6/9/2015 Meeting Summary
Advisory Panel to the
Environmental Health Tracking and Biomonitoring Program
1:00 – 4:00 pm at the American Lung Association in Minnesota
490 Concordia Avenue, St. Paul, MN
Attendees: Bruce Alexander, Jill Heins Nesvold, Melanie Ferris, Geary Olsen, Gregory Pratt,
Andrea Todd-Harlin, Cathy Villas-Horns, Lisa Yost
Regrets: Fred Anderson, Alan Bender, Thomas Hawkinson, Pat McGovern and Steven Pedersen
Staff: Paul Allwood; Jeanne Ayers, Betsy Edhlund, Carin Huset, Jean Johnson, Jim Kelly, Tess
Konen, MaryJeanne Levitt, Matthew Montesano, Paul Moyer, Christina Rosebush, Jeannette
Sample, Blair Sevcik, Chuck Stroebel, Paul Swedenborg, Janis Taramelli, Addis Teshome, Linden
Weiswerda and Ginny Yingling.
Guests: David Bael, Mary Dymond and Frank Kohlasch, Minnesota Pollution Control Agency.
Welcome and Introductions
Lisa Yost chaired the meeting for Pat McGovern, who was unable to attend. She welcomed
everyone and announced that the company she worked for had recently merged and the new
company name was Ramboll Environ. Lisa invited everyone to introduce themselves.
2015 Legislative Report
Paul Allwood, Assistant Commissioner for the Minnesota Department of Health, presented a
summary of the 2015 session and noted that there would be a special session scheduled soon.
He reviewed the finance bill that was vetoed by the Governor and observed that the language
for the bill submitted for the special session was identical, with the exception that continued
biomonitoring must include Hmong and immigrant farmers. There was also no indication of a
“$0” balance for EHTB in 2018, as had been previously implied. He explained that the Hmong
farmer language had been added due to concerns that Representatives Clark and Wagenius had
expressed that farmers renting plots in the area were not included, so that was an opportunity
to achieve higher levels of comprehensiveness in the monitoring efforts.
Hearing no questions from the panel, Paul asked Jim Kelly, Environmental Surveillance &
Assessment Director at Environmental Health of MDH, if he had any comments. Jim agreed with
Paul’s assessment of the session, adding that the new bill would fund continuing biomonitoring
efforts and also the air pollution and health work.
Jean Johnson noted that MN Biomonitoring was including the Hmong community in the
mercury, lead and cadmium study (MN FEET). We also have plans to conduct community
engagement with the Hmong farming community in the East Metro. Jean introduced the 2015
Legislative Report fulfilling a suggested element of the panel’s Sustaining MN Biomonitoring
Subcommittee communications plan.
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East Metro PFC3 Biomonitoring Project Results Analysis
Christina Rosebush updated the panel on the East Metro PFC3 Project. The background
materials can be found on pages 5-14 of the June 9, 2015 Advisory Panel Meeting book.
Christina noted that individual results had been sent out to participants in early April, along
with an informational brochure about PFCs. The brochure answered the questions:
•
•
•
What do my PFC test results mean?
What can I do to avoid PFC exposure? and
Do PFCs cause health problems?
The brochure stressed that water systems were still tested regularly, and PFCs in water were
below safety limits set by the Minnesota Department of Health. It explained how to interpret
the geometric mean and 95th percentile and summarized what is known about PFCs and health.
It included information that the C8 study in West Virginia/Ohio had found probable links
between PFOA and some health conditions but not others and that the IARC classified PFOA as
possibly carcinogenic based on limited findings in humans and animals. It concluded that
research continues on PFCs and health effects such as birth outcomes, hormone balance,
cholesterol levels and immune response.
Eighteen participants returned postcards requesting a study physician phone call and were
often Original Cohort (OC) members whose results went up. Study physician Dr. Winnett
explained to participants the possible reasons for increases, such as laboratory uncertainty or
new exposures and took the opportunity to emphasize usual preventive care.
In response to a question about the number of OC participants in the tables, Christina agreed
that tables and charts showing PFC levels over time should only include the 149 individuals who
participated in all three projects. She offered to send an updated table to Panel members via email.
The overall results were being presented for panel feedback on the community report. Christina
reviewed the key questions the study was hoping to answer:
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•
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Have PFC levels continued to decline in long-term East Metro residents?
In new Oakdale residents, are PFC levels comparable to U.S. general population?
Is there an association between length of residence in Oakdale since Oct 2006 and
PFC levels?
Christina reminded the panel that no subgroup analysis was possible in the Renters group, as
there were only 19 participants. The New Resident homeowners and renters were combined
into one group of New Residents (NR) with a size slightly lower than her previous presentation
(156) due to a few new residents not completing all study requirements.
