Feb. 16, 2012 -- Organic brown rice syrup, a popular sweetener in organic and gluten-free foods -- including some formulas made for toddlers -- is a source of the toxin arsenic, a new study shows.
Experts say regularly eating foods that use organic brown rice syrup as a main ingredient could expose a person to more arsenic than the government allows in drinking water, raising the risks for cancer and heart disease. In young children, chronic arsenic exposure has been linked to lower IQs and poorer intellectual function.
“This seems to be quite strong evidence,” says Ana Navas-Acien, MD, PhD, an assistant professor of environmental health sciences and epidemiology at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Md.
“I would personally not buy formula made of brown rice,” says Navas-Acien, who studies the health effects of arsenic exposure. She was not involved in the current research.
Manufacturers insist that their products are safe.
Rice Products Are on FDA's Radar
It’s not the first time arsenic has turned up in rice-based foods for infants and toddlers. Last year, researchers in Sweden reported finding elevated levels of arsenic and other heavy metals in rice cereals, which parents often use to transition children to solid foods.
Because babies and toddlers are smaller than adults, they get a bigger exposure (based on body weight) of arsenic from a given serving of food than an adult would. And their developing organs may be especially sensitive to environmental exposures.
Regulatory agencies in Europe and the U.K. are in the midst of setting new limits for arsenic in foods, particularly foods made for young children.
In the U.S., there are no set standards for arsenic in food. The FDA is weighing a limit for arsenic in fruit juice after recent tests turned up high levels in some brands of apple juice.
The FDA says rice products are also on its radar. The agency confirms that it has recently tested rice products for arsenic. The results of those tests are pending.
Researchers say they are glad the FDA is stepping up its scrutiny of arsenic in foods.
“We need to elevate the discussion about whether we do need regulations and guidelines for arsenic in food,” says researcher Brian P. Jackson, PhD, director of trace metal analysis at Dartmouth College in Hanover, N.H. “And rice-based foods would be the first foods we should look at, I think.”
Rice growers disagree that their products should be singled out.
“U.S. rice and rice products are safe to consume,” says Stacy Fitzgerald-Redd, a spokesperson for the USA Rice Federation. “When discussing the content of arsenic in foods it is essential to distinguish between organic and inorganic arsenic,” she tells WebMD.
“Most of the arsenic found in rice is organic arsenic, the benign kind, and the U.S. rice industry is working with U.S. regulatory officials as they look into this issue,” she says.
“There has been no documented incident where ingestion of rice or rice products has led to human health problems, and the U.S. rice industry is committed to maintaining the safety of U.S. rice and rice products,” the statement says.
Arsenic in Foods Made With Brown Rice Syrup
For the study, which is published in the journal Environmental Health Perspectives, researchers analyzed arsenic levels in 17 different brands of formula made for infants and toddlers.
They also tested 29 energy bars, and three energy gels, portable sources of easily digested carbohydrates often used by endurance athletes.
And they checked three organic brown rice syrups, which are sold in the natural or organic sections of some supermarkets. Some people use rice syrup as an alternative to sugar or corn syrup in baked goods and beverages.
Products that didn’t list rice or rice syrups as top ingredients were all low in arsenic.
But the rice syrups themselves, and products that listed rice syrups or rice as one of the first five ingredients, all had high arsenic levels.
Most of the arsenic detected in the bars and energy gels was inorganic arsenic, the kind that’s believed to be the most toxic.
Still, that may not be so concerning, experts say, for foods that are eaten only occasionally. The body can typically clear a single small dose of arsenic in just a few days.
But for food staples, the danger increases.
Arsenic in Baby Formula
Two kinds of organic formula that listed brown rice syrup as their first ingredient, for example, had arsenic levels that were two to five times higher than the limits allowed in drinking water.
“The infant formula is really troubling, concerning,” says Michael Bloom, PhD, an assistant professor in the department of environmental health sciences at the University of Albany, State University of New York, in Rensselaer.
“These children who are fed with formula almost exclusively are getting a very high relative dose of arsenic from these sources,” says Bloom, who studies the health effects of arsenic exposure, but was not involved in the research.
In three of the samples, most of the arsenic that was detected was organic, which has been thought to be less harmful than inorganic arsenic.
But experts say new evidence suggests that the kind of organic arsenic picked up in the study, DMA, is not risk-free.
“The available evidence suggests that it is toxic, too,” says Navas-Acien.
The arsenic levels detected in the formula were still too low to cause immediate illness.
But over the longer term, studies have shown that young children exposed to moderate arsenic levels, over 50 micrograms per liter, are more likely to have lower IQs and reduced brain function compared to kids drinking water with arsenic levels below 5.5 micrograms per liter.
For comparison, three samples of the formula made with brown rice syrup in the study had about 30 micrograms of arsenic per liter. The fourth sample had nearly 60 micrograms of arsenic per liter.
The U.S. EPA says drinking water shouldn’t contain more than 10 micrograms per liter.
How Arsenic Gets Into Rice
Arsenic is a colorless, tasteless substance that’s naturally present in the environment. It’s also used as a fertilizer and wood preservative. Once in the soil, it can persist for years. It easily dissolves in water.
According to a previous WebMD interview with John M. Duxbury, PhD, a professor of soil science and international agriculture at Cornell University in Ithaca, N.Y., rice is particularly vulnerable to arsenic contamination because it grows in water.
Because arsenic is stored in the darker outer layers of the rice grain, called the germ, brown rice contains higher levels of arsenic than white rice.
Long-term exposure to arsenic, typically from drinking well water, has been linked to cancers of the bladder, liver, kidney, skin, prostate, and lungs. Recent research has also tied chronic arsenic exposure to an increased risk for heart disease. Jackson says more research is needed to understand how arsenic in foods may contribute to those health risks.
For babies, arsenic is another reason why breast milk may be the healthiest option.
“Breast milk has very little arsenic in it, even if the mother is exposed to a lot of arsenic. It doesn’t travel through the mammary glands,” Bloom says.