
Scientists cut the tolerable intake of PFAs by 99.9% - laurex
https://massivesci.com/articles/chemical-exposure-pfas-water-food
======
DenisM
I think this might be more informative:
[https://www.doh.wa.gov/CommunityandEnvironment/Contaminants/...](https://www.doh.wa.gov/CommunityandEnvironment/Contaminants/PFAS#PFAS%20in%20Drinking%20Water)

Also the headline overstates the content of the article by two orders of
magnitude - article suggests 10x change to safe level while the headline
stipulates 1000x.

------
exitcode00
Don't look now, but PFAs have been "replaced" with a chemical called "GenX."
These companies will just shapeshift their toxic sludge every time a major
suit is won. Sickening...

[https://en.wikipedia.org/wiki/GenX](https://en.wikipedia.org/wiki/GenX)

~~~
woolvalley
I wonder if all the 'compostable' bio plastics you see in utentsils and some
food packaging have the same problems or are safe.

~~~
iso1337
Most compostable bio plastics are made of Poly-lactic acid (lactic acid is the
stuff that gives that burning feeling in your muscles after a workout) from
corn.

PLA can compost in industrial sites, but (edit: add a not here) in normal
environments, perhaps that is the reason for your quote marks.

So at least the bulk of the material in the bioware is pretty safe, especially
when compared against PFA/PFOAs. That's not to say that it's impossible to mix
PLA with some other, unsafe chemicals.

~~~
contingencies
IIRC biostarch PLA can be produced from any industrial waste product high in
cellulose. In practice this would include for example sugar cane in addition
to corn husks. It is often said that they will completely degrade within 14
days in a warm vegetative compost environment. How closely a typical landfill
replicates this optimal, aerated environment is questionable. Anyway, they are
a lot better to have discarded around the planet than most plastic. The
problem is that they are extremely energy inefficient to produce.

Traditional polymers: Oil in, power in, cheap product out, correct disposal
and recycling required or planet suffers.

Biostarch polymers: Industrial waste in, huge amount of power in, comparable
but more expensive product out (but can be relied on to biodegrade eventually
if incorrectly disposed of).

The real solution is better food distribution systems with more efficient and
re-usable packaging and cutlery, so that disposal is not required.

~~~
iso1337
Yeah, re-use is always preferable. It often goes against ever-increasing
standard of hygiene.

It used to be common to collect used glass bottles and re-use them. That
practice still happens in countries like Thailand and Vietnam.

~~~
felix_nagaand
Still happens in America today. I refilled a glass jug at a local brewery
today. $5 deposit on a 750ml bottle, can return for the deposit or just leave
it in the car and get it refilled at just about any brewery, even some liquor
stores, restaurants and grocery stores.

~~~
contingencies
Better food distribution systems would also remove, for example, the need for
personal motor vehicles, personal grocery trips, spatially inefficient retail
spaces, the non-ideal refrigeration and other concerns deriving from food
safety concerns in such spaces, and even individual package labeling.

------
anonuser123456
For the parents in the audience, carpet is a major exposure path for young
children. Anything stain resistant (carpet/appulstry etc) has it (most
carpet). Abrasian from ordinary usage causes it to be released in the form of
dust. Toddlers, due to their proximity to the ground and propensity to put
their hands in their mouths, are particularly susceptible.

Better living through chemistry!

------
fencepost
As I understand it, most (all?) nonstick coatings on pans are chemicals in
this general category - some variant of fluorine compounds that hold together
well. The biggest problem particularly with older ones is that they start to
get less stable as heat gets higher - like it may if you leave an empty
nonstick pan over a burner, where it can give off fumes that are particularly
toxic to pet birds.

Avoiding those compounds likely accounts for at least some of the increased
trendiness of cast iron in the past decade or two, including the increase in
new "artisanal" cast iron makers like Stargazer, Finex, Butter Pat, Smithey,
Field Co and probably a few others (for reviews of a bunch of those, check out
Kent Rollins on Youtube). There's also quite a bit of information on
improving/smoothing less expensive cast iron.

~~~
jdhn
I looked at some of those brands to see what made them different from Lodge.
One had a different handle, while another one had a thicker bottom and thinner
sides for better searing, but they're also in the hundreds of dollars. A 12"
Lodge skillet is $40, that's at least half the price of the 12" skillets for
the other brands. For the price, I don't think that Lodge can be beat.

