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Toxic fluorinated compounds found in drinking water of 33 states

news.harvard.edu

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Re: Toxic fluorinated compounds found in drinking water of 33 states

#51

Post by herbps10 »

lawpoop wrote: post #14
herbps10 wrote: post #7

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.

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?

The best way to prevent this, in my opinion, is to be clear that the research has nothing to do with fluoridated water.

From my colleague: "The highly fluorinated chemicals that we discussed are organic compounds, meaning that they contain carbon atoms. They are called highly fluorinated or per- and polyfluoro alkyl substances because they have many fluorine atoms, and the carbon atoms are entirely or often bound to fluorine (There may be highly fluorinated chemicals that aren't strictly PFASs, but that's a minor point). These highly fluorinated chemicals have unique chemical properties that give them their characteristic grease and water resistance (typically one end of the molecule is more soluble in oil, and the other end is more soluble in water, similar to other surfactants). The concerns about PFAS toxicity stem from the properties of the whole molecule and not just because they contain fluorine."

Re: Toxic fluorinated compounds found in drinking water of 33 states

#52

Post by djsumdog »

throwaway91111 wrote: post #32
hughes wrote: post #3

Earlier quoted context omitted.

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

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

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.

Re: Toxic fluorinated compounds found in drinking water of 33 states

#54

Post by Diederich »

throwaway91111 wrote: post #32
hughes wrote: post #3

Earlier quoted context omitted.

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

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

You said 'seems', which seems to leave the topic open to discussion in your mind. (:

What's the downside to adding appropriate amounts of fluoride to municipal water sources?

EDIT: after I posted this, I did some quick Googling, and man this is an all over the map topic. There APPEARS to be reasonable evidence on both sides of the debate, but honestly, I'm not personally vested in this enough to dig any more.

Re: Toxic fluorinated compounds found in drinking water of 33 states

#55

Post by daveguy »

sndean wrote: post #10
refurb wrote: post #6

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...

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,…

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.

Re: Toxic fluorinated compounds found in drinking water of 33 states

#56

Post by philipkglass »

gtrubetskoy wrote: post #46
philipkglass wrote: post #18

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…

> This article is about heavily fluorinated organic compounds -- molecules with a carbon skeleton and all or most of the hydrogen atoms replaced by fluorine. such as Teflon?

Yes, though Teflon itself is of such high molecular weight that it's not a hazard that way. Some chemical intermediates and additives associated with Teflon manufacturing and/or application are hazardous though, like perfluorooctanoic acid:

https://en.wikipedia.org/wiki/Perfluorooctanoic_acid

Re: Toxic fluorinated compounds found in drinking water of 33 states

#57

Post by Nition »

throwaway91111 wrote: post #32
hughes wrote: post #3

Earlier quoted context omitted.

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

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

Floride in water is really meant for the people who aren't going to use mouthwash, or floss, or brush their teeth as much as they should anyway. It brings up the dental health of the group with the worst dental health.

Re: Toxic fluorinated compounds found in drinking water of 33 states

#58

Post by general_ai »

diogenescynic wrote: post #48
general_ai wrote: post #26

Earlier quoted context omitted.

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.

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'Rou…

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".

Re: Toxic fluorinated compounds found in drinking water of 33 states

#59

Post by [deleted] »

08-15 wrote: post #42
philipkglass wrote: post #18

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…

> Why are these compounds hazardous? > - Harmful biological effects in the human body, like hormone-mimic activity. Can you provide some evidence for that claim? I know that perfluoro compounds degrade very slowly and accumulate in fatty tissue, but I haven't seen a supported claim about harmful effects. From the misleading links in the article, I suspect more than a few people confuse PFAS and PCBs.

[deleted]

Re: Toxic fluorinated compounds found in drinking water of 33 states

#60

Post by Dangeranger »

general_ai wrote: post #26
the_gastropod wrote: post #8

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

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.

Let me make sure I understand your argument; The EPA was not able to prevent a State's local budgetary decisions regarding drinking water. Therefore it would be more effective if we cut funding to the EPA?
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