Health Implications of Arsenic in Our Food System Webinar

Beth Anderson: Good afternoon, and welcome to the NIEHS Partnership for Environmental Public Health
Web Seminar, titled Examining and Communicating the Health Implications of Arsenic in our Food System.
I'm Beth Anderson. I'm a Program Analyst for the Superfund Research Program at NIEHS. I'm also a
member participant in the PEPH Program. So I'm going to be the Moderator for today's session.
Today we have two presenters – Dr. Margaret Karagas and Ms. Laurie Rardin. The first presentation we
will be given by Dr. Karagas. Dr. Karagas is the Director of the Children's Environmental Health and
Disease Prevention Research Center at Dartmouth and the Project Leader on the Dartmouth Superfund
Research Programs. She received her Ph.D. in Epidemiology from the University of Washington after
which she joined the Dartmouth Faculty, where she heads the section of Biostatistics and
Epidemiology. Her work encompasses interdisciplinary studies designed to eliminate the pathogenesis
of human disease beginning in early life and impacting health throughout lifespan.
So, Margaret, I'll turn that over to you, ready to go?
Margaret Karagas: Yes, just going to show the screen here. Okay, can everyone see the screen? So I
appreciate the opportunity to talk about the collaborative work we've been doing at Dartmouth on
life exposures stemming from our Superfund Research Program where we've been looking at drinking
water exposure to arsenic, and then extending with our new Children's Center to look at dietary
factors. And I recently presented some of these data at the Annual Children's Center meeting, so
those of you who attended that meeting, this talk will sound a bit familiar.
So there are documented early affects of arsenic in experimental systems relating arsenic exposure
to congenital anomalies, including [neuro two] defects, abrogati growth, and infant mortality. And
data from highly exposed populations to drinking water arsenic suggests affects on fetal and
neonatal mortality, spontaneous abortion, and stillbirth, as well as low birth weight and
prematurity, infection, and cognitive decline in children.
Arsenic can cross the placenta such that concentrations in maternal blood paralell those found in
cord blood, and this is illustrated in the study of Andean women exposed to high 200 micrograms per
liter arsenic in drinking water, where it can be assumed that the mothers' blood arsenic
concentrations were on average 11 micrograms per liter, which is similar to what's seen in the
infant cord blood, which was around nine micrograms per liter. And placenta tissue, itself, which
regulates nutrient flow into the fetus, also contains arsenic.
The drinking water standard for arsenic has declined over time as our knowledge of the health
effects of arsenic and the general population have grown. So in 2001 the U.S. lowered the standard
to 10 microgram per liter with some states having gone even lower based on the NRC recommendations,
which is New Jersey. However, it's important to recognize that private wells that serve less than 25
individuals or less than 15 households are not regulated.
This presents a problem for rural states, like ours and New Hampshire, where a significant
proportion of the population relies on private unregulated drinking water systems. So when we
designed our pregnancy cohort we decided to focus on pregnant women who use private water systems.
Our study is focusing on the New Hampshire population, and we're including a region that has – where
we have found in our previous epidemiologic work had wells that were above 50 micrograms and up to
800 microgram per liter. And the concentrations over 50 are shown as the large red dots, and the
orange dots show where the levels are above the current standard of 10 micrograms per liter. And,
indeed, what we're finding is about 15% of women in our study have a household tap water that
exceeds the current [MCO] of 10 micrograms per liter. So this is a cause for concern.
For most people who don't have high arsenic concentrations in their drinking water, diet is the main
exposure route. And currently there are no statutory limits for arsenic content in food sold in the
U.S. or the EU. In China the limit is 0.15 microgram per gram. And I participated in a European Food
Safety Authority Committee a few years ago, and based on an extensive review of food arsenic values
across Europe, review of the epidemiologic literature, and a detailed risk assessment we concluded
that dietary exposure to arsenic should be reduced.
Rice is a staple food worldwide, and it's also one of the major dietary focuses of arsenic. And this
is a synchrotron image of a rice grain, generated by my colleague, Tracy Punshan here at Dartmouth.
