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New Study Reveals Long Term Decline In Blood Lead Levels In Children
Flint Area Lead
Poisoning Prevention Efforts Called A “Public Health Success”, Not A
Crisis As Portrayed
Will New Results
Change The Narrative About Flint?
The episode of increased lead levels in the Flint
Michigan water supply in 2014-2015 has been in the national spotlight
many times in the last few years. Many Americans were appalled at the
reported conduct of public officials in causing and handling the
problem. Now the publication of a new study of blood lead levels in
children in Pediatrics by Hernan Gomez and colleagues has
concluded that the lead exposures did not really constitute a public
health crisis as portrayed. A potentially new narrative about Flint
may be emerging.
Not Poisoned
In further elaborating a different perspective, Gomez
and University of Cincinnati epidemiologist Kim Dietrich, a
lead expert, published in the New York Times in late July an op-ed
article entitled “The Children of Flint Were Not Poisoned”. They state
“…the furor over this issue seems way out of proportion to the actual
dangers to the children from lead exposure.” So if not a public health
crisis, what did take place in Flint?
New Books
The new study comes at the same time as publication of
two books describing the Flint episode. One book called “What The Eyes
Don’t See” is by Mona Hanna-Attisha, the pediatrician who
succeeded most in bringing public attention to the problem. The second
book takes a broad, multi-factoral view of the underlying causes of
the episode by Detroit writer Anna Clark. It is entitled “The
Poisoned City: Flint’s Water and the American Urban Tragedy”. Both
books have received favorable reviews in the New York Times.
The books, the new study, an accompanying editorial,
and the op-ed article are provoking controversy around the use of the
word “poisoned” to characterize what happened to the children in
Flint. They raise questions in retrospect about what should have been
the appropriate response to the findings in Flint. Calling a situation
a crisis is diametrically different from seeing it as a success and
impacts any responses.
Initial Findings
The findings which triggered the declaration of a
public health emergency were those from Hanna-Attisha’s study showing
what percentage of children under five had blood lead levels above the
CDC reference level of 5 micrograms before and after the switch to
water from a different source.
[According to CDC, the
reference level of 5 micrograms per deciliter is based
on the U.S. population of children ages 1-5 years who are in the
highest 2.5% of children when tested for lead in their blood. The 5
micrograms level in not an established threshold at which children are
poisoned by lead. No safe blood lead level in children has been
established.]
According to Gomez, who is a medical toxicologist,
considering both the amount of exposure and the length of time
exposure occurs are important considerations in evaluating lead
toxicity.
In Hanna-Attisha’s studies, the percentages of children
with blood lead levels above the
reference level rose
from 2.1% to 4% in an initial study and from 2.4% to 4.9% in a later
study. In findings from the Michigan Department of Health and Human
Services, children under sixteen showed an increase from 2.37 % before
the water switch took place to 3.21% afterwards.
New Study
In
the new study published in June 2018, Gomez and colleagues evaluated
the percentage changes in blood lead levels above the reference level
in children under five. They did this over an 11 year period inclusive
of years before, during, and after the switch back to the original
water supply in 2015.
They found a significant long-term decline in the
percentages of children with levels above the reference level from
11.8% in 2006 to 3.2% in 2016, a 72.9% decrease. In studying actual
blood lead levels or mean geometric titers (GMT’s) over this 11 year
period, Gomez and colleagues found a linear 50.6% decrease from 2.33
in 2006 to 1.15 in 2016. The decreasing linear trend suggested that
random variation rather than increased lead exposures might best
account for some of the titer changes measured over the eleven year
period, including the increases observed during the period when the
Flint water source was switched.
According to Gomez and co-authors, “The random variability of the data
suggests that, whereas no child should have been unnecessarily exposed
to drinking water with elevated lead concentrations, changes in
geometric mean blood lead levels in young children in Flint Michigan
during the Flint River water exposure did not meet the level of an
environmental emergency.”
Health Scare?
If not an emergency, what was it? An overblown,
unfounded health scare? A real problem nevertheless? A warning sign
about urban area problems? A harbinger of future water system
challenges? A case-study in mismanagement? So far there seems to be no
agreed upon or clear answer to these questions.
Toxicohistrionics
An editorial in Pediatrics accompanying the Gomez
report suggests it might be an example of “toxicohistrionics” defined
as “public and professional overreactions to substances in our food
chain or environment where real risk has been exchanged for
theoretical risk.” The editorialist, William Banner, current
President of the American Association of Poison Control Centers, goes
on to state that “reporting in the media and publication never gave us
a real sense for the degree of ‘crisis’”.
Letters To The Editor
Many of the letters to the editor published in the NY
Times following the Gomez and Dietrich op-ed article are critical of
the researchers for suggesting that the word “poisoned” was inaccurate
and stigmatizes children in Flint.
One letter from Anna Clark, the author of one of the
new books about the Flint episode, says “To parse wording about
'poisoned' is to miss the point entirely. A violence was done to
Flint, and especially to its young persons. Naming it as such is truly
the least we can do.” And she adds, “The community that fought so long
for its concerns to be taken seriously is not served by continued
intimations that it wasn’t harmed enough to count as
‘poisoned’.”
Difficult Message
Gomez and Dietrich were well aware that differences
between the casual use of the word “poisoned’ and the nuances of the
medical and scientific application of the word, (that is to say
“permanent brain damage”) would not be well received by a fair portion
of the Times’ lay readership. No child deserves to be exposed to lead,
said Gomez, but those making an extra effort to understand can see
that a true poisoning (i.e., permanent brain damage) did not take
place. Gomez believes the op-ed was successful in sending an
important message, and told the Monitor he has received expressions of
gratitude from health professionals across the country.
Public Health Success
In seeking to describe the Flint situation in the
context of their long-term observations, Gomez and Dietrich
call the 11 year decline in blood levels in Flint children a “public
health success” even when taking into account the change in the
water supply.
They conclude, “It is therefore unfair and inaccurate to point a
finger at Flint and repeatedly use the word “poisoned”. All it does is
terrify the parents and community members here who truly believe there
may be a ‘generation lost’ in this city, when there is no scientific
evidence to support this conclusion.”
Why The Overreaction?
If indeed the reactions in Flint were excessive given
what appears to be the low level of real risk, what caused such an
exaggerated response? Part of the answer may be found in the social
and economic conditions and distrust existing in Flint prior to
2014-15 which primed everyone to believe the worst. These conditions
are extensively documented in the book by Anna Clark.
In an interview with The Epidemiology Monitor, Clark
was quick to recognize the difficulty of identifying a single label or
pinpointing a cause for what she called the “violence” that the Flint
population was exposed to. “Flint has suffered so many amorphous harms
and indignities in the past,” she said, “it was a relief during the
lead episode to be able to point to it as a kind of validation by the
outside world for the multiple concerns of the community.”
Other factors have also been elucidated in case studies
of electromagnetic fields, radon and passive smoking by Geoffrey
Kabat in his book entitled “Hyping Health Risks”. He warns that
“Ultimately, by failing to put certain potential hazards in
perspective, one confuses the public and diverts attention from issues
that may be far more important.”
Right Label
As noted by Clark, the Flint story is now moving from
the realm of “news” to the realm of “history.” What remains unclear is
what will become
the definitive narrative of what happened in Flint.
This is important as it will guide the lessons learned from the
experience. Also, as pointed out by Gomez and Dietrich in their op-ed
piece, words are toxic too, and the potential toxicity of words used
about the children deserve serious consideration just as the potential
toxic effects of lead in their water. ■
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