They said an anti-corrosive agent wasn't added to the water but what is corrosive in the water other than water or is "plain" water the cuplrit? I
guess what I'm asking is that why if you typically add an anti-corrosion agent to water why wasn't it done?
[Edited on 21-1-2016 by Morgan]Praxichys - 21-1-2016 at 10:51
I live about 30 miles from Flint, and thankfully I have a well.
Road salt in Michigan is out of control. It is nearly impossible to get vehicles to last when they get hosed with brine for four months out of the
year. I would be ecstatic if we switched to sand.annaandherdad - 21-1-2016 at 12:56
Morgan thanks for the links. I followed some of them to get better answers to my questions, and found this one which helps:
After filtering the water per government directions, I would recommend a possibly additional step based on chemistry to further address dissolved
PbCl2 or other transition metals in their higher valence state. First, I would raise the pH of the water. I own and on occasion have used a machine
(MicroLite Jupiter Water Ionizer) that can make water more alkaline, generally for taste reasons. Next, aerate the water (fish tank air pump and
accessories) and wait for any sediment to settle.
Some chemistry, first the equilibrium of dissolved oxygen in an alkaline solution forming a superoxide anion and a powerful disinfecting hydroxyl
radical:
O2 + OH- = .O2- + .OH
Next, the property of the superoxide anion to lower the valence state to generally insoluble salts:
In spite of these added measures, the water may still be not safe to drink as more organically complexed Pb, for example, would not likely be made
insoluble. As such, I would never drink say water, and as bathing could permit the absorption of soluble toxic heavy metals through the skin, the
largest organ in the body, you may wish to rethink that as well. Drink bottled water only.
[Edited on 22-1-2016 by AJKOER]BromicAcid - 21-1-2016 at 16:38
Note that due to dissolved carbon dioxide even regular rain water has a pH of <7, some sites claim 4.5-5.5. While that is not impressively acidic,
it does give a decent zero point. From there combine that with dissolved oxygen and industrial pollution you have the beginnings of a corrosive
substance. Hardly corrosive in the standard way of thinking but enough apparently to strip a few PPM of lead.AJKOER - 21-1-2016 at 16:59
More like galvanic corrosion based on the increase presence of salt (an excellent electrolyte), an oxygen source (air), non-neutral water and one or
more metals. Fundamentally, elements of the dissolution are electrochemical in nature.Morgan - 22-1-2016 at 06:07
Here's another slant I recall hearing about.
"Fecal coliform bacteria appeared in the city’s water in the summer of 2014. Officials addressed the bacteria problem by pumping extra chlorine into
the system, but did not add any corrosion control treatment. The water, which had become highly corrosive, caused lead to start leaching from pipes
and home plumbing as it flowed through the city." http://www.nytimes.com/interactive/2016/01/15/us/flint-lead-...annaandherdad - 22-1-2016 at 08:57
I can't find a clear statement of what was wrong with the water from the river, but as near as I can reconstruct it, the river water had too much salt
(sodium chloride) in it. The articles I've seen seem to confuse "chloride" with "chlorine" , the latter used to kill microorganisms. One article by
the Virginia group talks about how the chlorine concentration went down as the pipes corroded. But surely Detroit water has chlorine in it, too.
I'd like to see a straightforward chemical analysis of the river water, like the kind they put on bottles of Italian water.
I wonder if any other community uses that river for its water supply. If the problem is sodium chloride, then maybe it comes from road salt, as
Praxichys mentions. You'd think that salt in water would be a common problem in many locations.
In any case, someone screwed up big time. Dr.Bob - 23-1-2016 at 16:55
I read one article that did say that the water contained more compounds that dissolved lead in the pipes, likely a mixture of phosphates, acids,
chlorine/chloride, and maybe ammonia, which can cause chloramine formation. All of those can help dissolves small amounts of lead. The numbers I
saw said that with Detroit water they had about 5 ppb of lead, but with the new water source it had gone up to 10-20 ppb. None of those numbers are
ideal, but none will cause acute problems. But any amount of lead is bad for children. The bigger issue is the number of pipes containing lead or
lead solder, plus many homes there have faucets made with brass that contains some lead as well.
