Arsenic exposure from drinking water, and all-cause and chronic-disease mortalities in Bangladesh (HEALS): a prospective cohort study.
BACKGROUND
Millions of people worldwide are chronically exposed to arsenic through drinking water, including 35-77 million people in Bangladesh. The association between arsenic exposure and mortality rate has not been prospectively investigated by use of individual-level data. We therefore prospectively assessed whether chronic and recent changes in arsenic exposure are associated with all-cause and chronic-disease mortalities in a Bangladeshi population.


METHODS
In the prospective cohort Health Effects of Arsenic Longitudinal Study (HEALS), trained physicians unaware of arsenic exposure interviewed in person and clinically assessed 11 746 population-based participants (aged 18-75 years) from Araihazar, Bangladesh. Participants were recruited from October, 2000, to May, 2002, and followed-up biennially. Data for mortality rates were available throughout February, 2009. We used Cox proportional hazards model to estimate hazard ratios (HRs) of mortality, with adjustment for potential confounders, at different doses of arsenic exposure.


RESULTS
407 deaths were ascertained between October, 2000, and February, 2009. Multivariate adjusted HRs for all-cause mortality in a comparison of arsenic at concentrations of 10.1-50.0 microg/L, 50.1-150.0 microg/L, and 150.1-864.0 microg/L with at least 10.0 microg/L in well water were 1.34 (95% CI 0.99-1.82), 1.09 (0.81-1.47), and 1.68 (1.26-2.23), respectively. Results were similar with daily arsenic dose and total arsenic concentration in urine. Recent change in exposure, measurement of total arsenic concentrations in urine repeated biennially, did not have much effect on the mortality rate.


CONCLUSIONS
Chronic arsenic exposure through drinking water was associated with an increase in the mortality rate. Follow-up data from this cohort will be used to assess the long-term effects of arsenic exposure and how they might be affected by changes in exposure. However, solutions and resources are urgently needed to mitigate the resulting health effects of arsenic exposure.


BACKGROUND
US National Institutes of Health.
Argos
Maria
M
Department of Health Studies, University of Chicago, Chicago, IL 60637, USA.
Kalra
Tara
T
Rathouz
Paul J
PJ
Chen
Yu
Y
Pierce
Brandon
B
Parvez
Faruque
F
Islam
Tariqul
T
Ahmed
Alauddin
A
Rakibuz-Zaman
Muhammad
M
Hasan
Rabiul
R
Sarwar
Golam
G
Slavkovich
Vesna
V
van Geen
Alexander
A
Graziano
Joseph
J
Ahsan
Habibul
H
D000293:Adolescent; D000328:Adult; D000368:Aged; D020261:Arsenic Poisoning / Q000401:mortality*; D001459:Bangladesh / Q000453:epidemiology; D002908:Chronic Disease / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014874:Water Pollutants, Chemical / Q000009:adverse effects*; D014877:Water Pollution, Chemical / Q000009:adverse effects*; D014881:Water Supply; D055815:Young Adult
D014874:Water Pollutants, Chemical