And showing in red is arsenic as it's entering the rice grain through the ovular vascular trace.
Available data suggests that the arsenic levels in rice are highest among U.S. rice and this is
shown by the black bar here. But you can also see that there's very wide geographic variability in
arsenic content of rice worldwide.
And this variability is in part due to paddy field biochemistry, rice zoology, including the
genetics of the rice [cultivar]. And one potential source of the arsenic is soil residues of
arsenical pesticide, from old cotton fields where rice is now grown.
One biomarker for arsenic exposure we use in our study is urine. Urine is a short-term biomarker
that reflects exposure within the past few days. This more elaborate pathway is shown on the left,
the metabolic pathway for arsenic, and I'm going to focus on this more simplistic model here. So
arsenic undergoes reduction from arsenic three or [arsenate to arsenite], and the [arsenite to
arsenate], which is arsenic five. And then it's monomethylated and then dimethylated.
So arsenic five and arsenic three are referred to as inorganic arsenic and monomethyl arsenic and
dimethyl arsenic are referred to as organic forms. Now this is distinct from arsenic that's found in
fish, which is an organic arsenic that's essentially unmetabolized, called arsenic betaine. And,
obviously, this is distinct from organic food, meaning food grown without pesticides. And the reason
I mention this is that there's been confusion by the media and others on the various forms of
arsenic.
To look at forces of arsenic exposure in pregnancy we used information from mothers and their
medical records to derive variables, such as age, smoking, and gestational age. And in addition to a
urine sample, we asked them to collect a water sample from just their kitchen tap and then to
complete a three-day water, seafood, and rice intake diary. The samples were analyzed by ICPMS. The
water samples were analyzed in Brian Jackson's lab at Dartmouth, and the urine samples at the
University of Arizona Superfund.
What we found was that roughly one-third of the women in our study reported eating rice, and those
who ate rice reported eating about a half a cup a day. And the concentrations of each of the arsenic
fractions were higher in rice eaters than non-rice eaters. You can see that for each of the
fractions, including inorganic arsenic, and these were all statistically significant.
We also fit general linear models to the data, so what we did was we took the amount of tap water
women reported that they consumed and multiplied it by the arsenic concentration that we measured in
their tap water. And then we modeled rice intake alone as a food item without assuming any specific
arsenic concentration because, as I showed you, arsenic concentrations vary so widely, there was no
one individual value we could assign to the rice.
Urinary arsenic was our primary outcome measure and which excludes [synobetaine], so a sum of all
the other species. And then we adjusted for maternal age and creatnine concentration which adjusts
for urinary dilution, which is fairly conventional. And I think also noteworthy is we have very low
detection for our assay, so for each of the fractions we have about 0.1 to 0.15 microgram per liter detection.
So what we found was that arsenic intake from drinking water was associated with increasing arsenic
concentrations, with the line here. And this is fully expected and we've seen this before in other
populations. But the new finding was that rice consumption was independently associated with urinary
arsenic concentrations after adjusting for arsenic intake from water.
So based on our model eating about a half a cup of rice per day equated to drinking one liter of 10
microgram per liter arsenic in water, and we published these findings a few months ago in PNAS, a
post author, who is now a Professor here, Diane Gilbert-Diamond was the first author with shared
authorship with Dr. Kathy Cunningham.
And Dr. Cunningham, along with Dr. Punshan and Jackson, are leading a project in our Children's
Center looking at infant and toddler exposure to arsenic, with concern both about infants getting
arsenic through the drinking water from the wells and, as well, arsenic through rice products. And
her project is also investigating various biomarkers of arsenic exposure in infants and toddlers.
In an initial market basket study levels get fairly high in some formulas and over the current MCL
of 10 microgram per liter, particularly in those formulas containing brown rice syrup. And this is
potentially worrisome for young children if they rely on this kind of formula as a primary source of
nutrition. And the results motivate us certainly to look further into this and to study the
biomarker concentrations in the infants, as we are now doing. And Laurie Rardin is going to speak
much more about the messaging.