So it is not that the Flint water is inherently toxic, it is simply more corrosive than the water that they had before, and their water system has
lead in it. I think it was a case of government bureaucrats being inept than any real conspiracy. It happens more often than most people realize,
but nowadays it often goes the other way. I have seen cases of a water system being considered contaminated it had 1 ppt of mercury (one person eats
a tuna fish salad sandwich and pees). That is just silly.
[Edited on 24-1-2016 by Dr.Bob]annaandherdad - 23-1-2016 at 17:40
Dr Bob, you mean ppb not ppm, don't you? I thought the EPA limit for lead in drinking water was 15ppb (parts per billion). The Virginia group
found some cases that were over 1000 ppb.
I think you're exactly right about inept bureaucrats.BromicAcid - 23-1-2016 at 22:02
According to the 2014 annual water quality report for Detroit (available online) the 90th percentile value for lead concentration was at 2.3 PPB,
action level was at 15 PPB (as annaandherdad mentioned above). Intergalactic_Captain - 24-1-2016 at 08:10
Dr. Bob touched on the lead source, but I think there's something a bit more disturbing underlying this. Sure, measurable amounts of lead can be
leached from brass, copper pipe soldered with traditional alloys, pure lead potted joints, etc... However, up until the introduction of pvc, cpvc,
and the more modern PEX (which on a tangential point, uses brass fittings), copper/brass and iron pipe were, and in most cases still are, the de-facto
existing distribution system in anything that isn't new construction.
So why don't we hear about situations like this more often? There are plenty of municipalities around the world, let alone the US, with aging
infrastructure. Hell, just where I live, at least three townships have seen major supply changes in the last few years. Should we all be running
tests to see if 50-200 years of passivation is being stripped from our pipes and served up at the faucet?
And that brings me to my main point. Every news story, article, or tidbit I've come across mentions "lead pipes" - Not just lead as in solder or
brass, mind you, but lead plumbing. I find this to be deeply unsettling - Yes, much of the infrastructure we rely on is generations old, buried, and
only even thought about when it breaks down. But really, it's 2016, and we have a major city in the USA brought to the national spotlight because
their lead pipes are poisoning them? To hell with the water supply, that in and of itself should be an embarassment and a wakeup call to literally
everyone with a pulse.neptunium - 24-1-2016 at 08:37
I live in Detroit and from what I heard they had an e.coli problem first. They solved it with chlorine but created another issue when too much was
added increasing the acidity and corroding the lead pipes.
I don't know who is in charge up there but more than a few lost their job.
As far as I can remember, I've always been told to run the water a few seconds before filling my glass to evacuate the first volume of water standing
in the pipes.
It is an embarrassment you're right!
[Edited on 24-1-2016 by neptunium]Morgan - 24-1-2016 at 09:41
My utility authority said to run the water 3 minutes if I recall in the morning to rid the water of lead. They were refering to older water meters
that can leach lead from the brass. It's always stuck with me that lead is poisonous in parts per billion.
It doesn't seem like fluoridation is helping the matter either. "but when FSA was also included, lead concentrations spiked to over 900 ppb."
"After pre-conditioning the meters with 200 flushings with 1.0 ppm CL water, seven different solutions were pumped for a period of 6 weeks. Water
samples were taken for lead analysis three times per week after a 16-h stagnation period. In the static testing with brass elbows, exposure to the
waters with CA + 50% excess NH3 + FSA, with CA and ammonium fluosilicate, and with CA + FSA resulted in the highest estimated lead concentrations. In
the flow-through brass meter tests, waters with CL + FSA, with CL + NaF, and with CL alone produced the highest average lead concentration for the
first 3-week period. Over the last 3 weeks the highest lead concentrations were produced by CL + NaF, followed by CL alone and CA + NH3 + FSA. Over
the first test week (after CL flushing concentrations were increased from 1.0 to 2.0 ppm) lead concentrations nearly doubled (from about 100 to nearly
200 ppb), but when FSA was also included, lead concentrations spiked to over 900 ppb." http://www.sciencedirect.com/science/article/pii/S0161813X07...AJKOER - 24-1-2016 at 12:38
My synopsis on various readings on water purification is that chlorine is good in the immediate killing of most deadly bacteria, but has it issues.
