The
Great Rice Debate
From: Paul Icamina
on ENN.com, Science and Development Network, More from this Affiliate
Following alarming reports
from the United States about the discovery of high arsenic levels in rice sold
in the US market, experts from the International Rice Research Institute (IRRI)
in the Philippines have reassured consumers that rice is safe to eat.
In a statement released
to SciDev.Net, IRRI said that "that there is no evidence to show that
people should stop eating rice grown in Asia because of concerns about
arsenic." But it stopped short of denying claims that arsenic was present
in rice.
The preliminary results
of a study of 200 rice samples, published by the US Food and Drug
Administration (FDA) last week (19 September), showed that sampled rice
contained average levels of 3.5 to 6.7 micrograms of inorganic arsenic per
average serving.
Separately, Consumer
Reports — a marketplace standards nongovernmental organisation that earlier
pressured the FDA to define standards for arsenic in apple juice — announced on
18 September that it had found arsenic levels in rice of up to 8.7 micrograms
per average serving.
It is difficult to tell
at what point arsenic levels in rice become dangerous, as, while there is an
official standard for water, there is none for food.
Currently China is the
only country to have set arsenic limits on food, said Joy Duldulao, a senior
researcher at PhilRice (the Philippine Rice Research Institute).
The FDA plans to assess
legal standards for arsenic levels in rice at the end of the year, once they
have analysed 2,300 rice samples.
Safety levels vary
according to how much rice an individual consumes, Duldulao added. However,
citing data from the UN Food and Agriculture Organization, she said the
tolerable weekly intake is only 15 micrograms of inorganic arsenic per kilogram
of body weight.
Consumer Reports warned
that eating rice high in arsenic just once a day can drive arsenic levels in
the human body up by 44 per cent, while two meals could boost levels to 70 per
cent.
Arsenic is a naturally
occurring substance found in water, air and soil. However, in high quantities
it is also a potent poison linked to bladder and kidney cancer. It is absorbed
by all plants, although concentrations are higher in leafy vegetables, apples
and rice.
Rice is believed to have
higher arsenic levels than other plants because it is grown in flooded soils,
thus optimising conditions for the absorption of arsenic.
