School program in rural Bangladesh reduces arsenic exposure, study shows
March / April 2016 | Volume 15, Issue 2
By Shana Potash
A mother in rural Bangladesh goes about her task of collecting household water from a well outside her home. She may not know the water contains high levels of arsenic, or that using a different well could be lifesaving. An NIH-supported study found that an arsenic education program based in elementary schools was successful in convincing families to switch to safe water sources.
Arsenic is naturally occurring and can leach into groundwater from rocks and soil. Contaminated water is a problem in many countries, but is particularly severe in Bangladesh. Wells, drilled decades ago to avoid surface water that was spreading diarrheal disease, tapped into groundwater that naturally contains arsenic. The WHO estimates as many as 45 million people in Bangladesh may be at risk of exposure.
Installing new, safe wells in a community doesn't necessarily mean people will use them, researchers say. Arsenic contamination isn't readily apparent because the metal is colorless, tasteless and odorless. Toxic effects such as cardiovascular disease, skin lesions, and cancer in adults, and intellectual impairment and behavioral problems in children, take time to show up. And, there's the inconvenience of switching from a nearby contaminated well, to a safe one that requires carrying heavy water a longer distance.
Investigator Dr. Khalid Khan proposed training teachers to communicate the dangers of arsenic and the need to switch to safe wells. Khan, a native of Bangladesh, says educators in developing countries are pillars of the community - if a teacher asks students to convey a message to their parents, it's taken very seriously.
"The idea was the children would get information in the earliest stages of their life," Khan explains, "It could basically save them for their entire life, and their families also could benefit."
Fourteen schools and roughly 800 children, ages 8 to 11, participated in the study. An NGO partner installed safe wells. Half the teachers were trained and given arsenic education posters and books with rhymes and stories to use in classrooms. At baseline and in follow up, well water was tested, students were quizzed on their knowledge of arsenic and their urine was analyzed for signs of the metalloid.
Students who received arsenic education were five times more likely to switch to a safer well, compared to control groups. The children receiving the intervention also had a significantly greater decline in urinary arsenic, a biomarker of exposure, than the controls. And, there was a substantial increase in knowledge about arsenic after the intervention. Teachers and students who didn't receive the education as part of the study were provided the information as soon as the project ended.
The findings come as investigators are learning more about arsenic's effect on children. In a related study, Columbia University investigators showed again that the higher the arsenic exposure the lower the child's intelligence. After new wells were installed, researchers saw an improvement in the working memory component of intelligence but not in full-scale IQ.
Dr. Joseph Graziano, Khan's mentor, leads the National Institute of Environmental Health Sciences (NIEHS) Superfund Research Program at Columbia that is studying the health effects, geochemistry and remediation of arsenic and manganese. Graziano says Khan's approach is a useful model and could be used for other health topics.
"Education paid off," Graziano says of Khan's project. "This message that was provided to elementary school children worked its way up in the family household so that mom became educated. School-based programs are affordable and can have a powerful impact."
Khan's own education in the process included environmental health, epidemiology, biostatistics, geoscience, spatial mapping and the opportunity to learn from a multidisciplinary group of researchers. He and another Bangladeshi scientist received their doctoral degrees with support from Fogarty's International Training and Research in Environmental and Occupational Health (ITREOH) program. Khan is now an assistant professor of environmental health at Indiana University Bloomington and is the principal investigator on other research efforts in Bangladesh.
The school project had a ripple effect beyond the participants, reaching thousands of families, Khan and Graziano say. They were both moved by the community's gratitude and Khan was pleased to make a contribution to his country. "I was able to develop expertise at Columbia University and take that back to Bangladesh and implement it on the ground," he says. "It was kind of amazing."
- NIEHS Superfund Research Program at Columbia University
- Related NIH-supported project: Building capacity to reduce arsenicosis in Bangladesh
- Evaluation of an elementary school-based educational intervention for reducing arsenic exposure in Bangladesh
Environmental Health Perspectives, December 2015
- Child intelligence and reductions in water arsenic and manganese: a two-year follow-up study in Bangladesh
Environmental Health Perspectives, December 29, 2015 (online)
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