Are there particular foods that it’s in? continued...
But because we eat a much lower volume of leafy greens compared to other kinds of foods,
“arsenic intake from this source is also low,” Duxbury says.
Rice appears to be particularly vulnerable to arsenic contamination because it grows in water.
Arsenic dissolves easily in water. So drinking water has long been monitored as a source of exposure to arsenic.
Because rice is grown in paddies, which are flooded with water, it can be exposed to higher amounts of arsenic than plants grown in drier soils, Duxbury says.
Tracy Punshon, PhD, a research assistant professor at Dartmouth College in Hanover, N.H., has X-rayed rice grains to see where they store arsenic.
She found that arsenic concentrates in the part of the grain called the germ, which is removed to make white rice. That means brown rice has higher concentrations of arsenic that white rice.
Studies by Scottish researchers have found higher levels of arsenic in rice grown in the U.S. than in basmati or jasmine rice from Thailand or India.
The highest levels of arsenic in U.S.-grown rice came from Southern states. The lowest levels were detected in rice grown in California.
What are the potential health consequences?
At very high levels, arsenic can be fatal. At lower levels, arsenic can cause nausea and vomiting and decrease the amount of red and white blood cells produced by the body. It also causes abnormal heart rhythms, may damage blood vessels, and causes a pins and needles sensation in the hands and feet.
However, far less is understood about what happens to people when they are exposed to low levels of arsenic over a long period of time.
“This is a relatively new area of research,” says arsenic expert Ana Navas-Acien, MD, PhD.
It’s clear that arsenic is associated with higher rates of skin, bladder, and lung cancers, says Navas-Acien, an assistant professor of environmental health sciences and epidemiology at Johns Hopkins Bloomberg School of Public Health in Baltimore.