But let me just mention a few limitations of our work so far. Our analysis of individuals' arsenic
exposure from rice, we did not actually test the rice, itself, nor did we know what brand it was or
the country of origin of the rice. And it's very likely that we didn't fully account for all sources
of rice, such as rice fillers and sweeteners, which we're doing a much better job with in our kid
studies. And our analysis of the infant and toddler formula we don't have the actual infant exposure
levels, such as biomarkers in urine. And, in any case, we need to better understand the health
impacts of food sources of arsenic exposure, which is the focus of our ongoing work.
So, in conclusion, we find that in our study population of pregnant women drinking water arsenic
from private wells related to urinary arsenic excretion, and that rice alone without accounting for
arsenic content of rice was associated with urinary arsenic concentrations in pregnant women.
So if we're thinking about reducing exposure we need to consider multiple exposure routes. We also
need to think carefully about our messaging, which is what Laurie is going to talk about. We
obviously know that people who have a private well, especially those in susceptible subgroups, like
pregnant women and kids, need to have their well tested for arsenic in our regions. And this is a
focus of our community engagement activities. And then we need to think very carefully about making
nutritional recommendations, and we don't want to repeat some of the same mistakes we've made with
mercury, where pregnant women stop eating fish due to fears of mercury contamination, yet fish has
nutritional benefits.
So I will stop here, acknowledging a vibrant group of collaborators and creative thinkers that I
have the honor to work with. In bold are some of the authors that are on the papers that I've
discussed here. I want to thank the NIEHS and the EPA and everyone in the audience.
Beth Anderson: Thank you very much, Margaret. So we'll take a few minutes to have some questions for
Margaret. So one of – the first question that I received or we received is should I be concerned if
I eat a half a cup of rice once a week?
Margaret Karagas: Okay, so I wonder about if we should wait until after Laurie's presentation, which
is going to talk more about messaging to people, to take these questions, what do you think?
Beth Anderson: Certainly, that one can – we can – I was kind of wondering about that, too, but maybe
– and the other questions and you can tell me if you think this is better addressed after your
presentation, Laurie, is what is known about arsenic in rice cereals designed for infants?
Margaret Karagas: Yes, so those are both really good questions. I'm happy to either address them now
or wait till after Laurie's presentation. I think I can just say briefly that what we're – the
messaging that we're getting from this work that we're doing now is just to highlight the wide
variability there is in arsenic content of various rices. So we're – the work is encompassing rice
products very generally, and we're going to be testing more products through our work, and so the
work that Dr. Cunningham and others are doing now.
So our point I think of the papers is to alert people that there is arsenic in rice and that this is
something that we need to regulate. As I mentioned, right now the U.S. and Europe really doesn't
have a statutory limit for arsenic in food, and so this is something that we feel needs to get
changed. But, again, we don't want to send the wrong message because rice is a nutritious food, we
just need to be able to monitor the amount of arsenic that's in our food. So it comes down to more
of a regulatory issue than it does an individual level issue.
Beth Anderson: Okay, thank you, Margaret. And, like you said, maybe we should -- based on the nature
of the questions that we have we should wait until after Laurie's presentation and then the two of
you can kind of answer the questions together.
So, with that, we'll go ahead. I'd like to introduce Laurie Rardin, who has worked in the
environmental communications field for over 20 years. She was an Environmental Science Major at
Connecticut College and received her MES from Yale School of Forestry and Environmental Studies,
with a concentration in Environmental Communications. And her experiences have given her a keen
understanding of the need to create two-way dialogue between researchers and end users to ensure
that research questions and the results are used to benefit public health in the environment.
So over the past several years as a Research Translation Coordinator with the Dartmouth Toxic Metals
Superfund Research Program, Ms. Rardin has faced many exciting challenges in communicating some late
breaking news regarding arsenic. And so I believe that's some of which is what she's going to be
sharing with us now. So, Laurie, I'll turn it over for your presentation.
