1. Tuesday February 16th 2010 Richard Wilson Mallinckrodt Research Professor of Physics Harvard University Completion and sustaining safe drinking water in Bangladesh http://arsenic.ws http://physics.harvard.edu/~wilson/arsenic/ arsenic_project_introduction.html

2. Nuclear Physics High energy particle physics Proton Radiotherapy Risk Analysis Nuclear Reactor safety Chemical Carcinogens animal/man comparison Energy and environment problems What not to do about climate change Responses to terrorist Risks

3. KERATOSIS BOWEN”S CARCINOMA DYSPIGMENTATION GANGRENE

4. 1982: R.C Saha observed keratoses and dyspigmentation in West Bengal -IGNORED 1995 DCH physicians saw lesions in Bangladesh. 30,000,000 drinking water with >50 ppb arsenic ACTION BEGAN in 1998 (1) Use uncontaminated deep aquifer (2) Treat the water at household level (3) return to surface waters ALL WILL WORK Each has different problems of sustainability

5. Replacing water Well switching only 30% of tube wells contaminated BUT 80% in some villages Deep tube wells Dhaka uses these not so good in Jessore

6. Removing arsenic: This seems first choice of many people by town by village by household Can it be maintained?

7. In 1965 Dipenkar Chakriborti reported that 70% of household filters in West Bengal were abandoned NGOs bought them gave them to villagers and walked away Villagers could not cope

8. When there is a local group it works better (Abul Munir of Kushtia and SONO filter) but now overloaded Village size units can educate a caretaker for 1000 people Das Gupta West Bengal SIDDKO

9. Surface water GoB policy in 2003 yet no emphasis on sanitation ICDDR’B said nothing Adopted by Dhaka Community Hospital Dugwells River Sand filters Pond Sand filters Rainwater collection

15. Sanitary well: no animals fall in no buckets! (L) Electrically pumped to tank (R) Lady has running water for first time in history

16. Piped water system very popular among women who carry the water Enables more families to be served by one well. Large (INDARA) wells can serve 50 families (1) Maintenance cost spread (2) Large size ensures oxidization and inhibits arsenic release (3) Easier to keep free of bacteria But electricty only on twice a day because of cost

17. >10 after 23 days and reached from 35 to 180+ in the water samples of all dugwells at the end of the month. Fig 1: Faecal coliforms count in water samples of 10 dugwells (DW2, DW3, DW6, DW7, DW8, DW10, DW21, DW29, DW34, and DW66) of Pabna district in the month of July. No. of days after chlorination Fae cal coli for m cou n/ 100 ml

18. Chlorination method of DCH: Shock Chlorination Does not work for flooded tube wells. (Luby, Johnston 2006) Works for sufcae dugwells BUT CHLORINE TASTE IS NOT GOOD About 0.5 mg/Liter 1/50 of that used by DCH for shock treatment In last 10 years we have lots of measurements

19. BUT low level daily chlorination does not work in a dugwell. Sides and bottom soak up chlorine Should work in overhead tank and in last box of river sand filters I propose to study this in the next year

20. I know of no one who drinks Dhaka or Pabna water without boiling YET I am happy to drink RSF or dugwell water But I would still like to have it verifiable by a cheap field test

21. A lot of work on Chlorination at Point of Use Karachi, Zambia, Kenya, and Bolivia vey polluted wells but diarhea reduced Cost less than bottled water

22. MY recommendation for Bangladesh If deep tube wells ONLY FOR HOUSEHOLD: NEVER FOR IRRIGATION Use surface waters for irrigation ONLY build to WHO standards (DCH) River water filters Pond sand fikters Dugwells Chlorine (household bleach every week in summer Use piped water system; it leads to the long term emphasize large systems: Indara wells

23. ALL DCH tests are on the web at: http://DCHTests.arsenic.ws http://physics.harvard.edu/~wilson/ arsenic/remediation/dugwells/DCHtests Some project well tests also: