Apples, Arsenic, and Risk - Part 7: Who the heck is Sharyn Duffy of Geneseo, N.Y.?

Okay, so if cancer at these low levels is not the concern the EPA says it is, would there be anything else that would cause Consumer Reports concern regarding the finding of inorganic arsenic in apple juice?  Here is what they report:

• Mounting scientific evidence suggests that chronic exposure to arsenic...even at levels below water standards can result in serious health problems.
• But the many diseases likely to be increased by exposure even at relatively low levels are so common already that its effects are overlooked simply because no one has looked carefully for the connection,” says Joshua Hamilton, Ph.D., a toxicologist specializing in arsenic research and the chief academic and scientific officer at the Marine Biological Laboratory in Woods Hole, Mass.
• It’s a carcinogen known to cause bladder, lung, and skin cancer in people and to increase risks of cardiovascular disease, immunodeficiencies, and type 2 diabetes.
• A 2004 study of children in Bangladesh (PDF) suggested diminished intelligence based on test scores in children exposed to arsenic in drinking water at levels above 5 ppb, says study author Joseph Graziano, Ph.D., a professor of environmental health sciences and pharmacology at Columbia University.
• And a study published in 2011 (PDF) in the International Journal of Environmental Research and Public Health examined the long-term effects of low-level exposure on more than 300 rural Texans whose groundwater was estimated to have arsenic at median levels below the federal drinking-water standard. It found that exposure was related to poor scores in language, memory, and other brain functions.
• Chronic arsenic exposure can initially cause gastrointestinal problems and skin discoloration or lesions. Exposure over time, which the World Health Organization says could be five to 20 years, could increase the risk of various cancers and high blood pressure, diabetes, and reproductive problems.
• Signs of chronic low-level arsenic exposure can be mistaken for other ailments such as chronic fatigue syndrome.
• “Given what we know about the wide range of arsenic exposure sources we have in this country, I suspect there is an awful lot of chronic, low-level arsenic poisoning going on that’s never properly diagnosed.”
• ...but also can cause lasting harm to children’s developing brains and endocrine and immune systems, leading to other diseases, too.
• “Recent studies have shown that early-childhood exposure to arsenic carries the most serious long-term risk,”
• Evidence of arsenic's ability to cause cancer and other life-threatening illnesses has surged because some of the diseases linked to it have latency periods of several decades.

So, what we come away with when reading the Consumer Report's article on Apples and Arsenic is this:

• Mounting scientific evidence...serious health problems
• Many diseases likely to be increased by exposure even at relatively low levels...overlooked
• Increase risks of cardiovascular disease, immunodeficiencies, and type 2 diabetes
• Diminished intelligence based on test scores in children exposed to arsenic in drinking water at levels above 5 ppb.
• Exposure was related to poor scores in language, memory, and other brain functions.
• Increase the risk of various cancers and high blood pressure, diabetes, and reproductive problems.
• Low-level arsenic exposure can be mistaken for other ailments such as chronic fatigue syndrome.
• Low-level arsenic poisoning...that’s never properly diagnosed.
• Lasting harm to children’s developing brains and endocrine and immune systems, leading to other diseases.
• Early-childhood exposure to arsenic carries the most serious long-term risk.
• Ability to cause cancer and other life-threatening illnesses has surged...latency periods of several decades.

Wow!  All that from drinking apple juice?

Not so fast, I'm thinking.  Let's look at it objectively, and ask two questions:

1. Is drinking apple juice unsafe because of arsenic?
2. Is drinking water with the 10 ug/L (ppb) of arsenic unsafe?

Now go back and read the bullets above, what answers to those two questions is being conveyed by Consumer Reports?

Is their report an accurate description of the dangers posed by drinking apple juice that they found had a mean (average) inorganic arsenic concentration of 3.14 ug/L (95%UCL = 3.53) and a median of 2.51 ug/L. (I took all 84 values and ran them using Excel's statistical formulas.  These values exclude three grape juice samples included in their data.)

Some of Consumer Reports' claims of serious health problems they support with a citation link, others are quotes for medical/science professionals, but one in particular is a testimony:

Signs of chronic low-level arsenic exposure can be mistaken for other ailments such as chronic fatigue syndrome. Usually the connection to arsenic exposure is not made immediately, as Sharyn Duffy of Geneseo, N.Y., discovered.

Okay, a real person affected by arsenic...

She visited a doctor in 2007 about pain and skin changes on the sole of her left foot. She was referred to a podiatrist and eventually received a diagnosis of hyperkeratosis, in which lesions develop or thick skin forms on the palms or soles of the feet. It can be among the earliest symptoms of chronic arsenic poisoning. But she says it was roughly two years before she was finally referred to a neurologist, who suggested testing for arsenic. She had double the typical levels.

