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arsenic and other pollutants in Lermer-Chapala aquifer

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According to an article in today's Mexico News Daily (mexiconewsdaily.com), in 2001 arsenic and fluoride in the Lermer-Chapala aquifer were in "concentrations 10 times greater than what are deemed tolerable limits for human consumption," and now "concentrations [of pollutants] have doubled in some places, and arsenic--a carcinogen--has been recorded at 20 and up to 30 times over its acceptable levels." Does anyone have information about the levels of arsenic and other pollutants in tap water at Lakeside?

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I don't believe that tap water in Lakeside comes from the lake at all but from wells. I've heard that there is arsenic in the water in Chapala but not further west. Guadalajara draws some of it's water from the lake.

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Yes water comes from wells lakeside. I had my Upper Ajijic water tested and it was very hard but safe. Depending on where you are your results may vary. My well is well above the lake and fed from the mountains. Do some reading about this if concerned and do a test. You may want to switch to reverse osmosis or other methods. These are not simple things to remove. Our normal filter systems here will not remove arsenic/fluoride from water. This being the particle filter feeding into a charcoal filter going to UV light. FYI most jug water here is reverse osmosis so you folks who buy good water are safe. Note I said good jug water!! Not a good place to save money unless you have your own water tester meter which many folks do have to check out bottled water. Note Calcium and Sodium show up on results for meter so you could have a sky high reading that is harmless from city water. Results from Bottled water should be close to zero as possible.

Go read about this on the internet. Google " Can I remove arsenic/flouride from my drinking water".

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Yes water comes from wells lakeside. I had my Upper Ajijic water tested and it was very hard but safe. Depending on where you are your results may vary. My well is well above the lake and fed from the mountains. Do some reading about this if concerned and do a test. You may want to switch to reverse osmosis or other methods. These are not simple things to remove. Our normal filter systems here will not remove arsenic/fluoride from water. This being the particle filter feeding into a charcoal filter going to UV light. FYI most jug water here is reverse osmosis so you folks who buy good water are safe. Note I said good jug water!! Not a good place to save money unless you have your own water tester meter which many folks do have to check out bottled water. Note Calcium and Sodium show up on results for meter so you could have a sky high reading that is harmless from city water. Results from Bottled water should be close to zero as possible.

Go read about this on the internet. Google " Can I remove arsenic/flouride from my drinking water".

.

"You may want to switch to reverse osmosis or other methods. These are not simple things to remove. Our normal filter systems here will not remove arsenic/fluoride from water. "

Note that arsenic is very easy to remove from drinking water using the common method of using activated carbon. Only the simplest wound-string sediment-filter-only systems cannot remove arsenic. Pretty much all other drinking water treatment systems include either activated carbon or RO that easily remove ALL arsenic.

e.g. The simplest Brita pitchers and Brita faucet filters remove arsenic with activated carbon, Pur's little faucet filters on your kitchen sink tap remove all arsenic using activated carbon, etc.

Fluoride removal is more difficult, as activated carbon is not sufficient. It takes RO to remove fluoride.

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Guadalajara draws some of it's water from the lake.

Nobody in Guadalajara drinks unfiltered tap water,not even poor people,they buy garrafones,unless they want "tripas torcidas".

.Fluoride removal is more difficult, as activated carbon is not sufficient. It takes RO to remove fluoride.

"Do you realize that flouridation is the most monstrously concieved and dangerous communist plot we have ever had to face?"

General Jack D Ripper.

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Snowyco I found some disagreement about whether our normal charcoal filters will do the job. Many sites suggest RO. Thus what I posted. Found enough negative references to make me question whether it is sufficient or not. One site said R.O. or Distillation only. Not saying I know just what I found. On the official Oregon health department site it does not even mention filters as a treatment for arsenic in drinking water. Guess I am confused now. Also some sites suggest special arsenic filters before normal filters.

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Filtration does not remove chemicals in solution; only particles.

Wells penetrate aquifers; so if the arsenic is in the aquifer, it is also in well water.

There seem to be some misunderstandings.

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When I had the city water tested it was considered safe. Wonder if different wells get water out of different locations underground. When I use a TDS meter I see 650ppm before home water treatment in upper Ajijic. I measured 350ppm in La Floresta so the water must vary from well to well right??

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When I had the city water tested it was considered safe. Wonder if different wells get water out of different locations underground. When I use a TDS meter I see 650ppm before home water treatment in upper Ajijic. I measured 350ppm in La Floresta so the water must vary from well to well right??

Conceivably, every well could have different water.

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We need to look at water delivery service, suggestions please on where to order "good water".

We have been using Kayta water, locally owned, for many years. So do many local restaurants.

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I sent the article to Dr. Stong, and this is his reply:

Thanks for sending me this article about claims of danger on many fronts with well water in Mexico.

