
Perchlorate, used in rocket fuels, may be more hazardous than previously thought - headalgorithm
https://www.hopkinsmedicine.org/news/newsroom/news-releases/research-story-tip-something-in-the-water-environmental-pollutant-may-be-more-hazardous-than-previously-thought
======
aasarava
I covered a Texas Tech study that showed how perchlorate can be passed to
babies via breast milk. That was in... 2005. The EPA's recent decision is
extremely disappointing. [https://www.wired.com/2005/02/rocket-fuel-fed-to-
newborns/](https://www.wired.com/2005/02/rocket-fuel-fed-to-newborns/)

(An aside: Reporters don't usually choose their own headlines. I fought and
lost a battle with my editor on that one.)

~~~
morninglight
Riverside California also performed tests showing high levels of perchlorate
in the drinking water at about the same time. The test results have not slowed
residential growth in Riverside.

I'd love to see test results from Lompoc. Actually, anyone living within 10
miles of a military base needs to pay attention to their water quality.

------
Metacelsus
It's also a big component of fireworks – and every July 4th levels in lakes
and rivers spike.

That being said, this paper only presents in vitro data. Perchlorate may be
more toxic than assumed, but the evidence isn't strong.

[https://sci-hub.tw/10.1038/s41594-020-0417-5](https://sci-
hub.tw/10.1038/s41594-020-0417-5)

~~~
alexandercrohde
>> but the evidence isn't strong.

I always feel compelled to point out that absence of evidence isn't evidence
of absence. Or chemicals should be presumed unsafe until proven safe, rather
than the other way around.

~~~
nickff
The problem with precautionary principle arguments (like your latter point) is
that the precautionary principle is not self-consistent. You'd need to know
the effect of implementing the precautionary principle before using it, which
is probably impossible to calculate.

~~~
jackyinger
The precautionary principle is the initial condition though! (Ideally
speaking, of course.)

The idea is to assume new chemicals may be dangerous. Then undertake careful
testing programs to determine if they really are dangerous. I think that this
is what the grandparent comment was suggesting.

There is good precedent for the use of this principle, take for instance drug
trials. Furthermore, I think it would be beneficial to assume all new
technologies may have detrimental effects, and weigh those effects carefully.

~~~
nickff
The precautionary principle could only be the initial condition if it had been
followed since the beginning of time; you want it to be _our initial
presumption_ , a presumption whose sole virtue is its convenience for PP
advocates.

------
annoyingnoob
There is an area outside of Gilroy where a safety flare manufacturer had been
dumping perchlorate in a pond for years. It was showing up in local wells
years later and bottled water was provided for years until the levels went
down enough. Now maybe it wasn't enough? Ouch.

------
clumsysmurf
> In May 2020, the U.S. Environmental Protection Agency (EPA) ruled not to
> place regulations on the amount of perchlorate that can be allowed in
> drinking water.

Predictable. Just 150 days left to vote.

~~~
ianlevesque
I don’t get it. Do these people not live in the same country as everyone else?
Breathe the same air and drink water? It’s madness.

~~~
rayiner
The EPA declined to regulate perchlorate because, among other things, it’s not
found in very many water systems and is naturally occurring in the southwest.
(When the EPA tested thousands of systems in 2011, under the Obama
administration, just 0.62% had perchlorate levels about the EPA recommended
limit:
[https://www.federalregister.gov/documents/2011/02/11/2011-26...](https://www.federalregister.gov/documents/2011/02/11/2011-2603/drinking-
water-regulatory-determination-on-perchlorate.))

Instead, EPA has been pursing less formal measures to reduce perchlorate in
the specific drinking water systems where it has been found:
[https://www.epa.gov/newsreleases/epa-notes-successes-
reducin...](https://www.epa.gov/newsreleases/epa-notes-successes-reducing-
perchlorate-drinking-water)

As one of “those people” who thinks it’s harmful to have a national regulation
where a more local one will do, I don’t see the problem with this. There are
many kinds of pollution that are national in nature, but drinking water is
actually fairly localized. There is no evidence perchlorate pollution migrates
great distances, so why do we need an nationwide regulation?

It should be noted that drinking water systems are almost entirely run by
public entities, and already face massive funding challenges. When the EPA
sets maximum allowable levels of a pollutant, it triggers a huge bureaucratic
framework that everyone must follow. Is it unreasonable to decide that we
don’t need to force everyone to go that far for a chemical that appears in
possibly concerning levels in less than 1% of systems?

This is an excellent example of how even the slightest push back on the notion
that the federal government should regulate anything and everything is treated
by the media as a crisis of epic proportions. You didn’t know what perchlorate
was before this article, and it doesn’t affect 99% of water systems out there,
but the EPA declining to create nationwide monitoring and enforcement
framework for the chemical is somehow “madness.”

~~~
kjaftaedi
I can only assume you live near an estuary.