Okay...she had hyperkeratosis...a skin lesion that's associated with arsenic exposure...she had double the typical levels...  Double?  Typical?

Okay....they named a real person, surely Consumer Reports checked out her story...where did they find her?  What do we know about Sharyn Duffy of Geneseo, N.Y.?  Aha! Google search...nothing.

What support do we have to show that a.) Sharyn Duffy was diagnosed with hyperkeratosis, and b.) she had double the typical levels?  Should we accept the diagnosis and quantification of arsenic presented in the Consumer Reports article as valid?  I tried - as much as I am willing to spend my free time on trying - to find any reference to her case.  Nothing.

I could discount it as "unsubstantiated" but where's the fun in that?

Here is what we know (if you can believe the EPA and ATSDR) about arsenic and skin lesions, such as hyperkeratosis:

[I]n a study with detailed exposure assessment, all confirmed cases of skin lesions ingested water containing >100 μg/L arsenic (approximately 0.0037 mg As/kg/day).

Another large study reported increased incidence of skin lesions associated with estimated doses of 0.0012 mg As/kg/day (0.023 mg As/L drinking water).

Several epidemiological studies of moderately sized populations (20–200 people) exposed to arsenic through drinking water have detected no dermal or other effects at average chronic doses of 0.0004–0.01 mg As/kg/day, and one very large study detected no effects in any person at an average total daily intake (from water plus food) of 0.0008 mg As/kg/day.

Notice how the intake of arsenic is reported in "mg" per liter?  Consumer Reports claims that Sharyn Duffy had "double the typical levels."  The plot thickens (no pun intended...you know...hyperkeratosis...oh, never mind...).

Here is a bit of interesting trivia we also read in the Consumer Reports article:

Because most ingested arsenic is excreted in urine, the best measure of recent exposure is a urine test.

Why's that important?  Because we can measure and get a pretty good estimate of how much total arsenic is being consumed on average - or typical.  And if we know that, we can then double it to find out how much arsenic Sharyn Duffy was exposed to.

In the Consumer Reports article they tell us:

[w]e commissioned an analysis of data from the National Health and Nutrition Examination Survey (NHANES), conducted annually by the National Center for Health Statistics. Information is collected on the health and nutrition of a nationally representative sample of the U.S. population, based on interviews and physical exams that may include a blood or urine test. 

It would have been nice of them to report these values, but nevertheless, we can get a good idea of what they are by looking at NHANES research that has been published.  Here is what I found:

Source Table has been revised since posting)

I am going to assume that Sharyn Duffy of Geneseo, N.Y. is > 20 years of age.  If "most ingested arsenic is excreted in urine" we can assume that the amount of arsenic that Sharyn Duffy was exposed to, if it was "double the typical levels" was approximately 20 ug.  What goes in goes out...

Remember those studies on skin lesions the EPA looked at?  Well here is what they concluded from those studies:

This value [0.0008 mg As/kg/day] has been used to calculate a chronic oral MRL for inorganic arsenic of 0.0003 mg/kg/day.  

EPA considers 0.0003 mg/kg/day "safe" but reports that 0.0008 mg/kg/day "detected no effects in any person at an average total daily intake (from water plus food)."

Let's assume that Sharyn Duffy of Geneseo, N.Y. is a petite woman who weighs 110 pounds or 50 kg.  At 20 ug total intake, she would be consuming 0.4 ug/kg/day or 0.0004 mg/kg/day to get "double the typical levels."

Okay, so she is being exposed to more than the EPA's "safe" dose, but it is way under the 0.0008 mg/kg/day where "no effects in any person at an average total daily intake (from water plus food)" were seen in "one very large study."

So maybe poor Sharyn Duffy of Geneseo, N.Y. is very susceptible to arsenic and the little bit she consumed (if we can trust that it was only enough to "double the typical levels") gave her the disease associated with much higher doses of arsenic.  How does Sharyn Duffy's experience with arsenic affect my answer to the questions I posed earlier:

1. Is drinking apple juice unsafe because of arsenic?
2. Is drinking water with the 10 ug/L (ppb) of arsenic unsafe?

It doesn't.  At worse, Consumer Reports got it wrong, and she was exposed to much more arsenic then "double the typical levels."  At best, Sharyn Duffy of Geneseo, N.Y. is an anomaly...an outlier...and we can ignore her encounter with arsenic because that's not what we would see in the public at large.

Onward....

Next Post: Apples, Arsenic, and Risk - Part 8: Arsenic and type 2 diabetes

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