The OC and NR were truly two distinct groups, even though each had 156 participants. They
came from entirely different source populations. Because eligibility criteria were different,
compared to the NR, the OC was older [OC=59.1 yrs. vs NR=45.9 yrs.], had lived in the East
Metro longer [OC=24.8 yrs. vs NR=3.7 yrs.], and was less diverse [OC=98 percent vs NR=84
percent White, non-Hispanic; OC=2 percent vs NR=16 percent Other].
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Income was slightly higher in the OC [OC=56 percent vs NR=44 percent≥$75,000/year], though
a larger proportion of NR were College graduates [OC=41 percent vs NR=57 percent).
In the OC, levels of the most commonly detected PFCs significantly decreased between 2010
and 2014. They were still higher than general U.S. population levels from the NHANES 2011 and
2012. Of note, levels of these PFCs were continuing to decline in the U.S. population as well.
A small group of participants had increases in levels of PFOS (15), PFOA (2) and PFHxS (17). For
the most part, participants who had increases between 2010 and 2014 were not the same as
those who had increases between 2008 and 2010.
Looking at geometric means, levels of PFOS and PFHxS were slightly higher in NR compared to
NHANES, but these differences were not significant. All confidence intervals overlapped,
indicating no differences between PFC3 NR and the NHANES subsample. Comparing the 95th
percentiles, no significant differences were seen.
Using geometric means and average interval between blood draws, the rates of elimination
were 6.3 years for PFOS, 3.2 years for PFOA and 8.3 years for PFHxS. The rates of elimination
using individual PFC results and intervals between blood draws: 7.2 years for PFOS, 3.4 years for
PFOA and 8.3 years for PFHxS.
Published half-lives were for groups with higher levels of exposure (3M occupational and C8
with PFOA levels over 50 ug/L). More blood draws were taken over time for these studies. The
PFC3 rates of elimination were not true half-lives because all sources of exposure were not
known or controlled for. However, they were very close to published half-lives.
Washington County residents may have been included in the NHANES 2011-12 biomonitoring
subsample, but they were unlikely to have comprised a large amount, perhaps 3-6 percent of
the subsample.
The final NR model was adjusted for age and sex, since levels of PFCs increased with age and
were higher in men compared to women. No associations were seen between blood donation
history and PFC levels.
In final adjusted models, there was no difference in PFC levels between homeowners and
renters. The complete analyses for NR will include diet and health history.
Christina described the community outreach plan. The Community Report will be mailed to
participants. Then MN Biomonitoring will work with partners in Oakdale, Lake Elmo and
Cottage Grove to make results available on city websites, attend city council meetings and
assess opportunities to join other local meetings. Another step would be to make the results
available to renters through the HRA, and finally, include the latest PFC work from Environmental Health. Christina asked for feedback for the community report of the overall results.
Questions presented to the panel were:
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Are there panel recommendations for additional analyses before presenting these
results to the public?
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What key messages are most important for informing the community about these
findings?
Is presenting the percent change in geometric mean over time or mean change in
individual PFC level over time best for communicating with the public?
Is the inclusion of Washington County residents in the NHANES subsample
concerning? Should MN Biomonitoring pursue additional information on the
Washington County subsample from NHANES?
Discussion
Bruce Alexander wanted more information about the people who had increases and what
might have contributed to those increases. If these increases had occurred all in people with
lower PFC levels possibly due to lab uncertainties, then that may concern the reliability of the
other results. Gregory Pratt commented that if he were one of the persons in the 95th
percentile or above, he would want more info about what he could do to lower his levels.
Lisa Yost suggested looking at the message of ongoing decline that we did expect and also
questioned whether there was any way to estimate the potential impact of the Washington
County/NHANES overlap. How many people from Washington County were expected to be in
the sample, and if they all were at the high level, what is the largest impact that those people
would be able to have. They were sampled in 2011, so that would have been five years after
the water switched over, so you would know something about what people would look like by
the PFC2 biomonitoring. Christina agreed that it may be possible to assess the impact on the
NHANES results by assuming (worst case) that 6 percent of Washington County had been in
NHANES and had the highest levels.
Lisa asked about the NHANES 2011-12 sample size. Geary Olsen responded that generally
NHANES was 3 or 4,000 sampling per sampling cycle for two years for any of these compounds;
it was a rolling subsample across the 30,000 people. It was a very small subsample and we were
not sure if Washington County residents had been tested for PFCs. Lisa commented that
NHANES may be able to answer, “Did the Washington County 2011 people get tested for
PFCs?”
Regarding the question for the Panel about selecting the best calculation for percent change,
Geary commented that showing geometric means over time for the sample of 149 and percent
change were both important. The average age of participants was 59 years. Harvey Clewell had
recently given an MDH presentation showing that there were clearance issues with these
chemicals that made doing a half-life calculation –or expected change calculation—hard to
interpret.
