Arsenic in Rice: Health Hazard Quantified
A critical look at health warnings in Consumer Reports magazine
- "Arsenic is bad for you." True
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"Rice contains measurable amounts of arsenic." True
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"For the sake of your health, it's important to limit your intake of rice." False
The harm of arsenic in rice is so small (see below) that you're better
off directing your attention and effort to the much larger hazards that
exist in your daily life.
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In this essay, I analyze articles published in Consumer
Reports magazine on the presence of the harmful element arsenic in rice. I explain why I think the warnings in these articles raise undue alarm and fear among readers.
Let me start by saying that I have nothing against Consumer Reports. In
fact, it's my favorite magazine. I've been a continuous subscriber since
1978, and I read every issue. The Consumer Reports articles are well-researched and well-written, and
I'm not disputing the background facts presented in them. I'm only questioning the conclusions drawn from the facts, namely, that you should modify your diet to reduce your intake of arsenic.
Arsenic in Rice
Arsenic in your food is the headline in the November 2012 issue
of Consumer Reports, with bold subheadings Studies show that arsenic can cause cancer in humans and Our study shows people who eat rice have higher arsenic levels. (This same article is available online at the ConsumerReports.org website.)
Consumer Reports published an update article in the January 2015 issue of the magazine and online, How Much Arsenic Is in Your Rice; and separately issued a detailed report, Analysis of Arsenic in Rice and Other Grains, November 2014.
The articles are well-researched and well-written, and based on extensive
research and testing done by Consumer Reports at considerable effort and
cost. I have no dispute with the background information presented in the
articles.
However, I disagree with the general tone, that arsenic is a significant hazard
to your health. I feel that these articles raise unnecessary fear and anxiety among readers,
possibly driving them to take actions that actually hurt their health.
Limiting Your Rice Consumption
For example, the Limit your exposure part of the article recommends
that you eat no more than two servings of rice per week. If you replace the
rice with another plain cooked grain such as oats, wheat, quinoa, millet, or amaranth as they
recommend in their How to cut your arsenic risk section, that's
good. However, if you live in the United States, and if you
don't live in a Buddhist monastery (and maybe even if you do), you'll
probably replace the rice with something like pasta, bread, or potatoes.
Check the "Nutrition Facts" labels of the rice and the replacement
food, including the sauces and toppings that you use with these foods. How do they compare?
Rice is virtually fat-free and
sodium-free. There's a good chance that the hazards of the replacement
food more than offset the benefit of arsenic reduction.
Suppose, for example, that cutting your rice intake from seven to two
servings per week decreases your arsenic intake, thereby reducing your lifetime
risk of developing cancer by 1 in 50,000. You replace the five
servings of rice with an equivalent amount of bread, increasing your sodium
intake, thus increasing your lifetime risk of suffering a heart attack or stroke
by, say, 1 in 5,000. In that case, switching from rice to bread would actually harm your health.
I'm not saying that you should or shouldn't switch from rice to bread.
The purpose of this hypothetical example is to illustrate that cutting
back on rice is not necessarily good for you. To make an informed decision about taking a course of action, you need
to know not only the benefits, but also the costs
of that action, quantitatively.
Rinsing Rice and Cooking It in Extra Water
The How to cut your arsenic risk section of the Consumer Reports article recommends that you rinse your rice before you
cook it, and cook it in extra water and discard the excess liquid when
it's done, which removes some of the arsenic.
As mentioned in the article, some vitamins and nutrients are lost in the process.
This is what the Food and Drug Administration has to say about this
practice:
Published studies report that thoroughly rinsing rice
and cooking it in volumes of water five to six times that of the rice
can reduce up to roughly half of the arsenic content. At the same time,
such preparation may well lower the nutritional value of the rice (i.e.,
the folic acid content of fortified rice and some B vitamins).
The FDA is not aware of any studies that have determined the net benefit
of reducing the arsenic at the expense of the nutrients also removed.
Thus, the agency does not know whether there would be any overall health
benefit from preparing rice with more water.
