A general description of the issue. Please let me know if you would like to add any correction/complement !

1. ArsenicArsenic groundwatergroundwater
contamination in Bangladeshcontamination in Bangladesh
Pierre DoPierre Do pierre.do@ipb.frpierre.do@ipb.fr

2. Maximum Contaminant Level (MCL)Maximum Contaminant Level (MCL)

3. Maximum Contaminant Level (MCL)Maximum Contaminant Level (MCL)
10 ppb (µg/L)
50 ppb Bangladesh

4. Global arsenic occurrenceGlobal arsenic occurrence

5. Arsenic occurrence in AsiaArsenic occurrence in Asia

6. Bangladesh and West Bengal (India) : whereBangladesh and West Bengal (India) : where
the most serious arsenic groundwater cases happen.the most serious arsenic groundwater cases happen.

7. 10 ppb (µg.L-1
)
1 ppb = 1/3000 getting cancer...
Maximum Contaminant Level (MCL)Maximum Contaminant Level (MCL)

8. 10 ppb (µg.L-1
)
50 ppb Bangladesh
Maximum Contaminant Level (MCL)Maximum Contaminant Level (MCL)

9. Survey conducted by
DPHE/UNICEF in 1998-99
(with the British Geological Survey
& Mott MacDonald Limited)
10 ppb 35-77 million
50 ppb 22 million
200 ppb 5,6 million
(MICS, 2009)
(< 150 m deep)

10. Sources of contaminationSources of contamination

11. Anthropogenic sourcesAnthropogenic sources

12. FertilizersFertilizers

13. Glass manufactureGlass manufacture Semiconductor chipsSemiconductor chips
Coal fly ashCoal fly ash

14. Pesticides
Wood preservatives
Glass manufacture
Coal fly ash
Semiconductor chips
Other miscellaneous uses of arsenic
Anthropogenic sourcesAnthropogenic sources

15. Arsenic can occur naturally...Arsenic can occur naturally...
Green Lake, New ZealandGreen Lake, New Zealand

16. ...and it causes elevated...and it causes elevated
arsenic concentrations.arsenic concentrations.

17. Weathered materials from theWeathered materials from the
Himalayas form aquifer sediments.Himalayas form aquifer sediments.

18. Ganges-Padma-Meghna river bringsGanges-Padma-Meghna river brings
sedimentary arsenic.sedimentary arsenic.

19. ArsenopyriteArsenopyrite

20. RealgarRealgar

21. Geochemical conditions :
Low pH, Eh
Competing and complexing ions
Reaction kinetics
Redox reactionsRedox reactions

22. Microbiological activityMicrobiological activity

23. Organic matter
(electron donor)
Anaerobic sediments
(reductive environment)
Microbial reduction of Fe(III) and As(V)
Release of As(III) from sediments
Microbiological activityMicrobiological activity

24. Groundwater flow regimeGroundwater flow regime controlscontrols......

25. …… the spatial variability of arsenicthe spatial variability of arsenic
concentrations in shallow aquifers.concentrations in shallow aquifers.

26. Main ways of human ingestion

27. Drinking contaminated waterDrinking contaminated water

28. Rice irrigated with arsenic-rich waterRice irrigated with arsenic-rich water

29. 85 % of As can be absorbed.85 % of As can be absorbed.

30. Arum (kochu)Arum (kochu)

31. 28 % of As can be absorbed.28 % of As can be absorbed.

32. Arsenic poisoning :Arsenic poisoning :
ArsenicosisArsenicosis

33. Untreated people experienceUntreated people experience
several stages of the disease.several stages of the disease.

34. Melanosis and keratosisMelanosis and keratosis

35. Enlargement of liver, kidneys, spleen
Abdominal pain, vomiting
Dryness/tightness in throat
Thirst, convulsions, cramps
Clammy sweats
SymptomsSymptoms

36. And later...

37. Nephropathy
Hepatopathy

38. Limb lossLimb loss

39. Skin, lung, bladder, prostate cancer
Immunological disorders
Diabetes
Reproductive & developmental problems
SymptomsSymptoms

40. “the worst mass poisoning
in human history”
Smith et al., 2000;
Smedley and Kinniburgh, 2002

41. One in five deaths in Bangladesh
cause by arsenic (Habib et al. 2010).

42. International
Community role ?

43. 4 million citizens have access to4 million citizens have access to
arsenic-safe water...arsenic-safe water...

44. …… so only 2.9 % of the population ofso only 2.9 % of the population of
Bangladesh (S. Ahuja, 2008).Bangladesh (S. Ahuja, 2008).

45. It appears that financial backers areIt appears that financial backers are
not very enthusiastic about arsenicnot very enthusiastic about arsenic
issues in Bangladesh...issues in Bangladesh...

46. Why do we have this BAD situation ?Why do we have this BAD situation ?

47. 1970's: Surface water was used.1970's: Surface water was used.

48. In order to prevent from diseases,In order to prevent from diseases,
various organizations decided to usevarious organizations decided to use
groundwater, naturally contaminated.groundwater, naturally contaminated.

49. Focus on bacterial contamination,Focus on bacterial contamination,
no elemental contaminationno elemental contamination

50. And today...And today...

51. Inadequate follow-through on theInadequate follow-through on the
strategy and guidelinesstrategy and guidelines

52. Inappropriate and inefficientInappropriate and inefficient
technology for arsenic mitigationtechnology for arsenic mitigation

53. Impractical approach : they do anImpractical approach : they do an
implementation plan before installingimplementation plan before installing
an appropriate technology.an appropriate technology.

54. ...of deep tube wells restricts...of deep tube wells restricts
installation of other technologies.installation of other technologies.

55. Poor support fromPoor support from
donor agencies...donor agencies...

57. Drink arsenic-free waterDrink arsenic-free water

58. Workable solutionsWorkable solutions

60. Implementation Plan for ArsenicImplementation Plan for Arsenic
Mitigation of Bangladesh 2004Mitigation of Bangladesh 2004
(GOB)(GOB)

61. Improved dug wellsImproved dug wells

62. Pond sand filtersPond sand filters

63. Large-scale surface water treatmentLarge-scale surface water treatment

64. Rain water harvestingRain water harvesting

65. Reliable arsenic removal technologyReliable arsenic removal technology

66. Piped water supply systemsPiped water supply systems

67. Piped water supply systemsPiped water supply systems

68. BibliographyBibliography

70. Bibliography
● The problem of arsenic contamination of
groundwater. Satinder Ahuja.
● Green Revolution Effects on Groundwater in
West Bengal, India. Angela Cesere, Alex
Aizenman, Mary Kate Heisler.

71. Bibliography
● web.worldbank.org
● www.earth.columbia.edu
● sitemaker.umich.edu
● www.bpedia.org

72. ““Be the change that you wishBe the change that you wish
to see in the world.”to see in the world.”
Mahatma GandhiMahatma Gandhi