Black Berkey Elements and Berkey Phoenix Filter Elements, the current standalone replacement element, have each been independently lab tested against pharmaceutical drugs and hormone-related compounds. Between the two elements, 20 distinct compounds have verified reduction data, each above 99.5%. This article shows exactly which compound was tested on which element, how pharmaceuticals and hormones get into drinking water in the first place, and why private wells are especially exposed.
Quick answer: Yes. Black Berkey Elements have independently verified data on 17 pharmaceutical and personal-care compounds, each reduced by more than 99.5%. Phoenix Filter Elements have separate independently verified data on 14 compounds, each reduced by more than 99.9%, including estrone, a form of estrogen. Some compounds overlap between the two tests and some don't, so the full comparison table below is worth checking for the specific compound you're asking about. Estradiol, a different and more commonly discussed form of estrogen, has not been independently tested on either element.
How Pharmaceuticals and Hormones Get Into Drinking Water
Pharmaceutical drugs and personal care product chemicals are classified by the EPA as emerging contaminants: pollutants that are increasingly detected in water sources at low levels, but whose long-term health effects are still being studied. Of the roughly 250 million pounds of pharmaceutical waste generated each year, a large share comes from hospitals and care facilities, with the rest from households and veterinary sources, including livestock treated with growth hormones or veterinary medication.
Most of these chemicals enter water indirectly. Rather than being flushed directly, drugs and hormones are excreted by the body and enter wastewater through normal use. Estrogens, for example, appear in wastewater largely as estrone and estradiol, both of which can be excreted after use of hormonal contraceptives. Wastewater treatment plants are not generally equipped to remove most of these compounds before discharging treated water back into rivers and lakes, some of which supply municipal drinking water downstream.
Why Private Wells Are Especially at Risk
Households on private wells typically also rely on private septic systems to treat their own wastewater, which creates a shorter, more direct path between a household's own pharmaceutical waste and its own drinking water supply. Research led by Dr. Heather Gall, an assistant professor at Pennsylvania State University who studies contaminants of emerging concern in groundwater, found that whether a given drug reaches groundwater depends mainly on two properties as it filters through the soil in a septic drain field.
The first is sorption potential: how readily a compound binds to soil particles rather than continuing to travel with the water. In Gall's study, which sampled water from 26 private wells through the Pennsylvania Master Well Owner Network, the antibiotic ofloxacin had the lowest sorption and was the most frequently detected drug in the wells tested. Naproxen, by contrast, had the highest sorption and was not detected in any sample, because it tends to stay trapped in the drain field soil rather than reaching groundwater.
The second is biodegradability, measured as the compound's half-life in the environment. Ofloxacin, the most commonly detected drug in the study, has a half-life of about four years. Caffeine and acetaminophen, by comparison, have a half-life of less than a day and were found in less than half of the samples tested. The Penn State findings indicate that septic systems can measurably affect the water quality of the private wells they sit near, though the drug concentrations detected in that particular study were low enough that the researchers characterized the health risk as minimal.
Where this leads: Roughly one in five septic systems in the US does not function as designed, which increases the odds that poorly biodegradable, low-sorption compounds reach the groundwater that feeds a nearby well. A well's vulnerability depends on its specific soil type, depth, and distance from the septic drain field, not just on whether a septic system exists nearby.
The Cape Cod Case Study: What Silent Spring Institute Found
A separate, earlier study by the Silent Spring Institute tested this same septic-to-well pathway directly. Researchers led by Dr. Laurel Schaider collected water samples from 20 private drinking wells across Cape Cod, Massachusetts, and tested each for 117 pollutants. All of the sampled wells were in areas served by septic systems, and roughly 85% of Cape Cod households rely on septic treatment.
The results: about 70% of the wells tested positive for PFAS compounds (referred to in the original study as PFCs), a class of fluorinated chemicals linked to developmental effects and commonly found in non-stick cookware, stain-resistant fabrics, and waterproof clothing. Separately, 60% of the wells tested positive for at least one pharmaceutical drug, most commonly the antibiotic sulfamethoxazole and the anticonvulsant carbamazepine, and 25% contained flame-retardant chemicals. Wells with higher nitrate levels also tended to have more contaminants overall and at higher concentrations, which the researchers noted could make nitrate testing a useful, low-cost early indicator of broader septic-related contamination, even though nitrate itself does not directly predict which specific pharmaceuticals are present.