Geary added that it was important to keep in mind with these half-life estimations that there is
no right number because they are all bounded by confidence intervals. Geary suggested using
geometric mean half-lives, from his 2007 publication for calculation of predicted percent
change in the PFC3 cohort.
Geary asked about PFBA and the observation that concentrations were similar between New
Residents and the Original Cohort. Geary asked if the granular activated carbon (GAC) filters
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were working well, then are exposures from multiple sources, not necessarily the water. Jim
Kelly replied that that was certainly one possibility.
Paul Allwood asked about the averages that were discussed—geometric means vs. arithmetic
means and asked what the spread was like in the numbers of people that had been sampled for
the geometric means—was it clustered very closely? Also, for arithmetic means, was there wide
variation? Geary Olsen answered by giving the following highest values: PFOS was 448
nanograms/ml in 2008 compared to 180 today; PFOA was 177 in 2008 and today it was down to
47. Those were not necessarily the same people. For PFHxS, the highest value was 316 in 2008;
today it was 140. The highest ones were coming down. There was an identical distribution
between the people who had been exposed drinking the water and the residents who had not
been exposed.
Paul Allwood asked whether there had been any change in the untreated ground water over
time. Was there any attenuation of the plume before it went into the municipal treatment
system? Ginny Yingling, Site Assessment & Consult with Environmental Health at MDH,
answered that the Pollution Control Agency had done additional remediation of all three of the
major disposal areas and we were seeing some improvement of the water quality as a result of
that work and the potential ongoing migration. By and large the plumes were stable and we
had seen some slight decreases in some areas and slight increases in some areas.
Jeanne Ayers offered the following questions that she anticipated may come up at public
meetings: “What could I do to decrease my level? Would a decrease in my level make a
difference? Would an exposure make a difference in health impact?” She wondered what we
knew about whether or not the health impact of the exposure might not actually be responsive
to a decrease. Lisa offered the following potential response to those questions, “You were
already below the threshold—it was reassuring to see that levels continued to decrease, but
remember, you were already at levels that were considered to be safe from what we know
about the health effects of these chemicals”.
Biomonitoring Updates
Biomonitoring Updates were provided on the current status of the MN FEET project and
additional analyses of the East Metro Cancer Report in written form on pages 15-20 of the June
9, 2015 Advisory Panel book. Panel members were invited to ask questions of staff and
comment on all updates.
Jean noted that we were getting very close to launching the MN FEET (Minnesota Family
Environmental Exposure Tracking) project within the next two weeks. The project will work
with Hmong, Somali, Latina and White communities and will be recruiting through West Side
Clinic and HealthPartners. We will be recruiting pregnant women and measuring maternal urine
and cord blood. Recruitment for that study would be 12-15 months, so results would not be
available until 2017.
Jean noted that at the last meeting we had Kenneth Adams from the MCSS program presenting
the analysis of cancer rates in the East Metro. One of the findings had been an elevation in
breast cancer, so the recommendations from this panel were to go back and look at other data
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that might help us answer questions about why that might have occurred. Kenneth has
included in your book an analysis of staging data and mortality.
Mary Manning commented that we did not see early detection or screening as a reason, based
on the analysis that Kenneth completed. She added that if we looked at the literature, you
would see that higher affluence and the lower number of pregnancies among the women in this
area as possible explanations. Jean Johnson added the use of hormone replacement therapies
as another risk factor. Mary stated that for many people, there would be the question of
whether or not the PFCs were related. The literature did not show that to be the case, but we
could not rule that out, either. Lisa Yost thought that articulating the other known risk factors
would be helpful, since there may be natural concern upon seeing the cancer information.
Geary Olsen wondered whether MDH was prepared to speak to the public on this. Mary
answered that they were prepared and these were the type of findings that could possibly be
found all over the state. In response to a question about a press release, Mary was not certain
that there would be a press release on this. Jean Johnson added that Environmental
Epidemiology planned to have this report available when PFC results were presented to the
community, to answer questions that might come up about what the cancer rates were in the
community. Lisa Yost commented that since it was out there, maybe having a short summary
that interpreted these findings and also set them in context with other known risk factors
would be helpful. Mary thanked everyone for the feedback and said that Kenneth Adams of
MCSS was the MDH point of contact for people who wanted to discuss the report further.
State Air and Health Initiative
Jeannette Sample presented highlights from a new technical report on the impacts of air
pollution on the health of Twin Cities’ area residents. Background materials can be found on
pages 21-23 of the June 9, 2015 Advisory Panel book.
Jeannette began by introducing the Initiative coordinator, Mary Dymond, along with coauthor
David Bael, both with the MPCA, and Linden Weiswerda and Chuck Stroebel, both with MDH.
