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PFAS in drinking water questions answered

Your PFAS Water Test Questions Answered

Pervasive, persistent, and toxic…per- and polyfluoroalkyl substances (PFAS) are a group of nearly 5,000 synthetic chemicals present in a range of products including stain resistant textiles, military-grade firefighting foam, and food packaging. Scientists are still learning about the impact of PFAS on human health, but certain PFAS are proven to disrupt hormone function, cause developmental issues in infants, increase your risk of cancer, and several other concerning health effects. 

PFAS have been present in consumer goods for over 70 years, though PFAS exposures through food and drinking water only became a topic of research 20 years ago. Thus, methods for analyzing PFAS in drinking water are still being developed and just a handful of multi-laboratory validated testing methods currently exist. 

In this Tips for Taps article, we will answer the most common questions our customers ask us about PFAS testing. 

Want to learn more about PFAS? Check out these articles for more information:

  • PFOA, PFOS, and PFAS: What You Need to Know 
  • What We Know About PFAS and Your Health
  • Is My Non-Stick Pan Toxic? An Expert Perspective
    • What PFAS Testing Methods Does SimpleLab Use? 

      Different testing methods are developed for different testing media (e.g. drinking water, wastewater, soil, and blood serum). In this article, we’ll only discuss drinking water testing methods. To test your water for PFAS, you can purchase a PFAS add-on in addition to any of our Essential, Advanced, or Extended water tests here.

      SimpleLab’s network of certified labs uses Environmental Protection Agency (EPA) Method 537.1 for our PFAS Water Test and EPA Method 533 for our GenX and PFAS Water Test. These methods are two of just three methods used to test for PFAS in drinking water that were developed, validated, and published by the EPA’s team of expert scientists. 
      Published in 2018, EPA Method 537 tests for up to 18 different types of PFAS, including some of the more well-known species like PFOA and PFOS. SimpleLab’s PFAS Water Test offers 14 of the 18 PFAS because fewer analytes drastically reduces the price for customers. EPA Method 533 (published in 2019) and tests for 25 different PFAS, all offered in SimpleLab’s GenX and PFAS Water Test.

      Our labs can detect PFAS as low as 2 parts per trillion (PPT), which is 35 times lower than the EPA’s current health advisory level (70 PPT).

      All EPA-verified methods test for a set of specific PFAS, which often underestimates total PFAS contamination. There exists a few research methods that test for the total sum of PFAS, such as Total Organic Fluorine (TOF) and Total Oxidizable Precursors (TOP). These methods lack specificity about which compounds are present, rather aiming to represent total fluorine exposures (TOF) and precursors to PFAS with TOP. Neither method is commercially available for drinking water samples, but hold promise as an advance on current targeted methods. The EPA is currently developing methods and exploring the possibility of conducting multi-laboratory validation for the TOP method.

      Why Aren’t PFAS Included in Tap Score’s Essential, Advanced, or Extended Water Tests?

      Awareness about PFAS is quite new. 

      While you might recognize PFAS from the news or emerging scientific literature—there are even several films about them (Dark Waters and The Devil We Know)—the general public only became aware of PFAS as a public health problem recently. Fewer customers are testing for PFAS compared to common water contaminants like lead, arsenic, and nitrate.

      Including PFAS in every baseline test becomes cost prohibitive for most folks. 

      SimpleLab’s core test packages are aimed to maximize affordability of testing a large set of contaminants. Customers wishing to test for PFAS can include this test as a specialized add-on.

      PFAS have specific testing needs

      PFAS need specific preservation and sampling containers. This is because PFAS compounds may be present in other types of vials and artificially inflate the estimated amount of PFAS in your water! Unique testing materials also increase the cost of PFAS testing.

      How Is the Cost of the PFAS Water Test Determined?

      Simple economics. 

      Labs prefer to handle larger orders rather than single orders because larger ones reduce their cost-per-order. With fewer people testing for PFAS the costs do not yet reflect economies of scale that may drive down prices.

      Newly developed methods cost more. 