Laurie Rardin: I'm happy to be here. Starting, to continue on with part two of the presentation, and
glad to be talking with a lot of you that I think I saw at the PEPH Biannual Meeting, so we can
continue some of the conversation that we started. So I'll be talking about perspectives on
complexities of communicating the emerging science on arsenic in food.
Okay, so I am the Research Translation Coordinator for our Dartmouth Toxic Metals Superfund Research
Program, and we have an interdisciplinary program, this is just an illustration of the way our
projects fit together and we're supported by our Trace Elements Analysis Corp, run by Brian Jackson,
and our Integrated Biology Corp run by Jason Moore. And we have the three biomedical projects,
looking at arsenic and its effect on human health. Margaret does the epidemiological birth cohort
work. And we have the two non-biomedical projects, one looking at mercury, and one looking at
arsenic in rice.
And those have been moving forward and working together very in a way to complement one another, and
the research translation comes in to make sure that the research results are getting out to our
stakeholders and to end users who can make use of that information.
And in terms of the work we've done on arsenic and rice, it's been clear that we have a risk
communication message that needs to get out and somewhat of a challenge. And just, as Beth alluded
to, with all the papers that we have had published recently and a lot of the national media it's
really brought everything kind of out in the open. And I'm going to talk a little more about that.
Quickly, I just wanted to back us up a bit. A very simple explanation of risk from one of our
government partners, the New Hampshire Department of Environmental Services. One of their drinking
water FAQ sheets. Risk is a result of an exposure to a hazard, and they want you to be sure or want
the public to understand there must be a source of risk and an exposure to the hazard. And they go
on to talk about the fact that it's possible even though there is a source of risk you might not
necessarily ever be exposed to that risk.
In the case of exposures in food there are additional factors to consider, though. That is that the
source of exposure has benefits, as well as risks. There may not be any knowledge of the contaminant
in the exposure source, the food, and the potential for the level of exposure varies widely,
depending on a variety of factors, such as age, weight, frequency of consumption, and the amount
consumed by the individual.
Some background information on risk communication. Many of you out there may be very familiar with
this, but when we think about communicating risks we have to think about perception of risk. The
public perceives risk differently. And [Paul Slovak], and Fischoff, some of the experts in this
field, Fischoff has identified that risks that are familiar, voluntary, natural, or under our
control are not as much of a concern to people as risks that are considered exotic,
unfamiliar, or involuntary.
And another part of risk perception is also the fact that nowadays there's so much information out
there on everything, as well as our science continues to develop. There's – we can look at things at
lower and lower levels in terms of analyzing the levels of contaminants and the effects that they're
having on human health. So there's a lot of information for the public to process.
And this book that I have, the cover on the right side of the slide, I just found something I think
I will be reading soon, A Practical Guide for Deciding What's Really Safe and What's Really
Dangerous in the World Around You.
But that's part of what we're trying to do is help people make those decisions. Risk communication
is defined in very broad terms by [Lundgren] and [McMeeken] into care communication, consensus
communication, and crisis communication. And I won't go through those. I've given a little squib as
to how they're defining those, but I think where we are is care communication
with the arsenic in food issue.
There is a danger and a management that's determined by our research. A good example is smoking, we
were able to definitively tell people that smoking was an extreme hazard to your health, and by
doing so we're working on protecting human health.
So in our program our science has been maturing, especially regarding science relating to arsenic in
food, and in our case rice. And we began a market basket pilot project through the Superfund
Research Program, and that, as well as the pilot project work being done by the Children's
Environmental Health Center has contributed to the three papers mentioned here. And the one, the
first paper is the one that Margaret was describing earlier in her talk, in more detail. And then
the third paper is the one I'll discuss a little more, which has received the most
and the largest amount of publicity.
