"Magic tree seeds" to purify dirty water

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GLOBAL: “Magic tree seeds” to purify dirty water

http://www.irinnews.org/Report.aspx?Reportid=91879

BANGKOK, 10 February 2011 (IRIN) - One solution to the water woes of many of the world’s poor may lie in the pea-sized seeds of the widely grown Moringa oleifera tree, experts say. “The Moringa oleifera [seed technique] can be an important, sustainable and affordable method towards waterborne disease reduction and can improve the quality of life for a large proportion of the poor,” Micheal Lea, author and researcher with Clearinghouse, an Ottawa-based organization researching low-cost water purification technologies, told IRIN. According to Lea’s 2010 publication, seeds from the Moringa, a tree (also described as a shrub) which grows in Africa, Central and South America, the Indian subcontinent and Southeast Asia, can be crushed into a powder and mixed with surface water to produce a 90-99 percent bacterial reduction, making untreated water safely drinkable.

The technique is not new. Communities in Sudan have been using the multi-purpose Moringa tree as a source of food and as a water purifier for centuries. The plant is fast-growing, nutritious, edible and drought resistant, and can be grown in your backyard. Its seeds are soft and can be crushed using everyday tools, such as a spoon and a bowl. (see video) The ability to purify water using such accessible techniques, and others has significant life-saving potential.

Factbox

Seed filtration steps
a)Pick and dry the seeds
b)Grind seeds into powder
c)Mix the powder with a little water to make a paste
d)Add paste to the dirty water
e)Stir
f)Set container aside to let it settle
g)After 1-2 hours, pour water into a clean container

Globally, approximately 1.1 billion people do not have access to drinking water and diarrhoea remains the leading cause of illness and death, according to the latest UN Office for the Coordination of Humanitarian Affairs report.

With the number of people without access to safe water expected to rise to two billion by 2025, several independent Moringa tree cultivation projects have started in the past few years.

Moringa plantations in Ghana In the Breman Baako village of Ghana, the Moringa Community organization has cultivated Moringa plantations which several thousand people live off as a food source. “The Moringa is protein and vitamin rich, so people eat the leaves and use the seeds as a spice on food,” said Abu Bakkar Abdulai, Ghana country director of the Moringa Community. “But there is a need for clean water so we are trying to inform the communities about this other technique as well.”

Limitations

While the technique has potential, Kebreab Ghebremichael, a water purification expert with the UN Educational, Scientific and Cultural Organization (UNESCO) Institute for Water Education, says it would be best used at the household level.

“The technique is easy and inexpensive and many people already have this tree in their backyards,” said Ghebremichael, who studied the Moringa tree seed purifying technique for his PhD. "However, non-processed Moringa cannot be used in centralized large water systems… because the organic content from the seed may give taste and odour problems if it stands for a long time before consumption.”

The Moringa seed purification technique works best for purifying surface water, such as rivers, streams, lakes and ditches, but not for underground water sources. So it would not be able to resolve the problem of natural arsenic poisoning that afflicts many populations in Asia. “This method is not a silver bullet, but could be used during emergencies and where people have no resources to treat the water they drink from,” Lea said.
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