Boffins at MIT have run some tests and found out that if you peel the bark off a Pine tree branch and pour water through the stick, then it will block upto 99% of e-coli bacteria and a host of other bad stuff giving up to four liters of drinkable water per day. This makes it a lot cheaper than any current commercial water filtration implementation in the market and a lot more scalable.
Dirty water is a major cause of mortality in the developing world. ‘The most common water-borne pathogens are bacteria (e.g. Escherichia coli, Salmonella typhi, Vibrio cholerae), viruses (e.g. adenoviruses, enteroviruses, hepatitis, rotavirus), and protozoa (e.g. giardia). These pathogens cause child mortality and also contribute to malnutrition and stunted growth of children.’ People have been working on engineering cheaper and cheaper filtration systems for years, but now a group of researchers has found a promising and simple solution: a tree branch. ‘Approximately 3 cm^3 of sapwood can filter water at the rate of several liters per day, sufficient to meet the clean drinking water needs of one person.’
Of course there are some caveats; the system can trap most types of bacteria, the smallest of which measure about 200 nanometers but currently cannot trap viruses most of which are much smaller in size. Also, the stick needs to be kept wet or the filtration is not that effective.
The researchers have published a paper in this week’s journal PLoS ONE where they go over their findings and demo this functionality. Check it out if you have some time.
I am definitely adding this to my things to know in case of an emergency list. 🙂
Thanks to Slashdot for the initial story.
Additional reading: Need a water filter? Peel a tree branch – MIT News Office
– Suramya