A specific limit worth knowing: The EPA sets an enforceable drinking water limit for nitrate (10 mg/L, measured as nitrogen), but at the time of the Cape Cod study there was no equivalent federal limit for the pharmaceutical or PFAS compounds it detected. Some of those wells had nitrate concentrations below 1 mg/L, well under the health standard, while still testing positive for PFAS and pharmaceuticals, which is why a passing nitrate test alone cannot confirm a well is free of these specific compounds.
Does Berkey Remove Pharmaceuticals and Hormones?
Black Berkey Elements and Phoenix Filter Elements have each been independently lab tested for pharmaceutical drugs and hormone-related compounds, using two separate labs and two different test conditions. Black Berkey testing (Envirotek Laboratories, Report #14-260) challenged the element with roughly 20 to 21.5 µg/L of each compound and measured reduction to below a 0.1 µg/L detection limit, at least 99.5% reduction. Phoenix testing (RAYNU Analytical and Research Lab, Report #2510041B, September 2025, initial-stage results per NSF/ANSI 401 test methodology) challenged the element with a much higher 1,000 µg/L of each compound and measured reduction to below a 1 µg/L detection limit, at least 99.9% reduction. Because the two tests used different labs, different influent concentrations, and different detection limits, the results are not a direct apples-to-apples percentage comparison, but both independently confirm strong reduction for every compound tested.
Several compounds were tested on both elements, including sulfamethoxazole, carbamazepine, ibuprofen, and diclofenac sodium, the same drug classes identified in the Cape Cod and Pennsylvania well studies above. Others were tested on only one element. The full list is below.
Scroll table to see all columns
| Compound |
Black Berkey |
Phoenix |
| Antibiotics |
| Ciprofloxacin HCl |
>99.5% |
99.9%+ |
| Erythromycin USP |
>99.5% |
99.9%+ |
| Sulfamethoxazole |
>99.5% |
99.9%+ |
| Trimethoprim |
>99.5% |
99.9%+ |
| Pain Relievers (NSAIDs / Analgesics) |
| Ibuprofen |
>99.5% |
99.9%+ |
| Naproxen Sodium |
>99.5% |
Not yet tested |
| Diclofenac Sodium |
>99.5% |
99.9%+ |
| Acetaminophen |
>99.5% |
99.9%+ |
| Anticonvulsants |
| Carbamazepine |
>99.5% |
99.9%+ |
| Phenytoin |
Not yet tested |
99.9%+ |
| Primidone |
>99.5% |
Not yet tested |
| Cardiovascular |
| Atenolol |
Not yet tested |
99.9%+ |
| Hormones |
| Progesterone |
>99.5% |
99.9%+ |
| Estrone |
Not yet tested |
99.9%+ |
| Other Pharmaceutical / Personal Care Compounds |
| Caffeine |
>99.5% |
Not yet tested |
| Triclosan |
>99.5% |
99.9%+ |
| Bisphenol A |
>99.5% |
99.9%+ |
| Gemfibrozil |
>99.5% |
Not yet tested |
| 4-para-Nonylphenol |
>99.5% |
Not yet tested |
| 4-tert-Octylphenol |
>99.5% |
Not yet tested |
Sources: Envirotek Laboratories, Report #14-260 (Black Berkey Elements); RAYNU Analytical and Research Lab LLP, Report #2510041B, September 2025, initial-stage results (Phoenix Filter Elements, product code PGF9-2).
What to Do If You Have a Private Well
Private wells are not subject to the same routine testing requirements as public water systems, so the responsibility for verifying water quality falls on the homeowner. A few concrete steps reduce the risk described above:
-
Test your well water annually for standard contaminants like nitrate and bacteria, and periodically for a broader emerging-contaminant panel if you rely on a septic system, especially if your well is shallow or close to the drain field.