Do you really believe that water pollution is only a problem to be handled by
people who are downstream and not a shared responsibility?

~~~
rayiner
I live on the Chesapeake Bay, the country’s largest estuary. (I’m staring out
my window at the water right now.) Of course I believe that water pollution is
a shared responsibility—much of the silt in the Bay comes from agricultural
operations in New Jersey and Pennsylvania. But the EPA continues to push along
NY/NJ/PA into meeting their 2025 TMDL targets for run-off into the Bay.
Phosphorus and nitrogen from agricultural activities is the archetypal example
of something that must be regulated at the federal level, and Wheeler doesn’t
deny it. (There is an ongoing spat about whether the TMDLs are directly
enforceable against the states, but the EPA’s current position was formulated
during the Obama administration.)

But what doesn’t come floating down the river is perchlorate. Accepting that
the EPA must regulate certain types of water pollution doesn’t mean that all
water pollution must be regulated at the federal level.

------
eqvinox
Aw man... perchlorates are also pretty abundant in Martian soil... another
hurdle for future terraforming I guess :/

(Last I checked, [some] plants weren't bothered too much by these, but the
question then is whether they accumulate in fruit...)

~~~
teruakohatu
This may be a stupid question, but can anything be planted in Martian soil,
even if the atmosphere was corrected? I always assumed not.

~~~
AnotherGoodName
On the atmosphere point that's one thing that isn't as much of a problem.
Plants can breath in Mars atmosphere and pressure.

Sure the pressure is 0.6% comparing Mars/Earth but the CO2% is 0.04% when
comparing Earth/Mars.

In other words the partial pressure of CO2 on Mars is actually higher than on
Earth. Which is great for CO2 breathing plants. If the temperature was raised
a plant would have more CO2 available even with the much lower pressure than
on Earth.

Indeed experiments with 95% CO2 (matching Mars) and 6millibars pressure
(matching Mars) and with martian soil showed that Potato's grow fine.
[https://cipotato.org/blog/indicators-show-potatoes-can-
grow-...](https://cipotato.org/blog/indicators-show-potatoes-can-grow-mars/)

The only adjustment was temperature!

~~~
wollstonecraft
But how is this possible? Water has a vapor pressure of 23 millibars at 20 C,
meaning water would boil from the leaves.

~~~
AnotherGoodName
It boils but it takes many hours to boil off completely. Here's a study of the
time taken to evaporate water in a near vacuum at 20C:
[https://www.hou.usra.edu/meetings/lpsc2014/pdf/2060.pdf](https://www.hou.usra.edu/meetings/lpsc2014/pdf/2060.pdf)

25ml of liquid water takes 3 hours to completely boil off under vacuum. Less
if the water is mixed in with other substances (eg. soil). The inner structure
of the plant itself is capable of trapping water to an even greater extent. To
the point where water directly boiling off the plant directly isn't
significant.

Note that this was simulating asteroid conditions. Mars is slightly better at
retaining water since it has slightly more pressure. This is why it's pretty
likely that we're seeing flowing water on Mars each summer:
[https://www.nasa.gov/press-release/nasa-confirms-evidence-
th...](https://www.nasa.gov/press-release/nasa-confirms-evidence-that-liquid-
water-flows-on-today-s-mars)

------
JoeAltmaier
Until 10 years ago, Dry Cleaners used this for all our clothes.

~~~
steffan
You’re thinking of Tetrachloroethylene (perchloroethylene)

~~~
JoeAltmaier
Am I? Is that different?

~~~
cbkeller
Both contain Cl but perchlorate is a highly oxidizing anion (ClO4-), while
perchloroethylene is relatively unreactive (though carcinogenic) organic
compound (Cl2C=CCl2)

------
mannykannot
Perchorate is one of those chemicals that I first heard of on account of their
use as rocket fuels. It seems that you won't go far wrong by regarding
anything in that class as hazardous.

------
jabl
Space rockets should all switch to hydrolox, at least that burns clean. Like
Delta IV.

(yeah, yeah, terrible impulse density..)

~~~
cryptonector
What's wrong with methane/oxygen?

~~~
jabl
\- methane is a very potent greenhouse gas. What's the effect of methane in
the stratosphere?

\- there are some results suggesting soot emissions in the stratosphere could
be a problem if space launches increase a lot. Methane burns a lot cleaner
than kerosene, but afaiu some soot is still formed.

Now all things considered, given nobody seems interested in a pure hydrolox
lower stage due to the poor impulse density, methalox certainly looks better
than alternatives.

~~~
chris_va
GHG emissions from rocketry are so trivially small that it's really not worth
optimizing at this point. Maybe if SpaceX flew 500 rockets per day.

(disclaimer: I work in a climate research group)

~~~
jabl
Total volume is trivial compared to all other human activity, but like I
mentioned there is some concern about the effect of rocket emissions in the
middle and upper atmosphere given that we're likely to see a substantial
increase in launch rate. See [https://eos.org/features/the-coming-surge-of-
rocket-emission...](https://eos.org/features/the-coming-surge-of-rocket-
emissions) for a recent overview.