So as our science is maturing and just when we thought the public was understanding that brown rice
was better for you and organic food was good for you because of being grown without pesticides, then
we move into a new area when Dr. Oz kind of cracks the issue open for us. We knew we had to get the
word out, but he sort of helped lay some of that groundwork.
And after this presentation I'm curious to see whether you think that Dr. Oz and the consumer
reports, media, publicity helped the situation or made it more difficult. So if you want to vote you
can let me know by e-mail afterwards. You don't have to tell me during the questions and answers.
But I'm just – it's something I'm wondering about, and it's certainly opened everything up.
So there was Dr. Oz September 13th, which there was a lot of controversy between Dr. Oz and the FDA.
Then Consumer Reports came out with a very thorough investigative report covering arsenic in juice,
as well as rice and water. The PNAS paper that Margaret mentioned came out on December 5th, and that
received a lot of media attention.
But on February 16th the paper led by Brian Jackson, Arsenic Organic Foods and Brown Rice Syrup, was
released through – it's published in EHP Online, right now, in the online format, and it'll be
published in their journal in May, but it received 23,000 hits to the EHP website within the first
week of its release. It generated about 50 media news stories, multiple news reports, including
major networks, a story on NPR. Brian Jackson received at least 300 e-mails from concerned
individuals, numerous e-mails were received by coauthors for the paper,
as well as others in our program.
Now I'm going to switch gears on you. We'll come back to this story and how we handled it and what
we learned from it, but as a way of thinking about framing our message, especially when we're
talking about emerging science where we don't have all the answers,
I'm going to give you something to think about.
So I drive up and down the highway from Concord, New Hampshire to Hanover on a regular basis, and I
pass these LED message boards along the highway. And they flash a variety of messages. One recent
one was about the weather. The first flash was extreme weather advisory. The next one was snow,
sleet, freezing rain. The third reduce speed to 45, stay off the roads. So that's a risk message in
a nutshell. It's very clear, they presented the problem, they gave information about the problem,
and they gave us an action.
So if I had been smart when I saw that message I would have gone home, done my workout, and laid
down on the couch, but if you think about a message like that for arsenic in food, what would you
say on one of those LED boards that was flashing along the highway? Would you say arsenic might be
in your cereal because information about the problem, because we know there's arsenic in rice and
your food is made, maybe made with rice products, but we aren't sure whether how much of that is
organic or inorganic, et cetera. There's still a lot of unknowns.
And what is the action that we tell them to take? Drop the bowl of cereal, don't eat it. We can't
say that because that wouldn't be responsible because of
the issue of nutrition of these food products.
So it's important that we think in terms of how to communicate with the public, what do they need to
know, and how do they think? And, again, back to the risk perception issue, when a scientist thinks
about communicating information – I love this illustration, and I first saw it at the PEPH meeting.
[Ed Kang] had it up in his communications session. Anyway, the background, scientists give the
background first, then they end up with their results and conclusions.
The public reads the bottom line first, the so what, and then supporting details are fine. The
emerging science that we're dealing with surrounding contaminants in food we have to consider those
risks and the benefits, and we have to realize that we're dealing with a lot of gray area.
So we have a responsibility to present our research. We need to get the information out, but we also
have to be prepared to answer difficult questions and try our best to think about what are the
effects, what action should I take, what do we know, and what don't we know.
Additionally, when we have this kind of emerging science, especially around a food related issue, we
have to think about how we're going to release our results. Typically, we might have our press
office in our college or university help us issue a press release. If we know that there's potential
for a media flash, as I'm calling it, we have to think about how is the press release written. It's
going to – if it's a press person, a press office, they're going to want to get publicity for the
college, they're going to write it with a certain type of hook to draw the media in. That might give
it an angle we don't necessarily want, so you need to think about that.
Again, it's a food issue. We have to convey the benefits, as well as the risks, and we have to, as
Margaret mentioned, we have to be careful about making recommendations that could change an
important dietary requirement for an individual.
So here is some lessons we've learned. Prepare ahead, what you know, think about what you know, what
you don't know, what you're trying to find out. People will respond if you tell them what you're
trying to discover, what are you researching, what are the questions you're trying to answer.