This is due in part by its reaction with water forming Hypochlorous acid and Hydrochloric acid:
Cl2 + H2O = HOCl + HCl
where the HOCl, the primary source of the disinfecting properties, is characteristically unstable (which upon decomposing, may add yet another acidic
HCl molecule). This limited life span could present an issue in older water distribution systems that have potentially recontamination issues.
To address the limited life span issue, one option is Chloramine, NH2Cl, which on hydrolysis:
NH2Cl + H2O = HOCl + NH3
But, unfortunately, it is a far weaker disinfectant than Hypochlorous acid. Per my personal experience, it is very hard to remove from water, and
there appears to be asthmatic issues associated with swimming pool exposure to Chloramine.
Back to Chlorine, my observation is that the products of the action of chlorine on a hydrocarbon are mostly always carcinogenic, although this seems
to be a more recent discovery in the science of safe drinking water. A more recent observation is how a very low dose of a soluble bromide salt in the
presence of HOCl and a source of hydroxyl radicals (like strong sunlight exposure at water reservoirs containing nitrate, or Cu2O coating in ones
Copper plumbing) can create highly carcinogenic bromates.
[Edit] A version of how the bromates could be created, first a series of radical based reactions forming Chlorate acid:
.OH + HOCl = H2O + .ClO
.ClO + .ClO = Cl2O2
Cl2O2 + HOCl = HClO3 + HCl (See Eq 8 "Effect of Chloride Ion on the Kinetics and Mechanism of the Reaction between Chlorite Ion and Hypochlorous
Acid" by Balazs Kormanyos, et al., 2008, at https://www.researchgate.net/publication/23141635_Effect_of_... ).
Next, a sequence of reaction creating the bromate:
[Edited on 25-1-2016 by AJKOER]neptunium - 24-1-2016 at 14:54
How about strong radioactive source exposure? Depending on the source it requires a one time purchase and a lifetime of fun without any chemicals
added to the water...
God knows there is plenty of powerfull source going arround. For a modest increase on the electric bill, you could use Xrays as well! No need for
source removal at all!!
[Edited on 24-1-2016 by neptunium]Dr.Bob - 24-1-2016 at 15:07
Y'all were right on the ppb not ppm for lead.
Radiation, mostly in the form of UV light can be used for disinfecting water, which is fine for point of use disinfection. But the problem in cities
is that the pipes can become contaminated or occasionally even get back wash from badly installed plumbing systems, so they need a persistent way to
keep bacteria and more from living in the water pipes. That is why chlorine was used and one reason that it works better at disinfecting than ozone,
because it is more persistent. In an ideal world, ozone or UV would be great, but neither works well in big cities, due to contaminants and biofilms
in pipes that can come back once the chlorine is gone. That is one reason they often will up the chlorine once a year in systems to help clean the
bacterial and fungal crap from the pipes.
One solution would be to have more decentralized disinfection rather than one or two water systems in a large town, just like multiple power grids are
more stable. But economy of scale wins on costs, so that just is not practical. And since people only drink a small fraction of the water in the
system (I think drinking is less than 0.01% of all total water usage, most goes for lawns, toilet flushing, showers, washers, etc), it is hard to make
all of the water "perfect", whereas if only the drinking water was to be treated, it would be trivial to make it clean and safe. Another simple
solution is to just buy a simple filtering system that removes solids, organics, chlorine, and salts, for the amount of water most people drink, that
is doable. I just stick to beer and soda.Morgan - 24-1-2016 at 15:51
Dr Bob, you mean ppb not ppm, don't you? I thought the EPA limit for lead in drinking water was 15ppb (parts per billion). The Virginia group
found some cases that were over 1000 ppb.
I think you're exactly right about inept bureaucrats.
I just heard Dr. Sanjay Gupta on CNN site 13,000 parts per billion!
