Sphagnum moss could be used as a cheap, reusable filter for poor families with metal-contaminated water. I used a Scanning Electron Microscope and Energy Dispersion X-Ray spectrometer, to learn where Sphagnum stores the metals it absorbs. Is it possible to remove metals from Sphagnum cristatum after absorption? I tested this by placing Sphagnum in an acid solution after allowing it to absorb copper. To find out if Sphagnum could remove trace amounts of dissolved arsenic I prepared moss-filtered and control solutions for analysis in an Inductively Coupled Plasma-Mass Spectrometer. Finally, I applied it as a filter for contaminated water, using metal-rich water from my family’s well. I found that copper bound itself all over the surfaces of moss cells, and was easy to remove by soaking in a low pH solution. Sphagnum could be reused as a filter if it was dried between uses, and would remain effective. Sphagnum wasn’t very effective at removing arsenic, but it did remove other metals at low concentrations. Sphagnum is very cheap and transportable, and by showing that Sphagnum is reusable, it makes it even more cost effective; a single filter could last for years. For many places in the world, where people can’t afford the water filters they need, Sphagnum could save lives. Also, Sphagnum reusablility means people wouldn’t need to continually harvestit and harm the environment to obtain filters.Arielle, thanks for this great piece of research. I'm sure the permaculture community will put the information to good use.
Friday, May 05, 2006
Cheap, natural solution to heavy metals in water
Arielle Garrett of Stellys Secondary School, Saanichton, British Columbia has discovered a cheap, natural way to remove heavy metals from water. The following is a summary of her findings: