PORTSIDE Archives

June 2012, Week 2

PORTSIDE@LISTS.PORTSIDE.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Portside Moderator <[log in to unmask]>
Reply To:
Date:
Sun, 10 Jun 2012 20:55:38 -0400
Content-Type:
text/plain
Parts/Attachments:
text/plain (210 lines)
The Arsenic Diet
By Deborah Blum
Wired Science
June 8, 2012
http://www.wired.com/wiredscience/2012/06/the-arsenic-diet/

In late May, the organic baby formula maker Nature's One
announced a goal of "zero arsenic" in its product. Good,
you say. Great. Makes perfect sense. Or it would except
for this question -  why is a poison like arsenic, of
all things, an issue in baby formula?

Read a little further in the Nature's One press release,
and you'll find a direct link to the problem. The link
goes to a February study, published in the Journal of
Applied Chemistry, titled "Arsenic Concentration and
Speciation in Infant Formula and First Foods."

That study, I want to emphasize, found nothing panic
worthy, nothing but very trace levels of arsenic in
formula and baby food. But, still,  as I wrote last
week, arsenic can have health effects at a surprisingly
low dose. It's no wonder that  Nature's One so
determinedly wants none of it.

But there are other things to wonder about here. Such as
-  why does arsenic so inconveniently turn up in the
food supply? And are public health officials doing
anything to protect us in this regard? These are
connected questions but I'll give you one heads up on
the latter. In the United States,  the Environmental
Protection Agency sets a safety limit of ten parts per
billion for arsenic in drinking water. But - to the
frustration of advocates and scientists -  the Food and
Drug Administration offers  no safety standard for
arsenic in food .

And that matters because study I cited is just one of
many telling us that there is some risk here. The word
speciation in that title refers to the type of arsenic.
The basic division  is between organic (a carbon-
containing compound) and inorganic arsenic. It's a big
division actually. Our bodies metabolize organic arsenic
compounds efficiently and they are not particularly
dangerous.  Inorganic arsenic, by contrast, is notably
dangerous. And it's that more poisonous variation that
turned up in the baby formulas and cereals.

And here, as they say, is where the story gets
interesting.

The researchers of that study, based at Dartmouth
College, identified rice as the primary source of
inorganic arsenic. They found it (again, in very tiny
amounts) in rice syrup used to sweeten baby formula,
rice cereal,  rice flour used in making crackers and
cookies. This does not mean that rice is by by nature  a
poisonous plant. It isn't.

But both soil and groundwater can contain arsenic -  as
a naturally occurring element and as a residue from the
use of arsenic-based pesticides. And , as the Dartmouth
scientists noted,  "Although As (arsenic) is not readily
taken up by crops or transported to the edible parts, a
notable exception is rice.The magnitude of this uptake
varies widely between cultivars but the ability to take
up elevated concentrations of As (in comparison with
other cereal crops) appears to be a trait found in the
entire rice germplasm."

In other words, rice turns out to be outstandingly good
at absorbing arsenic from the environment and storing
it.  One reason is that the plant is designed to easily
absorb the mineral silicon which helps give rice grains
their elegantly smooth structure. The crystalline
structure of arsenic is just close enough that rice
plants readily uptake arsenic as well. In fact, a toxic
metal study, also from Dartmouth, describes rice as "a
natural arsenic accumulator."

The efficiency of this system also means that the
arsenic tends to be absorbed directly in its more toxic
inorganic from rather than being converted to an organic
form of arsenic. And rice, experts say, seems to be a
primary source of arsenic in the human diet..  Or as a
newly published book  by Andrew Meharg,  at the
University of Aberdeen in Scotland, Rice and Arsenic,
puts it, "Rice is the major exposure route globally to
the non-threshold carcinogen inorganic arsenic."

