A new study suggests that pregnant women in the US should be mindful of their rice consumption after researchers found that the food staple may be a significant source of arsenic and could lead to harmful exposure for the baby.
While arsenic exposure through contaminated drinking water is well-documented, new data has been emerging on the dietary intake of arsenic, researchers wrote in their study, published online this week in the Proceedings of the National Academy of Sciences.
When it comes to dietary intake, rice in particular has been singled out as a major method of exposure for the way it's grown in paddy fields and the food's physiology.
Meanwhile, after measuring the arsenic levels in the urine of 229 pregnant women in the state of New Hampshire, researchers found that women who said they had recently consumed rice had elevated levels of inorganic -- or toxic -- arsenic in their urine.
Furthermore, eating half a cup of cooked rice a day was akin to drinking one liter of water that contained the maximum allowable limit of arsenic in the US, researchers found.
Rice consumption in the US averages half a cup a day, while that number rises with Asian Americans who eat more than two cups daily.
If elevated arsenic levels in rice prove to be a dietary hazard, some groups will be harder hit than others.
In a 2009 study of an American Korean community, for example, participants reported consuming about three cups of cooked rice a day. In parallel, the subjects also had a urinary arsenic concentration that was three times the national average.
About three million Americans also live with celiac disease, an autoimmune disorder triggered by gluten intolerances, the study says. And one of the most common substitutes for wheat products is rice-based ingredients.
While arsenic exposure in fetal development is not yet well understood, inorganic arsenic is a human carcinogen that's been linked to bladder, lung, and skin cancer and immunodeficiencies.
Warnings about food and arsenic have been gaining headlines recently, as the rice study follows closely on the heels of controversial reports that found elevated traces of the heavy metal in children's apple and grape juice.
Earlier this fall, Dr. Mehmet Oz, host of US talk show The Dr. Oz Show, caused a stir with claims that commercial grocery store apple juice brands contained high levels of arsenic.
The FDA responded by conducting its own study, which found only trace amounts of inorganic or poisonous arsenic in its samples.