Perchlorate, used in rocket fuels, may be more hazardous than previously thought
hopkinsmedicine.org
hopkinsmedicine.org
(An aside: Reporters don't usually choose their own headlines. I fought and lost a battle with my editor on that one.)
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.
That being said, this paper only presents in vitro data. Perchlorate may be more toxic than assumed, 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.
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.
Is "let's wait and see" a precautionary move?
Are you saying the cost of inaction must be quantified before it's a legitimate choice?
In which case, in our world of imperfect understanding, does that lead to bias towards action?
Predictable. Just 150 days left to vote.
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...
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.”
The EPA isn’t leaving it to local governments whether to test or to decide what the levels should be. They’re concluding that, based on testing they already did, there is no need to require formal monitoring of perchlorate in every water system just because a tiny minority of systems have concerning levels of the chemical. And it’s handling those exceptions on a case-by-case basis.
https://thehill.com/policy/energy-environment/489753-epa-sus...
Some things don't need to be checked. Some reporting can be postponed.
You don't get to dump truckloads of barium perchlorate into the Hetch Hetchy reservoir.
https://www.scientificamerican.com/article/trump-rsquo-s-epa...
IANAL and don't have skin in this game. I did, however, volunteer at a treehugger org for a decade. The mission was to protect wetlands for fish, birds, flood control, pollution. I got hear plenty from the org's scientists and lawyers about the merits of self-policing.
And maybe that's fine! But the supposition that the EPA setting a standard relevant to tens of thousands of municipal water districts will generate zero costs for those municipalities glosses over how the bureaucratic wheels turn.
Do you really believe that water pollution is only a problem to be handled by people who are downstream and not a shared responsibility?
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.
That's not what he said. He said perchlorate pollution in water does not necessitate national regulation given the data. That says nothing about other chemicals which may disperse more widely or whose use is so common as to contaminate many water systems.
> All in all, “we have an incredibly safe and reliable water supply” in the United States, said David Jones, professor of history of medicine at Harvard Medical School.
The article you linked appears to be about comparing treated water to "raw water", which seems rather tangential to our discussion of considering the quality of treated water.
I'm just saying, a lot of people have implicit trust in their water without even knowing what's in it or why 0.62% of americans with perchlorate are somehow clumped in with the americans who are lucky to not have it in their water—surely this would be a success because only 0.62% of water needed extra infrastructure investment and regulation?
After all, perchlorate is unlikely to remain at such a low penetration with continued use....
https://en.wikipedia.org/wiki/Stand-your-ground_law#United_S...
They know this stuff is bad but they are confident their wealthy town or county will not allow it to impact the drinking water supply. It'll be "someone else most likely poorer areas" problem.
> Many in the media have parroted the absurd claim that the water crisis was caused by austerity, as if the government cared more about saving pennies than saving lives. The truth is exactly the opposite: Keeping DWSD as Flint's water provider was a cheaper option, but one that would have created zero new infrastructure jobs
Btw, it’s absolutely unacceptable to justify the degradation of water quality with jobs. Regardless the reasoning it was entirely irresponsible given the infrastructure in the area.
Anyway it’s not like there’s any shortage of examples that austerity leads to loss of life.
Also ran: Chrome-6 https://www.ewg.org/release/ewg-brockovich-carcinogen-found-...
Cheers!
that is the strangest re-telling of the Flint water-quality story that i've ever heard.
Nearly everything indicates that the steps in Flint were cost-saving measures that the citizens either 1) didn't know about, 2) were told that there wouldn't be problems, and 3) were promised health concerns wouldn't be a factor.
Where exactly does this 'wealthy town that's overly confident" narrative fit? That hasn't been my perception at all with Flint.
Even as detailed by the left-leaning NPR: https://www.npr.org/sections/thetwo-way/2016/04/20/465545378...
So, no. They don't really live in the same environment as everyone else. Why would they care about its destruction?
"Freedom" is more important, apparently. /s
For (absurd) example, does this ruling mean that I could give a child a glass of "water" that's 50% perchlorate, and because of EPA's ruling I'm legally untouchable?
(Last I checked, [some] plants weren't bothered too much by these, but the question then is whether they accumulate in fruit...)
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-...
The only adjustment was temperature!
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...
You'd have to fertilize the soil of course, but fundamentally plants don't need that much to grow. A lot of hydroponics use a completely inert "gravel" like substance and just wash a nutrient solution through on occasion.
It might not all be in amounts easily scavenged, but they're mostly there.
[0]: https://www.nasa.gov/feature/can-plants-grow-with-mars-soil
(yeah, yeah, terrible impulse density..)
- 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.
(disclaimer: I work in a climate research group)
The downside would be the massive instability from the need to keep a supersonic flow matched up perfectly with the detonation velocity. I'd figure stochiometric deviation would be a feasible way to control the detonation velocity, but the control loop would be hard to get right. And it might be necessary to use film cooling with liquid cryogenics to prevent the shock front from melting the engine wall.