Jeannette gave a brief background of the joint MPCA and MDH initiative that arose out of
concern about air quality and health in the Twin Cities area. There were three joint deliverables:
a technical report that she would cover; a community toolkit that Chuck would present and a
health impact assessment (HIA) that Linden conducted. Jeannette added that Linden would not
report on the HIA today, but he was the contact person and was available for questions about
the HIA.
The new title Life & Breath: How air affects health in the Twin Cities was an update from the
title in the background materials book, Jeannette announced. It used the EPA’s BenMAP
(Benefits Mapping and Analysis Program) tool to estimate health effects of air pollution; the
number of health impacts resulting from changes in air quality.
Fine particle-and ozone-related health impacts had been estimated for each of the 165 ZIP
codes that lay entirely or partly within the seven-county Twin Cities metro area, Jeannette
explained. The seven-county Twin Cities metro area included the following conties: Anoka,
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Carver, Dakota, Hennepin, Ramsey, Scott and Washington. ZIP code level impacts had been
summed to provide metro area estimates.
In BenMAP, impacts were calculated using the equation [∆𝑌𝑌 = 𝑌𝑌 0(1 − 𝑒𝑒 −𝛽𝛽 ∆
)∗
p], with input data from the Twin Cities metro area by ZIP code. The following
definitions for the equation were explained by Jeannette: ∆𝑌𝑌 was the predicted number of
health outcomes attributable to the level of air pollution in the ZIP code, a measure of health
impact. 𝑌𝑌 0 was the baseline number of health events in the ZIP code, i.e., the 2006-2010
number of hospitalizations, ED visits or deaths. 𝛽𝛽 was the concentration response function
(effect estimate) as determined by epidemiological studies. ∆
was the change in air
pollutant concentration in the ZIP code (either PM2.5 or ozone), i.e., 2008 average
concentration minus naturally occurring background or a 10 percent reduction from 2008
average concentration.
was the size of the population in the ZIP code of the relevant
age group (e.g., 65 and older for estimating cardiovascular hospitalizations).
In the 2008 Downscaler annual average, the pattern for PM2.5 was higher concentration in the
central cities, Jeannette continued. For 03 there was an opposite effect, where it was higher in
the south and the east of the metro area, due to how ozone formed and was oxidized. There
was not a huge spread in concentration; Jeannette noted, Minnesota has had fairly good air
quality compared to the New York City, the city this report was modeled after; our levels were
lower.
For health data, Jeannette indicated they had used hospital discharge data: asthma emergency
department visits, asthma hospitalizations, respiratory hospitalizations and cardiovascular
hospitalizations. For the mortality data, they looked at all-cause mortality and cardiovascular
deaths. Results showed that in 2008, 6-12% of all metro area deaths (about 2,000 deaths) were
attributable to PM2.5 and ozone pollution, and about 2-5% of hospital admissions and
emergency room visits (hundreds of hospitalizations and ER visits) for heart and lung conditions
were attributable to PM2.5 and ozone pollution. If levels of PM2.5 and ozone were reduced by
10%, which was the goal of Clean Air Minnesota, it would prevent hundreds of deaths,
hospitalizations and emergency department visits due to heart and lung conditions every year.
Jeannette explained that looking at ZIP code levels; they found that the air pollution levels
across the metro area were not very different. What was driving differences in rates were
mostly the underlying health rates, so areas that had health disparities were also having air
pollution attributable health rate disparities.
With mortality rates, looking at PM2.5 attributable mortality, Jeannette said the report shows
that some of the higher mortality rates were outside the central twin cities, because of the
mortality pattern in the twin cities area. The report shows that impacts of air pollution fell
disproportionately on children and the elderly.
The ZIP code-level percentiles of poverty and populations of color, had also been looked at.
According to Jeannette, there was little variation in average air pollution levels, but for ZIP
codes with larger populations of people of color and residents living in poverty, there were
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higher rates of hospitalization for heart and lung conditions, asthma ED visits and death related
to air pollution.
Key messages to present with this report had been drafted, and the key messages were:
breathing polluted air could cause a variety of health problems; and everyone could be affected
by breathing polluted air, but some were impacted more than others due to underlying rates of
diseases. Jeannette added that to reduce the health impacts of air pollution, we needed to
improve air quality, but we also needed to address the underlying causes of health disparities in
order to address disparities in air pollution effects.
Chuck Stroebel introduced the second deliverable in the initiative, the Community Toolkit, or
the Be Air Aware website. He began by noting that the website addressed the need for more
communication with the public, providing access to health and air quality data, as well as what
they could do about it. This had been a joint initiative between MDH and MPCA. Mary Dymond
was the lead coordinator, with consultation and input provided by several MDH programs.
Chuck added that they began with a series of key informant interviews with target audiences to
identify content gaps on the web. They had found an interest in a better understanding of the
relationship between air and health, accessing tools and data, and what could be done.
Chuck noted that the focus was on the data, who was affected and actions that could be taken.