-- Food and Drug Administration, U.S. Department of Health & Human Services
Questions & Answers: Arsenic in Rice and Rice Products
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The FDA is saying that there's a benefit to using extra water to reduce the arsenic, but they can't say
whether that benefit exceeds
the harm of losing the vitamins. As an extreme case, an undernourished
pregnant mother might actually harm her unborn baby
by rinsing her rice before cooking. Spina bifida, a congenital disease caused by lack of folate, affects about 3 in every 10,000 births in the
United States, according to the Centers for Disease Control and Prevention (CDC). Compare that with the 1 in 50,000 risk of harm from dietary arsenic (maybe; see my analysis below).
However, for most people in the United States, the vitamins lost from
rinsing the rice can be easily made up by eating a varied diet, by
eating other enriched foods, or by taking a supplement. Whether you rinse
your rice and cook it in extra water might depend on whether you think
it's worth the trouble. To reach that kind of decision, you
need to know quantitatively about the risk involved. I make an attempt to do this in the following sections.
How Harmful Is Arsenic in Rice?
The Arsenic in food page of the Consumer Reports article lists several dozen brands of rice and
rice products and their inorganic arsenic content. Samples containing
more than
5 micrograms per serving highlighted in red. At the top of the page,
they explain their testing and recommendation methodology:
There is no federal limit for arsenic in most foods,
but there is a federal limit of 10 parts per billion for arsenic in
drinking water. The most protective standard in the country is New
Jersey's at 5 ppb. At that limit, drinking a liter of water would expose
you to 5 micrograms of inorganic arsenic. That provides a yardstick by
which you can compare the ranges of inorganic arsenic per serving
detected in the samples we tested ...
-- Consumer Reports, November 2012
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The Consumer Reports article highlights rice products containing 5
micrograms or more of inorganic arsenic per serving, the same as what you'd get from
drinking a liter (about a quart) of water containing New Jersey's
restrictive upper limit on arsenic in drinking water. If they had
followed the federal standard instead, all of the products would have met their safety requirement, and none would be highlighted in red.
So how did the U.S. Environmental Protection Agency (EPA) arrive at a 10
parts per billion (ppb) standard for drinking water? And why did New
Jersey set a more restrictive standard?
In 2001, the EPA announced the lowering of the Maximum Contaminant Level (MCL) of arsenic
in water from 50 to 10 ppb. They considered setting the standard at 3, 5, 10,
and 20 ppb and settled on 10 ppb as the best choice, considering benefits versus costs:
How much will this rule cost?
EPA estimates the total treatment cost to be approximately $177 million per year.
What are the benefits of this rule?
The rule will protect approximately 13 million Americans ... Reducing
arsenic from 50 to 10 µg/L will prevent [approximately] 19-31 cases of
bladder cancer and [approximately] 19-25 cases of lung cancer per
year ... The quantified annual benefits for today's rule range from
$140 to $198 million.
[Note: µg/L means micrograms per liter, which is the same as parts per billion.]
-- Environmental Protection Agency
Technical Fact Sheet: Final Rule for Arsenic in Drinking Water
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The EPA also established a Maximum Contaminant Level Goal (MCLG) of
zero,
meaning that there is no absolutely safe level of arsenic.
Since any
amount of arsenic in water is harmful, why didn't the EPA set
the MCL level at 5 or 3, instead of 10? The answer lies in their
cost-benefit analysis. Setting the MCL standard
at 5, for example, would have greatly increased costs, as more water
providers would be affected, while the added
benefit of arsenic reduction would be not as much, since the reduction would be from 10 to 5 ppb rather than from 50 to 10 ppb.
The reduction in the MCL from 50 to 10 ppb helped 13 million Americans
reduce their arsenic intake and cancer risk, at a cost of about $3.5
million per case of bladder or lung cancer prevented. Suppose, for the
case of argument, that the same $3.5 million applied to reducing
perchlorate (another harmful pollutant in water) could prevent, say,
four cases of cancer. Then the public would be served better by applying
the money to perchlorate reduction instead of arsenic reduction. In
fact, more cancer cases could be prevented by raising the allowed arsenic level while reducing the allowed perchlorate level.
I'm not saying that the 10 ppb standard established by the EPA is too
high or too low. I'm just pointing out that establishing a good
standard, with the goal of providing the greatest possible
benefit to the public, is far from straightforward. It is not simply a
matter of setting the level "as low as possible" or "at the smallest
level that can be detected," based on the simple fact that arsenic is
bad for you.