Transcript
(on camera): One of the problems is that the Walters' house is one of the furthest away from the treatment facility. It partly explains why the
testing here was among the highest, 13,000 parts per billion. To give you context, five parts per billion would be cause for concern. 5,000 parts per
billion is related to toxic waste. This home, 13,000 parts per billion. http://www.cnn.com/TRANSCRIPTS/1601/22/cnr.06.html
[Edited on 24-1-2016 by Morgan]macckone - 25-1-2016 at 09:36
One note on ozone for disinfection is water is usually done at entry into the system and again in a distributed manner since ozone is not residual.Texium - 25-1-2016 at 09:55
Seeing stuff like this makes me feel very good to have a rainwater system. Due to acid rain, there could be traces of HNO3 and
H2SO4 present, but there is virtually no chance of heavy metal contamination since the water comes directly from the sky to my
tanks. Filtered with activated carbon, sterilized by UV, nice fresh water.
Also, if there is a member here who has the analytical equipment and free time necessary to do a thorough water analysis, maybe someone who lives near
Flint could obtain a sample of water to send to them. That way we can run an independent analysis of the water that hasn't been commissioned by any
special interests.Neuro- - 25-1-2016 at 13:08
if there is a member here who has the analytical equipment and free time necessary to do a thorough [insert substance here] analysis ...
If there are any, perhaps they would like some $ to run a test on stuff people make ?
If i had a GC, MS or NMR i'd have them working 24/7, churning out some $, and important information as well.feacetech - 26-1-2016 at 14:10
There are many impurities in potable water depending on the source and treatment.
Langelier Saturation Index
Larson-Skold Index
can explain some of these but not all.
Water can be scale forming (high Ca And Mg hardness) or corrosive depending on certain impurities. Some very pure waters can be quite corrosive (RO
water).
Remember everything will dissolve in water to some degree, even things that are stated as insoluble given enough time (directional pressure etc)
Water is an amazing chemical with many amazing proptites
First, I would raise the pH of the water. I own and on occasion have used a machine (MicroLite Jupiter Water Ionizer) that can make water more
alkaline, generally for taste reasons.
What is the mechanism these machines use to segregate high pH water
and low pH water? I envision an additive of some kind. You can't "ionize" pure water beyond its natural ionization state (10*-7). So the additives
become important as potential contaminants. I don't care much for drinking buffer solutions if that's what the result is. Have you tried evaporating
the water to see what mass is left and compared that to the residue from the input water? A good analytical balance would be key.chemrox - 26-1-2016 at 15:10
How about strong radioactive source exposure? Depending on the source it requires a one time purchase and a lifetime of fun without any chemicals
added to the water...
God knows there is plenty of powerful source going around. For a modest increase on the electric bill, you could use Xrays as well! No need for
source removal at all!!
I corrected your spelling for you.. I realize the spell checker here is a little light on vocabulary but
still...
so do you mean transmutation of Pb to Au? I believe the expense would be horrendous and not available using x-ray machines.feacetech - 26-1-2016 at 18:56
Have you tried evaporating the water to see what mass is left and compared that to the residue from the input water? A good analytical balance would
be key.
Or you could use conductivity to estimate TDS I have compared the two methods before in cooling water and found them to line up almost exactlyneptunium - 26-1-2016 at 20:14
How about strong radioactive source exposure? Depending on the source it requires a one time purchase and a lifetime of fun without any chemicals
added to the water...
God knows there is plenty of powerful source going around. For a modest increase on the electric bill, you could use Xrays as well! No need for
source removal at all!!
I corrected your spelling for you.. I realize the spell checker here is a little light on vocabulary but
still...
so do you mean transmutation of Pb to Au? I believe the expense would be horrendous and not available using x-ray machines.
Yes thanks I am not writing from home and this tablet is awkward .
No I meant a strong radioactive source externally mounted in the context of the bio sterilization conversation we were having.not the lead
contamination. In order to bypass the use of harsh chemicals. I know UV usually do the trick I was just pushing the envelope a little with more
ionizing radiation.
Nothing to do with transmutation . getting rid of the lead was not the subject.thanks for clarifying