~~~
foobarian
I got a cheapo Lodge for this reason, but I wonder if the more expensive makes
add some postprocessing steps to smooth the casting. I found the rough Lodge
finish to be unworkable since food kept sticking, and it was hard to clean. I
ended up sanding it down to a glass finish and reseasoning it, and now it
works properly.

~~~
cauthon
How did you sand iron? (sorry if this is a naive question)

~~~
Retric
Same way you sand anything, as long as the grit is harder than what your
sanding it works just fine. Iron is only 4 on the Mohs Scale which is below
glass, so many types of sandpaper work fine.

------
ddebernardy
For fellow Europeans who are also wondering if this might affect them too, one
of the comments at the bottom of the article seems reassuring but is actually
somewhat misleading, because the precautionary principle wasn't a general
principle in EU law until late 2006.

That being said, the EFSA is looking into the topic:

[https://www.efsa.europa.eu/en/press/news/181213](https://www.efsa.europa.eu/en/press/news/181213)

------
StopClickBait
For those wondering

PFA/PFOS="poly- and perfluoroalkyl substances"

As an article seeking to get this message out about the PFA court case,
perhaps you are justified, however this should have been your starting point:

"The chemicals used as criteria in the suit are called PFASs (pronounced “pee-
fass”), and are unregulated at the federal level. [The suit asserts that these
chemicals are found in 98% of Americans today].

In June, the Agency for Toxic Substances and Disease Registry (ATSDR), an arm
of the Department of Health and Human Services (HHS) issued an updated draft
toxicological profile for PFASs.

For drinking water, [the report recommends an] acceptable concentration of 7
parts per trillion of PFOS and 11 parts per trillion for PFOA, according to
Laurel Schaider, a research scientist at the Silent Spring Institute. Right
now, the EPA’s 2016 guidelines set an acceptable drinking water concentration
for PFOA and PFOS at 70 parts per trillion, about ten times higher than the
draft report’s thresholds.

... by the standards in the ATSDR report, a PFASs exposure greater than
approximately two thousandth (0.002) of a drop [of water] in the average
yearly water intake of an American adult could be considered potentially
unsafe"

EPA limits (which are usually the federal action limit, not a recommended
consumption limit): [https://www.cdc.gov/nutrition/data-statistics/plain-
water-th...](https://www.cdc.gov/nutrition/data-statistics/plain-water-the-
healthier-choice.html)

------
iso1337
PFOA/PFAs are also widely used as DWR (Durable Water Repellant) for clothing.

Even Patagonia still uses chemicals in this class (or did as of 2015):
[https://www.patagonia.com/blog/2015/03/our-dwr-
problem/](https://www.patagonia.com/blog/2015/03/our-dwr-problem/)

More reading here: [https://www.motherjones.com/environment/2016/02/ski-
clothing...](https://www.motherjones.com/environment/2016/02/ski-clothing-
waterproof-pfoa-pfcs-perfluourochemicals-health-risks/)

------
contingencies
Ceramic nonstick cookware. Heavier, but does the same job.
[https://chemistry.stackexchange.com/questions/61420/what-
is-...](https://chemistry.stackexchange.com/questions/61420/what-is-the-
chemical-structure-of-ceramic-nonstick-coating-on-pans#69334)

------
zazen
There's better coverage of the lawsuit here:
[https://www.bloomberg.com/news/articles/2018-11-29/3m-dupont...](https://www.bloomberg.com/news/articles/2018-11-29/3m-dupont-
tussle-over-mega-lawsuit-on-cancer-linked-chemicals)

------
kristofferR
Wow, what an interesting coincidence:
[https://i.imgur.com/IPqwYGQ.jpg](https://i.imgur.com/IPqwYGQ.jpg)

I was just reading about fluorides in ski wax, and all the problems associated
with it and the upcoming EU ban, then I browsed HN and found this story on
top.

