God, Hope & Helping Others
POSTED ON APRIL 23, 2018
By Heather Callaghan, Editor
When pollution strikes – or builds up over the years – leave it to humble water plants to patiently and quietly take the abuse.
There are a few plants already known that can be used to sop up pollution. Seaweed is known to absorb ocean toxins. Orange peels can soak up mercury. Moringa seeds can clean and purify drinking water.
Now, Stockholm University researchers have discovered that the moss known as Warnstofia fluitans – or floating hook moss – can clear enough arsenic from a contaminated container of water in one hour to make it safe enough to drink. The research was published in Environmental Pollution.
To illustrate, research assistant Arifin Sandhi said:
Our experiments show that the moss has a very high capacity to remove arsenic. It takes no more than an hour to remove 80 per cent of the arsenic from a container of water. By then, the water has reached such a low level of arsenic that it is no longer harmful to people.
The moss purifies by quickly absorbing and adsorbing (in which something sticks to the surface, basically) arsenic from water. The discovery could easily pave the way for an eco-friendly way to purify water. One possible scenario is to grow the moss in streams and other waterways with high levels of arsenic, note the researchers.
“We hope that the plant-based wetland system that we are developing will solve the arsenic problem in Sweden’s northern mining areas,” says Maria Greger, associate professor at the Department of Ecology, Environment and Plant Sciences at Stockholm University and leader of the research group.
Arsenic finds its way into the ground and water systems naturally; but also through industry, now mostly from mining. When arsenic-polluted water is used to irrigate crops, it is absorbed by the plants and ends up in the food chain. In Sweden, wheat, root vegetables, leafy greens, and other crops suffer from this; In many places, rice routinely tests positive for arsenic. Arsenic poisoning is widespread in some countries – for example, an estimated 57 million people in the Bengal basin drink groundwater with arsenic levels above the World Health Organization’s standard. In the U.S., arsenic is found in the ground waters of the southwest, parts of New England, Michigan, Wisconsin, Minnesota, the Dakotas, and more are known to have significant concentrations of arsenic in groundwater.
How much arsenic we consume ultimately depends on how much of these foods we eat, as well as how and where they were grown. Our aim is that the plant-based wetland system we are developing will filter out the arsenic before the water becomes drinking water and irrigation water. That way, the arsenic will not make it into our food.
While this is a high aim – a truer aim would be to head off the pollution at its origin and prevent it from spilling out into the crop system. Whether the pollutant is naturally occurring or not – there needs to be a better prevention than letting one ecological system take the burden.