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Although occurring naturally in rocks and soil, arsenic in its many forms can be very dangerous to our health.
In excess quantities the element has found its way into the environment including our ground and surface waters as a byproduct of mining and other industry sectors as well as agricultural use in fertilizers, pesticides and herbicides.
And what’s most dangerous about it is that, dissolved in water, arsenic can’t be detected by taste, odor or color.
How to remove arsenic from water? You are about to find out!
On This Page You Will…
|Model||Our Rating||Price||As(III) Red.||As(V) Red.||Type|
Home Master TMAFC-ERP - Our Favorite RO System
|$$||Partially||99.6%||Reverse Osmosis Under Sink Unit|
AdEdge AD2710S - Best Under Sink Arsenic Filter
|$||Up to 99%||Up to 99%||Iron Oxide Filter for Under Sink|
Megahome MH943SBS - Our Favorite Distiller
Berkey - Outstanding Countertop Arsenic Filter
Clearly Filtered - Our Favorite Arsenic Filter Pitcher
|$||99.6% Combined||99.6% Combined||Pitcher|
AFW CF2-4520-SD33 - Arsenic Whole House Water Filter
|$$$$||Yes||Yes||Whole House System Based on Iron Oxide|
AFW CF3-4520-RFAASD - Arsenic Whole House Water Filter
|$$$$||Up to 95+%||Up to 95+%||Whole House System Based on Activated Alumina|
Please remember that under sink drinking water filters require pre-treatment in case you are on a private well. A standard whole house filtration system usually does the trick.
Let’s start with the question: Does reverse osmosis remove arsenic?
Yes, it does. As studies have shown, reduction rates of up to 95% are realistic. However, this only applies to As(V). The removal of As(III) needs pre-oxidation to convert to As(V) which an RO system can then filter out. This additional step will increase the cost and complexity of the setup.
Our Favorite RO System: Home Master TMAFC-ERP
Read Our Review
Great Value for Small Budgets: APEC ROES-50
Read Our Review
Certified Filtration Process: Aquasana OptimH2O
Read Our Review
What are the advantages of reverse osmosis filtration?
The disadvantages of reverse osmosis are:
Filters that contain specialized iron oxide adsorption media are very effective at reducing both forms of arsenic (jump down if you want to learn more about this method).
One of the few available under sink filter cartridges: The AdEdge AD2710S.
The cartridge is standard-sized so it fits any industry standard 10″ filter housing (also available on Amazon).
What’s more, the AdEdge AD2710S is compatible with most reverse osmosis under sink systems for unmatched arsenic removal performance.
Alternatively, there is the Crystal Quest CQE-RC-04051 featuring “arsenic-selective resin“, whatever that means.
It was designed to filter arsenic V and arsenic III. Customers reported levels below the EPA’s allowable threshold of 10 ppb.
And lastly, a 3-stage drinking water filter system by Abundant Flow Water.
It makes use of activated alumina (learn more below) to reduce As(III), As(V) and fluoride.
A 1-micron sediment pre-filter traps particulates. The activated/catalytic carbon filter (stage 3) removes chlorine, chloramines and other chemicals, tastes & odors, and heavy metals including lead for healthier and better tasting water.
Distillation provides the cleanest water of all purification methods.
First, water is heated to its boiling point. As it vaporizes, it leaves almost all contaminants behind including both forms of arsenic and cools down in a cooling coil where it condenses back into its liquid form. The water is then collected in a separate container.
Our favorite distiller is the Megahome MH943SBS with outstanding customer feedback.
It can provide up to 1 gallon of distilled water every 5½ hours. It’s UL (Underwriters Laboratories) approved for the highest safety standards. And your water won’t touch any plastic parts so recontamination is out of the question.
What’s more, an activated charcoal post-filter traps any volatile chemicals.
On top of that, the carafe which collects the purified H2O is made from glass rather than cheap plastic.
For a full review of the Megahome MH943SBS, click here.
Berkey systems are gravity-fed water filters that rely on, well, gravity to force water through their purification elements.
The level of filtering is top-notch. Contaminants that will be eliminated include viruses, bacteria, heavy metals, VOCs, chlorine and many more.
In order to get rid of 99.9% As(V) and pre-oxidized As(III) make sure to use the optional PF-2 elements which are also certified to remove more than 97% of fluoride and last for 1,000 gallons per set of 2.
Other advantages of Berkey systems are:
By the way, size doesn’t matter. Travel, Big, Royal, Imperial… – all Berkeys work with the same filter elements.
The Big Berkey is the most popular model. It has the perfect size for a family of 4. At the same time, it’s not too bulky for most kitchens and still portable to be moved around.