------
jabl
For a (much!) longer read about this stuff, the intercept has a 21-part series
here: [https://theintercept.com/series/the-teflon-
toxin/](https://theintercept.com/series/the-teflon-toxin/)

------
bartread
I find I have very little patience for breathless articles that include
acronyms in their headline and fail to clearly define those acronyms within
the first paragraph. This article therefore lands hard in the waste bin.

However, if you're interested, PFA stands for perfluoroalkoxy polymer.
Wikipedia has information here:
[https://en.wikipedia.org/wiki/Perfluoroalkoxy_alkane](https://en.wikipedia.org/wiki/Perfluoroalkoxy_alkane)

~~~
freehunter
This is a much better Wikipedia article on the subject, one that actually
explains why it's so dangerous:
[https://en.wikipedia.org/wiki/Perfluorooctanesulfonic_acid](https://en.wikipedia.org/wiki/Perfluorooctanesulfonic_acid)

There are major swaths of the country where PFAS and PFOS doesn't need to be
defined: it's common knowledge and the terms see daily use among the general
population as they drink filtered water to avoid ingesting it. But spelling
out the name doesn't tell you the story, so if you're discounting the
information because the name isn't spelled out, you're missing a major
disaster slow-rolling the industrial Midwest right now. The long form of the
name is the least interesting part of the article.

------
bigmit37
Any books I can read on non-toxic living? These days I feel like they are a
lot of toxic substances in our everyday products that should be substituted
for cleaner versions but I am not aware of all of them. Is there a useful book
on this subject?

Last year I read about pm2.5 in our air and have gotten some sensors and air
purifier to combat this particular problem.

------
nate_meurer
A major source of PFAS contamination is military bases. There are hundreds of
U.S. Air Force and Navy installations with fire and crash training sites,
where they literally dump thousands of gallons of PFAS-laden fire fighting
foam on the ground during exercises. A combination of brain-dead military
leadership and intensive lobbying by DuPont, Chemours, and others. The
Intercept has done some excellent reporting on this issue:

[https://theintercept.com/2018/02/10/firefighting-foam-
afff-p...](https://theintercept.com/2018/02/10/firefighting-foam-afff-pfos-
pfoa-epa/)

------
arobuck
Hi all,

Quick note: the headline is from a Massive Lab Note
([https://massivesci.com/notes/scientists-just-cut-the-
tolerab...](https://massivesci.com/notes/scientists-just-cut-the-tolerable-
intake-of-pfas-by-99-9/)), while the link above is pulling from an Oct 2018
article related to an ongoing US health study about safe limits of several
PFASs.

I skimmed comments below briefly--PFASs are used as processing components to
create non-stick cookware. They can be emitted directly from the cookware as
Teflon breaks down, becomes scratched, or is overheated. The "legacy" PFASs
have been largely phased out, with replacements like GenX taking their place.
These replacements offer similar toxicological consequences compared to
"original" PFASs.

------
mrfusion
Do you think it helps to buy spring water for drinking? Our tap water just
came out to have near the epa limit of pfas. (And the water company made it
sound like a positive thing!)

~~~
dbcurtis
We bought a counter-top distiller 15+ years ago and are never going back. If
fact, I think we have worn out 3 now. Highly recommend.

~~~
mrfusion
Can you link to it? I guess a distiller gets all chemicals out.

~~~
chihuahua
It seems that a distiller would remove those chemicals whose boiling point is
above the boiling point of water.

~~~
tryptophan
Low boiling point compounds, like say benzene, would just evaporate and then
condense with your water into your final product. Distillers get rid of heavy
things that don't boil, like metals and large contaminants like bacteria and
their waste products.

A carbon filter would get rid of the organics and low-boiling point things.

So optimal water purification would first use a carbon filter, and then
distill the output of that. Make sure to add minerals to the final product
though. Pure water is a vicious solvent and will slowly melt your teeth away.
It will also become quite acidic after sucking CO2 out of the air, so consider
adding some pH balancing salts too.

~~~
dbcurtis
The distiller I use has carbon filter packs at the output of the distillation
chiller (at the top of each carafe where the water enters).

------
newnewpdro
I recently saw a local notice about PFAs and their voluminous use in
firefighting foams at the nearby military bases and airports. Apparently it
was making its way into the drinking water.

