Vital Signs

Up to 60 million in Pakistan at risk of arsenic in water supply, study says

By Zamira Rahim, CNN
3 minute read
Published 1:16 PM EDT, Thu August 24, 2017
Because rice takes up arsenic more readily than other grains, the U.S. Food and Drug Administration is looking at the effects of long-term exposure to very low amounts of arsenic in rice and rice products. Rice's importance as a staple in regions around the world makes it a priority for food researchers. <br /><br />In April, the FDA <a href="http://www.fda.gov/Food/FoodborneIllnessContaminants/Metals/ucm367263.htm" target="_blank" target="_blank">proposed a limit of 100 parts per billion of inorganic arsenic</a> in infant rice cereal. <br /><br />Click through the gallery for more foods that can contain traces of arsenic, according to studies. <br />
Because rice takes up arsenic more readily than other grains, the U.S. Food and Drug Administration is looking at the effects of long-term exposure to very low amounts of arsenic in rice and rice products. Rice's importance as a staple in regions around the world makes it a priority for food researchers.

In April, the FDA proposed a limit of 100 parts per billion of inorganic arsenic in infant rice cereal.

Click through the gallery for more foods that can contain traces of arsenic, according to studies.
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In a <a href="http://ehp.niehs.nih.gov/1104619/" target="_blank" target="_blank">2012 study</a> by researchers at Dartmouth College, products that listed organic brown rice syrup as a primary ingredient, such as some <a href="http://www.cnn.com/video/data/2.0/video/health/2012/02/16/exp-cohen-and-arsenic-in-baby-formula.cnn.html">toddler formulas and cereal bars</a>, tested positive for higher levels of arsenic than products that didn't contain the ingredient or contained less of it.
In a 2012 study by researchers at Dartmouth College, products that listed organic brown rice syrup as a primary ingredient, such as some toddler formulas and cereal bars, tested positive for higher levels of arsenic than products that didn't contain the ingredient or contained less of it.
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The <a href="http://ehp.niehs.nih.gov/1104619/" target="_blank" target="_blank">Dartmouth study tested</a> two toddler formulas that listed organic brown rice syrup as a primary ingredient and 15 that did not. The study found that the formulas in which the syrup was a primary ingredient contained 20 times more arsenic than the other formulas. The baby pictured above is not associated with the study.
The Dartmouth study tested two toddler formulas that listed organic brown rice syrup as a primary ingredient and 15 that did not. The study found that the formulas in which the syrup was a primary ingredient contained 20 times more arsenic than the other formulas. The baby pictured above is not associated with the study.
Shutterstock
The U.S. Food and Drug Administration proposed in 2013 to <a href="http://www.fda.gov/Food/ResourcesForYou/Consumers/ucm271595.htm" target="_blank" target="_blank">limit the amount of inorganic arsenic</a> in apple juice to 10 parts per billion, the same level set for water. Because arsenic-based pesticides were commonly used in U.S. agricultural production up until 1970, trace levels of arsenic can be detected in some agricultural settings, which could lead to small amounts of arsenic in certain foods and beverages, including apples, according to the FDA.
The U.S. Food and Drug Administration proposed in 2013 to limit the amount of inorganic arsenic in apple juice to 10 parts per billion, the same level set for water. Because arsenic-based pesticides were commonly used in U.S. agricultural production up until 1970, trace levels of arsenic can be detected in some agricultural settings, which could lead to small amounts of arsenic in certain foods and beverages, including apples, according to the FDA.
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It is common for some arsenic to be found in seafood. However, <a href="http://www.atsdr.cdc.gov/csem/csem.asp?csem=1&po=5" target="_blank" target="_blank">higher concentrations of dietary organic arsenic</a> may be found in bivalve mollusks (clams, oysters, mussels) and crustaceans (crabs and lobsters), according to the Agency for Toxic Substances and Disease Registry. The organic forms of arsenic found in these types of seafood are generally considered nontoxic.
It is common for some arsenic to be found in seafood. However, higher concentrations of dietary organic arsenic may be found in bivalve mollusks (clams, oysters, mussels) and crustaceans (crabs and lobsters), according to the Agency for Toxic Substances and Disease Registry. The organic forms of arsenic found in these types of seafood are generally considered nontoxic.
Justin Sullivan/Getty Images
As part of its comprehensive look at rice in 2012, the FDA tested not only rice for arsenic levels, but also products containing rice. That includes <a href="http://www.fda.gov/food/foodborneillnesscontaminants/metals/ucm319870.htm" target="_blank" target="_blank">beer</a>, which sometimes uses <a href="http://www.consumerreports.org/cro/news/2014/01/fda-data-show-arsenic-in-rice-juice-and-beer/index.htm" target="_blank" target="_blank">rice as an ingredient</a>.
As part of its comprehensive look at rice in 2012, the FDA tested not only rice for arsenic levels, but also products containing rice. That includes beer, which sometimes uses rice as an ingredient.
Shutterstock
The <a href="http://www.fda.gov/Food/FoodborneIllnessContaminants/Metals/ucm275452.htm" target="_blank" target="_blank">FDA analyzed 142 samples of pear juice</a> and pear juice concentrate from 2005 to 2011. "Of these, 23 had levels of inorganic arsenic at or above 23 parts per billion, the level of concern for inorganic arsenic in pear juice." Those products were recalled, denied entry into the United States, or in a few cases the company received a warning letter.
The FDA analyzed 142 samples of pear juice and pear juice concentrate from 2005 to 2011. "Of these, 23 had levels of inorganic arsenic at or above 23 parts per billion, the level of concern for inorganic arsenic in pear juice." Those products were recalled, denied entry into the United States, or in a few cases the company received a warning letter.
Shutterstock
Foods in which arsenic may be present

