Arsenic has been found in some foods that use organic brown rice syrup as a sweetener, including infant formula and cereal bars, according to a new study by researchers at Dartmouth College. The majority of the detected arsenic, a contaminant often found in rice, was the type that is known to be a human carcinogen.
Important findings of the study, published online Feb. 16 by the peer-reviewed journal Environmental Health Perspectives include:
Two of 17 infant formulas tested listed organic brown rice syrup as the primary ingredient. One had a total arsenic concentration that was six times the federal limit of 10 parts per billion (ppb) for total arsenic in bottled or public drinking water. This is particularly worrisome for babies because they are especially vulnerable to arsenic’s toxic effects due to their small size and the corresponding arsenic consumption per pound of body weight.
Twenty-two of 29 cereal bars or energy bars tested listed at least one of these four rice products—organic brown rice syrup, rice flour, rice grain or rice flakes – among the top five ingredients. The seven other bars were among the lowest in total arsenic, ranging from 8 to 27 ppb, while those containing syrup or other forms of rice ranged from 23 to 128 ppb.
Tests of high-energy products known as “energy shots” that are used by endurance athletes and others showed that one of the three gel-like blocks contained 84 ppb of total arsenic, while the other two contained 171 ppb.
The Dartmouth researchers conclude that given the increasing prevalence of hidden arsenic in food, “there is an urgent need for regulatory limits on As (arsenic) in food.” They also cited Consumer Reports’ recent investigation, which found elevated levels of arsenic in apple and grape juices, as further evidence that U.S. consumers are being exposed to worrisome concentrations of arsenic in foods and beverages. Legislation was introduced Feb. 8 in the U.S. House of Representatives calling on the Food and Drug Administration to establish standards for both arsenic and lead in fruit juices; there are currently no federal thresholds for arsenic in juices or most foods.
As previously reported, other research from Dartmouth published online in late 2011 suggested that many people in the U.S. may be exposed to potentially harmful levels of arsenic through consumption of rice. Studies by other researchers also have shown that rice can be a significant source of dietary exposure to this toxin. Rice is among the plants that are unusually efficient at taking up arsenic from the soil, and much of the rice produced in the U.S. is grown on land formerly used to grow cotton, where arsenical pesticides were widely used for many years, just as they were in orchards and vineyards.
“In the absence of regulations for levels of arsenic in food, I would certainly advise parents who are concerned about their children’s exposure to arsenic not to feed them formula where brown rice syrup is the main ingredient,” says Brian Jackson, Ph.D., lead author of this latest study and a member of Dartmouth’s Superfund Research Program, which is funded by the National Institute of Environmental Health Sciences. He noted, however, that infant formulas containing added rice starch did not appear to be a concern in terms of elevated arsenic.
Jackson also pointed out that brown rice syrup is likely to have higher arsenic concentrations than other sweeteners whether the rice is grown organically or not. “That’s because the rice takes up natural arsenic from the soil and when the rice is used to make brown rice syrup, much of that arsenic ends up there,” he said. “We focused on organic brown rice syrup because this seems to be a sweetener of choice for some organic food products.”
Among advice Jackson provided when we asked him what consumers currently can do to limit their dietary exposure to arsenic via rice in products Dartmouth researchers have tested:
Individuals who consume a lot of rice, including those on gluten-free diets, should try to add variety to their diets and check ingredient labels, as many gluten-free foods are rice-based.
As the new research showed, parents can reduce young children’s dietary arsenic exposure by limiting their consumption of formula in which organic brown rice syrup is a main ingredient. Another study by Dartmouth researchers published online in January 2012 found that total arsenic in some rice-fortified baby foods, such as jars containing meat-rice combinations, as well as fruit and vegetable purees for babies, ranged from less than 1 ppb up to 22 ppb, the majority of which was the carcinogenic form.
Eating an occasional cereal bar does not pose much risk, but the latest study’s results add to the increasing recognition that food is a significant, or in many cases, the main arsenic exposure route for people. Therefore it’s wise to limit daily consumption of foods known to contain arsenic, keeping in mind that even seemingly small exposures from juices, rice or rice-fortified foods add up.