Anyone who pays attention to
U. S. news these days cannot be blamed for assuming that
bipartisanship—specifically, the joint sponsorship of bills by both Democrats
and Republicans—is ancient history, maybe even to the extent that they’ve
installed separate Democratic and Republican bathrooms at the Capitol. But a small glimmer of bipartisanship came
last Friday when seven Democratic senators and an equal number of Republicans
introduced a bill to classify a group of chemicals known as PFAS as toxic and
worthy of Superfund cleanup efforts. And
the newly named chief of the U. S. Environmental Protection Agency, Andrew
Wheeler, says he’s going to do something about PFAS, and has received both
grudging approval on the part of opponents of the current administration and
criticism that what he’s proposing doesn’t go nearly far enough.
Maybe you already know all
about PFAS, but I didn’t, so here’s a brief summary of what they are and why
they’re in the news.
Fluorine is the most
chemically reactive of the halogens, a group of elements in the periodic table
that includes chlorine, iodine, and bromine.
Fluorine is the faithful-forever element: whatever fluorine bonds to tends to stay bonded
to it. So chemicals made with fluorine
substituted for chlorine, for instance, tend to be very stable and last forever
unless you put them in high-temperature incinerators, for example.
One of the most familiar
chemicals that use fluorine is polytetrafluoroethylene, known more widely under
the trade name Teflon. Shortly after the
discovery of Teflon and related fluorinated compounds after World War II, they
were hailed for their stability and apparent lack of toxicity. Besides Teflon, chemists found that they
could make effective and long-lasting surfactants with a group of fluorinated
chemicals that are known by the general name of PFAS (perfluorinated alkylated
Surfactants are used in
detergents to dissolve grease in water solutions and also to change the way
surfaces react to water. Typically, a
surfactant will be a longish molecule with a hydrophobic end that likes to be
in oil, and a hydrophilic end that likes to be in water. You may have seen an experiment in which you
put a few drops of oil on the surface of water in a clean pan. The oil forms round bubble-like globules with
sharp boundaries. Then putting just a
tiny amount of dish soap in the middle of the pan will cause the oil droplets
to run away toward the edge of the pan like pigeons when a cat shows up. PFAS compounds form long-lasting foams and
have been used in firefighting foam for years.
Trouble is, owing to their
persistent chemical nature, these compounds don’t biodegrade. And because they are easily dissolved and
travel in water, they are found in drinking water in many states and have been
detected in the blood of newborn babies.
And that isn’t good, because the U. S. Centers for Disease Control says
that PFAS chemicals are implicated in a number of adverse human health effects,
such as increased levels of cholesterol and cancer, lowered fertility in women,
and interference with physiological development in children.
The U. S. military was one
of the biggest users of PFAS, as the military specification for fire-fighting
foam used for petroleum fires virtually required the use of PFAS in it. Over the years, manufacturers have discovered
that the stuff accumulates in humans and have begun phasing it out voluntarily,
but that does nothing about the tons of it that is still lying around wherever
firefighting teams have practiced using foam, which means hundreds of both
civilian and military locations all across the U. S.
So what’s to be done? Well, recognizing the problem is the first
step, and that seems to be happening now.
The hazards of PFAS to humans are not as clearly defined as we’d like
them to be, but they’re sufficiently serious that major steps to remediate PFAS
contamination are justified. And that’s
just what the PFAS Action Act of 2019 would do.
Designation of a place as a Superfund site means federal dollars are available
to clean it up, even if it means digging up tons of soil and running it through
an incinerator or equally extreme and costly measures. The fact that an equal number of Republican
and Democratic senators have joined forces on this measure is a rare sign that
there are still a few things that the parties can still agree on.
Practically speaking, the
chemicals have lost whatever commercial sponsorship they may have had, as their
U. S. manufacturers have abandoned them, hopefully for chemicals that are of
comparable effectiveness while being less toxic. I don’t know what happens when you try to
fight a fire with Dawn dish soap instead of PFAS foam, but things probably
don’t go as well. Nevertheless, it’s the
nature of technologists to learn from their mistakes and make improvements, not
only in the direct performance of the product, but in what happens to it after
it’s used and what it does in its so-called afterlife.
A particularly sad aspect of
this story is that while firefighters know they are going into a risky
business, running into burning buildings while everyone else is fleeing, they
may not have been fully apprised of a more subtle hazard associated with their
calling: the hazards of being exposed to
all kinds of nasty chemicals that are present in both fires and in firefighting
chemicals. Many burning plastics give
off very carcinogenic chemicals, and that is one reason why cancer has been the
leading cause of death among U. S. firefighters since 2005, according to a 2017
report. Not only do they deal with
carcinogens in fires, they’ve been unwittingly spreading toxic chemicals around
every time they use foam to put one out, too.
This is probably more about
PFAS chemicals than you perhaps wanted to find out. But every now and then it’s good to see that
the system—science, technology, government—does still work. Maybe not as well as it could or as fast as
it could, but we’ve identified a problem in PFAS chemicals. U. S. companies have quit making them,
lawmakers are agreeing to do something about them, and the rest of us can go on
about our business knowing that at least one matter of concern is getting some
kind of coordinated attention.