The mock-up site had a banner for news items, highlights, reports, tools, new initiatives and
activities. There was an area to access data on current air quality conditions from the MPCA air
monitoring network, the Air Quality Index, which was near real time data. Chuck added that
indoor air quality had been included, since people spend 85-90% of their time inside, and often
levels of air pollution were higher indoors, such as tobacco smoke and radon. The goal was to
put together the silos of indoor air and outdoor air data, with a focus on what the reader could
do to improve health and improve air quality for those target groups.
For local officials, Chuck continued, success stories were being developed about local actions
that could be replicated by other communities. One example was the Health Impact
Assessment (HIA) that could be used to address community concerns to better inform decision
making about land use.
In terms of communication and outreach, Chuck stated that they were conducting pre-release
stakeholder outreach with CleanAir Minnesota, local health officials and state agency staff.
Chuck informed the panel that the press release of the website and the report for the public
would be July 15th with an ongoing communications & outreach plan to follow.
Chuck presented the following questions to the panel for discussion:
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•
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What key findings from the Public Health Impacts of Air Pollution technical report are
most important for public communications?
How might the results/products of this initiative be used by agencies, organizations, and
our partners?
What suggestions do you have to inform future work on this initiative, including
additional technical analyses and data updates, and/or communications and outreach
activities?
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Discussion:
Cathy Villas-Horns asked how the authors knew that the hospital admissions were from the air
pollution that day. Jeannette responded that these were estimates; they had looked at an
annual average air pollution level and a five-year annual average for health events. A
concentration response function (beta) from the published literature was used. So they could
not say that a certain health event had been caused by pollution, but overall, 6-12% of deaths
based on the literature would be attributable to our level of air pollution in the metro area in
2008.
Lisa Yost agreed with Cathy Villas-Horn, adding that the report needed to be careful to say that
it was an estimate, not actual, and that the basis for the estimate was well described. Jeannette
replied that there had been discussion about the use of percentages or numbers, and there
were confidence intervals around these numbers. She also addressed the question whether
these numbers were directly attributable to air pollution, and, as you could see from the elderly
people or the people with preexisting conditions, it could have been an event that caused a
cascade of events leading to death.
Geary Olsen commented that the way this was presented, it looked like 10% of people die from
breathing bad air. It needed to be clear, saying that bad air contributed to a cascade effect and
ultimate death. He asked that Jeannette rephrase what the 6-12% actually meant from her
standpoint. Jeannette answered that it was not a direct cause. It could be someone with COPD
who would have had COPD on their death certificate. They may not have died that day, but it
was precipitated by an event (premature death. Geary agreed and added that he understood it
was a very difficult message to communicate to the public.
Lisa Yost noted that it was a very challenging task to communicate that air pollution was a
contributor, especially in populations at risk, leading to death. Mary Dymond responded that
this was where the questions usually came in response to the report. She commented that the
authors had thought of using the word “premature mortality”, which in a sense meant that
people, because of exposure to air pollution, died a little sooner than they would have
otherwise, partially related to the underlying conditions as well. Lisa thought it would help to
lay out the model that establishes a predicted relationship and use that model to get to
premature death, or increased likelihood of an emergency room visit.
Greg Pratt noted that the response function was based upon a broad spectrum of studies done
across the country. We conducted studies here in Minnesota and it might be useful to bring
that information to the table for comparison in this discussion.
Paul Allwood added that, regarding disparities, there were members of our community that had
high sensitivity and high susceptibility to the effects of air pollution. The number may seem
high, but if you looked across the entire population, from an ecological view rather than specific
populations, it may not be that unreasonable.
Jean Johnson elaborated on the study that Greg Pratt referred to, presented to the panel in
2012, where EHTB calculated the concentration response function linking the health data with
the MPCA pollution data. The difference was that we used an average of the monitors, so the
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method was different. The attributable fraction for hospitalizations was about the same at
approximately 2%. Geary asked what that 2% meant from a pathological process that led to
death. What part was actually attributed to air pollution versus smoking versus any other
event? The definition of attributable fraction, Jean Johnson responded, was what portion would
have been prevented if this exposure were removed to background, to the lowest achievable
level (or how many deaths would have been prevented if we removed all the human-caused
pollution).
Jean noted that we wrestled with how to explain ‘attributable fraction’ to the public. Geary
Olsen asked if that meant that those people would not have died. Greg Pratt used the example
of someone who had died in a car crash, whose death certificate would have said blunt force
trauma. If they died of a heart attack, a stroke, COPD or asthma, it would list one of those as
the cause of death. Air pollution might have contributed in the long term to that condition; it
also might have contributed in the short term to an event that caused death at that time. But
you were not going to see ‘air pollution’ on the death certificate. Geary agreed; his concern was
about the use of “would not have occurred”, because likely many would have occurred without
the air pollution, regardless. He asked, “Was there a calculation that said that the deaths would
not have happened because of not having the air pollution present”? If someone had
emphysema, this contributed to a premature death, but did that mean that a death would not
have occurred, based on how these things were calculated. Jean responded that it did come
back to premature deaths. The literature would have characterized it as “premature”; it would
not have occurred on that day, it might have occurred later, just not at that time, at that place.
