revista ecociencias
Chilean researcher develops sustainable method using seaweed to remove arsenic from water
Jan 14, 2026
Biochar obtained from brown algae could become an innovative solution to protect public health in areas affected by natural water pollution in Chile
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An innovative method based on biochar derived from seaweed is emerging as a sustainable alternative to combat arsenic contamination in freshwater sources intended for human consumption, a silent problem affecting various regions of the country.
The technology was submitted as a patent application to the National Institute of Industrial Property (INAPI) by Dr. Loretto Contreras Porcia, director of the Laboratory of Ecology and Molecular Biology in Algae (LEBMA) at Andrés Bello University (UNAB), a researcher at the Quintay Marine Research Center (CIMARQ UNAB), and the Millennium Institute SECOS. The proposal combines circular economy principles, technological innovation, and public health protection.
The invention—registered in December 2025—describes a method for adsorbing arsenic from freshwater using biochar obtained from the brown algae Macrocystis pyrifera, a species abundant on the Chilean coast. The material is activated using ferric chloride, which significantly increases its capacity to retain this metalloid. The patent protects both the biochar production process and its application in drinking water purification systems.
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Arsenic in water: a threat to health ​
The presence of arsenic in water represents a serious risk to human health. According to Dr. Contreras, its effects depend on the dose, the chemical form, and the duration of exposure. In the short term, ingesting contaminated water can cause gastrointestinal symptoms such as vomiting, abdominal pain, and diarrhea.
However, the greatest danger is associated with chronic exposure. “Prolonged exposure can cause skin lesions, various types of cancer, neurological and cardiovascular disorders, as well as glucose metabolism disorders, including diabetes,” warns the academic.
The severity of the problem is reflected in the classification of the International Agency for Research on Cancer (IARC), which places arsenic compounds in Group 1, meaning they are carcinogenic to humans. “The worrying thing is that relatively low concentrations can cause serious health effects,” adds Contreras.
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