Public concern over airborne metals and chemicals has been
recertified as a hot-button health issue.
The Dallas Morning News ran a 1,200-word story in
January on how close to an Exide Technologies lead recycling
smelter the state may locate its monitoring equipment for air
toxics, a tug-of-war that highlights the mundane headaches
required to collect actual data.
But what if there were a secret technique to avoid all of
that messy stuff?
Voila! Click on to USA Today's Web site and you
will find a fascinating database accompanying a series titled
"The Smokestack Effect: Toxic Air and America's Schools." The
database provides information on the five worst air pollutants
estimated at each of 128,000 schools and the five polluters
most responsible for those toxics, along with a good-to-bad
According to a first-place award citation in February from
the National Institute for Computer-Assisted Reporting, the
USA Today reporters "gathered tens of millions of air
quality and industrial pollution records" and "then used the
Environmental Protection Agency's own pollution model to
identify thousands of schools where the air was far more toxic
than in nearby neighborhoods."
Unknown is whether there was any discussion at the institute
over whether the citation should be lengthened slightly to
include inserting the words "likely to be" just ahead of "far
As a reality check, the newspaper also sponsored actual air
sampling at nearly 100 schools, although there was no
systematic way to use those samples to modify the
128,000-school model. The direct measurements showed that the
Tennessee school modeled as the worst in the nation received
much less contamination than had been projected.
The on-site data showed "levels of manganese thousands of
times lower than what the model estimated would be in the air."
The nearby manufacturing plant that uses manganese explained
that the waste metal ends up embedded in shards of steel that
are swept up from the shop floor and discarded. If that
information is correct, the material shouldn't have been coded
as manganese emitted into the air. Whether it should have been
reported to the EPA as manufacturer waste at all is a separate
It would be poetic justice for someone to create a scorecard
evaluating the newspaper's smokestack project. That's unlikely
to happen. The reason is cost.
After the newspaper ran its series, the EPA launched a
school air toxics project of its own, taking actual
measurements. For a limited period, readings are being taken at
63 sites at a cost of $2.5 million, or about $39,680 per
Assuming the unit cost could be halved with greater scope
and that a 5-percent sample of schools nationwide would
suffice, the cost of evaluating "The Smokestack Effect" would
be $127 million. And that's without reimbursing state
environmental agencies for the staff time needed to retrieve
and replace filters and administer the programs. The EPA's
current $2.5-million payout only covers equipment and
USA Today's effort is impressive for intellectual
elegance in its mingling of sources. The question is how close
does the methodology it embraces square with actual
measurements and real-world conditions?
Essentially, "the Smokestack Effect" constructs a virtual
world from the limited facts available plus an intricate
structure of modeled assumptions. "For each square kilometer,
the model produces an estimate of which chemicals were in the
air, where those chemicals came from and how harmful they might
be," said USA Today reporters Blake Morrison and Brad
Heath. USA Today's final ingredient was a roster of
exact school locations, cobbled together from two dozen or so
A limited reality check for USA Today's modeling
will become available within the next year. As it turns out,
four of USA Today's 10 worst sites are covered by the
EPA measurement program still taking place. One score is
already in: the Tennessee school that ought to have had a
manganese problem but didn't.
The EPA does an annual Toxics Release Inventory that puts
plant-level data into the public domain. The agency also
sponsors a software product called Risk-Screening Environmental
Indicators, which pulls together risk ratings for each toxic
with geographic modeling of air emissions.
Whatever its shortcoming may be, the Risk-Screening software
has been evolving since 1991. That allows the developers to
respond to feedback, to make changes when users spot
shortcomings. The alternative of doing real measurements, aside
from being expensive, is subject to Murphy's Law.
The EPA acknowledged recently that an equipment problem
messed up readings at 24 of the 63 schools in its current
project. It seems the timer that triggers the "off," after 24
hours of "on," was leaking its own chemicals into the filter
The orthodox solution would be to send the device back to
the EPA for repair. However, some state and local agencies,
doing the grunt work, chose a low-tech fix: they removed the
timer. On two successive days, at the same hour, a staffer went
to the problem site. First visit: Turn the gadget on. Second
visit: Turn the gadget off and remove the canister.