Lisa Yost commented that the report may need a better description of the sections, ‘where did
we get that data’, ‘how were we using data on attributable fraction’ and ‘what kinds of studies
were used to come up with that’. We have to tell people how it worked. Jeannette added that
one of the things they struggled with was looking at a one- or five-year average. With a fiveyear annual average, it was hard to say whether that was premature because it was such a big
time frame, so we thought it would be easier to describe if we just said ‘deaths’ rather than
‘premature deaths’ to the public. She added that the messaging had been very challenging. The
report itself had been challenging, but the group had been spending many months figuring out
a way to convey the results.
Lisa Yost asked about the messaging regarding the use of 2008 data and today’s comparison
with air pollution. Jeannette responded that they had addressed that in the report; the level
had come down, and David Bael added that the level actually came down closer to 10% and
that we had already achieved the goal we set. But at the time we did this analysis, the 2008
data was the most recent data that covered the 7-county metro area. Jeannette added that the
next step would be to use the most recent data to see if we achieved the benefits we had
predicted.
Melanie Ferris commented that the other difficult messaging was that air pollution levels did
not really vary that much across the metro, but there were notable inequities in health
outcomes. So she was wondering if there was a way to be more deliberate in calling that out in
the website. That better air was important to all of us, but if we wanted to address these
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disparities, which was what would get people’s attention, here were some of the things that did
contribute to those inequities. Jeannette agreed that air pollution may be causing some of the
disparities, but there were other things that were contributing to that, too, such as health
equality, poverty and various other things.
Greg Pratt explained that fine particles, PM2.5, were quite uniform spatially, and it was a rather
gross measure of air pollution. When we have had high PM2.5 levels, we generally have had
transported air that was mixed, so there was a uniform air mass across the metro area, with
uniform concentrations. But there were other measures of fine particles and other measures of
air pollution. Current thinking was that even smaller particles, the ultra-fine and even
nanoparticle, were more responsible for health effects. Those particles were better transported
into the lower lung; they were better transferred into the bloodstream, so they could move
throughout the body. Greg continued that those very fine particles often occurred in very fresh
combustion processes. A classic example would be getting very close to car exhaust. The car
exhaust had gaseous, very fine particles, and as you moved just within a few feet of the
exhaust, those particles began to accumulate into larger particles. As you were breathing that
fresh exhaust, you would have a lot of very small particles easily transported into the body.
Also, they would have a lot of products of incomplete combustion if you had an internal
combustion engine, for example. You could see that occurring near busy roadways, right near
sources of air pollution. There was a disparities question there as well, because people with low
income and minorities tended to live near busy roads. Greg offered to share a paper in the
future that he had just published on this topic.
Jeanne Ayers commented that what she found interesting in the data was that in many areas of
prevention, when we implemented a universal preventive strategy, the benefit accrued
greatest to the communities who were most privileged. This was actually an opportunity to lead
with something where preventive strategies would benefit communities that were experiencing
the greatest health disparities. So this was a great opportunity to lead with prevention around
something that was going to make a bigger difference for a lot of people who were suffering.
Paul Allwood added that Jeanne had made an excellent point; he would just add that part of
the messaging had to be the idea of community, that everyone had concern and compassion
for everyone else; that everyone benefited when everyone benefited.
Tracking Updates and Program Evaluation
Matthew Montesano demonstrated the new Air, Health, and Poverty data visualizer on the
Data Access portal. Portal updates were provided in written form on pages 24-26 of the June 9,
2015 background materials book. Panel members were invited to ask questions and comment
on all updates.
Matthew began by giving some background: the CDC established the national tracking network
to look at environmental health changes and related health outcomes together, but often data
sets were examined separately. This data visualizer was part of a move toward “co-displays”
that showed related datasets together.
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With the joint work of the MPCA and MDH on the Air and Health Initiative, there was an
opportunity to put together a data visualizer to connect many different data sets on Air Quality,
Health and Poverty. Matthew explained that this data visualizer had been soft launched, and he
described the elements and how they worked together to show the relationships, the context
and the specifics of the data. Matthew thought MN Tracking had been the first in the tracking
network to develop this tool.
Greg Pratt commented that MPCA had been working on similar tools, and asked about the
software used for the site; Matthew responded that it was Primefaces and jqplot. Lisa Yost
wondered about the text that was on the page and whether it was associated with each of the
boxes checked. Matthew responded that the text was static, regardless of the selections, and
was an indication of known facts, as well as the definitions of terms found in the data. Lisa
thought it was a great program and wondered whether there was output for others to use the
data. Matthew said that for all the features that we are adding to the program, there was also a
table generated. There was not a download data button yet, but that would be added during
the next round of upgrades.