A Quantitative Estimate of Rice Consumption Risk
So back to rice. The statistics provided the EPA provide a means to quantify, at least approximately, the benefit of reducing rice consumption.
According to the EPA study, 13 million Americans now benefit from the
reduction of arsenic MCL in drinking water from 50 ppb to 10 ppb. That
means 13 million Americans were drinking water containing somewhere
between 10 and 50 micrograms per liter of water, and now they are
drinking water containing no more than 10 micrograms per liter.
Let's say they drink 2 liters per day, including bottled and canned
drinks prepared from municipal water supplies. In that case, their
arsenic
consumption from water was reduced from somewhere between 20 and 100
micrograms per day to 20 micrograms per day. Let's make a guess that the
average daily consumption before 2001, for those who gained a
benefit, was 60 micrograms. This is now 20 micrograms, a decrease of 40
micrograms per day. This
reduction prevents roughly 50 cases of bladder and lung cancer among
the 13 million of those helped, or about 0.0004 percent, per year.
Now let's look at rice consumption. Suppose that you are now eating
seven servings of rice per week, each serving containing arsenic at the
Consumer Reports warning level, 5 micrograms. You consider cutting this
to two servings of rice per week, a reduction of five servings per week, or
25 micrograms of arsenic per week, or about 4 micrograms of arsenic per
day on average. We'll assume that the replacement food is
arsenic-free and otherwise just as healthy as rice.
This reduction is 4/40 of the average reduction experienced by the 13
million
Americans affected by the EPA's lowered MCL. The decrease in
your bladder and lung cancer risk is 4/40 of 0.0004 percent, or about
0.00004
percent. That's the risk reduction for a single year. The lifetime benefit is
maybe 50 times this amount, or 0.002 percent, or 1 in 50,000. Let's
assume, as an approximation, that bladder and lung cancers are the only
cancers caused by arsenic.
To put this in perspective, let's look at the average overall lifetime
risk of developing cancer for Americans, as measured by the National Cancer Institute and reported by the American Cancer Society:
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Lifetime risk of developing cancer |
Lifetime risk of dying from cancer |
Males
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43.92%
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22.94%
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Females
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38.00%
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19.34%
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So for the U.S. population as a whole, the average lifetime risk of
developing cancer is about 40 percent. If that was your risk when eating
seven servings of rice per week, cutting back to two servings per
week would reduce
your risk to 39.998
percent. Is that a worthwhile benefit? In my opinion, it's better to
direct your attention to the much larger hazards described in Box A below.
Brown or White Rice?
Is brown or white rice healthier? Consumer Reports notes that brown rice
typically has more arsenic than white rice of a similar type. Does this
mean you should switch from brown to white rice to reduce your arsenic
exposure? In my opinion, absolutely not! First of all, the amount of
arsenic is very small in any case, as explained earlier. Second, brown
rice is much more nutritious in other respects: more fiber, more
vitamins, less effective carbs, smaller glucose spike, and so on.
Finally, the actual difference arsenic exposure might be minimal or
nonexistent. The reason that brown rice contains more arsenic is
presumably because the fiberous outer grain coating retains more of the
arsenic that was present in the water used for irrigating the rice
field. Remember, fiber passes though the body undigested. Might the
extra arsenic present in the fiber pass all the way through the body and
get excreted in the stool, and not get absorbed into the bloodstream?
If that's the case, then brown rice exposes you to no more arsenic than
white rice.
It seems to me that someone with lab experience could answer this
question with a simple experiment. Feed some volunteers large servings
of brown rice with relatively high arsenic, say 10 ppb. Measure the
amount amount of arsenic present in the excreted stool and compare it to
the amount consumed in the rice. Repeat the experiment with a white
rice diet and a non-rice diet as controls.
Clean Water? Then Go Ahead and Enjoy Rice
Check the annual water quality report from your city. Is there no
measurable arsenic in it, as in my city? Good! You can enjoy two
servings of rice every single day at the Consumer Reports action
level, and still stay within New Jersey's restrictive limit on
arsenic in water (by comparing to water intake of 2 liters per day).
Bottom Line on Arsenic in Rice
This is the advice from the FDA's Q&A website on arsenic in rice:
What is FDA recommending to consumers about eating rice and rice products?