Scientists and public health officials - although not
the general public - have known this for years. I won't
inundate you with the studies that have piled up since,
say, the year 2000 but here's a few: from 2002 "Arsenic
Uptake and Accumulation in Rice  (irrigated with
contaminated water); from 2003 "Uptake Kinetics of
Arsenic Species in Rice", from 2005, "Bioavailability of
Inorganic Arsenic in Cooked Rice" and  from 2008,
"Arsenic in Rice, II: Arsenic speciation in U.S. Grain
and Implications for U.S. Health."  Recently, though,
the public started to catch on. There was widespread
coverage of a February study from Dartmouth this year,
"Arsenic, Organic Foods, and Brown Rice Syrup," which
cited  unexpected amounts of inorganic arsenicin
everything from infant formula to snack bars, especially
compounds containing rice or sweetened with brown
organic rice syrup as a healthier alternative to high
fructose corn syrup.

I wrote about that last study earlier in a post called
On Rice and Arsenic so I won't dwell on it in detail
here except to talk about some of the fallout. Although
I'm focusing on rice here, it's important to recognize
that it's not only source of concern in the American
diet. I can easily think of two others that have come up
in the last year.

One involves the use of commercial poultry feed that
contains organic arsenic as an additive. This additive
was approved by the FDA in the 1950s, both to kills
parasites and to improve the look of packaged chicken
(the arsenic caused blood vessels to explode and the
meat to look pinker). The argument had been this was
only harmless organic arsenic but last year FDA tests
found that it was metabolizing into the toxic inorganic
form. The pharmaceutical giant, Pfizer, suspended sales
of the feed, Roxarsone, pending future tests. The FDA
did not ban continued use of feed already on the market,
however, or move to prohibit future use. Impatient with
the federal delay, Maryland is now moving to ban
Roxarsone itself.

The other, as you may remember, involves  apple juice.
That issue was first raised by the Tampa Bay Times in
2010 and amplified by Dr. Mehmet Oz in 2011. In November
of last year, Consumer Reports published its own tests
on both arsenic and lead in fruit juice. In December,
the magazine publicized yet another study on arsenic and
rice. Both the magazine and  Consumer's Union, the
related advocacy group, have been asking  the FDA to
take some official action on arsenic in the food supply,
to set safety standards for American consumers.

"We need to come up with a universal standard," agreed
Joshua Hamilton, a senior toxicologist at the Marine
Biological Laboratory in Woods Hole, Massachusetts, and
author of numerous studies on low-dose effects of
arsenic. In an interview with NPR's The Salt, Andrew
Meharg, author of Arsenic and Rice, made the same point:
"The safety thresholds for chronic (inorganic) arsenic
in water are well established. Food needs to be put on
the same footing as water standards."

And this, I think, is exactly right. The lack of such a
standard leaves everyone uncertain as to what is safe
and what is not. It's unfair to the makers of baby
formula and juice packs and other products.  American
rice producers, for instance, have been left sounding
either defensive or uncertain as what to do. As
California's Lundberg Farm notes in some frustration on
its website, "as yet there are no federal or state
standards in regard to testing or as to what are safe
levels." And it's unfair to the rest of us too, parents
and  consumers trying to figure out what's safe in the
food supply and what isn't.

Which brings me back, as promised to the FDA. Following
that Dartmouth report on poison levels in brown rice
syrup, the agency announced that it was doing its own
study of the issue. The federal report was scheduled be
completed last month. Obviously, it wasn't so I've been
asking the FDA's public affairs office about it (in
fact, making a pest of myself for the last three weeks)
and I'm told that the report should be finished by the
end of this month. Do I expect the federal agency to
suddenly have all the answers to a complicated
environmental poison? I don't. But do I expect agency
officials to live up to their responsibilities to public
health and safety and set some minimal guidelines?

I absolutely do. I am counting on a late June report?
I'm absolutely not. But here's hoping that the FDA
proves me wrong.

(Note: This is the second of a series of posts I plan to
write on arsenic and public health. The first, Is
Arsenic the Worst Chemical in the World, was published
last week).

[moderator: and that post may be found here -
http://www.wired.com/wiredscience/2012/06/is-arsenic-the-worst-chemical-in-the-world/]

___________________________________________

Portside aims to provide material of interest to people
on the left that will help them to interpret the world
and to change it.

Submit via email: [log in to unmask]

Submit via the Web: http://portside.org/submittous3

Frequently asked questions: http://portside.org/faq

Sub/Unsub: http://portside.org/subscribe-and-unsubscribe

Search Portside archives: http://portside.org/archive

Contribute to Portside: https://portside.org/donate

ATOM RSS1 RSS2