Mercury Impact Analysis for Informing Reduction Initiatives
Jean Johnson introduced a recent MN Tracking analysis of the economic burden of mercury in
newborns, an extension of the previous burden report on childhood asthma and lead poisoning,
thanking Frank Kohlasch and David Bael of the MPCA for their assistance in the project. Written
information on the analysis can be found on pages 27-37 of the June 9th advisory panel
background book.
Jean explained the purpose of the report, which was to provide health impact and cost
estimates to inform the public and policy makers about the scale and cost of children’s diseases
from environmental causes in the state. This can be used to track the progress of the programs
aimed at disease prevention in terms of costs, lives saved and diseases prevented. For the
tracking program, this also demonstrated the relevant use of the data for informing policy. The
original report was a collaboration of several states, each using similar methods to come up
with their estimates. The Minnesota report was published in December 2014, entitled
“The Economic Burden of the Environment on Two Childhood Diseases: Asthma and Lead
Poisoning in Minnesota”, and is available on our website. We are one of two states who have
published the report.
We chose mercury as our chemical of interest since methylmercury toxicity was second only to
lead in the national statistics looking at contributions to pediatric environmental illness; it was
estimated to be a $5.1 million cost by Landrigan. It was also an important issue for Minnesota,
highlighted by the pilot study done in Lake Superior that showed elevations in prenatal mercury
exposure in the state, and we were now conducting biomonitoring work with the MN FEET
project. MPCA has a very active program working on mercury reduction and the state also has a
very active fish monitoring and fish advisory program.
Blair Sevcik reviewed the methods used for the analysis of prenatal mercury exposure (found
on pages 30 –36 of the June 9, 2015 background materials book):
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Economic Burden: Disease counts x cost per case x environmentally attributable fraction (EAF)
where Disease/case counts = average mercury level; Cost per case = lost lifetime earnings due
to IQ deficit; and EAF = 70%
Environmentally attributable fraction (EAF) was the “portion of a particular disease that would
be eliminated if environmental factors were reduced to their lowest feasible levels”. In other
words, an EAF of 70 percent meant that 70 percent of mercury toxicity cases, where elevated
mercury caused IQ deficits, could be prevented if mercury of human origin in the environment
was reduced to the lowest possible level.
Blair explained that there was not a representative sample of mercury levels in Minnesota
newborns or women, so they had used the most recent NHANES sample of childbearing-aged
women as a proxy for pregnant women and a newborn’s exposure to mercury during brain
development. They measured average mercury levels in women that had a level above a
threshold.
The prenatal mercury exposure method used was similar to the childhood lead poisoning
method from our 2014 burden report. Similar to lead, we measured an IQ deficit as a result of
mercury exposure and the subsequent loss of lifetime earnings. But, mercury method differed
in three important ways: 1) The EAF was less than 100% for mercury; 2)We measured mercury
levels above a reference level rather than measure any level above zero; and 3)We used
national biomonitoring data as opposed to the MN surveillance data we had available to us for
lead.
Before she showed the data tables, Blair explained where the threshold of 3.4 micrograms per
liter had come from (5.8 micrograms of mercury per liter of cord blood). Research has shown
that the average ratio of mercury in newborn’s cord blood compared to maternal blood was
1.7. So mercury levels were 1.7-times higher in a newborn than in maternal blood. Studies have
converted the EPA reference level cord and arrived at a threshold of 3.4 micrograms per liter in
women of childbearing age to estimate the number of newborns affected by elevated mercury.
Blair then recapped tables 1-3, the results and the limitations of the analysis, found on pages
31-36 of the June 9th background materials book. The next steps, she explained, were to ask
the Advisory Panel, Minnesota Pollution Control Agency and other stakeholders for input on
this report’s value and how it would be used; explore the differences by race/ethnicity (since
we had national data on race/ethnicity from NHANES) and expand upon policy implications (for
example, addressing not just the policy implications in Minnesota, but also that global
emissions of mercury played a huge role in Minnesota) and create a public friendly report using
this more scientific report as a basis—to accompany the 2014 burden report.
Greg Pratt wondered whether there had been a consideration of using a 100 percent EAF or
had the 70 percent been used right away. He added that exposure was going to vary by
geography and diet, so was there evidence that there were IQ effects at 3.4 or even lower. He
continued with the observation that there were also natural sources of lead in the
environment, but 100 percent EAF had been used there. He was wondering whether a similar
argument could have been made for using 100 percent EAF for mercury. Blair responded that
with lead, there was no safe level, but with mercury, we followed a published method and that
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method assumed a safe exposure level and an EAF of 70%. This had also been supported by two
Minnesota papers. Greg commented that the economic impact would be higher if you assumed
a different percent. Blair agreed.
