As arsenic occurs in soil, water, and air, the United States Food and Drug Administration (FDA) monitors the levels of arsenic in foods, particularly in rice products used commonly for infant food. While growing, rice plants tend to absorb arsenic more readily than other food crops, requiring expanded testing by the FDA for possible arsenic-related risks associated with rice consumption in the United States. In April 2016, the FDA proposed a limit of 100 parts per billion (ppb) for inorganic arsenic in infant rice cereal and other foods to minimize exposure of infants to arsenic. For water contamination by arsenic, the United States Environmental Protection Agency has set a lower standard of 10 ppb.
Arsenic is a Group 1 carcinogen. The amount of arsenic in rice varies widely with the greatest concentration in brown rice and rice grown on land formerly used to grow cotton, such as in Arkansas, Louisiana, Missouri, and Texas. White rice grown in Arkansas, Louisiana, Missouri, and Texas, which account collectively for 76 percent of American-produced rice, had higher levels of arsenic than other regions of the world studied, possibly because of past use of arsenic-based pesticides to control cotton weevils. Jasmine rice from Thailand and Basmati rice from Pakistan and India contain the least arsenic among rice varieties in one study. China has set a limit of 150 ppb for arsenic in rice.
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