The wikipedia page has some information.

[https://en.wikipedia.org/wiki/Firefighting_foam#Environmenta...](https://en.wikipedia.org/wiki/Firefighting_foam#Environmental_and_health_concerns)

~~~
jabl
See also

[https://theintercept.com/2015/12/16/toxic-firefighting-
foam-...](https://theintercept.com/2015/12/16/toxic-firefighting-foam-has-
contaminated-u-s-drinking-water-with-pfcs/)

[https://theintercept.com/2018/02/10/firefighting-foam-
afff-p...](https://theintercept.com/2018/02/10/firefighting-foam-afff-pfos-
pfoa-epa/)

Part of a 21-part series at [https://theintercept.com/series/the-teflon-
toxin/](https://theintercept.com/series/the-teflon-toxin/)

------
hedora
PFAs = PFCs. Not sure why they renamed them.

Maybe because PFCs have such a terrible reputation?

~~~
mimixco
Also called PTFE, Teflon, and GenX. You can never get rid of the molecule (so
they've found) but I guess you can try to get rid of the name?

~~~
icegreentea2
You're describing different things. Teflon is a brand name of PTFE, which is a
finished polymer. PTFE is considered safe until it has been subject to heat
stress and undergoes thermal breakdown (around 200C). This makes use of PTFE
as non-stick coating in cookware potentially dangerous.

GenX and PFOA are notionally different chemicals used in the manufacturing of
PFTE. They are both used to accelerate the polymerization reaction. It is
nominally possible to have finished PTFE products which do not contain
relevant (choose your definition) amounts of either family of chemicals. GenX
and PFOA are both toxic in themselves, regardless of use - unlike teflon.

~~~
mimixco
Yes, they're all different molecules but have the same essential
characteristics which make them dangerous: namely, that they all cause cancers
and birth defects and that they all pollute the water supply in a way that
cannot be remediated.

------
mimixco
Another story about Teflon! Why do these articles always bury the lede? Just
say it's Telfon!

There's a great documentary about this that came out last year called, _The
Devil We Know._ The TL;DR is that Dupont (seller of Teflon) and 3M (the
inventor) knew early on that Telfon caused birth defects and cancer.

They knew it would poison the water supply and could never be remediated. And
they went ahead and sold it, again and again, into thousands of products
because Dupont was earning about $1B in profits (on their $23B in revenue)
just from Teflon alone.

~~~
kurthr
Because teflon is not by definition a PFA (PerfluoroAlkoxyAlkane). It is C2F4,
while PFAs are C2F3O?? (where there is an oxygen cooridinated reactive fluoro
group dangling off at the ??)

Teflon is non-reactive and does not have these health issues. However PFAs can
be byproducts of the manufacture of teflon, and they can be used in similar
ways to teflon (they allow high temperature molding of corrosion resistant
materials). The primary contamination issue is with this byproduct,
particularly when it was manufactured, sold and used as a fire suppressing
foam.

The people who dumped that crap and covered it up deserve jail time, but
uninformed fear mongering doesn't serve the public either.

~~~
mimixco
This is not correct. Please watch the documentary film. Teflon absolutely has
these health issues. You can move the tail ends of the molecule around all you
want to and it still has the same dangers.

~~~
kurthr
Ummm... tail? C2F4 doesn't have one. It will form a polymer, but it doesn't
have a tail. As I mentioned sulfates may be a byproduct in some manufacturing
(precipitation) processes, but not in cookware where their contamination would
be absolutely critical at ppm levels.

Perhaps you mean the coordinating Oxygen in PFA or the Sulfur in PFOA, PFOS
(ScotchGuard)? Those chemicals are known to be toxic and contaminated many
marine animals and watersheds... some are regulated, some are not, and some
companies have ignored the regulation, or the regulators have ignored the
pollution. It's bad, but not relevant to teflon PTFE per se.

~~~
mimixco
It seems like you might not have seen the film. I'm not a chemistry expert,
but it was quite enlightening. Maybe if you get a chance to watch it you cost
post your thoughts...