Keep your messages clear and simple.
Now time your release. This was a big lesson that we learned. If you're going to embargo your paper
you need to pick a date that works for your program, for your whole program because everyone might
end up needing to be in response mode. If you have more than one spokesperson make sure you're all
using the same message and think about notifying practitioners in the area who might be receiving
calls for information.
We had our regional PEHSU, our Pediatric Environmental Health Specialty Unit in Boston, receiving
calls about arsenic in toddler formula and other rice-based products. We also found out at the PEPH
meeting that the PEHSU out in the West Coast was receiving calls, too. So think about that.
Important, too, to think about what kind of numerical information is going out. Is it using
different types of measurements, like parts per billion or micrograms per liter? Is that going to
make sense to the media and/or to the people reading that information, say, in a news article? Will
they know how to interpret these numbers? Is there a way for them to gauge the risks from these
numbers and put it in perspective?
Is there a way you can give them some kind of illustration to help them understand what the numbers
mean, and is there a possibility that that numerical information could be skewed? We did have that
happen, some of the numbers that were used in the arsenic and organic brown rice syrup paper were
skewed by the media, and they were blown-up in a way they shouldn't have been.
So what did we do? Getting back to our story, we ended up putting up an FAQ response onto our
website, on our home page. We evaluated the e-mails that we were receiving and went – kind of came
up with the top six or so questions and put together simple responses to those questions.
So it's important to think about before you go out with your message what kind of background
information you'll want to have available, keep it clear and simple, and consider talking to local
communities to get a sense of the types of information that would be helpful to them. Perhaps put
together some focus groups.
It was clear from the e-mails that we received that people were very grateful for this information.
And it's important that researchers remain objective and trusted resources. That's essential,
especially today with the glut of information from all kinds of sources that may or may not be
reliable. Scientists and researchers need to keep that trust. So a good way to do that is to
maintain dialogue with your stakeholders, with your end users, with the public.
So the end of our story for now, we're continuing our work, as Margaret mentioned, but on February
17th the FDA put up on its website a statement on arsenic and organic and brown rice syrup stating
that beginning in October they began a further study of arsenic in rice and rice products to
determine level and types of arsenic found, and the study is due to be completed spring 2012.
So, in my opinion, one objective has been met, which is we've started a dialogue on setting
standards for arsenic in food. So now maybe we can consider moving on to the consensus communication
level, category in terms of continuing looking at how we are framing
these messages regarding arsenic in food.
So, with that, I want to thank folks in the Superfund Research Program, the Children's Environmental
Health and Disease Prevention Center, the Office of Public Affairs through the College. They really
did a great job helping us, as well as some folks from other SRP Programs and [Ed Kang] at NIEHS.
So I can – happy to answer questions now with Margaret.
Beth Anderson: Thank you very much, Laurie. That was – really appreciate your presentation. I want
to thank both you and Margaret. You gave us a good idea of the recent advances in arsenic in food
and also on how you approach communicating this information. Certainly, it's a hot topic that's been
in the news, and I think we also appreciate you sharing some important lessons that you've learned.
So I'm going to remind people to enter your questions into the question box, and we've got a few so
I'm going to go ahead with the first question and let you and Laurie,
our group figure out who wants to respond.
So did you send your paper to the MFR of the baby formula or notify them of
your study prior to publishing?
Laurie Rardin: Margaret, I believe – I don't believe so. Margaret,
I don't think that happened, correct?
Margaret Karagas: What does the MFR stand for again?
Laurie Rardin: Manufacturer.
Margaret Karagas: Oh, the manufacturer? That is a question that Brian Jackson – do you know, we need
him on the line.
Laurie Rardin: Well, we can – we'll check in with him for a definitive response, but to my
knowledge, no, but I can follow up and be sure that's the correct answer.
Beth Anderson: Okay. Thank you. So another question, was there mention of long grained rice as
having the most arsenic? Are these results true for short grained rice, as well?
