Arsenic In Your Food Investigated - Consumer Reports (2024)

Organic rice baby cereal, rice breakfast cereals, brown rice, white rice—new tests by Consumer Reports have found that those and other types of rice products on grocery shelves contain arsenic, many at worrisome levels.

Arsenic not only is a potent human carcinogen but also can set up children for other health problems in later life.

Following our January investigation, "Arsenic in Your Juice," which found arsenic in apple and grape juices, we recently tested more than 200 samples of a host of rice products. They included iconic labels and store brands, organic products and conventional ones; some were aimed at the booming gluten-free market.

The results of our tests were even more troubling in some ways than our findings for juice. In virtually every product tested, we found measurable amounts of total arsenic in its two forms. We found significant levels of inorganic arsenic, which is a carcinogen, in almost every product category, along with organic arsenic, which is less toxic but still of concern. Moreover, the foods we checked are popular staples, eaten by adults and children alike. See the chart summarizing results of our tests for arsenic in rice or rice products.

Though rice isn't the only dietary source of arsenic—some vegetables, fruits, and even water can harbor it—the Environmental Protection Agency assumes there is actually no "safe" level of exposure to inorganic arsenic.

No federal limit exists for arsenic in most foods, but the standard for drinking water is 10 parts per billion (ppb). Keep in mind: That level is twice the 5 ppb that the EPA originally proposed and that New Jersey actually established. Using the 5-ppb standard in our study, we found that a single serving of some rices could give an average adult almost one and a half times the inorganic arsenic he or she would get from a whole day's consumption of water, about 1 liter.

We also discovered that some infant rice cereals, which are often a baby's first solid food, had levels of inorganic arsenic at least five times more than has been found in alternatives such as oatmeal. Given our findings, we suggest limiting the consumption of rice products. Use our recommendations.

Our study was a snapshot of the market, with many products purchased in the New York metropolitan area and online, to gauge the extent of arsenic's presence in everyday foods. It can't be used for overall conclusions about specific brands. Still, we found important trends:

Studies show that arsenic can cause cancer in humans.

Rice producers argue that concerns about dietary exposure to arsenic in rice are overblown. "There is no documented evidence of actual adverse health effects from exposure to arsenic in U.S.-grown rice," says Anne Banville, a vice president at the USA Rice Federation, a trade association representing the $34 billion rice industry. "And we believe the health benefits of rice must be properly weighed against the risks of arsenic exposure, which we believe are minimal."

But scientists warn of complacency. "We already know that high concentrations of arsenic in drinking water result in the highest known toxic substance disease risks from any environmental exposure," says Allan Smith, M.D., Ph.D., a professor of epidemiology at the University of California, Berkeley. "So we should not be arguing to wait for years until we have results of epidemiologic studies at lower arsenic intake, such as from rice consumption, to take action." His studies of arsenic in public water in Chile and Argentina helped show that it causes lung and bladder cancer and other diseases.

Such long-term studies that track health effects of exposure to arsenic in rice have only recently begun in the U.S. Researchers at the Dartmouth Children's Environmental Health and Disease Prevention Research Center in late 2011 published a small but informative study that indicated consuming slightly more than a half-cup of cooked rice per day resulted in a significant increase in urinary arsenic levels, comparable to the effects of drinking a liter of water containing the federal maximum of 10 ppb arsenic. The authors say their results suggest "many people in the U.S. may be exposed to potentially harmful levels of arsenic through rice consumption."

The USA Rice Federation says it is working with the FDA and the EPA as they examine and assess arsenic levels in food and has supplied rice samples to those agencies for research. It also says some of its member companies may be doing their own testing. One rice company shared with us details of how it is taking matters into its own hands. Grant Lundberg, CEO of Lundberg Family Farms in Richvale, Calif., which sells rice and rice products, says the company is testing more than 200 samples of the many varieties of rice in its supply chain and plans to share the results with FDA scientists.

"We're committed to providing safe food, to really listening to our consumers, and dealing with this problem very openly because doing the research needed to assess what the risks really are is the only way to go," Lundberg says.

The USA Rice Federation tells consumers that there is no reason to be concerned about arsenic in food. Its website states that arsenic is "a naturally occurring element in soil and water" and "all plants take up arsenic."

But "natural" does not equal safe. Inorganic arsenic, the predominant form of arsenic in most of the 65 rice products we analyzed, is ranked by the International Agency for Research on Cancer (IARC) as one of more than 100 substances that are Group 1 carcinogens. It is known to cause bladder, lung, and skin cancer in humans, with the liver, kidney, and prostate now considered potential targets of arsenic-induced cancers.