Want all the details? Follow this link: best-osmosis-systems.com/berkey-water-filter-reviews/
The Clearly Filtered is our favorite arsenic pitcher filter and certified to remove 99.6% of it (presumably As(III) and As(V) combined although not specified). Filter cartridges are made in the USA and long lasting.
Apart from arsenic, they remove a whole bunch of potentially harmful contaminants. NSF Standards 42, 53, 244, 401 & 473 are met.
Clearly Filtered offers a lifetime guarantee on the pitcher which is to be used for municipal water only.
Pitcher, dispenser or faucet units – as far as Brita is concerned, the popular filters won’t have any effect on arsenic content. Unfortunately, the same goes for PUR.
Again, unless your arsenic level is over 500 ppb or you want to draw water for drinking or cooking from more than one tap in your home, whole house water treatment for arsenic removal is not necessary.
You should also keep in mind that choosing point-of-use over point-of-entry can save you hundreds, possibly thousands of dollars to spend elsewhere.
Anyway, opting for the right treatment method depends upon a variety of factors including arsenic(III) & arsenic(V) concentrations (obviously), water flow rate and the presence of other contaminants, primarily iron.
What role does iron play? Simply put, iron levels and iron-to-arsenic ratios in the source water are a primary consideration in the selection of the right treatment method:
Generally speaking, it’s always a good idea to get in touch with 2 or 3 water treatment companies near you. They can help you determine which option is best for your individual water situation.
What’s more, your water should be tested periodically to monitor arsenic concentrations to ensure timely filter media replacements.
With this treatment method which basically is an iron removal process, As(III) is oxidized to As(V) as the first step. This can be achieved using chemical additives such as chlorine, ozone or potassium permanganate. Due to the strong oxidizing properties, contact time is not a critical factor.
Please note: Aeration is not an effective method for oxidizing arsenic.
The filtering media that follows may consist of sand, sand and coal anthracite, or proprietary products like Pyrolox, Birm and manganese greensand. Backwashing of the filter media is required.
Coagulation/filtration is a very common and effective method for getting arsenic-free water. Metal salts, especially iron, are dissolved into the water causing the arsenic to coagulate (bind to the additive).
The newly-formed, larger solid particles can then be pressure-filtered. Pressure filters require backwashing.
Next we have adsorption media filters which is the industry standard for arsenic removal. They make use of granular iron (hydr)oxide-based media housed in large tanks which trap, or adsorb, arsenic in their tiny surface pores – similar to how activated carbon works.
Titanium and different kinds of hybrid media that contain iron-impregnated resin are also highly effective.
The media bed removes arsenic until it’s exhausted. This is why regular media replacement are mandatory.
Similar to a water softener, an anion exchange system relies on a resin bed housed in a large tank to remove the pentavalent form of arsenic from water. The process will not affect arsenic(III) unless it is first oxidized.
How exactly does the process work? As water passes through the tank, the arsenic replaces chloride ions attached to the resin which becomes exhausted over time.
Eventually, it needs to regenerate by backwashing with a supersaturated sodium chloride solution. The chloride strips the embedded arsenic molecules of the resin which are then flushed out with the wastewater.
One of the few anion exchange whole house arsenic removal filters we could find is the WECO A33E-0948 that relies on FERRIX A33E resin.
It operates a little bit different from the process explained above: Instead of using water supersaturated with sodium chloride for backwashing it simply uses plain water.
The good news is that the system is suited for municipal and well supplies. In addition, you can choose from a variety of sizes to meet your needs in terms of flow rate and filtering capacity.
Also, the Fleck 5810 XTR2 touch screen control valve is easily programmed, user-friendly and comes with plenty of setting options. Built-in bypass valve – check! Stainless steel outer jacket for durability – check!
The bad news is that the WECO A33E-0948 is pretty expensive.
Flow rate: 6 gallons per minute.
Last but not least, activated alumina, or short AA.
Although more effective at removing pentavalent arsenic, AA adsorption works for both arsenic(III) and (V) with achievable reduction rates of more than 95%.
Additional benefits are that activated alumina will also remove any fluoride that might be lurking in your water. Plus, it’s easy to handle because there’s no wastewater and backwashing.
One example of a whole house filtration system that works with activated alumina is the Abundant Flow Water CF3-4520-RFAASD with 20-inch heavy duty Big Blue housings for fast flow rates.
In fact, the system uses a blend of activated alumina and bone char to tackle arsenic of up to 15 ppb.
The additional filter stages eliminate tastes, odors, chlorine, chloramines, pesticides, herbicides, organics, MTBE and THM for the healthiest water possible.
A sediment pre-filter traps particulates down to a size of 5 microns to protect the system from clogging.
On the downside, customers had issues with leaks and complained about the installation instructions that lack the necessary level of detail.
First of all, no water treatment method can ever truly eliminate 100 percent of a specific contaminant.
That being said, with arsenic (As) removal the goal should be to reduce your intake from drinking water as much as possible.
