In recent years, the presence of microplastics in drinking water It has become one of the major environmental and health concerns on a global scale. These tiny particles, almost always invisible to the naked eye, have been detected in rivers, seas, aquifers, and even in household tap water, including in Europe.
In this context, a tree very well known in tropical regions is capturing the attention of the scientific community: the MoringaIts seeds, used since ancient times to clarify water, have been shown in the laboratory to be able to remove up to 98% of certain microplastics, opening the door to a possible change of approach in the treatment of wastewater and drinking water.
What are microplastics and why are they such a concern?
Microplastics are fragments of plastic material less than five millimeters in size that They come from degraded packaging, tires, textiles, paints and a multitude of everyday products. Over time, solar radiation, friction, and other physical processes break them down to microscopic sizes.
These particles end up in the water systems through rainSurface runoff, urban and industrial wastewater, and the atmosphere itself all contribute to their spread. Once in rivers and seas, they can be ingested by aquatic organisms and enter the food chain, indirectly reaching humans as well.
The problem is not limited to just their size: plastics can transport chemical additives and attached contaminantsThis multiplies the risks. Even smaller nanoplastics are especially worrying because they can penetrate biological barriers.
Several studies indicate that these tiny particles can reach vital organs such as lungs, kidneys, liver, heart, or brainas well as circulating in the bloodstream. Although research is still ongoing, they have been associated with possible effects on the cardiovascular system, the respiratory system, and reproductive health.
Moringa, a "miracle tree" with a long history in water purification
Moringa, popularly known as miracle treeIt has been cultivated for centuries in warm climates due to its many uses. It is used in food, traditional medicine, sustainable agriculture, and, since ancient times, in water purification.
It is believed that they were already used in ancient Egypt moringa seeds to reduce water turbidity and eliminate bacteria, taking advantage of its natural coagulating properties. Today, this traditional practice is being revisited with modern scientific tools.
This tree is characterized by its fast growthIts remarkable drought resistance and ability to thrive in arid and degraded soils make it a valuable asset. It requires minimal inputs, can act as a carbon sink, and helps maintain and even enhance local biodiversity.
In addition to its potential in water purification, moringa is used in the treatment of malnutrition and various diseasesIt is also used in nutritional and cosmetic products. This combination of uses makes its cultivation of added interest in rural development and circular economy projects.
The study that shows that moringa eliminates up to 98% of microplastics
A team from the Paulista State University (UNESP), in BrazilA study led by researcher Gabrielle Batista has analyzed in detail the ability of moringa seeds to remove microplastics from water. The results were published in the journal ACS Omega.
At work, a saline extract from moringa seeds, which was used as a coagulant, and was compared to aluminum sulfate (alum), the most widely used chemical in many treatment plants, also in Europe, to clarify water.
Both coagulants were tested against PVC microplastic particles of about 15 micrometers in diameterThis size is especially problematic because it is small enough to pass through standard filters but large enough to carry toxic substances attached to it.
The results showed that Moringa and alum managed to eliminate more than 98% of the particles of PVC present in the water under the laboratory conditions used. In other words, the effectiveness of the plant-based solution was at least comparable to that of the conventional chemical coagulant.
How moringa works as a natural coagulant
The mechanism that explains this behavior is based on the coagulation and flocculationMany microplastic particles have a negative electrical charge, which causes them to repel each other and remain dispersed in the water, thus evading physical filters.
When moringa extract or alum is added to water, it partially neutralizes that chargeAs the electrical repulsion decreases, the particles begin to move closer together and join together, forming larger aggregates called flocs.
These resulting flocs are large enough to be retained by a sand filter or other mechanical systems commonly used in treatment plants. In this way, the process allows the capture of what previously escaped traditional methods.
The study also confirmed that moringa was effective in both online filtration as in direct filtrationThis implies that a specific flocculation phase, which usually requires additional equipment and significant energy consumption, could be omitted.
Another highlight is that the moringa-derived coagulant showed a greater stability over a wide pH rangemaintaining its effectiveness without needing to adjust the chemical conditions of the water as much as often happens with alum.
Advantages over chemical coagulants used in Europe
Currently, many wastewater and drinking water treatment plants in Europe use combined physical and chemical methods to reduce the presence of microplastics. Among the chemicals, aluminum sulfate remains one of the star coagulants.