------
doctorpangloss
Chemical companies are pretty much never the protagonists. Stories about green
revolutions feeding lots of people or whatever are good tries at making the
chemical company the good guy. But there will always be something impeachable
about whatever it is that DuPont and 3M do.

It sort of doesn't matter what the specifics of the toxicity are, which people
will litigate here endlessly. So for once, consider that talking about the
specifics of the toxicity is, fundamentally, co-opted by the antagonists of
this scenario, because it sows confusion. Making it a science problem is
attractive, but that line of problem solving is certainly perceived by the
public to have long been hijacked by moneyed interests.

Because if PFAs really caused cancer, or vaccines really caused autism, or
pornography really caused massive amounts of violence against women or
whatever--if it was really a hair on fire problem, we'd know. Air pollution
really causes lung cancer, and it's seemingly invisible, but the hair on fire
problem _does_ exist there: visit Delhi. There, it's visible.

In the United States, a lot of low hanging fruit has been addressed. So the
kind of faucets-on-fire urgency that we saw with fracking is actually very
rare nowadays. Yet we have a legacy environmental movement oriented too
strongly around finding issues like that, that are capable of communicating
only about issues like that. Ecoterrorism, class action lawsuits, big urban
protests, reactionary political campaigns--it's great for getting rid of air
pollution and visible disasters like that, but it's ineffective for stuff
that's just a bunch of boring science.

We'll eventually figure out how to litigate environmental problems. It won't
at all resemble this preposterous adversarial trial and torts system.
Goodnight to environmental lawyers, on both sides, despite their intentions.
To keep this on topic for this forum, the person who figures out how to save
the environment will definitely _not_ be some grad student or $500k/year 50
y.o. industry MEng trying to make patentable inventions to get funded by VCs.
People chasing the dollars _are_ the environmental problem, after all.

The people caught up in details of economics, law and scientific toxicity will
just go away (i.e. technocrats) from this problem. We kind of already know
that DuPont and 3M are guilty parties in something here. It won't be important
to normal people what precisely corporate polluters are guilty of, because a
normal person will _never_ be on the wrong side of that justice equation.

~~~
pathseeker
>because a normal person will never be on the wrong side of that justice
equation.

If someone uses a hammer to kill their spouse, the hammer manufacturer
definitely is not on the wrong side of the justice equation and the person is.

~~~
doctorpangloss
The torts system is almost certainly co-opting the criminal justice system,
not the other way around.

It's precisely because of some law needing to be fair to hammer manufacturers,
who literally no one cares about, that gun manufacturers, which pretty much
everyone does care about, can do shitty things in this country. You're
thinking in terms of law, and I'm talking about a court of public opinion.

And even if you litter (pretty much the worst a normal person can do in the
court of public opinion re: pollution), we don't need years to litigate that
in a court of law.

And yet, it took five years to litigate the BP Horizon spill, even though
there's camera footage showing oil coming out of their derrick in real time.
What was there to litigate there? Who really cares whether it's $18.7 billion,
or $187 billion, or $1.8 billion, other than the BP chairman? Who really cares
what they think, in the court of public opinion?

No normal person is ever going to have $18.7 billion to lose, nor will ever
have the capability of doing the kind of environmental damage BP's bad oil
platform did. So why allow environmental law to even adjudicate the matter,
over years, which has never _once_ , ever, delivered maximum justice to the
public?

Why compromise on our values and the environment, constantly, to protect some
essentially unproven economic logic that BP, or DuPoint, or whoever, generate
more value for some community somewhere in "jobs" or whatever than the damage
they did by polluting?

The primary normative question in that case: Should we just shut down BP? We
didn't need 5 years of negotiations to resolve that, we didn't need any more
evidence or calculations. Someone in the justice department, in an afternoon,
made the determination that BP won't be closed, and then a complex legal
strategy was pursued, by both sides, for five years, to generate the illusion
of justice to execute on that determination.

Pollution cases _act_ like criminal cases, and they _shouldn 't_ be! The whole
problem is reductive, slow, storied, legalistic reasoning, and reductive,
unproven economic aphorisms.

~~~
pjc50
> Should we just shut down BP?

By what legal process? What happens to the assets, the investors and staff?
Does it matter that the British Petroleum is, in fact, a British company?

