THURSDAY, Feb. 16, 2012 (HealthDay News) -- A sweetener used in many organic foods may be a hidden source of arsenic, a new study suggests.
Researchers at Dartmouth College also noted that the sweetener, organic brown rice syrup, is found in some infant formulas. Their report appears in the Feb. 16 issue of Environmental Health Perspectives.
Arsenic is a natural element that can contaminate groundwater. As the Dartmouth team explained, rice may be particularly prone to contamination because it pulls in arsenic from soil. There are no federal limits currently set for arsenic levels in food, although there are limits set for arsenic levels in water.
Study author Dr. Brian Jackson, director of the Trace Element Analysis Core Facility at Dartmouth, set out to determine the concentrations of arsenic in commercial food products containing organic brown rice syrup, including infant formula, cereal/energy bars and high-energy foods used by athletes. Jackson and his colleagues bought commercial food products containing organic brown rice syrup and compared them with similar products that did not have rice syrup in them.
In all, 17 infant formulas, 29 cereal bars and three energy shots were all purchased from local stores in the Hanover, N.H., area.
Of the 17 infant milk formulas tested, two had listed organic brown rice syrup as the primary ingredient. These two formulas, one dairy-based and one soy-based, had arsenic levels that were more than 20 times greater than the other formulas, the researchers found.
One of the infant formulas had a total arsenic concentration that was six times the U.S. Environmental Protection Agency's safe drinking water limit of 10 parts per billion (ppb) for total arsenic. The amount of inorganic arsenic, the most toxic form, averaged 8.6 parts ppb for the dairy-based formula and 21.4 ppb for the soy formula, the study said.
Cereal bars and high-energy foods using organic brown rice syrup also had higher arsenic concentrations than those without the syrup, the study showed.
"The baby formula findings are concerning," Jackson said. Infants and people who eat gluten-free diets, which are largely rice-based, are most at risk for consuming too much arsenic via food, he explained, while "the risk for the occasional cereal bar eater is low."
The Organic Trade Association said Thursday that the findings "add to a growing body of evidence supporting the conclusion that arsenic dietary exposures pose a serious food safety problem... Regardless of how it is raised, rice plants growing in soils still contaminated with arsenic will extract the element from the soil, and some will be present in the grain harvested from those plants."
"The Organic Trade Association [OTA] agrees with the researchers that it is time for the U.S. Food and Drug Administration and U.S. Environmental Protection Agency to work together to set and enforce regulatory limits on arsenic in our food supply.Both the government and food industry must determine now whether any consumer food products containing brown rice sugar, whether conventional or organic, contain arsenic levels high enough to justify product recalls or changes in ingredients," the association said in its statement. "Any rice product destined for baby food or children's food should come only from regions known to have arsenic-free soils. Prevention is a core principle of organic farming and food processing, and will drive the response to this new challenge across the organic food industry."
This isn't the first time arsenic levels in foods have made the headlines.
Dr. Mehmet Oz, host of "The Dr. Oz Show," caused a public health stir in 2011 when he reported that roughly one-third of apple juice samples he'd tested had arsenic levels exceeding 10 parts per billion, the limit for drinking water. At first, Oz was criticized by the U.S. Food and Drug Administration, but his findings were later confirmed by a Consumer Reports study that showed many apple and grape juice samples were tainted with arsenic.
What exactly are the health risks with arsenic?
"All we can fall back on is what we know about exposure through drinking water; risk of certain cancers or heart disease are slightly elevated in drinking water with a certain level of arsenic," Jackson said. "Moms should know that these rice-based formulas may contain arsenic and should limit exposure. Look at the ingredients when you purchase formula."
Connie Diekman, director of university nutrition at Washington University in St. Louis, said consumers shouldn't panic over the Dartmouth findings.
"As a registered dietitian, I would encourage consumers to not worry about this study, but to use it as a reminder that foods that grow in soil are growing with a wide variety of chemicals, both those found naturally in the soil and those that may be there from use of chemicals to foster growth," she said. "Whether the amount of any one chemical is enough to worry about is still a question that needs better research. Focusing on single foods as 'dangerous' or 'harmful' ignores how those foods impact the whole diet.
"Whether organic foods contain more arsenic, or other minerals, than conventional foods is hard to estimate, but this study does remind us that organic is not necessarily equal with healthier/better for you/safe from harm," she added. "Ask a registered dietitian to help decipher new studies, and how those studies translate to their individual eating goals."
Learn more about arsenic in foods and drinks at the U.S. Food and Drug Administration.