Regular activated/catalytic carbon filtration won’t help you here. Removal capabilities are insufficient.
However, other treatment methods have shown very promising results including:
Please note: Additional pre-treatment may be required, particularly if you are on a private well.
It is also important that we distinguish between arsenic(III) a.k.a. As(III) and arsenic(V) respectively As(V) in the source water. The latter which is the pentavalent form of arsenic can be removed pretty easily by most filter systems. Arsenic(III) requires a more sophisticated approach.
Which of the two you might be facing depends on the amount of oxygen in the source water. Higher oxygen levels usually lead to increased arsenic(V) concentrations and less of arsenic(III).
This has do to with oxidation and applies to groundwater but also to municipal supply systems which oftentimes treat their water with chlorine for disinfection. Chlorine as a common oxidation agent oxidizes arsenic(III) to arsenic(V).
FYI: We will discuss oxidation and its role for the removal of arsenic(III) in a bit.
But first you must decide if you prefer point-of-use (POU) or point-of-entry (POE) treatment. As the name suggests, POU filtration provides clean water at a single tap only such as your kitchen sink, whereas POE is a synonym for whole house applications.
If all you want is treat arsenic in your drinking water and nothing else, installing a relatively inexpensive under sink filter is the most straightforward solution. Of course, in this case you can’t drink from any faucet in your home but one.
On a side note, a valuable alternative to POU filtration is distillation which we are going to cover in this guide as well.
And don’t worry, unless your arsenic level is really high (over 500 ppb), showering, bathing and other household uses are safe. Arsenic is not absorbed through the skin, neither does it evaporate into the air.
If you insist on whole house filtration though, be prepared to invest a bit more for a water treatment solution that really works.
More on Arsenic Filtration
Given the fact that tap water contaminated with arsenic is being served to millions of Americans each year – not to mention the people that receive their water from a polluted well – searching for ways to have the metalloid removed from our water at home feels like a worthwhile endeavor.
How many people are affected? 71 million living in 46 states, according to the EWG. That’s almost 7,000 water utilities in total. And that is for tap water alone! Of course, private wells are equally affected.
By the way, yes, there are federal drinking water standards that define the highest level of arsenic allowed. It currently is 10 parts per billion (ppb) set by the EPA (used to be 50 ppb before January 2001).
FYI: 10 ppb = 10 µg/L (micrograms per liter)
However, due to the fact that arsenic is a cancer-causing pollutant the non-enforceable federal health guideline is 0 ppb. The guideline defined by the California Office of Environmental Health Hazard Assessment is 0.004 ppb which is considered as not posing a significant health risk.
The number of people served over the legal limit? 415,000 spread all over the country.
*Numbers from 2015
Arsenic in U.S. Groundwater – Credit: U.S. Geological Survey
Speaking of health risks, arsenic is a naturally occurring mineral. But it is also a known carcinogen associated with skin, lung, bladder, kidney and liver cancer. Other health concerns are:
Did you know that food not water is the main cause for arsenic exposure in the U.S.?
In other words, our diets play a major role when trying to reduce the amount of arsenic we ingest on a daily basis.
The biggest culprit: Rice and rice-based processed foods including cereal, pasta and rice milk. This is because rice plants accumulate arsenic from water and soil.
Testing conducted by Consumer Reports showed that more than 200 samples of rice products contained measureable amounts of arsenic, many at worrying levels, both in inorganic as well as organic forms.
Bottom line: Removing arsenic from your drinking water is a great start, but don’t underestimate the potential impact of your diet.
The easiest way to find out if there is any arsenic present in your tap water is by checking the EWG Tap Water Database. Simply enter your zip code and you will be shown a list of suppliers that serve your area and the surrounding county. Click the name of your utility to learn about all the contaminants that were found in your water supply between the years 2010 and 2015.
Another option is to contact your supplier directly and ask for a free Water Quality Report.
What do you do, however, if you are on a private well? One way to go about this is to reach out to your local health department. The staff will be able to tell you whether or not arsenic is a problem in your area.
If you want absolute certainty you should have your water tested by an accredited laboratory for a small fee. You will receive a test kit with all the instructions that you need.
Or you can do the testing yourself. A variety of test strip kits are available that allow for easy, cheap, fast and relatively accurate testing. Tip: You want to look out for kits that provide useful arsenic detection levels like 1, 2, 3, 4, 5, 10, 20 and 50 ppb.
What’s more, there are a couple of things that you should consider when collecting your water sample, such as:
Unfortunately, heating or boiling water will not remove arsenic. In fact, due to evaporation arsenic concentrations can actually increase.
If you have any questions about arsenic removal from water please don’t hesitate to leave a comment below!
And don’t forget to come back to this page from time to time, as we are going to add new filters occasionally.
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