It seems (1) the claimed area of concern is in other Mexican states, not Jalisco; (2) further it is in a very small area of 800 sq km which equals a square 17 miles on a side in a very, very large river basin; (3) note that with the area of the Lerma-Chapala River basin being 54,400 km2 this area of focuse area of 800 km2 = 800/54400 = 1.4% of that basin.

This article by the for profit university in Guadalajara appears opening paragraphs to wish to not make it clear that the wild numbers being presented may not apply to over 98% of the basin, and in particular not to Jalisco. Regretably, these alarmist proclamations, “bad news” endure for long periods and they confuse many. Sadly, this is why after years of these “the sky is falling” cries that attention is lacking when a real wolf appears. In my 14 years of testing in and about the lake I would guess that 80% of the Mexicans, due to few that read, and 60% of the foreigners, who have no inclination to dig deeper, believe the lake and water systems are not safe – exceed limits for various minerals and substances. That is not so. As noted as long as the lake is more than 30% full it is my belief that no substance in the lake exceeds limits. Even pure water and salt while much needed by the body can lead to death in less than an hour if taken too much. That is there is a “safe” limit set today for the majority of substances that we encounter. Even some heavy metals in very small amounts are desired for health. But, since they are such small amounts it is best to advise the public to stay away, only a trained medical person should prescribe a dosage if needed.

The Mexican limit for arsenic is 25 parts per billion (1 kg in 4000 dump truck loads of materias). The US limit before 2001 was 50 ppb. In the city of Chapala I have know for over 10 years that there are about 4 of the 6 wells that test out at about 35-40. You may note some skin rashes on the people, especially in the north of the town. I have not found anything about Lake Chapala higher than 40 ppb. North of Jocotepec I found “some” in the village water reports, but nothing high. The Ajijic area has perhaps the best well water on the lake. Most of the Southwest of the USA has private wells that exceed 30 ppb and neither the government or the citizens are taking action. Many feel the 50 ppb limit was sufficient. Thus, claims of arsenic levels that are 10 times the limit appear questionable.

Please understand that measuring substances in parts per billion is difficult. At that university it is common for many different persons to attempt to use the $100,000 equipment (atomic emission spectrometry) and thus there can be a multitude of errors. Further, as best I have heard there is little to no effort to calibrate the testing machine. That is why for the past 10 years I have had to use licensed/certified commercial labs to conduct tests of heavy metals that are nearly all measured in parts per billion. In such labs, one person mother’s that very delicate machine, and he begins each day with a calibration.

The reason for above levels of arsenic in Mexico and the Southwest USA is the volcanic nature of most of the lands. Mexico is the #3 exporter of arsenic in the world. In the earth’s crust arsenic is 1800 parts/billion, thus you can imagine if in some places it being at 25 parts/billion in water.

In various Latin American countries such as Argentina, Chile, Mexico, El Salvador; Nicaragua, Peru and Bolivia, at least four million people drink water containing arsenic at levels which pose a risk to their health to such an extent that in certain areas this has become a public health problem.”

Arsenic is used in shampoos and even some medications. Note: “Despite its potential toxicity, arsenic is also an essential element, necessary to our physiology. A level of 0.00001% is needed for growth and for a healthy nervous system.”

As to fluoride, I have been working at the invitation of village leaders with a Mexican “hippy” village of about 100 persons near Tala, just west of Guadalajara, that does have a fluoride level that is 5-10 times the limit! These people in a wish to get away from the world, “to live off the grid,” purchased a plot of land that turns out to be a volcanic ash pile 100s of feet deep. I took their water back to be tested in the USA and on finding the results advised them to immediately stop drinking the water. Since then I have tried to have them agree to creating a bottled water system that would use the reverse osmosis process to remove the arsenic. Being all quite individual beings, with more intellect than logic they have yet after 2 years not moved on this challenge!

Note in a newspaper of a few days ago in Nov 2015 that wells were tested by 2 other labs that seem to suggest no issue as claimed by this university group.

Tag: Conagua , Humberto Navarro , Marcos Adrián Ortega Guerrero , San Jose Iturbide , UNAM Communities Northeast Differ on well water potability of La Cantera November 26, 2015 The water was analyzed by two laboratories: ABC Analytics and IBESA; both agreed that the water poses no risk.

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Filtration does not remove chemicals in solution; only particles.

Wells penetrate aquifers; so if the arsenic is in the aquifer, it is also in well water.

There seem to be some misunderstandings.

.

" Filtration does not remove chemicals in solution; only particles. "

This claim is absolutely incorrect and false.

Reverse osmosis, ion exchange, adsorption (activated carbon), and adsorbents do well at removing arsenic from drinking water.

When properly maintained: These kinds of filtration methods can remove almost ALL "chemicals in solution", reliably producing good clean safe drinking water.

Common filtration using activated carbon works well at removing most common contaminants, as long as the filter is not overloaded with too many contaminants. Activated carbon filters have a HUGE but finite number of active adsorbant sites, which means the activated carbon filters are excellent at removing large organic molecules (like dissolved pesticides, herbicides, dyes, and industrial solvents).