Alum is effective, but it is not without its drawbacks. Side effectsImproper or excessive use can increase the concentration of aluminum in treated water, which has been linked in some studies to possible neurological disorders, including Alzheimer's disease, although definitive evidence is still under scientific debate.
Furthermore, the coagulation process with aluminum sulfate generates large volumes of sludge These wastes are difficult to manage. They often end up in landfills and, over time, can release compounds that seep into the soil and nearby bodies of water.
To all this must be added the environmental impact linked to the production of alum itself. It requires the bauxite mining open-pit mining in regions such as Australia, Brazil, Guinea, Guyana, or Jamaica, which can lead to deforestation, habitat loss, and emissions associated with transportation and refining.
In this scenario, moringa presents itself as a plant-based, renewable and non-toxic alternativeIts cultivation does not require complex industrial infrastructure, it can be integrated into agroforestry projects and, if managed sustainably, it significantly reduces the environmental footprint of the water treatment process.
Microplastics and regulations in Europe: where does moringa fit in?
The European Union has been strengthening its microplastics control protocols in drinking water and wastewater, aware that it is an emerging contaminant with potential impact on public health.
Despite these regulatory advances, current treatment methods may not be fully effective against the smaller particlessuch as nanoplastics or certain fine microplastics that pass through standard filters and are not always retained in traditional coagulation and sedimentation stages.
Research on moringa comes in this context, offering a additional tool which could be integrated into existing treatment systems. In theory, it could complement or partially replace chemical coagulants, especially in facilities seeking to reduce their reliance on mineral or synthetic products.
For Europe, where there is an extensive network of wastewater treatment plants and drinking water purification facilities, the adoption of plant-based coagulants such as moringa would require Technical adjustments, large-scale trials and a rigorous evaluation of the logistical costs associated with the supply of seeds and their processing.
In parallel, the potential use of moringa could prove particularly interesting in rural areas, small towns or cooperation projects where access to industrial chemicals is limited or too expensive, and where local tree cultivation can be integrated into the community economy.
Environmental and social benefits of moringa cultivation
From an environmental point of view, moringa offers several advantages: its rapid growth and drought resistance This makes it an ideal candidate for reforestation and degraded soil restoration programs, also in Mediterranean countries with water stress.
Its ability to thrive in poor soil makes it interesting as carbon sink and soil improvement elementhelping to fix organic matter and slow erosion in vulnerable environments. At the same time, its flowers and leaves contribute to local biodiversity, providing habitat and food for insects and other organisms.
On a social and economic level, the cultivation of moringa can generate new income opportunities For local farmers, it benefits from the sale of seeds, leaves, oil, and other derivatives. Its strategic value is further strengthened by its use in water treatment, particularly in regions with limited access to clean drinking water.
In Spain and other European countries with arid or semi-arid zones, some projects are already exploring the agronomic potential of moringaAlthough it is still a minority crop, the growing demand for natural solutions for purification and nutrition could gradually boost its implementation.
However, it is advisable to plan its expansion using criteria of sustainability and adaptation to the territoryavoiding introducing it into sensitive ecosystems where it could behave as an invasive species or alter existing ecological balances.
Limitations of the method and pending challenges of moringa
Despite the promising results, the authors of the UNESP study themselves warn that there are still important questions to be resolved before moringa can be widely incorporated into treatment plants.
One of the points highlighted is the release of dissolved organic carbon during the coagulation process with the seed extract. This carbon can interfere with subsequent stages of water treatment, for example, by increasing the organic load that other processes, such as disinfection, must manage.
It is also necessary to check how this system behaves in actual operating conditions, with large flow rates and water of different chemical composition, beyond the controlled environment of the laboratory where the first tests have been carried out.
Another challenge involves logistics: it would be necessary to guarantee a stable and sustainable supply of seedsas well as developing simple processes for obtaining the coagulant extract on an industrial scale without losing effectiveness.
Finally, it will be essential for future studies to thoroughly analyze the final quality of treated water with moringa, including possible by-products or residues, and compare its behavior with that of conventional coagulants in different climatic and regulatory scenarios, both in Europe and in other regions.
Nevertheless, the growing interest in natural solutions with a lower environmental impact has placed moringa on the radar of government agencies, scientists, and companies in the water sector. If upcoming research confirms its performance and safety, this fast-growing tree could become a key element in the fight against microplastics and in the modernization of water treatment, offering Spain and the rest of Europe an additional tool to protect public health and the environment.