Friday 2 October 2015

Arsenic Levels in Foods

Arsenic is naturally present in the environment, which means it gets into food and water with levels varying in different regions of the world. It’s impossible to eliminate it from food, however, having too much arsenic in our diet could be harmful to health. Rice tends to take up more arsenic from the environment than other cereal crops, although this can vary according to variety and method of production. The arsenic in rice also tends to be predominately the more toxic inorganic form, which has the potential to increase risk of illnesses including cancer. Recent interest following a televised documentary programme on the risks of eating rice has brought this old topic back into the spotlight once again.
There really is arsenic in lots of food. In fact, the proposed new limits from the EU (200 parts per billion in food for adults, and 100 parts per billion in food for children and babies) are supported by the UK Food Standards Agency (FSA). Arsenic occurs naturally in rocks, and there's some lying around in the earth from the days when arsenic-containing pesticides were used. It dissolves easily in water, and is absorbed from water and from the soil by plants. It's found in fruit, vegetables and grains. On the whole, levels in grains tend to be lower than in plant leaves, but we don't eat as much plant leaf as we do rice. And rice is particularly efficient at picking up arsenic compared to other grains. What's more, because the arsenic gets in from soil and water, rather than from insecticides used today, organic products are just as high in arsenic as non-organic ones.

As a nation, we eat four times more rice than we did 40 years ago, and rice cakes and baby rice are very widely used as early foods for babies. So these new guidelines probably have more to do with a realisation that even tiny amounts of arsenic can add up in the long term, rather than a sudden increase in the levels of arsenic in rice. It's always been there, but we've only just noticed.
While every doctor knows the risks of serious alcohol poisoning (diarrhoea and vomiting, abdominal cramps, heart problems, dehydration, collapse and sometimes death), far less is known about the long-term effects of exposure to lower levels of arsenic. It has been linked with a possible increased risk of cancer, including bladder, skin, kidney and lung. It may also be a risk factor for heart attack and stroke. In pregnancy, there may be a link with miscarriage and low birth-weight babies, and in kids it may have an effect on brain development.

What we don't know is the level at which risks start to rise. We're never going to remove all the arsenic from the soil or from food - just like we're never going to remove all the radiation in the world we live in. We certainly don't have to ban rice from our tables immediately for fear of collapsing, frothing at the mouth. In fact, there's absolutely no need to do anything if your rice intake is limited to a few meals a week.

So what is being done to tackle this issue?
The FSA is contributing to discussions in Europe to set limits for inorganic arsenic in rice and rice products. The limits are close to being agreed. There are international efforts to better understand this and develop of code of practice that can be employed by producing countries to mitigate levels of arsenic in rice.
  • The FSA supports setting EU maximum limits for inorganic arsenic in rice and rice products. We now have systems available in official labs which will mean that products can be checked to ensure they meet the rules.
  • The FSA is working hard in Europe to ensure that effective, proportionate and enforceable EU maximum limits for arsenic in rice are agreed as soon as possible; that more stringent limits are put in place for rice and rice products for infants and young children; and that these will be subject to regular review. The limits are close to being agreed, and we expect them to apply from mid-next year.
  • EU maximum limits for environmental contaminants are reviewed on a regular basis and are subject to future revision to take account of the latest evidence and data – therefore there may be scope to reduce them further in due course.
  • It is the responsibility of manufacturers to ensure that the food they produce is as low as reasonably achievable in regard to arsenic. This will still be the case once maximum limits are in place.
  • The Codex (Alimentarius) Committee on Contaminants in Food is compiling a Code of Practice for the Prevention and Reduction of Arsenic Contamination in Rice, for rice producers to use to control levels. The FSA has ensured that experts have an opportunity to influence the drafting of this document.
  • The FSA is carrying out a survey on infant foods, and this will include looking at the exposure of infants to rice products and arsenic. It’s likely to be published in the new year, and the FSA will consider whether the results indicate any further risk management action is required to compliment the EU maximum limits.
Advice on the consumption of rice drinks
The FSA advise that toddlers and young children (ages 1 - 4.5 years) should not be given rice drinks as a substitute for breast milk, infant formula or cows’ milk. This is because of their proportionally higher milk consumption and lower bodyweights compared to other consumers. There are a number of alternatives to suit those with an allergy or intolerance to cows’ milk or soya. Advice should be sought from a health professional (such as a doctor or dietician) to ensure a suitable milk alternative is sought for a healthy and balanced diet.


Brown rice: Not a health food!
Brown rice, on the other hand, has significantly more arsenic than white rice and should be avoided or consumed rarely. Some of the brown rice brands tested contained at least 50% more than the safe limit per serving, and a few even had nearly double the safe limit. Note that some of the worst offenders for arsenic are made from brown rice: processed rice products like brown rice syrup, brown rice pasta, rice cakes and brown rice crisps. These processed products are commonly consumed by those following a “healthy” whole grain rich or gluten-free diet, but they clearly pose a significant risk of arsenic overexposure, especially if a person eats more than one serving per day. Obviously, brown rice is not a food that should be a dietary staple, or even eaten on a regular basis.

Aside from having a higher arsenic content, there are other reasons to avoid brown rice: it’s harder to digest and nutrient absorption is likely inferior to white rice because of phytates in the rice bran. Despite a higher nutrient content of brown rice compared to white rice, the anti-nutrients present in brown rice reduce the bioavailability of any vitamins and minerals present. Plus, brown rice also reduces dietary protein and fat digestibility compared to white rice. In short, brown rice is not a health food for a variety of reasons, and a higher arsenic content is simply another reason to avoid eating it.

No food is completely safe or without some level of contamination risk: vegetables make up 24% of our arsenic exposure and tap water can legally contain 10 ppb arsenic per litre (some systems even exceed the legal limit.) So while rice may contribute an unsafe level of arsenic, it’s certainly not the only source in our diet, and we need to be cautious about demonising an entire class of food based on a sound bite from a news story. Whilst rice may not be a necessary component of a healthy diet, it can be incorporated safely as a source of starch: just be sure to pay attention to the brand you’re buying, as well as your method of preparation.

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