This same property means: Activated carbon filters are modestly efficient at removing heavy metals (like Ni, Cd. Cr, As, & Pb), but are very poor at absorbing small metal ions in water (like Na, Ca, Mg, etc).

Back to Arsenic contamination in drinking water:

Arsenic in drinking water typically comes from iron-bearing rocks, mine tailings, or from agricultural run-off pollution.** The chemical form of arsenic present in the water is critical in knowing if activated carbon will remove all of our arsenic in water contamination.* Arsenic exists in primarily two oxidation states (two common species) in natural water samples: arsenic+3 => As(III) ~ and arsenic +5 => As(V).

As (III) is roughly 10X more toxic to animal and plants than As(V). ... Activated carbon removes As(V) more efficiently than As(III).

But: When Iron +3 => Fe(III) is present in drinking water, it oxidizes/converts the As(III) to As(V) - making the Arsenic easily adsorbed by activated carbon.

This means that some internet "studies" mistakenly add As*(III) to the water for their activated carbon testing - and they mistakenly report that activated carbon did not work well. => The species/form of arsenic is critical to knowing if activated carbon will work.

This means that when our water has iron (from iron pyrite mineral rocks or arsenopyrites), our water contains the form of Arsenic that is well-adsorbed by activated carbon .

https://books.google.com.mx/books?id=hMA70VU36qUC&pg=PA104&lpg=PA104dq=is+arsenopyrite+As%28III%29+or+As%28V%29&source=bl&ots=AN5jnkqbZY&sig=9ObrKs01Ns3VNmvCKge7PNO-Ggw&hl=en&sa=X&ved=0ahUKEwjXsIO38b_JAhUJOCYKHYMEAN0Q6AEIOjAG#v=onepage&q=is%20arsenopyrite%20As%28III%29%20or%20As%28V%29&f=false

"Application of Activated Carbon for Removal of Arsenic Ions from Aqueous Solutions, RANSARI* and M SADEGH, Chemistry Department, Guilan University, Rasht, Iran POB 41335-1914, E mail: ransari@guilan.ac.ir, Received 26 August 2006; Accepted 3 October 2006"

================================

Human-caused arsenic pollution can almost always be traced to mining or mining-related activities or agricultural run-off (from fertilizers, herbicides, fungicides & pesticides).

*http://www.ncbi.nlm.nih.gov/pubmed/18982996

**http://water.usgs.gov/nawqa/trace/pubs/gw_v38n4/

==========================

Finally, to answer LCScats concerns:

Small kitchen-sink faucet filters may have limited capacity to absorb arsenic, especially high concentrations of As(III).

(but NOTE that our waters likely have enough Iron(III) to convert the As(III) over to As(V) that IS adsorbed by activated carbon)

In any case, the little kitchen-sink faucet-filters have such small amounts of activated carbon, that they must be changed FAR more frequently than the big cartridge activated carbon filters, because the kitchen-filters adsorbent sites get "filled" by contaminated water. ... If you have fairly clean (not-heavily contaminated) drinking water, the kitchen filter lasts much longer than when it has to filter modestly-contaminated water - but typical home water-filtration system activated carbon cartridges work for a long time.

http://pubs.acs.org/doi/abs/10.1021/bk-2005-0915.ch020

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Snowy:

Filtration Definition: Filtration is a mechanical or physical process to separate solid particulates from fluids.

Adsorption or reverse osmosis processes are not technically filtration.

Activated carbon can both filter and adsorb. Reverse osmosis is a membrane separation process that blocks the transport of dissolved salts across the membrane leaving potable water. We don't use RO "filters" for removing solid particulates as they become fouled quickly.

This is why full water treatment starts with the separation of solid particulates and then progresses to the removal by adsorption or RO of dissolved pollutants.

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Thank you. That is exactly the situation, and you explained it well.

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Kayta, Santorini, and Ciel bottled water tested fine with my TDS meter when I bought bottled water. Never tested others brands.

Which elements/compounds/pathogens does a TDS meter test for? Can specific elements/compounds/pathogens be isolated and quantified, i.e. how many of what?

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Which elements/compounds/pathogens does a TDS meter test for? Can specific elements/compounds/pathogens be isolated and quantified, i.e. how many of what?

Total dissolved solids-nothing more.
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Thanks for taking the time Snowco to explain what I saw and it makes perfect sense now. Also thanks to the person who wrote Dr. Strong.

So is anyone going to test our city water in Ajijic??

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Most people won't want to go to the expense of testing Ajijic's water. It is mainly used for bathing, clothes washing and lawns. The water in the decrepit lines is not the same quality as the water in the wells.

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Yo1, you said "I don't believe that tap water in Lakeside comes from the lake at all but from wells." That is the aquifer that the report was speaking of, arsenic is absorbed through the skin while showering.

 

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