microplastics in 83% of tap water tested around the world. The tiny bits of plastic make their way into our bodies, including our brains, reproductive organs, and cardiovascular systems. How this impacts human health is still undetermined.
There are chemicals that cause similar clumping behavior such as aluminum sulfate, or alum. But moringa seeds are even better at it as well as being renewable, biodegradable, and have fewer toxicity concerns. Alum can be toxic at high levels.
Using a natural product to replace an aluminum-based filtration system may offer a cheaper and sustainable solution to the removal of microplastics. There are limitations, however. It would require a very large quantity of seeds to supply a large urban treatment plant that can handle high water flows.
Nevertheless, identifying solutions for the microplastics problem is very valuable.
By Randy Simon
Randy Simon has over 30 years of experience in renewable energy technology, materials research, superconductor applications, and a variety of other technical and management areas. He has been an officer of a publicly-traded Silicon Valley company, worked in government laboratories, the aerospace industry, and at university research institutions. He holds a PhD in physics from UCLA. Dr. Simon has authored numerous technical papers, magazine articles, energy policy documents, online articles and blogs, and a book, and holds seven patents. He also composes, arranges and produces jazz music