
Toxic fluorinated compounds found in drinking water of 33 states - chmaynard
http://news.harvard.edu/gazette/story/2016/08/unsafe-levels-of-toxic-chemicals-found-in-drinking-water-of-33-states/
======
latimer
Previous discussion here:
[https://news.ycombinator.com/item?id=12265762](https://news.ycombinator.com/item?id=12265762)

Top comment has instructions for finding the results for your ZIP code.

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philipkglass
This article is about heavily fluorinated organic compounds -- molecules with
a carbon skeleton and all or most of the hydrogen atoms replaced by fluorine.
These are not the ionic fluorine compounds that protect teeth against decay
(and that cause acute toxicity in case of over-consumption).

 _Why are these compounds hazardous?_

\- Harmful biological effects in the human body, like hormone-mimic activity.

\- Low molecular polarity leads to bio-magnification in fats and oils up
through the food chain, and persistence in human fat.

\- The high strength of the carbon-fluorine bonds greatly reduces the rate at
which typical environmental degradation mechanisms (hydrolysis, photolysis,
atmospheric oxidation, enzymatic breakdown in cells...) act on these
compounds, compared to their hydrocarbon counterparts.

 _Why are these compounds used?_

The same properties that make them hazards once dispersed -- strong carbon-
fluorine bonds that resist breakdown, low polarity -- make them desirable in
applications where people want water-repellant surfaces or materials that
resist high temperatures and/or chemical attack.

 _Why weren 't the risks better known before?_

It's a lot easier to test for acute hazards than for chronic ones. By _acute_
toxicity metrics, like feeding a bunch of rats these compounds until the dose
is high enough to kill half, these materials are generally less toxic than
substances like potassium fluoride. It turns out that for low level _chronic_
exposure, perfluorinated compounds are more hazardous than simple ionic
fluorides due to persistence and accumulation.

The link between stability and persistence makes up a recurring theme in
environmental toxicology: materials with lower acute hazards are often worse
hazards in the long term. The very lack of reactivity that makes molecules
less acutely hazardous in case of e.g. a fire or a worker accidentally
splashing some on skin makes them _more_ likely to be long term problems,
because the same basic properties impair how quickly environmental sinks can
break them down. Pure methanol ignites more easily than diesel fuel and has
worse acute toxicity risks if a worker gets drenched in a spill. But diesel
contamination from a leaking storage tank is more persistent.

~~~
SomeCallMeTim
The article doesn't mention whether or not these compounds are removed by
using a filter (like a Brita filter).

I know Brita filters don't remove fluoride normally, but these compounds sound
organic, which activated carbon usually _does_ remove. Any idea whether
standard filters remove this?

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KSS42
This EPA page seems to imply that activated carbon would help remove it:

[https://www.epa.gov/ground-water-and-drinking-
water/drinking...](https://www.epa.gov/ground-water-and-drinking-
water/drinking-water-health-advisories-pfoa-and-pfos)

\---------------- Can PFOA and/or PFOS be boiled out of my water?

No; PFOA and PFOS cannot be removed by heating or boiling water. However,
there are steps you and your drinking water system can take to limit your
exposure.In some cases, drinking water systems may be able to reduce
concentrations of perfluoroalkyl substances, including PFOA and PFOS, by
closing contaminated wells or changing rates of blending of water sources.
Alternatively, public water systems can treat source water with activated
carbon or high pressure membrane systems (e.g., reverse osmosis) to remove
PFOA and PFOS from drinking water. These treatment systems are used by some
public water systems today, but should be carefully designed and maintained to
ensure that they are effective for treating PFOA and PFOS. In some
communities, entities have provided bottled water to consumers while steps to
reduce or remove PFOS or PFOA from drinking water or to establish a new water
supply are completed.

Home drinking water treatment units are typically certified by independent
third party organizations against ANSI (American National Standards Institute)
standards to verify their contaminant removal claims. Some home filters remove
impurities using activated carbon and reverse osmosis, which are the same
technologies utilized by public water supply systems to remove PFOA and PFOS.
However, there currently are no ANSI protocols for testing home treatment
systems to verify that these devices effectively remove PFOA and PFOS or how
frequently the filters should be changed in order to maintain removal
efficiency. NSF International is currently developing such protocols.

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esun
The article refers to compounds found in, for example, firefighting foam and
not to the fluoride added for preventing tooth decay.

~~~
hughes
Nevertheless, this study will be added to the arsenal of those seeking to end
municipal fluoridation.

~~~
throwaway91111
Mouthwash seems like a better option than drinking fluoride to improve teeth.

~~~
djsumdog
Very true. I've been to some of the anti-fluoride talks and read a lot on both
sides.

From what I gather, there simply isn't enough fluoride added to water to
really make a difference. Add enough and you start getting dental floursis.

