UNESCO Introduces Low-Cost Water Filter to Remove Arsenic
From: Vern Weitzel <firstname.lastname@example.org
With potentially poisonous arsenic in drinking water being both
a natural phenomena and a toxic by-product of mining, mineral
extraction and coal-burning electricity production, the United
Nations Educational, Scientific and Cultural Organization
(UNESCO) today unveiled a low-cost filter, made from an indus-
trial waste product that is designed to remove the harmful sub-
Prevention is the only recourse since there is no medical treat-
ment for intoxication by arsenic-contaminated water, the agency
said in launching the innovation at its Paris headquarters.
"The technology we developed is based on arsenic absorption with
iron oxide coated sand. If you produce the material commercially
it is very expensive and when its absorption capacity is ex-
hausted, you have to replace it and dispose of the waste," said
Branislav Petrusevski, Director of the UNESCO-IHE Institute in
Delft, The Netherlands, which offers post-graduate training and
research programmes on water and the environment to developing
Instead, the Institute team recycled iron oxide coated sand pro-
duced as a by-product in groundwater treatment plants. The fil-
ter is easy to use, requires no power and can be produced lo-
cally. The "family" filter produces 100 litres of arsenic-free
water per day, enough to supply the needs of 20 people.
"Plants in many countries around the world use natural sand for
iron removal and have to replace it after a certain number of
years. We found that this material, now coated with iron oxides,
is an excellent absorbent for removing arsenic from water. It is
free of charge and consequently the technology based on its use
is cheap," Mr. Petrusevski said.
He pointed out that the UN World Health Organization has set the
healthy maximum of arsenic in water at 0.01 milligrams per li-
tre, but added that according to WHO estimates "arsenic levels
in groundwater in Bangladesh, for example, are as high as 1.8
milligrams per litre."
Since February 2004, 14 "family filters" have been tested in ru-
ral Bangladesh where highly-contaminated groundwater has arsenic
levels of up to 0.5 milligrams per litre. After more than 18
months of daily use, 12 of them were still producing arsenic-
free water without needing replacement of the sand absorbent.
Another 1,000 filters would be distributed in Bangladesh in the
project's second phase. Arsenic is a serious problem in many
other countries, including Argentina, Chile, China, Ghana, Hun-
gary, India, and Mexico and the United States.
For more details go to UN News Centre at http://www.un.org/news