Arsenic, once used in pesticides, has been a worry across the U.S. for many years. Food production pollution and natural contamination (arsenic is found in certain rock) has contaminated water and food across the country, from Maine to California's Central Valley.
But one recent scientific breakthrough could help clean up water for good.
Image via iStock.
Meet the arsenic-eating power of warnstarfia fluitans, better known to the outdoorsy as floating hook moss.
Aquatic moss in Stockholm University greenhouse. Photo by Arifin Sandhi, used with permission.
It's mostly found in the Great Lakes region, but floating hook moss also has a home in northern Sweden. That part of Sweden has been the home of iron mining for years, and a type of iron pyrite called arsenopyrites piles up and leaches arsenic out into water supplies. Researches at Stockholm University observed the floating hook moss living in the contaminated water, in water no plant should be able to survive in.
"We thought that this plant could be used as an arsenic phytofilter plant species in a constructed wetland system," says Arifin Sandhi, a doctoral candidate at the university.
Could this moss clean up the water?
In general, plants are extremely effective at cleaning up heavy metals and poisons, which they evolve as a defense mechanism. They take it out of their environment, bind it up in their tissues, and essentially bury it inside themselves. As long as we don't eat it for a snack, and as long as the plant stays alive, it's effectively gone.
The researchers discovered that the floating hook moss not only sucks up arsenic, it sucks it up faster than you can watch your favorite TV show.
When introduced into a container of water with dangerous levels of arsenic, the moss filtered 80% of the chemical out of the water in less than an hour.
Image via Hermann Schachner/Wikimedia Commons.
Even more surprising was that the moss seemed to thrive in the arsenic. It continued to live and grow with as much as double the arsenic it takes to kill other types of moss.
Why does it suck up so much arsenic so fast? Theories abound, and we'll have to wait for molecular biologists to weigh in for any clear answers. The most likely theory, at the moment, is that the moss does it as a form of immunization. By taking in the arsenic and incorporating it into its tissues, it both reduces the chances of the arsenic damaging it externally and gives every branch of the moss a better chance to survive.
This mighty moss has the potential to quickly clean up water sources far beyond northern Sweden.
With it's poison-sucking abilities, the floating hook moss could be used in special gardens planted and grown near sources of pollution. In several towns in France, for example, these handpicked gardens are so good at their jobs that when you reach the final outlet for their sewage treatment plants, you can take a nice dip in the water and never even know where it came from.
The moss is found across the planet, so there's not a huge risk of introducing an invasive species to natural waterways. That said, care will have to be taken that the moss doesn't run out of control, but its speed means that it can be introduced and removed far faster than machine-based solutions.
We don't have to accept the pollution of the past (or present) as the way of the future.
We can do our part by petitioning to build pollution-guzzling gardens and, in places where we can grow aquatic gardens and where we know they won't be invasive, growing them ourselves.
We can make changes, often faster and more powerfully than we thought possible with a little help from the Earth itself.