The people against municipal fluoride use a lot of the same bad maths to link
fluoride to a plethora of ailments. Their evidence doesn't really add up
either. Overall it looks like it's a wash.

I err on the side of it not being in water. It doesn't really help teeth
unless applied topically in high concentrations, so we're better off spending
money to give kids free toothpaste/brushes/education.

There's the question as to whether or not it can lead to things like
osteoporosis, and honestly that question can't be answered easily. Long term
toxicity buildup over 30~40+ years in humans is very difficult to test and
control for. You can't put humans in a cage and have one group only drink
water with fluoride and the other not. Our primate counterparts simply don't
live long enough. People move around too much and drink too many different
types of drinks to accurately survey exposure.

Of course this article is not about fluoride in water, so this is kinda a
rabbit trail comment anyway.

~~~
yuhong
It would be even better to decrease the consumption of sugar I think.

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the_gastropod
Luckily this will all be fixed by Scott Pruitt, by getting rid of silly safety
limits (read: business killing regulations) all together! </s>

~~~
general_ai
Your comment would hold a lot more weight if EPA or some other massive
government agency found it possible to help people in Flint, MI, which did not
have drinkable water for years now, and still don't have it.

~~~
diogenescynic
The EPA and other regulators have been hamstrung by republicans since their
inception and then when they don't do everything perfectly republicans love to
show how the EPA, SEC or whoever aren't doing their job. Republicans sabotage
these regulators and don't provide adequate funding. It's sabotage. "The
Republicans are the party that says government doesn't work and then they get
elected and prove it." \- P. J. O'Rourke

~~~
general_ai
FYI, the EPA is comprised of 15000 employees, and its annual budet is $8.14B.
That's $543K per head. A lot of money for sitting on their hands and making
excuses that they're "hamstrung".

~~~
knz
That is a poor metric. The EPA funds many pollution prevention and mitigation
programs that far exceed the cost of staffing.

~~~
general_ai
Nonetheless, people in Flint didn't have drinkable water for years. If the
agency is so toothless with a highly politicized case like this, you can only
imagine how toothless it is when it comes to the less publicized cases. So
don't tell me how awesome the EPA currently is. Maybe it could, in fact,
benefit from a swift kick in the ass.

~~~
jolux
They can't do anything with the funding they have, so maybe they'll do better
with less funding? That's a non-sequitur.

~~~
general_ai
Maybe it's not about funding at all?

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overcast
While drinking water is generally extremely safe in the US, especially
compared to many other countries of the world. I still install three stage,
under the counter filtration systems for any kitchen tap water. Minimal costs,
and at the very least prevents the water from tasting like a pool.

~~~
Reason077
Exactly! Everyone's always so worried about fluoride in drinking water, with
little justification and without giving a thought to all the chlorine which is
often present in far greater concentrations and, in certain conditions, can
react with other organic and inorganic compounds to form all sorts of nasties.

Get a good filter for your drinking water and most of these concerns vanish.
Plus you'll save a fortune on bottled water.

~~~
ggcdn
If you're worried about chlorine, you don't even need a filter. Put the water
in a jug in the fridge for an hour or so.

~~~
Reason077
Free chlorine will indeed break down over time, but an hour in the fridge
probably won't be sufficient - the half life of free chlorine in water is much
longer than an hour! (In sunlight or UV, however, it'll break down much
faster).

Secondly, Chloramine is now often used instead (or in addition to) free
chlorine. Chloramine is more stable and won't break down by putting it in the
fridge.

And the potential health issue isn't so much with chlorine itself anyway, but
with other chemical products that can be formed by reactions with chlorine,
possibly before the water even reaches your tap.

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herbps10
I work with one of the authors of the Hu et al. paper that this article is
based on. I'm happy to relay any questions people have to her.

~~~
lawpoop
I'm not in any way advocating for toxins in the water supply, but do you worry
that news like this will embolden anti-flouride people?

~~~
AnimalMuppet
If I understand correctly, I'd rather have cavities than cancer.

That is: Flouride is supposed to help prevent tooth decay. This stuff, on the
other hand, "has been linked to" cancer (how strongly, I'm not sure). But if
warning about a cancer-causer kills flouridation as collateral damage, well, I
prefer that to the other way around (not doing anything about the cancer-
causer to protect people's teeth).

~~~
loblollyboy
This is extremely non-scientific, but I am an american living outside of the
us - and I often wonder 'what's wrong with us' when I meet Americans. Maybe we
just have it too easy, maybe we don't have to open up our minds to other
cultures (we are the dominant one). But I've met enough people that just make
me think c'mon man! That said, we're the dominant culture for a reason - we
have some super talented people. At the end of the day, 'flouride' probably
isn't the root-cause of our 'unique'-ness.

