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Unsafe Lead Levels in Tap Water Not Limited to Flint

nytimes.com

81–90 of 146 posts

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#81
post #62

Earlier quoted context omitted.

Carbon filtration will not remove dissolved solids (lead, heavy metals) without added ion-exchange resins. RO is generally the most effective broad spectrum treatment method for drinking water. The mineral issue is pretty much bunk, if the lack of trace minerals in your water is a concern you need to see a doctor. Food is your body's preferred source of minerals, you have to drink a lot to have much effect on your da…

I'm a water treatment engineer. Carbon filtration will remove dissolved solids and heavy metals, and with high efficiency if done correctly. Most GAC columns designed to remove lead and heavy metals are enriched with sulfide ions to increase the removal efficiency as well. People prefer to use ion exchange resins to remove heavy metals because they can be regenerated more easily and efficiently. Also ion exchange res…

What home products would you recommend, either flow-through pitcher style or faucet or whole-house?

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#82
post #3

Earlier quoted context omitted.

> Ancient Romans knew that lead water pipes were unhealthy and so they preferred terracotta pipes. Do you have a source for this? At the same time, they used lead acetate to sweeten wine and food, which is way more dangerous. If they made the weaker connection between health and water pipes, they should have been able to connect health and this as well.

Read Vitrivius's De Architectura, specifically the part on building aqueducts. It's basically a manual for "So the Emperor told you to build a city from scratch…" As a random aside, he also includes a proof that the water level mechanism he prefers works even though the Earth is a (roughly) spherical object and not a flat plane.

Couldn't find it in the book itself, but it is referenced here. https://en.wikipedia.org/wiki/De_architectura#Materials

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#83

Earlier quoted context omitted.

This is a rather ridiculous myth, in the same tradition as moon-landing denial or Korean fan death. You get minerals from food, not water. You (presumably) have kidneys and other organs that maintain the mineral balance in your body. A few micrograms more or less in your water isn't going to make much difference.

I hardly think it's a myth. Human bodies aren't as simple as you're suggesting. It's a complex process but no water found in the natural world is going to be pure H2O so it makes since to be cautious of water that is going to be so different from nature. From the WHO report[1] on water quality: "Sufficient evidence is now available to confirm the health consequences from drinking water deficient in calcium or magnesi…

[deleted]

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#84
post #4

Nassim Taleb taught me that the absence of known danger is not the same as safety. Repeat that to yourself the next time you read your cities water report. It's not "I know my water is safe" it's "I know I don't face these specific dangers. What else could be in the water that they don't test for?" Look into reverse osmosis.

> the absence of known danger is not the same as safety.

Feynman had some interesting comments on this problem regarding NASA's "it worked ok last time" approach to risk assessment before the Challenger Disaster.

https://www.youtube.com/watch?v=4kpDg7MjHps#t=150

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#85
post #78
post #2

Ancient Romans knew that lead water pipes were unhealthy and so they preferred terracotta pipes. It's hard to imagine why the U.S. ever had a single lead water pipe, let alone huge numbers of them. Updated with a reference for the downvoters: Sheets of lead were used to line Roman aqueducts (as was cement) and lead pipes to convey water. But lead also was known to be unwholesome and, for that reason, pipes made of cl…

>It's hard to imagine why the U.S. ever had a single lead water pipe, let alone huge numbers of them. I always supposed that that's where the word 'plumber' came from, or 'loodgieter' (lead caster, Dutch). Both words strongly refer to lead. Growing up in Holland in the early 80's our house had lead pipes. When I bought my first house in 2003 it too still had a lead water main. I drank a lot of that water, tap water o…

Just noticed that in french lead is "plomb" and plumber is "plombier"

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#86
post #2

Ancient Romans knew that lead water pipes were unhealthy and so they preferred terracotta pipes. It's hard to imagine why the U.S. ever had a single lead water pipe, let alone huge numbers of them. Updated with a reference for the downvoters: Sheets of lead were used to line Roman aqueducts (as was cement) and lead pipes to convey water. But lead also was known to be unwholesome and, for that reason, pipes made of cl…

> It's hard to imagine why the U.S. ever had a single lead water pipe, let alone huge numbers of them.

Lead has some advantages. Its melting point is low, so it's easy to weld. It doesn't corrode quickly, so pipes last a long time. And it's malleable, so pipes don't break when soil and foundation shift. But yes, it's very poisonous, so the advantages are moot for drinking water.

For corrosive waste plumbing, on the other hand, it can be a good choice. It even tolerates HF, which glass doesn't. Glass is sexier, however.

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#87

Earlier quoted context omitted.

This is a rather ridiculous myth, in the same tradition as moon-landing denial or Korean fan death. You get minerals from food, not water. You (presumably) have kidneys and other organs that maintain the mineral balance in your body. A few micrograms more or less in your water isn't going to make much difference.

I hardly think it's a myth. Human bodies aren't as simple as you're suggesting. It's a complex process but no water found in the natural world is going to be pure H2O so it makes since to be cautious of water that is going to be so different from nature. From the WHO report[1] on water quality: "Sufficient evidence is now available to confirm the health consequences from drinking water deficient in calcium or magnesi…

There are two completely-unrelated assertions in that paragraph. I believe one of them -- that dietary Ca and Mg are important -- but not the part about water being an important source of either. The numbers simply make no sense.

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#88
post #21

Earlier quoted context omitted.

You will notice the taste difference though.

And for an extremely cool experience, try black water: http://getblk.com/ For varying definitions of extremely

Sounds like swamp water ;)

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#89
post #46

If I travel to the US (Let's say Los Angeles, Seattle and New York) how do I know if the tap water is safe to drink? In the EU I normally just ask a local. In Germany it's safe to drink but in the Czech Republic you might be better off drinking bottled water (last time I checked was ~10 years ago, sorry if it's changed).

Re. Czech Republic -- nothing has changed, in the sense that drinking tap water was perfectly safe ten years ago, as it is now. I suppose that demonstrates the dangers of your "ask some local" approach :) Though the safety of tap water in CZ is well known, and has been well known for decades, and any local would tell you as much. So I'm not sure where that came from. Perhaps some temporary local incident? Even Google…

Odd, I'll ask my father why he thought it wasn't a good idea. Thanks.

Re: Unsafe Lead Levels in Tap Water Not Limited to Flint

#90
post #62

Earlier quoted context omitted.

Carbon filtration will not remove dissolved solids (lead, heavy metals) without added ion-exchange resins. RO is generally the most effective broad spectrum treatment method for drinking water. The mineral issue is pretty much bunk, if the lack of trace minerals in your water is a concern you need to see a doctor. Food is your body's preferred source of minerals, you have to drink a lot to have much effect on your da…

I'm a water treatment engineer. Carbon filtration will remove dissolved solids and heavy metals, and with high efficiency if done correctly. Most GAC columns designed to remove lead and heavy metals are enriched with sulfide ions to increase the removal efficiency as well. People prefer to use ion exchange resins to remove heavy metals because they can be regenerated more easily and efficiently. Also ion exchange res…

Carbon filtration doesn't remove fluoride, does it? (Or arsenic) The only water filtration system I have found that removes fluoride is the Berkey brand. I've not seen any filtration systems in the stores even mentioning fluoride or arsenic.

Berkey filters http://bit.ly/1WdBneq (Edit to add arsenic and Berkey link)

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