      Well-known water contaminants such as lead and arsenic have been known to be harmful for well over 100 years. However, PFAS were only confirmed to be toxic in the last 20 years. Thus, scientists have had an 100-year advantage to develop cost-effective testing methods for traditional water contaminants.

      Why Do SimpleLab’s PFAS Results Take Longer Than Other Contaminant Results?

      The instruments used for PFAS analysis are highly sophisticated. 

      The machine used for PFAS testing is called Liquid Chromatography with tandem Mass Spectroscopy (LC-MS/MS for short). The LC-MS/MS is much more specific and sensitive compared with other machines used for analyzing drinking water samples. 

      PFAS are evaluated at extremely low concentrations.

       The EPA health advisory for PFAS (70 PPT) is more than 100 times lower than maximum contaminant levels for common water contaminants like arsenic and nitrate (10000 PPT and 10000000 PPT, respectively). Therefore, PFAS testing demands a high level of analytical sensitivity to ensure an accurate and precise analysis of these low (but toxic) concentrations.

      How Do SimpleLab’s PFAS Methods Compare?

      In the table below, we compared the methods SimpleLab uses (EPA Method 537.1 and EPA Method 533) with current multi-laboratory validated PFAS testing methods. It is important to note that long-chain PFAS (PFAS with 6 or more carbons) are generally considered more persistent in the human body than short-chain PFAS (PFAS with 5 or fewer carbons).

      PFAS Testing by Method

      Test for PFAS at the Tap

      When it comes to getting your water tested, we understand that you want to make an informed decision so that you can ensure the most reliable results. So hopefully we’ve covered all you need to know about PFAS testing.

      Explore SimpleLab’s PFAS tests:



      Why Trust Tap Score?

      We know how confusing it can be to find advice on water quality and treatment you can trust. That’s part of the reason we made Tap Score—to help improve the way you test and treat your drinking water.

      • No affiliate links: Unlike most sites revolving around water quality, we do not take a cut from sales on filtration systems.
      • Unbiased advice: Our blog is independently researched by our team of water scientists and designed to provide clarity on water quality, not to sell treatment products.
      • Independent laboratory testing: Tap Score test results come from SimpleLab's third-party network of certified laboratories; in other words, accredited labs provide the data without conflicts of interest.
      • Continuously updated: Science never rests. That’s why our content always reflects the latest developments in scientific research and regulatory standards.
      • Always available: Our customer service team is the best in the industry and available anytime via chat to answer all your water quality questions.



      Sources and References

      Basic Information on PFAS | Per- and Polyfluoroalkyl Substances (PFAS)

      Per and Polyfluoroalkyl Substances (PFAS) 

      PFAS Contamination of Water: Department of Health

      Human exposure to per- and polyfluoroalkyl substances (PFAS) through drinking water: A review of the recent scientific literature 

      Tips for Taps | SimpleLab

      PFOA, PFOS, and PFAS: What You Need to Know 

      What We Know About PFAS and Your Health

      Is My Non-Stick Pan Toxic? An Expert Perspective

      Collections | SimpleLab 

      How To Interpret Water Testing Units | SimpleLab Tap Score

      Measuring total PFASs in water: The tradeoff between selectivity and inclusivity 

      Determination of Total Organic Fluorine (TOF) in environmental samples using flow-injection and chromatographic methods 

      PFAS Total Oxidisable Precursor Assay (TOP Assay) - Eurofins Scientific

      PFAS Analytical Methods Development and Sampling Research | US EPA 

      Dark Waters Movie | Official Website | Trailers and Release Dates 

      The Devil We Know 

      LC-MS/MS in the Clinical Laboratory – Where to From Here? 

      Serum Half-Lives for Short- and Long-Chain Perfluoroalkyl Acids after Ceasing Exposure from Drinking Water Contaminated by Firefighting Foam 

      Oxidative Conversion as a Means of Detecting Precursors to Perfluoroalkyl Acids in Urban Runoff 

      11 Sampling and Analytical Methods – PFAS — Per- and Polyfluoroalkyl Substances

      Implication of PFAS Precursors at AFFF-Impacted Sites  

      ISO 25101:2009  Determination of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) 

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