“It’s almost either-or, day-and-night as to whether we see arsenic or cadmium in the rice,” said Dr. Guerinot, a molecular geneticist and professor of biology at Dartmouth College.
The levels of arsenic and cadmium at the study site are not high enough to provoke alarm, she emphasized. Still, it is dawning on scientists like her that rice, one of the most widely consumed foods in the world, is also one of nature’s great scavengers of metallic compounds.
Consumers have already become alarmed over reports of rice-borne arsenic in everything from cereal bars to baby food. Some food manufacturers have stepped up screening for arsenic in their products, and agencies such as the Food and Drug Administration now recommend that people eat a variety of grains to “minimize potential adverse health consequences from eating an excess of any one food.”
But it’s not just arsenic and cadmium, which are present in soil both as naturally occurring elements and as industrial byproducts. Recent studies have shown that rice is custom-built to pull a number of metals from the soil, among them mercury and even tungsten. The findings have led to a new push by scientists and growers to make the grain less susceptible to metal contamination.
The highest levels often occur in brown rice, because elements like arsenic accumulate in bran and husk, which are polished off in the processing of white rice. The Department of Agriculture estimates that on average arsenic levels are 10 times as high in rice bran as in polished rice.
Although these are mostly tiny amounts — in the part per billion range — chronic exposure to arsenic, even at very low levels, can affect health. The F.D.A. is now considering whether a safety level should be set for arsenic in rice.
- More Here
The levels of arsenic and cadmium at the study site are not high enough to provoke alarm, she emphasized. Still, it is dawning on scientists like her that rice, one of the most widely consumed foods in the world, is also one of nature’s great scavengers of metallic compounds.
Consumers have already become alarmed over reports of rice-borne arsenic in everything from cereal bars to baby food. Some food manufacturers have stepped up screening for arsenic in their products, and agencies such as the Food and Drug Administration now recommend that people eat a variety of grains to “minimize potential adverse health consequences from eating an excess of any one food.”
But it’s not just arsenic and cadmium, which are present in soil both as naturally occurring elements and as industrial byproducts. Recent studies have shown that rice is custom-built to pull a number of metals from the soil, among them mercury and even tungsten. The findings have led to a new push by scientists and growers to make the grain less susceptible to metal contamination.
The highest levels often occur in brown rice, because elements like arsenic accumulate in bran and husk, which are polished off in the processing of white rice. The Department of Agriculture estimates that on average arsenic levels are 10 times as high in rice bran as in polished rice.
Although these are mostly tiny amounts — in the part per billion range — chronic exposure to arsenic, even at very low levels, can affect health. The F.D.A. is now considering whether a safety level should be set for arsenic in rice.
- More Here
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