A sampling of products sweetened with organic brown rice syrup, including cereal bars and baby formulas , found levels of arsenic that exceeded US standards for bottled water, US researchers said.

The study by researchers at Dartmouth College in New Hampshire followed a Consumer Reports analysis of arsenic levels in some fruit juices last year. The previous study showed some juice samples exceeded federal limits on arsenic in place for drinking water, prompting concern from consumer groups and US lawmakers.

Organic brown rice syrup is used as a sweetener in some food products as an alternative to high fructose corn syrup, researchers said, and rice can be a major source of inorganic arsenic.

For the latest study, the team tested 17 baby formulas , 29 cereal bars and three energy shots that were purchased in the Hanover, New Hampshire area.

Of the two formulas that listed organic brown rice syrup as the main ingredient, one had a total arsenic concentration that was six times the federal limit for bottled water, which is 10 parts per billion, the team reported in the journal Environmental Health Perspectives.

"I don't think there's much risk associated with eating a cereal bar every couple of days," Brian Jackson, the lead researcher, told Reuters. "But it is a source of arsenic that we may not be considering."

For babies and toddlers, Jackson said it would be best to avoid formulas that use organic brown rice syrup as a sweetener until arsenic levels in such products are regulated.

Arsenic is toxic at high doses, and chronic exposures can damage the liver, skin, kidney and cardiovascular system. Babies are especially vulnerable because of their size, the team said.

A Web-based search found that only the two formulas studied contained organic brown rice syrup, so the number of infants exposed is "presumably a very low percentage of US formula-fed infants," the team wrote. The researchers did not identify the brands of the products that were tested.

The researchers studied 29 cereal bars and high energy bars and found 22 listed rice-based ingredients -- including organic brown rice syrup, rice flour, rice grain or rice flakes - among the top five ingredients.

Tests of these bars showed they had higher arsenic concentrations than comparable food products without the rice-based sweetener.

The team said arsenic and arsenic metabolites can become absorbed in rice through natural microbes and traces of pesticides in the soil.

Since there are no US regulations governing arsenic in food, the team said the findings showed there was an "urgent need" for regulation.  - Reuters