The world arsenic Catastrophe: Helping the Overwhelmed
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Transcript of The world arsenic Catastrophe: Helping the Overwhelmed
The world arsenic The world arsenic Catastrophe:Catastrophe:
Helping the OverwhelmedHelping the Overwhelmed
American Chemical SocietyThursday March 30th 2006
Richard WilsonMallinckrodt Research Professor of Physics
Harvard University
http://arsenic.wshttp://phys4.harvard.edu/~wilson/arsenic_project_introduction.html
30,000,000 exposed in Bangladesh
above US EPA standard
A catastrophe that makes Chernobyl look small!
others in: West Benglal
NepalThailandVietnamPakistan
How does the world help Bangladesh?
Three vital items
(1) Make sure measurements of arsenic and coliform bacteria are
regular and accurate
(2) work with local community - they must make
decisions and follow up and
(3) get funds direct to villagers (avoid sticky fingers
as much as possible)
My recommendation to the Government of Bangladesh
Find out which (NGO) is doing a competent job(Discuss on web, conferences,
WHO etc)
Get money direct to them
Even if not economically the “best”
doing nothing is expensive especially in good will.
1998 (DCH conference)urged immediate action:
(1) Measure every wellGreen for OK
Red for don’t useEncourage well switching
(2) Purify Water at House levelwith simple equipment
(3) Encourage deep wells (below clay layer)
(4) Encourage solutions that lead to the long term
Labelling wells was partially successful
30% of people switched wells but ~10 million people helped!
67% switched when a massive education campaign (Columbia-U.Dhaka)
Some wells badly labeledPerhaps status of wells changed
MY CONCLUSION BETTER EDUCATION CAMPAIGN NEEDED
on switching
Uncritical use of Arsenic Removal Systems (ARS)
May even be counterproductive.
AN OLD REMEDY
So Moses brought Israel from the Red Sea, and they went out into the wilderness of Shur; and they went three days in the wilderness and found no water. And when they came to Marah they could not drink of the waters of Marah for they were bitter. And they murmered against Moses saying “What shall we drink?” and he cried unto the Lord; and the Lord showed him a tree, which when he had cast into the waters , the waters were made sweet”Exodus 15:22-5
• In West Bengal several hundred have been installed.
80% are not functional.• (6th report: Jadavpur University)
BUT they seem to work when there is “backup”
• Sengupta of Bengal College
• SONO filters near Kushtia•
DCH tests have not been as good as hoped
• Also NOT a long term solution
Deep wells have worked in Dhaka for a long time!
Badly installed wells could bring water down
from upper aquifer.
BUT 98% likely to work at least 20 years
Maybe for ever.
Long shot:Professor Charles Harvey
(MIT) thinksthe problem is pumping
water from anoxic region.Possible Solution:Pump concentrated
oxidants into the well. Works for a week;
tried with massive amounts of oxidants January 2006.
We will see.
Bangladesh Policy Use surface water when
possibleRainwater Collection
Improved (sanitary) DugwellsPond Sand FiltersRiver Sand Filters
We must avoid bacteriaand know we have avoided bacteria
Key is measurementMeasurement Cheapest if a large
number supplied from one unit
January 2000If you ask villagers to put up with your
measurements of water (Harvey)and epidemiological studies (Christiani)
you have to do something for them
So we gave DCH a $10,000 check for new water resources
(about $60,000 by now)January 2001 we gave them a kit
(University of Surrey) for measuring coliform bacteria
Then we got Ashok Khosla (New Delhi) to send his (JAL-TARA) measuring kit
which they used.
POND SAND FILTERfor several hundred people
• Originally built in 2001-2
• this was high in Coliform.
• It was rebuilt with more stages and by January 2004 low coliform were measured.
Dhaka Community Hospital(experts in community health)
has been installing Sanitary surface “dugwells”
where >80% tubewells contaminated WHO standards; Covered;
Originally limed, (note that BRAC and Grameen Bank did not follow
these standards)
now chlorinated (every 3 months)(now) measured regularly
More recently pumped to tank and pipeline
to give running waterVERY POPULAR
Capital cost $6/person
• 66 seemed OK in Pabna region.• (6 now abandoned)• Checked, limed, tested every 3
months for a year.• Low arsenic (LOD 3 ppb)• 0-10 coliform 0 fecal coliform• But questions were asked by Feroze
and others• 2005 tests on 10 wells looked bad. • Maybe they ONLY tested just after
liming. Now they claim chlorinating every 3 months OK (<10 fc structures/dl)
• Jabed Yousuf (DCH) is now in charge of getting measurements and should have been here but DHS did not give him a visa
• Why the long delay?
• Importance of discussing with villagers
• U Dhaka questionnaire shows
• People willing to pay 20 X as much for piped water as for arsenic free water
Enables larger systems to supply more villagers
(maintenance spread over more people)
Piped water system leads naturally to central system in
the long term
• I suggest piped water is an imporatant option to suggest to people independent of where the water comes from
My recommendation to the Government of Bangladesh
Find out which (NGO) is doing a competent job(Discuss on web, conferences,
WHO etc)
Get money direct to them
Even if not economically the “best”
doing nothing is expensive especially in good will.
The whole job can be done for
ONLY $300 million!$1 each American
World Bank provided a $50 million 1% loan that Jim Wolfensohn expected to be spent with 18 months
and Kuwait Fund can help
when asked by governments
Meanwhile please support the public foundation of
your choiceDugwell Foundation
http://www.dugwellfoundationusa.org
(Meera Smith)
Arsenic Foundationhttp://arsenicfoundation.com
(Richard Wilson)