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refurb
_had at least one water sample that measured at or above the EPA safety limit
of 70 parts per trillion (ng /L)_

Just for reference, here are the EPA safety limits for other chemicals....[1]

Cyanide - 200,000 ng/L

Lead - 15,000 ng/L

Mercury - 2,000 ng/L

Benzene - 5,000 ng/L

Glyphosate - 700,000 ng/L

PCBs - 500 ng/L

[1][https://www.epa.gov/ground-water-and-drinking-water/table-
re...](https://www.epa.gov/ground-water-and-drinking-water/table-regulated-
drinking-water-contaminants)

~~~
sndean
Not really related, but even as a scientist I really don't understand how ng/L
== parts-per-trillion. I know that's a correct conversion, but it doesn't
doesn't make much sense. I guess that's why part-per notation are called
pseudo-units.

A more substantive comment:

Some of these are particularly scary, especially if you have a job where
you're potentially exposed. For example, for benzene has a pretty strong odor,
but 5000 ng/L is supposedly 1000 times below what you're able to smell. And
it's a carcinogen...

~~~
daveguy
The L part is assumed to have density of 1 (kg/L) and therefore be 1kg mass
(mostly water). 1 kg = 1 trillion ng. Because the vast majority of the sample
is water the number of nanograms of the substance per nanograms of water is
approximately the number of parts per trillion. As you get into higher
concentrations of solute you have to consider density of the solute and water
as separate parts. In the ng/L or ug/L range you can hand wave the L as 1
trillion parts (by mass) and the ng as the parts out of a trillion in the full
volume of sample.

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08-15
Nice, an article that links to sources in the prrimary scientific literature!
Let's see, the link text says "potent immunotoxicants", that's probably a
study about the effects of PFAS on the immune system. But no, it's actually
some meaningless bullshit about evolution and doesn't even mention the word
"fluor" once.

Given that, the term "toxic" is unjustified (it appears that if PFOA is toxic,
then so are fatty acids), and so is the claim of "unsafe levels". This is
sensationalist bullshit.

~~~
matt4077
Your misunderstanding starts where you're considering the linked article a
"primary source". Even though it's at harvard.edu, it's not a peer-reviewed
"primary source".

Given that the absence of evidence does not constitute evidence of absence,
the conclusion and causation you imply with "given that" is wrong.

You're also awfully quick to call stuff you don't understand "bullshit".

~~~
08-15
What, are you saying they _didn 't_ link to a scientific source at all?! I'm
shocked, shocked, I tell you!

The point was that this is bullshit precisely because it pretends to link to a
scientific source, but doesn't. Sure, it's still _possible_ that every single
word in the article is correct even in the absence of actual research---but is
it _likely_?

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sageikosa
The study found that PFASs were detectable at the minimum reporting levels
required by the EPA in 194 out of 4,864 water supplies in 33 states across the
United States.

So, about 4% of water supplies had something at the minimum reporting levels;
which must be above the detection limits, but may not be at action levels. I'd
probably be more worried about heavy metals and organics in some of those
locations than fire-fighting foam, but I drink groundwater, not surface-based
treatment plant water.

~~~
maxerickson
Wells near contamination sources may also be contaminated (they just get less
monitoring than municipal supplies).

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chmaynard
My father was a Ph.D. organic chemist who worked for DuPont at the
Experimental Station in Wilmington, DE. We admired and even loved DuPont while
I was growing up there in the 1950's and 60's (the "Better Living Through
Chemistry" era).

Now I am learning the sad truth about DuPont (and many other industrial
chemical manufacturers). Despite the many great achievements of their
employees, DuPont was a diabolically evil company. The history of their GM
partnership and their promotion of tetraethyl lead in gasoline alone is
justification for this statement.

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anu7df
here is a better interactive map. [http://www.ewg.org/interactive-
maps/2015-teflon-chemical-har...](http://www.ewg.org/interactive-
maps/2015-teflon-chemical-harmful-at-smallest-doses-lower-48.php)

~~~
cialowicz
This is pretty interesting, thanks.

I'm not really strong in stats, but it seems like many of the non-contaminated
counties have very low sample sizes that may not be statistically significant.
Example: in Marin County, 0 of 11 samples were found to be contaminated. In
Alameda, 2 of 73 samples were contaminated.

Maybe someone else can comment?

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tibbon
Why isn't the state of our water supply a national emergency? In the long term
this will affect far more people than whatever terrorist scare Trump is
currently worried about.

~~~
e40
The short answer: Republicans. They want less regulation and have been trying
for decades to gut the EPA. They will finally get their chance.

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The_ed17
Does anyone have a better map? Would like to see if I'm in the highlighted
range or not - I'm pretty close to one.

~~~
atarian
Your city/county might provide a water quality report on their official
website which may include a more specific map.

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costcopizza
So what supplement should I buy and take to hedge against this risk?

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juvinious
"They are making the freaking frogs gay!" \--- Alex Jones

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wnevets
They're not toxic, they're just alternatively healthy.

