Black Berkey filter elements remove over 200 contaminants, including heavy metals, bacteria, viruses, pharmaceuticals, pesticides, and volatile organic compounds. Most contaminants are reduced by 99.8% or higher, and the filters meet the technical threshold for water purification (not just filtration) based on their pathogen removal rates.
Heavy Metals
Heavy metal removal is one of the strongest areas of Berkey’s performance. Lead, mercury, arsenic, and chromium VI are all reduced by more than 99.8%. Independent testing by Envirotek Laboratories showed the filters maintained 99.9% lead reduction through 160 gallons even when the incoming water contained lead at 67 times the EPA’s action level. The County of Los Angeles also ran lab tests on 19 inorganic contaminants and confirmed reductions up to 99.8%.
Other metals with 99.9% or higher reduction include copper, iron, zinc, manganese, nickel, selenium, antimony, and aluminum (99.1%). A few metals fall slightly lower: barium is reduced by more than 80%, cobalt by more than 95%, molybdenum by more than 90%, and vanadium by roughly 87.5%. These are still significant reductions, but worth noting if one of those specific metals is a concern in your water supply.
Bacteria, Viruses, and Parasites
To be classified as a water purifier rather than just a filter, a device must remove at least 99.9999% of pathogenic bacteria and 99.99% of viruses. The Black Berkey elements exceed both thresholds. They remove 99.9999999% of pathogenic bacteria and 99.999% of viruses.
The filters work mechanically, not chemically. Water passes through a dense maze of microscopic pores that physically trap bacteria, viruses, and cysts. This is an important distinction: the filtration doesn’t rely on adding any substance to the water to kill pathogens. It separates them out by forcing water through pores too small for microorganisms to pass through.
PFAS (Forever Chemicals)
The Environmental Working Group tested a Berkey system and found 100% elimination of the PFAS compounds measured. PFAS, often called “forever chemicals,” are synthetic compounds found in nonstick cookware, food packaging, and firefighting foam that have contaminated drinking water supplies across the country. They don’t break down naturally in the environment and have been linked to a range of health problems at even low concentrations. A 100% reduction rate puts Berkey among the top-performing filters for this category of contaminant.
Chlorine, Chloramines, and Disinfection Byproducts
Municipal water treatment plants add chlorine or chloramines to kill bacteria, but these chemicals affect the taste and smell of tap water and can form byproducts that carry their own health risks. Black Berkey elements reduce free chlorine and chloramines by more than 99.9%. Haloacetic acids, a common group of disinfection byproducts, are reduced by more than 98%.
Pharmaceuticals and Hormones
Trace amounts of medications end up in water supplies through human waste, agricultural runoff, and improper disposal. The filters reduce 17 pharmaceutical compounds by more than 99.5% each. These include common pain relievers like acetaminophen, ibuprofen, and naproxen, as well as antibiotics, anti-seizure medications, cholesterol drugs, and the hormone progesterone.
Bisphenol A (BPA) and triclosan, two industrial chemicals frequently found in plastics and personal care products, are also reduced by more than 99.5%.
Volatile Organic Compounds
VOCs are carbon-based chemicals that evaporate easily and often enter water through industrial discharge, gasoline spills, or agricultural chemicals. The filters reduce most VOCs by 99.8% or higher. This includes benzene, toluene, chloroform, and trichloroethylene (TCE), all common groundwater pollutants. MTBE, a gasoline additive that has contaminated wells across the U.S., is reduced by more than 99.6%.
Petroleum contaminants like gasoline, diesel, crude oil, and kerosene are all reduced by more than 99.9%.
Fluoride Requires a Separate Filter
The standard Black Berkey elements do list fluoride reduction at 99.9%, but for targeted fluoride and arsenic removal, Berkey sells a separate add-on called the PF-2. These secondary filters attach to the bottom of the primary filter elements and hang in the lower chamber of the system. You need one PF-2 for each Black Berkey element you’re running.
Under standard conditions, the PF-2 filters reduce fluoride by more than 95%. Under optimal conditions (particularly when your water’s pH falls between 5.0 and 7.0), that number climbs above 99.75%, bringing the fluoride concentration below 50 parts per billion. The tradeoff is a 15 to 20% slower flow rate, and the PF-2 filters need replacing every 1,000 gallons or once a year, whichever comes first.
What the Filters Don’t Remove
Berkey filters are designed to leave beneficial minerals in the water. Calcium, magnesium, and potassium pass through largely intact, which is why filtered water still has a natural mineral taste rather than tasting flat like distilled water. The system also does not soften water or remove total dissolved solids (TDS), so if you test your water with a TDS meter before and after filtering, the number won’t drop dramatically. That’s by design, not a flaw.
Filter Lifespan
A pair of Black Berkey elements is rated for approximately 3,000 gallons. For a household using about 2 gallons per day, that translates to roughly 4 years of use before replacement. The PF-2 fluoride filters have a much shorter life at around 1,000 gallons per pair, or about one year at the same usage rate. The Environmental Working Group’s review noted that filter life can stretch beyond 8 years at low daily usage, making the long-term cost relatively low despite the higher upfront price.
The EPA Classification Dispute
In 2022, the EPA ordered Berkey to stop selling its filters, classifying them as unregistered pesticides. The dispute centers on the silver embedded in the filter elements. Berkey uses silver to protect the filter material itself from bacterial growth, not to kill pathogens in the water passing through. The company argues the silver serves the same purpose as antimicrobial coatings on other consumer products and that the filters work through mechanical separation, trapping contaminants in micropores rather than using any chemical to treat the water.
Berkey filed a lawsuit challenging the EPA’s classification, pointing out that the company sold its filters without regulatory issue for 25 years before the stop-sale order. The legal dispute has affected product availability in the U.S., so depending on when you’re reading this, purchasing options may be limited or may have shifted to newer product lines under different branding.