Laurie Rardin: That may be another question that we would have to check with Brian on in terms of
specificity, but in terms of these products I don't think that we have a way of knowing whether they
used long or short grained rice. Say, for example, the organic brown rice syrup, I don't know that
we can – we have that information from the manufacturer as to the exact types of rice they're using.
And, again, I could confirm that with Brian, but does that sound right, Margaret, to you?
Margaret Karagas: Right, I mean in our study of pregnant women we did not ask them, at least
initially until we started looking at our data, what type of rice specifically they were eating and
what brand it was or what country it was from. So we didn't have a lot of detail about the types of
rice they were eating. We're collecting that now, that we see these results. So they're all issues
that need to get explored and.
Beth Anderson: Okay. Thank you. So, again, we get the question, can we get a copy of the slides? And
we generally do – we do make them available, if possible, so, Justin, do you have a comment on that?
Are you prepared for that?
Justin: We are not prepared at this moment, but if you would like to e-mail me at
[cranej2@niehs.nih.gov] or [Liam] or the PEPH e-mail address, which we'll show later, I will be
happy to get you those slides when they're available.
Beth Anderson: Okay. The next question is how do you convey to people that some of the arsenic in
the comparisons, a half a cup rice equals one liter of 10 parts per billion, is coming from the
water used to cook it, the water may be the controlling terms?
Margaret Karagas: Right, so in that – in those computations we assumed that there was no arsenic in
the drinking water, so it's a conservative estimate. So it's not – we're assuming that the water
arsenic is zero. I think that's the question.
Beth Anderson: Okay. Thank you. Kind of along similar lines is the 10 parts per billion MCL for
arsenic in drinking water is set as a level that is feasible, though it does not have any
relationship to the actual level of dietary arsenic that presents an unreasonable or reasonable risk
to public health, is there any evidence in your research that actually determines, and I just kind
of lost the question here – is there any evidence in your research that actually determines the
level of dietary arsenic that may present an unreasonable risk to public health?
Margaret Karagas: That's a really important question and one that we're addressing in our research
right now, so that was one of the third bullet points I put in the limitations of our research right
now, what we're presenting here is some preliminary evidence that arsenic is found in certain foods
in the formulas, and specifically I mentioned for infants and toddlers, in the toddler formula, that
had the brown rice syrup. And then in our pregnancy cohort it's really an exposure biomarker study.
We have yet to look at the health consequences downstream of those exposures, but that's something
that we're investigating moving forward. So neither or any of the research that we presented today
relate arsenic ingestion from rice to a health outcome. Is that clear?
Beth Anderson: Okay. Another question is rice milk is a great alternative for children with
allergies, do you have any suggestions of what could be an alternative?
Margaret Karagas: Is that a question for me?
Laurie Rardin: Well, yes, Margaret. I can take it if you want, but go ahead?
Margaret Karagas: Well, I mean again what I mentioned before is that really we're not making any
dietary recommendations in this research, we're just alerting really we're trying to inform
regulatory agencies and like what Laurie said, is the FDA did respond and say that they are going to
be following up on the brown rice syrup issue. So that's our goal.
Laurie, did you want to add anything?
Laurie Rardin: No, that's about what I was going to say, as well.
Beth Anderson: Okay. I have another question, have any food manufacturers or retail food companies,
especially health food stores, contacted you?
Laurie Rardin: Yes, and again we have – we certainly would have more – we could provide more details
once we check back with Brian because he has all that information and most people were contacting
him directly, but yes we have been in touch to a point, and yes.
Margaret Karagas: So I haven't had any direct contact with the manufacturers.
Beth Anderson: Another question, as a pediatrician how should I respond to parents who are deeply
concerned that they have irreversibly harmed their children by feeding them other brown rice syrup
products and who are insistent upon a biomarker testing that, in my opinion, does not inform
prognosis or treatment decisions?
