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By Michael D. Shaw, Contributing Columnist - HealthNewsDigest.com
Apr 27, 2008
(HealthNewsDigest.com) - It started a few months ago with
the FEMA trailers. Elevated levels of the chemical were discovered in some of
them, and the beleaguered agency found itself mired in another public relations
disaster.
The problem is, it's very difficult to get away from formaldehyde! Look anywhere
in your home or workplace—at the wood products, paint, drapery, carpets, paper,
and insulation materials—to name just a few items. They all contain
formaldehyde, a colorless, pungent-smelling gas that can trigger numerous nasty
health effects. Relatively low concentrations of formaldehyde can cause searing
eye irritation, skin rashes, and a host of respiratory symptoms.
As to the trailers, the source was very likely excessive outgassing from
manufactured wood products—including particleboard and medium density
fiberboard—where formaldehyde is an important component in the very adhesives
that hold them together. To be sure, since 1984, in accordance with 24 CFR
3280.308 [Manufactured Home Construction and Safety Standards], the Department
of Housing and Urban Development (HUD) has promulgated regulations limiting
formaldehyde emissions in plywood materials to no more than 0.2 ppm
(parts-per-million) and in particleboard materials to no more than 0.3 ppm, when
installed in manufactured homes.
Experience has shown that these levels, mixed in the general air of the
manufactured home, will normally keep emissions below 0.01 ppm. One can only
speculate how, in the rush and crush of the Katrina disaster, non-compliant
materials ended up in the trailers.
Other standards include:
Since the benzene scare of the late 1970s, regulatory
levels for most chemicals are decidedly conservative, with numerous layers of
safety factors built in. Moreover, it is often the case that when
epidemiological studies are done that compare a cohort with documented exposure
to a particular compound versus the "normal" population, morbidity and mortality
for the conditions being considered are about the same. No doubt, absent
occupational health regulations, the picture would not be quite as rosy.
Sometimes, though, the cool light of reason can become eclipsed by hysteria,
especially at the hands of those who would profit—namely plaintiff's attorneys
and media outlets that thrive on sensationalism.
In the wake of FEMA's troubles, numerous websites appeared promising big money
relief from "toxic trailers." It is well to remember that the regulatory levels
are based on a lifetime of exposure, and it is unlikely in the extreme that
short-term exposure to formaldehyde could have any lasting effects. But then,
over a billion dollars was paid out in judgments regarding silicone breast
implants, despite contrary evidence in dozens of technical papers. To add insult
to injury, the FDA lifted its ban on the implants some years later.
Of course, the FEMA trailers have been in the news constantly, but a new low was
struck when one of the TV networks deliberately misquoted a FEMA official who
was warning his employees about entering unoccupied trailers, that had been
parked in a lot. This was spun to make it look like the agency thought it was OK
for the hapless residents to enter trailers, that FEMA itself was afraid of.
On April 11th, FEMA took the bold step of setting new procurement standards for
all future temporary housing units purchased by the agency, including a
requirement that each unit must test below 0.016 parts per million (ppm) [16
parts-per-billion]. Supposedly, this number is based on Centers for Disease
Control and Prevention (CDC) data that pegs indoor air concentrations of
formaldehyde in the range from 10 to 30 parts per billion (ppb).
However, we must note that formaldehyde is a normal component of human
metabolism, and there are measurable amounts of formaldehyde in human breath at
all times. A paper from 2005 found a median level of 4.3 ppb, with levels
detected as high as 73 ppb. Subsequently, a 2008 paper suggests that the
technology used in the earlier breath measurements understated the
concentrations, and that the median level should be more like 10 ppb.
How prudent is it to set ambient air regulations so close to metabolic levels?
Finally, the blogosphere and conventional media are all atwitter over results
presented last week at the American Academy of Neurology Meeting in Chicago.
Marc Weisskopf, of the Harvard School of Public Health, reported that
formaldehyde exposure correlates with an increased risk of contracting
amyotrophic lateral sclerosis (ALS—Lou Gehrig's disease). Ironically, the
researchers were looking for a pesticide/herbicide connection and were unable to
find one, so they focused on other compounds.
At best, though, Weisskopf's findings are premature. They were based on the
subjects' self-assessment of exposure—a notoriously inaccurate method.
Beauticians most frequently reported on-the-job formaldehyde exposure (24.6%),
followed by pharmacists/morticians/chemists, radiological and lab technicians,
doctors and veterinarians, dentists, photographers and printers, and nurses
(6.6%). This is a far cry from actual quantitative formaldehyde concentration
exposure data.
In addition, this formaldehyde cohort comprised only 2.6% of the total
population under study, with small numbers of individuals in several of the
occupations examined. Weisskopf did acknowledge these and other limitations of
his study. A follow-up effort should be done comparing a cohort of individuals
with documented exposures to a reasonable control group before conclusions are
drawn.
Just don't expect the doom profiteers and fearmongers to agree. Meanwhile, the
number one preventable cause of morbidity and mortality—obesity—is given scant
attention, compared to the media's preferred scare-of-the-month.
"You just can't beat the person who never gives up." Babe Ruth
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© ALS Independence 2003-08