-
Maintain your septic system on the manufacturer or local health department's recommended inspection and pumping schedule. A poorly functioning septic system is the primary pathway these contaminants use to reach groundwater.
-
Dispose of unused medications properly through a pharmacy or community take-back program rather than flushing them or discarding them in household trash.
-
Filter your drinking water with a system independently tested against the specific contaminants you are concerned about, and confirm the testing data before assuming a filter covers a given compound.
Frequently Asked Questions
Do Berkey water filters remove pharmaceuticals and hormones?
Yes. Black Berkey Elements have independently verified data on 17 pharmaceutical and personal-care compounds (Envirotek Report #14-260, each reduced more than 99.5%), and Phoenix Filter Elements have separate independently verified data on 14 compounds (RAYNU Report #2510041B, each reduced more than 99.9%). Combined, 20 distinct compounds have verified data across the two elements. Not every compound has been tested on both, so check the full comparison table for the specific compound you're asking about.
How do pharmaceuticals get into drinking water in the first place?
Most pharmaceutical and hormone compounds enter water indirectly, excreted by the body after normal use and carried through wastewater. Wastewater treatment plants are not generally equipped to remove most of these compounds, so trace levels can reach rivers and lakes that supply drinking water, or, for private wells, leach through septic drain fields into groundwater.
Are private wells more at risk for pharmaceutical contamination than public water?
Private wells can be more directly exposed because a household's septic system discharges effluent close to its own well. Research from Pennsylvania State University found that a drug's likelihood of reaching groundwater depends on its sorption potential and biodegradability, not simply on proximity to a septic system. Public water systems, by contrast, are centrally treated and routinely tested, while private wells are the homeowner's responsibility.
What did the Cape Cod well water study find?
Silent Spring Institute researchers tested 20 private wells across Cape Cod, all in septic-served areas, for 117 pollutants. About 70% tested positive for PFAS compounds and 60% tested positive for at least one pharmaceutical drug, most commonly sulfamethoxazole and carbamazepine. Wells with higher nitrate levels tended to have more contaminants overall, though nitrate alone does not confirm which specific compounds are present.
Is my well water safe if it passes a standard nitrate and bacteria test?
A standard test confirms nitrate and bacteria levels, but most emerging contaminants like pharmaceuticals, hormones, and PFAS are not part of that basic panel. The Cape Cod study found wells with nitrate well below the health standard that still tested positive for pharmaceuticals and PFAS. A broader panel is worth considering specifically if your well is on a septic system.
What is the difference between Black Berkey and Phoenix elements for this?
Black Berkey Elements have published data on 17 pharmaceutical and personal-care compounds, tested at roughly 20 to 21.5 µg/L influent concentration, each reduced more than 99.5%. Phoenix Filter Elements, the current standalone replacement, have separate published data on 14 compounds, tested at a higher 1,000 µg/L influent concentration, each reduced more than 99.9%. The two elements share 11 tested compounds in common, and each has some compounds the other does not, so the full table on this page shows exactly what's verified for each.
How often should I test a private well for pharmaceutical or hormone contamination?
Standard nitrate and bacteria testing is generally recommended annually. A broader emerging-contaminant panel covering pharmaceuticals, hormones, and PFAS is a reasonable addition if your well relies on a septic system, particularly a shallow well or one close to the drain field, even without a specific reason to suspect contamination.
What should I do with unused or expired medication to protect my water?
Use a pharmacy or community medication take-back program rather than flushing medication or discarding it in household trash. This reduces the amount of pharmaceutical waste entering wastewater and, for septic-system households, groundwater.
See the Full Contaminant Testing Data
Review complete independent lab reports for Black Berkey and Phoenix elements, or shop the current replacement filter elements.
See our full independent media coverage and Phoenix lab results page for additional third-party testing context.
Written and reviewed by Dan DeBaun, owner of BigBerkeyWaterFilters.com, an authorized Berkey dealer since 2008. See our
media coverage for independent verification of testing and company credentials.
