1. M. Stute, L. van Geen, J. Graziano, H. Ahsan
Arsenic in Bangladesh groundwaters –causes, health effects and solutions
M. Stute, L. van Geen, J. Graziano, H. Ahsan
and many, many others……..
Columbia University, University of Chicago, Barnard College, Queens College, Dhaka University,…

2. Health effects of (chronic) Arsenic exposure
Skin lesions (few years of exposure)
Cardiovascular disease
Cancers of the skin, lung, liver, and bladder (several decades of exposure)
Children’s intellectual function

3. Cumulative hazard function of all-cause mortality by water arsenic concentrations
high As
low As
Argos et al, Lancet 376: 252-8, 2010

4. Arsenic in water– a global problem
BGS and DPHE (2001)

5. Population exposed to arsenic in drinking water (millions)
Country >50 mg/L >10 mg/L GN Income/capita*
1. Bangladesh
2. India ,070
3. China ,940
4. USA ,580
5. Myanmar ?
6. Pakistan
7. Argentina ,200
8. Vietnam ?
9. Nepal
10. Cambodia .
TOTAL *

6. Arsenic in Bangladesh
27 million people > 50µg/L (Bangladesh standard)
50 million people > 10µg/L
(US/WHO standard)

7. High spatial variability
> 50 µg/L
10-50 µg/L
< 10 µg/L
van Geen et al., 2002

8. Arsenic as function of depth
6000 wells
Van Geen et al., 2002

9. Causes? Need: arsenic in sediments (not much) organic matter
Natural
anthropogenic
reducing conditions (no oxygen)
Jessica Lieber

10. Arsenic and ground water flow
Radloff et al., 2010

11. As concentrations appear to increase with groundwater age
As concentrations appear to increase with groundwater age. As is flushed out of the aquifer by groundwater flow

12. How can we best reduce exposure to Arsenic?

13. Well switching
Well Arsenic (µg/L)
van Geen et al., 2002

14. Deep wells?
irrigation
Domestic
use As As As As As

15. Where do we stand?
Ahmed et al., Science, 2006