Scientists Discover A Type Of Aquatic Moss That Can Remove Arsenic From Drinking Water


A study published in the journal Environmental Pollution hails the discovery of a new method of purifying arsenic-contaminated water so that it’s once again safe to drink, ScienceDaily reports.

The credit for this unexpected find goes to researchers from Stockholm University in Sweden, who have experimented with a type of aquatic moss called Warnstofia fluitans and found that it can remove arsenic from drinking water.

Their study revealed that W. fluitans can cleanse drinking water of both arsenite and arsenate, removing up to 82 percent of the arsenic from a container of contaminated water.

Remarkably, it only takes an hour for the aquatic moss to yield this impressive result, the Swedish researchers note in their paper.

“Our experiments show that the moss has a very high capacity to remove arsenic,” said study co-author Arifin Sandhi, a research assistant at the university’s Department of Ecology, Environment and Plant Sciences.

Sandhi, who conducted the W. fluitans experiments, revealed that the aquatic moss decreases the arsenic content in contaminated water to such a degree that it no longer poses a threat to people. And it all happens within 60 minutes.

In a news release on the formidable find, Stockholm University describes the discovery as “an environmentally friendly way to purify water of arsenic,” suggesting that W. fluitans could be grown in “streams and other watercourses with high levels of arsenic” in order to improve the quality of drinking water.


This type of aquatic moss is indigenous to northern Sweden, where arsenic-contaminated water is an issue, especially in mining areas. Although the use of arsenic compounds in wood products has been banned since 2004, arsenic continues to seep both into the ground and the drinking water, as a result of mining.

The arsenic contamination is also facilitated by the composition of the bedrock, which in certain parts of the country naturally includes arsenic, notes the university news release.

The research team was led by Maria Greger, an associate professor at the university and Sandhi’s direct boss. Greger expressed her confidence that W. fluitans could help end the arsenic contamination problem in the region.

Petri dish containing a sample of the aquatic moss Warnstofia fluitans.
Featured image credit: PanekWikimedia Commons/Resized

“We hope that the plant-based wetland system that we are developing will solve the arsenic problem in Sweden’s northern mining areas,” she said in the news release.

Going forward, the goal is to implement this eco-friendly filtration system so that the water is purified of arsenic before being used in irrigation or as drinking water, Greger explained.

As she pointed out, this method would prevent the arsenic from being absorbed by plants and thereby make its way into crops. In Sweden, the type of crops that are usually affected by arsenic contamination include wheat, root vegetables, and leafy greens.

However, the W. fluitans water filtration system is not limited to these examples and could be used by different countries to save other types of crops, such as rice plantations.