By
Dan DeBaun
When will you be testing for estradiol i usually get my clients to use a reverse osmosis filter but it would be really convenient if they could use Berkey as well but it must be proven to remove estradiol or it is a complete waste of their money
Hi Kate -
Right now testing for estradiol is not planned. We will make a request for testing for this, but cannot guarantee it will be done any time in the near future.
Thanks
Dan
Ok so you use graphene to filter the water. Does any of that graphene end up in the water that is filtered by berkey filters? What happens to the graphene when this water is consumed? We have 99.93% of the vaccines for covid also have this graphene in them and its deadly. Using a deadly item to filter our water sounds like we are trading pharmaceuticals for graphene..and this is not good or even safe.
Hi Jodie -
I'm not sure where you've heard that the filters use graphene. This is not the case.
Thanks
Dan
How can you make that comment. It's truly misleading. It's like saying. Yes it removes the contaminates, but we don't have the proof because we haven't done the proper testing. With that said you just like the vaccine testing. They say yes it's safe but no testing has been done to prove that it's not safe. ,"It's called double talk." Really? Understand we who have our health at State want a proven yes or no. No in-between yes or no. If you won't do the research we can take it your main objective is $$$ and not the capabilities of your product.
Remember it's YES or NO. Most hpeople have no choice about the vaccines. But they have a choice with the purchase of a water filtration system.
just a correction on what you said,, we do have a choice about vaccines. don’t take them. don’t you allow anyone to put anything into your body without your consent.
I was advised by my GP to stop drinking distilled water and buy a Berkey water filtration system. I'm located in Florida and heavy metals are an issue. But since our water comes from the infamous aquaphor system and for taste they in scrupulously add toilet water, nd we are forced to utilize I am searching for a Berkey that will do the best job possible. Can you recommend what and where to purchase an appropriate Berkey water filtration system. Thanks.
Hi Lydia -
Any of the systems that come standard with the black berkey filters will do the job for you. You just would want to pick the size that suits your needs best.
Thanks
Dan
thats terrible. Get out of florida, its going to be under water completely in a few years. search the infamous naval map of the future united states. move to higher ground. My suggestion st george Utah,still sunny and warm but above sea level
I agree with Joanna, this article is misleading. I had the impression from reading the article that estrogen, specifically mentioned, would be removed by the berkey filters. I have owned a berkey for over a year now but the more I read and learn about water filtration the more I realise the berkey does not remove as many harmful contaminants as initially thought. Also, it's noteworthy that estrogen enters the water supply not only from women's urine and feces, as mentioned here, but also significantly from agriculture, industry and landfill waste.
Hi Kay -
To be clear, the berkey may remove estrogen and the probability is high given it removes similar compounds, however without testing we cannot state it removes it. The article is speaking to pharmaceuticals and hormones and then links to the testing for the removal of these. There are often lab limitations (at that point in time) that prevent the berkey to be tested for some specific chemicals or contaminants.
As for other harmful contaminants, the berkey has arguably been tested and shown to remove more contaminants most all other water filters on the market.
Thanks
Dan
Why not test for estradiol? Surely that is one of the most important contaminants - associated with male infertility etc......
The fact that it has not been tested suggests you cannot filter it out! Your article that mentions it as a serious contaminant -
and then carefully omits to say the Berkey has not been tested for this - is misleading, as it implies by omission that the Berkey is effective in this area.
Hi Joanna -
The lab did not have the ability to test for estradoil the time of testing. Until new lab testing is performed with the ability to test for this contaminant, we cannot make a statement as to it's effectiveness in this regard.
Thanks
Dan
Will Berkey be coming up with a filter to remove estradiols from our water? Or is there anything I can add onto my Berkey filter that would help eliminate this?
Hi Seema -
The berkey may already in fact remove estradiols, however it has just not been tested for that. We are unaware of it being on a future lab test.
Thanks
Dan
Perhaps you could perform your own test by introducing an estradiol into a sample of water...run it through...then have the filtered water tested??
Hi Bill -
All tests are done by independent certified labs. Our company is not certified to perform proper water testing, nor would it be independent, which consumers prefer to remove conflicts of interest.
Thanks
Dan