Story highlights

A study estimates that millions have been exposed to high levels of arsenic in their water supply

Regularly drinking contaminated water can have serious health consequences

CNN  — 

Up to 60 million people living in Pakistan’s Indus Plain are at risk of being affected by high levels of arsenic in the region’s groundwater supply, according to a new study in the journal Science Advances.

An international team of scientists created a “hazard map” of locations at risk using water samples collected from almost 1,200 sites across the country, the majority of them from hand and motor pumps.

Using statistical modeling, the team also assessed environmental factors that may affect the movement of arsenic and calculated the size of populations at risk of exposure. They concluded that there was widespread arsenic contamination in the Indus Plain, from where 50 million to 60 million people get their groundwater.

An Indian flood-affected villager gives drinking water to her child at a makeshift camp in Banmankhi area in Purnia district of India's northeastern state of Bihar, some 440 km north-east of Patna, on September 5, 2008. Rescue workers in flood-hit northern India have brought over 800,000 people to safety, but tens of thousands more are still believed to be trapped, officials said. Large swathes of the already impoverished state of Bihar were flooded after defences upstream in Nepal broke, shifting the flow of the Kosi river away from its normal course and onto farmland. Around 100 people are confirmed to have died in the floods, but the real number is certain to be far higher as many were simply washed away by the deep water and strong currents that swept through rural areas. AFP PHOTO/Diptendu DUTTA (Photo credit should read DIPTENDU DUTTA/AFP/Getty Images)
An Indian flood-affected villager gives drinking water to her child at a makeshift camp in Banmankhi area in Purnia district of India's northeastern state of Bihar, some 440 km north-east of Patna, on September 5, 2008. Rescue workers in flood-hit northern India have brought over 800,000 people to safety, but tens of thousands more are still believed to be trapped, officials said. Large swathes of the already impoverished state of Bihar were flooded after defences upstream in Nepal broke, shifting the flow of the Kosi river away from its normal course and onto farmland. Around 100 people are confirmed to have died in the floods, but the real number is certain to be far higher as many were simply washed away by the deep water and strong currents that swept through rural areas. AFP PHOTO/Diptendu DUTTA (Photo credit should read DIPTENDU DUTTA/AFP/Getty Images)
DIPTENDU DUTTA/AFP/Getty Images

Related article Arsenic-polluted water linked to cancer in India

“This alarmingly high number of people likely affected demonstrates an urgent need to test all drinking water wells in the Indus Plain,” the team said in a statement.

