Arsenic Reduction

[sandpond]

Just had my well tested and found the arsenic standards have changed since the last test. With a new family starting I have concerns with .036 mg/L of arsenic (lower than the .050 standard before Jan '06). The question I am teetering over is do I use a POU Cartridge for arsenic reduction (adedge is what would be sold to me) or a RO system?? Any advice? What are the yearly operating cost comparisons? The hardness is 121 mg/L so a softener could possibly be put in at a later date or do I need one now to make either of these two systems work?

 

[Bob NH]

Just had my well tested and found the arsenic standards have changed since the last test. With a new family starting I have concerns with .036 mg/L of arsenic (lower than the .050 standard before Jan '06). The question I am teetering over is do I use a POU Cartridge for arsenic reduction (adedge is what would be sold to me) or a RO system?? Any advice? What are the yearly operating cost comparisons? The hardness is 121 mg/L so a softener could possibly be put in at a later date or do I need one now to make either of these two systems work?

I am giving you information based on some research that I did for removing arsenic from water supplies in southeast Asia. I have not done anything related to household systems in the US.

0.036 mg/liter is not a level that creates imminent danger, but I would fix it if it were my well and my kids.

Your choices depend on a number of things and you need a complete analysis of the water. Some of the systems for removing arsenic involve adsorbing it on precipitated iron and filtering out the iron. Therefore, the amount of iron in the water is a factor in using those systems.

There are two different forms of arsenic compounds (I'm away from my references but my recollection is that they are arsenite and arsenate) and some systems remove only arsenate.

There are systems that use iron deposited on a granular substrate such as alumina or other mineral, and the mineral is thrown away when ir reaches capacity. The regeneration process is usually not something that a homeowner wants to do (sodium hydroxide (lye) and hydrochloric acid).

Whatever solution you select, I suggest separating your potable water (drinking and cooking) from the other uses so you don't have to treat it all. Brushing your teeth with it isn't going to be a problem at the level you report. Washing vegetables or running the dishwasher is not going to be a problem.

If you treat only the potable water, then your total usage and total operating cost should be low. You should do a comparison of the cost of just buying water for drinking and cooking. You can do that while you make the decision on the system. Look at the cost of fairly large quantities; not what you get in single gallon jugs at the grocery store.

Take the time necessary to compare and carefully evaluate systems that someone wants to sell you, and get some guarantees on removal effectiveness and operating cost. I don't know what systems are being sold for indivuidual homes.

Your hardness is near the upper limit of what water suppliers consider acceptable. You might have to soften it if you install an RO system.

 

[Sponsor]

 

[Gary Slusser]

First, no one should allow themselves to be SOLD anything! Especially when their health may be involved. Take responsibility for your decisions and BUY it, but don't allow yourself to be sold.

Second, no one knows water treatment equipment and its application limitations etc. better than those 'selling' it.

All the rest of the folks you talk to or listen to have nothing to offer but an uneducated opinion. Which means they don't know fact from fiction.

You need to find a local or internet dealer that has experience or has a supplier that has experience in treating arsenic. Then rely on them and do follow up testing. There are a number of approved treatments and all depend on the water quality, how much water will be used etc..

If you are going to treat for arsenic, you should treat all the water on a POE (point of entry) basis. The purchase price will be higher than POU (use) but the maintenance will be less and treatment is basically automatic with the least need for maintenance and ya can't forget or otherwise put off required maintenance like with a RO.

RO does not reduce all types of arsenic. No RO removes anything (like this) to zero.

Any dealer offering a guarantee is selling you, unless he maintains the equipment, and that is not necessary - you can simply do inexpensive scheduled/timely follow up tests.