Responding to a study that detected "significant" levels of arsenic in common rice products, consumer advocates today urged the Food and Drug Administration to set standards for the human carcinogen in rice.

Consumer Reports said it found inorganic arsenic, a carcinogen, in cereals, rice breakfast products, brown rice and white rice -- including organic versions. The group tested 200 rice products after a January investigation detected the substance in juices purchased on the East Coast.

"The results of our tests were even more troubling in some ways than our findings for juice," Consumer Reports said today on its website. "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."

There is currently no standard for arsenic in food, though U.S. EPA has said there is no safe level of exposure to inorganic arsenic. For drinking water, the standard is 10 parts per billion.

EPA originally proposed a 5 ppb standard that the state of New Jersey eventually established. Consumer Reports concluded that, using the 5 ppb standard, "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."

The group highlighted levels of inorganic arsenic in some infant rice cereals that were "at least five times" what was found in alternatives like oatmeal.

The rice industry has maintained that its products are safe and that there is no evidence of harmful health effects associated with rice consumption. The USA Rice Federation also emphasized that arsenic is naturally occurring in air, water, rocks and soil.

"We are aware of concerns about the level of arsenic in food," the trade association said in a statement, "but are not aware of any established studies directly connecting rice consumption and adverse health effects. In fact, populations with high rice consumption are associated with less overall disease rates and with better health, and scientific studies show that people who eat rice have healthier diets."

The group also said it is "disappointed" with the Consumer Reports study, claiming that it uses inaccurate methodologies and fails to take into account rice's health benefits.

FDA, however, acknowledged that there is significant consumer concern about the issue. The agency released a statement today saying it has begun an analysis of about 1,200 samples, releasing information on 200 of those samples today.

Still, FDA said it does not have an "adequate scientific basis" to recommend that consumers change their eating habits.

"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," FDA Commissioner Margaret Hamburg said in the statement.

FDA expects to complete its review by the end of the year. In the meantime, said FDA Deputy Commissioner Michael Taylor, "it is critical to not get ahead of the science."

But public health advocates say the Consumer Reports study underscores the government's lack of action.

"Over the past two decades, EPA has invested millions of dollars in reducing exposure to arsenic in drinking water," said Sonya Lunder, senior research analyst at the Environmental Working Group. "During that same period, FDA has done almost nothing to address arsenic in our diets."

Lunder reiterated the call from Consumer Reports for FDA to set standards.

"In many cases arsenic in rice comes from natural sources, but that doesn't mean it is safe," she said. "Arsenic is a human carcinogen, and FDA needs to do everything possible to reduce exposures from our food."