Sometimes, the simplest technologies have the greatest impact on people''s lives. See as an example the system for
filtering
mobile company''s Swiss Vestergaard Frandsen, baptized, LifeStraw ( "canudo of life"). It is a blue plastic tube - but much more that a wholesale
canudinho common - containing filters that make drinking water contaminated with microorganisms that cause cholera, typhoid fever and diarrhea.
The filters, manufactured in halogen resin, killing nearly 100% of bacteria and about 99% of the viruses that pass through the LifeStraw. The University of North Carolina at Chapel Hill tested the canudo with a sample of water containing the bacteria Escherichia coli B and Enterococcus faecalis, in addition to the virus MS2 colifago, and more iodine and silver. The results indicate that the LifeStraw filtered all the contaminants at levels that do not pose a further risk to the health of anyone who eats the water.
However, the canudo not filter heavy metals like iron or fluoride or remove parasites such as giárdia or criptosporídio, although the CEO of the company, Mikkel Vestergaard Frandsen, saying that there is a version of LifeStraw available for groups of humanitarian aid in Bangladesh and India capable of
filtering arsenic.
With less than 25 cm, the canudo can filter up to 700 liters of water - estimate of the annual consumption of one person. The LifeStraw should be thrown away when their filters are too clogged to allow the passage of water, which usually happens after a year of use.
Source: Scientific America, ediçào 70, March 2008
Http://www2.uol.com.br/sciam/noticias/filtro_completo_em_um_canudinho.html