The researchers have urged authorities to treat affected wells accordingly. Arsenic does not have a smell or a taste, and there are no short-term symptoms after consuming it. However, drinking contaminated water regularly could lead to serious illnesses including lung cancer and cardiovascular diseases, the team said.

The study “doesn’t mean every well in the area is affected, but the easiest thing to do and the first obvious step is to test each and every well,” said Joel Podgorski of the Swiss Federal Institute of Aquatic Science and Technology, the study’s lead author. “Once it’s known that a well has arsenic in it, people can shift to a safe water source. Or a filter could be used.”

‘Humans have exacerbated the issue’

The World Health Organization estimates that 200 million people worldwide are affected by arsenic contamination. The organization’s guidelines for concentration of arsenic in drinking water permit up to 10 micrograms per liter; Pakistan’s guidelines allow up to 50 micrograms per liter.

But use of either measurement would not change the number of people who the team believes to be at risk, Podgorski said, with most supplies in the area breaching 50 micrograms per liter.

File - In this May 20, 2009 file photo a glass of white wine is swirled during a tasting in Oakville, Calif. More than two dozen California vintners are facing a lawsuit claiming their wines contain dangerously high levels of arsenic. The industry group Wine Institute dismissed the allegations as "false and misleading." (AP Photo/Eric Risberg, File)
File - In this May 20, 2009 file photo a glass of white wine is swirled during a tasting in Oakville, Calif. More than two dozen California vintners are facing a lawsuit claiming their wines contain dangerously high levels of arsenic. The industry group Wine Institute dismissed the allegations as "false and misleading." (AP Photo/Eric Risberg, File)
Eric Risberg/AP/FILE

Related article Should you be worried about arsenic in California wine?

Podgorski added that the arsenic naturally occurred in the groundwater but that “it’s possible in some cases that humans have exacerbated the issue.”

“We’ve alluded in the study to a correlation between arsenic levels and high organic pollution in groundwater,” he said. “Sometimes, human and animal waste getting into a shallow well can make the issue worse locally, as it causes a different type of of arsenic release.”

The team also found a correlation between irrigated areas and high arsenic levels in the water, though Podgorski stressed that this could be a coincidence.

Beyond further testing, the team suggested emergency measures such as health intervention programs for those affected.

The need to know more

“We need to know now how many people are affected as well as at risk,” said Mohammad Shamsudduha, a research fellow and hydrogeology expert at University College London who was not involved in the research. “I’m quite convinced by their data, as they’ve collected so many samples.”

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    He added that the fact that the group has linked contamination to the number of people exposed is impressive. “Previously, the numbers of those at risk were very speculative. It’s also a study examining arsenic levels in Pakistan at a national level. Much of the data I’ve looked at has been at a local level,” he said.

    Podgorski said Syed Ali Musstjab Akber Shah Eqani, a co-author on the study, is collecting further groundwater samples in Pakistan for the team’s next phase of research.

    “We also have in the pipeline a similar study on fluoride levels across Pakistan, which is also an issue,” Podgorski said.

    Shamsudduha hopes the team’s research will increase awareness of arsenic contamination in Pakistan.

    “There’s always a pressure put on officials with a high impact publication and the consequent media coverage,” he said. “It’s just a dream that every well will be tested before it is sunk, which everyone in this field would recommend, But possibly, this study may trigger policy changes so that testing for arsenic contamination is more common.”