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Leveraging UV Light for Effective Algal Toxin Removal in Drinking Water

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By Environmental Health Program August 4, 2025

Harmful algal blooms (HABs) pose significant risks to public health and the environment by producing dangerous toxins like microcystin-LR (MC-LR), which can exceed safety limits in drinking water. Research by the U.S. Geological Survey, The Ohio State University, and Boise State University evaluated ultraviolet (UV) light treatments for reducing microcystin levels, comparing traditional UV254 with the newer UV222 method. The study found that UV222 is three times faster and produces fewer harmful byproducts, making it a safer and more efficient option for treating drinking water contaminated with microcystins.

Harmful algal blooms (HABs) pose significant risks to public health and the environment by producing dangerous toxins like microcystin-LR (MC-LR), which can exceed safety limits in drinking water. Research by the U.S. Geological Survey, The Ohio State University, and Boise State University evaluated ultraviolet (UV) light treatments for reducing microcystin levels, comparing traditional UV254 with the newer UV222 method. The study found that UV222 is three times faster and produces fewer harmful byproducts, making it a safer and more efficient option for treating drinking water contaminated with microcystins.

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