Though arsenic can enter soil or water due to weathering of arsenic-containing minerals in the earth, humans are more to blame than Mother Nature for arsenic contamination in the U.S. today, according to the federal Agency for Toxic Substances and Disease Registry. The U.S. is the world's leading user of arsenic, and since 1910 about 1.6 million tons have been used for agricultural and industrial purposes, about half of it only since the mid-1960s. Residues from the decades of use of lead-arsenate insecticides linger in agricultural soil today, even though their use was banned in the 1980s. Other arsenical ingredients in animal feed to prevent disease and promote growth are still permitted. Moreover, fertilizer made from poultry waste can contaminate crops with inorganic arsenic.

Rice is not the only source of arsenic in food. A 2009-10 study from the EPA estimated that rice contributes 17 percent of dietary exposure to inorganic arsenic, which would put it in third place, behind fruits and fruit juices at 18 percent, and vegetables at 24 percent. A more complete study by the European Food Safety Authority found cereal products could account for more than half of dietary exposure to inorganic arsenic, mainly because of rice.

Rice absorbs arsenic from soil or water much more effectively than most plants. That's in part because it is one of the only major crops grown in water-flooded conditions, which allow arsenic to be more easily taken up by its roots and stored in the grains. In the U.S. as of 2010, about 15 percent of rice acreage was in California, 49 percent in Arkansas, and the remainder in Louisiana, Mississippi, Missouri, and Texas. That south-central region of the country has a long history of producing cotton, a crop that was heavily treated with arsenical pesticides for decades in part to combat the boll weevil beetle.

"Extensive surveys of south central U.S. rice, by more than one research group, have consistently shown that rice from this region is elevated in inorganic arsenic compared to other rice-producing regions," says Andrew Meharg, professor of biogeochemistry at the University of Aberdeen in Scotland and co-author of the book "Arsenic & Rice." "And it does not matter relative to risk whether that arsenic comes from pesticides or is naturally occurring." High levels of arsenic in soil can actually reduce rice yields. Meharg, a leading researcher in the field, notes the Department of Agriculture has invested in research to breed types of rice that can withstand arsenic. That may help explain the relatively high levels of arsenic found in rice from the region, though other factors such as climate or geology may also play a role.

If rice truly is an important source of arsenic exposure, then people who eat rice should have greater arsenic levels in their body, on average, than people who do not. To find out, we analyzed data collected annually by the National Center for Health Statistics for the National Health and Nutrition Examination Survey (NHANES). The survey contains information on the health and nutrition of a nationally representative sample of the U.S. population, based on interviews and physical exams, which may include blood and urine tests.

Our data analysis was led by Richard Stahlhut, M.D., M.P.H., an environmental health researcher at the University of Rochester, who is experienced in NHANES analysis, and Ana Navas-Acien, M.D., Ph.D., a physician-epidemiologist with expertise in arsenic research at Johns Hopkins University's Bloomberg School of Public Health. Working with Consumer Reports statisticians, they reviewed NHANES data from 2003 through 2010 from participants age 6 or older whose urine was tested for arsenic and who had reported what they'd had to eat or drink from midnight to midnight the day before their examination. A urine test is the best measure of recent arsenic exposure because most of it is excreted in urine within a few days after ingestion.

Our study shows people who eat rice have higher arsenic levels.

Because seafood contains a form of organic arsenic called arsenobetaine, generally considered nontoxic to humans, we then excluded from our analysis anyone who reported eating seafood during the 24-hour period and those with detectable levels of arsenobetaine in their urine. The remaining participants therefore were more likely to have had exposure to inorganic arsenic, which poses the greatest potential health risks.

Our resulting analysis of 3,633 study participants found that on average, people who reported eating one rice food item had total urinary arsenic levels 44 percent greater than those who had not, and people who reported consuming two or more rice products had levels 70 percent higher than those who had no rice.

"Despite our taking into account other common sources of arsenic, and no matter which way we sliced the data, we see a very strong association between rice consumption and arsenic exposure," says Stahlhut, who along with Navas-Acien led a similar analysis of NHANES data for our January 2012 article on arsenic in juice. That analysis found that study participants who reported drinking apple or grape juice had total urinary arsenic levels that were on average nearly 20 percent higher than those who didn't. Consumers Union, the advocacy arm of Consumer Reports, urged the FDA to set a 3 ppb limit for total arsenic in apple and grape juice.

"These findings show that rice is an important source of arsenic exposure for the U.S. population," says Navas-Acien. The associations were even stronger for rice compared with juice and are consistent with the relatively high levels of arsenic, including inorganic arsenic, measured in rice samples, she says. She says the results underscore the need for monitoring arsenic in food and establishing safety standards. A new study of NHANES data from Dartmouth researchers also shows that rice consumption can contribute to increased urinary arsenic levels in children.