Laurie Rardin: Well, I would – Margaret, you can back me up here – I'm not sure whether we could
answer you definitively except that the information that Margaret presented indicated that arsenic
does not remain in your system. It is excreted after a couple of days, so my understanding is,
unlike mercury, it doesn't bio accumulate.
And while there is definitely a different set of factors for a baby or a child as compared to an
adult, you know, that's the thing, the science is still emerging, there's still many unknowns. And
as a pediatrician or from me to you as a pediatrician I couldn't tell you what to do, but I would
just – I think it's important that people understand that it doesn't build up in the system and
it's, for an adult anyway it tends to be a long-term exposure issue.
Margaret Karagas: Well, I think this is a really good question and one that we really have to work
on to present to the pediatric community and the clinical community because these results are fairly
new. It's not actually measuring a child, it's not a recommendation that we've been making. Again, I
think really what our research is trying to alert regulatory bodies is the presence of this
contaminant in food and that we need to monitor our food to understand what is in our food. So
that's the main message that we're trying to relay here at this juncture.
Laurie Rardin: I think one additional point, though, to make would be that it's important – I mean
you want to allay your patients' fears, but at the same time you could also mention to them that
it's important to think about total arsenic exposure so if they were potentially on a private well
they would need to think – that would be an opportunity to say, well, have you tested your well?
Because you want to be exposed to the least amount of arsenic as possible, that's clear. So that's
important to think about, as well.
Margaret Karagas: That is for sure, and that I mentioned in my presentation, that that is the
message that we actually, we tried to get out when the first PNAS paper came out, but that's
something we know, if you have a private well you should have it tested, so that really is a clear
message, I completely agree with Laurie, and that's the message we tried to convey, although the
media wasn't as excited about that message as they were the other.
Beth Anderson: We've got a couple more question and just a few more minutes, so I'm going to try to
get in maybe one more question. I think how are you able to determine that arsenic in rice is from
former agricultural land use and not naturally occurring in the soil?
Laurie Rardin: I don't think that's anything – I'm not sure that we have determined that. We just
know that it is a factor, but is combined with the naturally occurring arsenic that's in the soil
and from water that's used to irrigate rice fields that may contain arsenic that could come from
natural sources or from pesticides.
But what we do know is that a lot of rice is grown in fields that were used to grow cotton,
particularly in the southern regions of the U.S., and that there was an arsenical based pesticide
used to control the Boll weevil on those cotton fields, and that there is residue remaining in the
soil from that use. And we know that rice takes up arsenic as you may all know now, but that's
something particular to the rice plant that it takes up the arsenic, thinking that it is silica, so
it's very specific to rice.
Beth Anderson: Okay. Well, thank you. This – your presentations generated a lot of interest, and we
have a few more questions, and we'll try to get – take care of those after the call and get
responses on these others two.
I do want to add one message that we got that says keep up the good work, this is exactly the type
of science-based public health research that is needed to get the policymakers to act in today's
anti-regulation political environment. Maybe I should just have stopped with keep up the good work,
this is exactly the type of science that we need. So I do want to thank you both for really fine and
interesting presentations.
And so before we close I want to make a few announcements to everyone. We want to know do you have
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I want to mention that the next PEPH webinar is going to be Mapping and Environmental Public Health,
Visualizing Health Disparities and the Affects of Pollution. It's scheduled for May 7th and you can
register already, so you register on go.usa.gov/iit, is that up on the slide now? Oh, well, you can
see it on the slide there, but I encourage you to go ahead and register. That's available now, and
that's going to be presented by our colleagues at [Columbia, Mayer, Smith Golden, Alexander
Van Geen, Steven Shelrod].
So then I want to encourage you, also, to after today's seminar take a moment to fill out our short
webinar evaluation form. Your feedback is really important to helping us ensure that we're providing
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And if you have any news that you want to share, please use the PEPH newsletter, the e-news
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So our time is up. I want to, once again, thank Dr. Margaret Karagas and Ms. Laurie Rardin. And that
concludes our webinar for today. Bye.