The Food and Drug Administration is conducting an in-depth investigation of arsenic levels in rice.
Today's release of initial information from the investigation coincides with a new study from Consumer Reports that recommends limiting consumption of rice products. Consumer Reports expressed concerns last year regarding arsenic levels in juice and rice-based baby foods.
The FDA says it does not have enough information yet to make any recommendations on whether consumers should change their diets to curb rice consumption. For now, the agency recommends people vary their diet.
"Our advice right now is that consumers should continue to eat a balanced diet that includes a wide variety of grains — not only for good nutrition but also to minimize any potential consequences from consuming any one particular food," said Dr. Margaret Hamburg, FDA commissioner.
There are two types of arsenic: organic and inorganic. Arsenic occurs naturally in the environment, and can also be present as the result of human activity, such as the use of arsenic-containing pesticides. [See 5 Things You Should Know About Arsenic]
Inorganic arsenic is a known carcinogen, and chronic exposure to low levels has been linked to increased risks of bladder, lung and skin cancer, as well as Type 2 diabetes and cardiovascular disease. While the Environmental Protection Agency has set a limit on the amount of arsenic that can be present in water (10 parts per billion), no limit has been set for food.
So far, the FDA has analyzed samples of 200 U.S. rice and rice products, and plans to analyze 1,000 more.
The preliminary analysis includes information about inorganic arsenic levels in various brands of rice, Basmati rice, brown rice, rice cereals (puffed, non-puffed, hot cereal and infant cereals), rice cakes and rice milk, the FDA says.
The results show the average levels of inorganic arsenic in the products vary from 3.5 to 6.7 micrograms per serving. The highest levels of inorganic arsenic were found in a sample of long-grain brown rice, at 10.5 micrograms per severing.
Gathering initial data is a first step in an ongoing analysis, the FDA says.
"It is critical to not get ahead of the science," said Michael Taylor, the FDA deputy commissioner for foods. "The FDA's ongoing data collection and other assessments will give us a solid scientific basis for determining what action levels and/or other steps are needed to reduce exposure to arsenic in rice and rice products."
A study published last year found people who eat more rice have higher levels of arsenic in their systems. In that study, consuming just over one-half of a cup of cooked rice is equivalent to drinking 34 ounces (one liter) of water containing the maximum amount of arsenic allowed by the federal limit.
Just how much rice you'd need to consume for it to affect your health is unknown. But roughly, it's thought that 10 grams of arsenic over a lifetime would increase the risk of diseases such as cancer, Christopher States, a toxicologist at the University of Louisville in Kentucky, told MyHealthNewsDaily in an interview last year. Because levels of arsenic in rice are on the order of one-millionth of a gram, a person would have to eat "a ton" of rice to get to this amount, States said.
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