Nav: Home

Villagers follow the geology to safer water in Bangladesh

November 05, 2018

Annual Meeting of The Geological Society of America, Indianapolis, Indiana

Indianapolis, IN, USA: Water researchers have found a way to fight the "king of poisons" that accounts for one of every 20 deaths in Bangladesh.

Arsenic has a long, sordid history as a poison once used in very high doses to assassinate aristocrats, but it is also a common natural element found in well water around the world. In groundwater, too much arsenic is still a killer, but nowhere more than in Bangladesh. The south Asia country is home to more than 10 million shallow, hand-pumped wells that yield water that often exceeds the World Health Organization (WHO) arsenic guidelines of 10 micrograms per liter.

"Groundwater is popular because it is generally free of bacterial pathogens, unlike surface water," explained Alexander van Geen of Columbia University, Lamont-Doherty Earth Observatory. Groundwater must travel through rocks and sediments, which filters out most harmful bacteria. The same process adds minerals to groundwater -- including a lot of arsenic in some shallow wells of Bangladesh.

In 2000, van Geen and his team surveyed 6,000 wells, and then recruited a health study cohort of 12,000 people. Then in 2013, they conducted larger survey of 50,000 wells serving 350,000 people. They found that government wells that were more than 150 meters deep were typically low in arsenic. However, they also found that the more than 900 deep were distributed in a way that suggested they had been taken by elite and politically connected households, and were not accessible to the public. This interpretation has since been confirmed by development economist Mushfiq Mobarak at Yale University, van Geen explained.

"Millions of people rely on water supplies that are contaminated with naturally occurring arsenic," says Sarah Ruth, a director of the National Science Foundation's Dynamics of Coupled Natural and Human Systems Program, which funded the research. "Consumption of arsenic-contaminated water, or the rice crops irrigated with it, can have severe health effects, including a variety of cancers and increased child mortality."

The hijacking of the deeper government wells by some households has meant that other villages can't get good water, however. People in the study area now generally understand that deeper is better, van Geen said. As a result, they have been taking it on themselves to drill deeper wells, often encountering low arsenic water well before 150 meter depth. A new survey of the water in the study area recently documented a jump in the proportion of villagers drinking from wells meeting the WHO guideline. Only 25 percent of wells were safe in 2000, compared to 70 percent in 2018.

"This is good news," said van Geen of this year's survey of water. "This is for a population of 12,000 living within a 25 square kilometer area that we've been tracking since 2000. Urine arsenic data confirm that villagers aren't just telling us what they know what we'd like to hear." Most of the decline is attributable to households reinstalling wells to a greater depth at their own cost.

"Some villages have figured this out; others have not," said van Geen. His team is trying to convey this information to the villages through water tests, so people can see the difference for themselves. "Geology and geochemistry causes the problem, but it's also the solution. The arsenic is avoidable without having to resort to water treatment."

Van Geen will be presenting his latest water survey results at the meeting of The Geological Society of America in Indianapolis, Indiana, on Tuesday, 6 Nov.
-end-
Contact:

Alexander van Geen
Email: avangeen@ldeo.columbia.edu
Phone: +1 646 379 7843.

Abstract:

How Earth Processes Can Poison Millions but also Provide A Solution: The Case of Well-Water Arsenic In South Asia
Presentation time: 10:50 a.m.
https://gsa.confex.com/gsa/2018AM/webprogram/Paper319704.html
NSF grant ICER 1414131

Session:

T46. From Local to Global--Why Geology Matters for Human Health
https://gsa.confex.com/gsa/2018AM/webprogram/Session45535.html
Tuesday, 6 November 2018: 8:00 AM-12:00 PM
Sagamore Ballroom 6 (Indiana Convention Center)

The Geological Society of America, founded in 1888, is a scientific society with members from academia, government, and industry in more than 100 countries. Through its meetings, publications, and programs, GSA enhances the professional growth of its members and promotes the geosciences in the service of humankind. Headquartered in Boulder, Colorado, GSA encourages cooperative research among earth, life, planetary, and social scientists, fosters public dialogue on geoscience issues, and supports all levels of earth-science education.

Geological Society of America

Related Arsenic Articles:

Arsenic in drinking water may change heart structure
Among young adults, drinking water contaminated with arsenic may lead to structural changes in the heart that raise their risk of heart disease.
Arsenic-breathing life discovered in the tropical Pacific Ocean
In low-oxygen parts of the ocean, some microbes are surviving by getting energy from arsenic.
Parboiling method reduces inorganic arsenic in rice
Contamination of rice with arsenic is a major problem in some regions of the world with high rice consumption.
UN University compares technologies that remove arsenic from groundwater
A UN University study compares for the first time the effectiveness and costs of many different technologies designed to remove arsenic from groundwater -- a health threat to at least 140 million people in 50 countries.
Arsenic for electronics
The discovery of graphene, a material made of one or very few atomic layers of carbon, started a boom.
More Arsenic News and Arsenic Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...