Based on the currently available data and scientific literature, FDA's
advice for consumers, including pregnant women, is to eat a
well-balanced diet for good nutrition and to minimize potential adverse
consequences from consuming an excess of any one food. Additionally,
parents should follow the advice of the American Academy of Pediatrics
and feed their infants and toddlers a variety of grains as part of a
well-balanced diet.
Is rice safe to eat? Is it safe for children to eat?
Rice is an important staple for many people, and the arsenic levels that
FDA found in the samples it evaluated were too low to cause any
immediate or short-term adverse health effects. All consumers, including
pregnant women, infants and children, are encouraged to eat a
well-balanced diet for good nutrition and to minimize potential adverse
consequences from consuming an excess of any one food.
-- Food and Drug Administration, U.S. Department of Health & Human Services
Questions & Answers: Arsenic in Rice and Rice Products
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The FDA's recommendation to eat a well-balanced diet does not specifically cite arsenic in rice
as a reason for doing so, and does not say to avoid rice. I interpret their recommendation as "Go ahead
and eat rice if you like it, even if you're pregnant, even for young
children. Just don't go overboard and eat rice (or any other single
food) every meal, every day."
Based on my own analysis, I have the following recommendations:
- Before you even consider the possible danger of arsenic in rice, concentrate your attention and effort on more significant
health and safety issues that are under your control, such as those described in Box A below.
- If you decide to eat less rice, make sure that the replacement food is equally healthy.
Otherwise, the harm of the alternative food might exceed the benefit of
the reduced arsenic.
- If you decide to rinse your rice and/or cook it in extra
water that you pour off, make sure that you eat a
well-balanced diet, eat other fortified foods, or take a vitamin
supplement. Otherwise, the harm of nutrient loss might exceed the
benefit of the reduced arsenic.
- Don't switch from brown to white rice. The benefits of brown rice exceed the possible harm (if any) of higher arsenic exposure.
For more information about arsenic in water and food:
Environmental Protection Agency, Basic Information about Arsenic in Drinking Water
Food and Drug Administration, Arsenic
Arsenic in Food, Lundberg Family Farms (organic rice grower)
Significant Health and Safety Hazards
The next time you hear about the latest health hazard du jour in the news, take a look at the known significant
hazards in Box A below. If you can answer "yes" to all the listed
questions, you're doing great, and you can consider whether the dangers
of 4-MEI, arsenic, chromium-6, BPA, and so
on are worthy of your concern. If you answer "no" to any listed
questions, focus your attention and effort on those items, and don't worry
about what you hear in the news.
BOX A
Significant Health and Safety Hazards Under Your Control
-
Have you stopped (or did you never start) smoking? CDC
- Do you maintain a healthy weight? CDC
- Do you drink alcohol moderately (or not at all)? "Moderately"
means no more than two drinks per day for a man or one drink per day for
a woman. CDC
- Do you drive a car only while free of influence from
alcohol, drugs, fatigue, and distracting electronic devices? Do you
always obey traffic laws and wear your seat belt? NHTSA
- Do you refrain from using illegal drugs, and from using prescription drugs for non-medical purposes? NIH
- If your household has firearms, are they securely
locked out of sight, and accessible only to responsible, emotionally stable adults? HSPH
- Do you always wash your hands with soap and water before
preparing or eating food, and after using the toilet or taking care of a
sick person? CDC
- Do you exercise at least 30 minutes every day? CDC
- Do you eat at least five to eight servings of fruits and vegetables every day? HSPH
- Do you consume no more than one or two sugary drinks per week? HSPH
- Do you consume no more than 2,300 mg of sodium per day if you
are young and healthy, or no more than 1,500 mg per day otherwise? CDC
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More health warnings: 4-MEI in Pancake Syrup: Health Hazard Quantified
Disclaimers: I'm not a
doctor or other health care professional, and I have no special
knowledge or experience in medicine or toxicology. I have no connection
with the food industry, health care industry, or Consumer Reports
magazine (other than being a subscriber). I believe the information here
is correct, but errors are possible. Use
the information at your own risk. You're encouraged to do your own
research to reach your own conclusions about the issues raised. This
website is not intended to provide medical advice. Before changing your
diet or starting a new exercise program, check with your doctor to make
sure that the change is OK for you.
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