Next, Frank Kohlasch, Section Manager of the Environmental Analysis & Outcomes Section at
the Minnesota Pollution Control Agency, gave a brief presentation on “Actions Addressing
Mercury in Minnesota’s Environment” which can be found on page 37 of the June 9, 2015
Advisory Panel background materials book. He recognized the value of the analyses done and
discussed the economic burden of mercury, especially in informing the value of proposed
reduction efforts.
Frank described Minnesota’s leadership in the plan to reduce mercury releases in the state by
2025; the mercury pollution control process at coal plants. He stated that in Minnesota the
impacts were significant. Frank also discussed the biggest challenge of finding better ways to
intervene in the mercury being released through the waste and recycling stream, due to there
being multiple sources of mercury (attributed to human-caused activity).
The following questions were presented to the panel:
•
•
•
How can MDH-EHTB continue to support and inform the MPCA’s mercury reduction
initiatives?
Given the limitations, how well does the economic burden analysis serve its
intended purpose?
What additional information would be most helpful going forward?
Discussion
Lisa Yost wondered how representative NHANES was of Minnesota. She added that if what we
had done at MPCA had been effective, then it could be lower than the national numbers. Blair
responded that it would definitely be useful to measure mercury levels in Minnesota women
or, better yet, Minnesota newborns, but we only had a national estimate. Also, MN
Biomonitoring has focused on at-risk groups, so it was not representative of the state. Jean
Johnson said that the national data does not always represent Minnesota; there are disparities.
Frank Kohlasch added that Minnesota had more subsistence fishing, so exposure issues could
be higher, but that did not mean that the mercury emission policies had not been successful.
We could show that they have been effective. In answer to Greg Pratt’s question about
whether the Public Utilities Commission had set an externality value for power plants that they
regulate, Frank replied that they had not and mercury was not one of their considerations at
this time.
Geary Olsen commented that the economic analysis was based on Landrigan’s paper, which
was 12-14 years old at this time; were there any more up-to-date papers on this, since it plays
such a major role in your economic burden equation? Blair replied that Trasande’s 2011 paper
had used the 2002 Landrigan paper for its equation to calculate economic burden; also, it had
repeated the 2002 paper’s estimate of IQ deficit on earnings. Geary suggested a review of
Landrigan’s numbers to see if they were reliable. Blair agreed to look into this. Lisa Yost added
that it seemed so tenuous that a single point deficit in IQ could make such a difference in
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lifetime earnings, especially in such a linear fashion. There had been a different way to calculate
it for lead, but not for mercury, Blair responded. She agreed to explore categorical IQ deficits
based on mercury ranges.
Lisa Yost thought that in conveying this, the first talking point had to be that it was based on
NHANES. That based on NHANES, Minnesota might be experiencing this. Jean Johnson added
that they had discussed whether to reanalyze this based on the newborn levels from the four
groups we would have at the end of the MN FEET project. Separately, NHANES contained racial
data, and there had been discussion about reanalyzing this across different groups.
Melanie Ferris wondered about mercury accumulation and whether some mercury does leave
the body? Jean responded that the half-life was 60 days for methylmercury. Paul Allwood
wondered if that were true about all forms of mercury. Melanie said the policy implications for
annual checkups and medical appointments for women of childbearing age might be handled in
a different way.
Jean said the message regarding fish consumption was tricky, specifically on the effects of
higher levels of mercury. The main message was to encourage people to eat fish, but it was a
balancing act because the benefits of fatty acids sometimes outweighed the risks of mercury.
Jim Kelly agreed that the effects were more concerning at higher levels of exposure than lower
levels of exposure, which was where the benefits of eating fish were going to outweigh the
risks. These messages needed to be balanced very carefully. They wanted to encourage people
to eat fish, because it was a great source of protein and it had lots of other nutrients that were
good for moms and for kids, so they did not want to scare people off from eating what, for
them, was a healthy source of protein.
Melanie Ferris was curious about what kind of feedback had been received from the report on
asthma and lead; who had been using it and how. Blair responded that in March they had
presented a well-attended webinar focused on the lead portion of the report. The Healthy
Homes and Lead Poisoning Prevention Program planned to use the cost of lead poisoning from
that report for future reports. Asthma had shared the report widely with all their stakeholders
and there had been interest, but Blair was not sure of any actions or media response at this
time. Jean Johnson added that funding had been restored for blood lead and for asthma.
Melanie liked the webinar idea as a distribution strategy, since it allowed for some back and
forth in clarification of details of the report. She believed it was another great tactic in getting
the word out to stakeholders.
Hearing no public comments or questions from the audience and no new business, the meeting
was adjourned at 3:50 pm.
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