As you may be aware, researchers at Dartmouth published a paper on arsenic levels in rice products earlier this year. Recently, Consumer Reports published an article in which they looked at the same issue. Both found some fairly high levels in a range of products, so there has quite understandably been a fair amount of media attention and public concern.
There are several factors that make this a rather complicated issue. The first is that while the EPA has set the arsenic standard for drinking water at 10 parts per billion, no government agency has established safety thresholds for arsenic in food. There seems to be a growing consensus among researchers and regulators that we need some sort of safety threshold for food, but I expect that to be a few years away yet. Secondly, there are two basic forms of arsenic, organic and inorganic (which have no relationship to organic food or agriculture), which seem to have different effects on human health — in general inorganic arsenic seems to be more problematic, although many scientists seem to think organic arsenic deserves greater scrutiny as well. Thirdly, many plants selectively accumulate particular minerals into their tissues, a process referred to as bioaccumulation. Unfortunately, rice seems to bioaccumulate arsenic, so if there is arsenic in the soil, whether from natural or artificial sources, it will end up in higher concentrations in rice than in other crops. Other factors, including flooding of rice paddies, also make rice more likely than many other crops to concentrate arsenic in their tissues.
Generally speaking, both total arsenic levels and inorganic arsenic levels are generally lower in organic rice, and as far as domestic crops are concerned, it seems that California rice has lower levels of arsenic than that grown in the Southeast (Arkansas, Georgia, etc). Processed foods made from rice, such as brown rice syrup (including organic) and pasta, generally have levels above plain rice.
All rice that has been tested has shown some level of arsenic. There is at this point no “arsenic free” or “low arsenic” certification for rice, nor is there any scientific or governmental consensus as to what amount, if any, of arsenic in food represents a safe level. However, of the tests that I have seen, Lundberg brand rices test fairly low on the spectrum. Lundberg produces organic and non-organic “eco-farmed” rice, and makes up a large percentage of the rice we sell on our grocery shelves and in our bulk bins.
Current recommendations are to maintain a varied diet, and avoid letting any one food item dominate. Infants, pregnant women, and nursing mothers should take special care to avoid arsenic exposure, possibly including reducing the amount of rice in their diet.
If you’d like more information, you may be interested in the following links: