# Is a PFAS blood test worth it? Source page: https://intrinsicprism.com/learn/is-a-pfas-blood-test-worth-it Updated November 2026 · Last reviewed: November 2, 2026 It can be, if you want to know how much of certain PFAS are in your blood and will discuss the result with a clinician. ATSDR says a result will not give clear information about health effects, pinpoint a health problem or guide treatment.[[1]](#source-1) Check your drinking water first; it is often the easier question to answer.[[2]](#source-2) ## PFAS in blood: key numbers - Nearly all people in the U.S. have PFAS in their blood, according to ATSDR. CDC's National Health and Nutrition Examination Survey (NHANES) has measured blood PFAS in the U.S. population since 1999.[[7]](#source-7) - Some levels are falling: from 1999-2000 to 2018-2019, blood PFOS levels declined by more than 85% and blood PFOA levels by more than 70% as production and use declined. ATSDR notes people may be exposed to other PFAS as PFOS and PFOA are phased out and replaced.[[7]](#source-7) - The National Academies of Sciences, Engineering, and Medicine (NASEM) guides clinicians using the sum of seven PFAS in serum or plasma: adverse health effects are not expected at less than 2 ng/mL, there is a potential for adverse effects between 2 and 20 ng/mL, especially in sensitive populations, and an increased risk above 20 ng/mL. Using NHANES data, the committee estimated that 2 ng/mL corresponds to the 2nd percentile and 20 ng/mL to the 91st percentile, placing 89 percent of the U.S. population between the two cutoffs and 9 percent above 20 ng/mL. It notes that the relevance of these values to interpret risk in individuals is uncertain.[[8]](#source-8) ## Who might find a PFAS blood test useful? - People who want to document their PFAS exposure, for example after learning about PFAS in their drinking water.[[1]](#source-1) - People who want a baseline before and after changing a known source, such as their water supply. - People working with a clinician who wants exposure data alongside a history and examination.[[1]](#source-1) ## What can't a PFAS blood test tell you? - Whether PFAS caused a health problem: ATSDR says results will not pinpoint a health problem or give clear information about health effects.[[1]](#source-1) - How to treat you: ATSDR says results will not guide treatment.[[1]](#source-1) - Your future risk: ATSDR says results will not predict or rule out future health problems.[[1]](#source-1) - Where the PFAS came from: a blood level does not name the source. A PFAS blood test is not routinely done in a doctor’s office.[[2]](#source-2) ## Why check your water first? ATSDR suggests asking your local health department about PFAS in your water.[[2]](#source-2) Our free [PFAS tap water ZIP code lookup](https://intrinsicprism.com/tools/pfas-water-lookup) shows EPA results for the public water systems listed for a ZIP code; it is per system, not per home. ## How to decide - **A blood test may be worth it if** you want a number for your own exposure and will act on it with a clinician, for example by tracking a change in water source.[[1]](#source-1) - **It may not be worth it if** you expect it to explain symptoms or tell you what to do medically; ATSDR says it cannot.[[1]](#source-1) - **Cost:** compare what each option measures and what is included. See [how much a PFAS test costs](https://intrinsicprism.com/learn/pfas-test-cost). ## Where does Intrinsic Prism fit? Intrinsic Prism is an at-home testing and guidance package covering 133+ markers across mycotoxins, heavy metals, environmental toxins, PFAS chemicals and toxin genetics.[[3]](#source-3) PFAS are measured in a blood or serum sample.[[5]](#source-5) The package is $1,999 per participant and HSA/FSA eligible; your plan administrator decides reimbursement.[[4]](#source-4) We ship to most countries; availability is confirmed at checkout.[[6]](#source-6) Results are educational and are not a diagnosis. See what our [PFAS blood test](https://intrinsicprism.com/tests/pfas-blood-test) measures. ## Related guides - [PFAS test at home](https://intrinsicprism.com/learn/pfas-test-at-home) - [How much does a PFAS test cost?](https://intrinsicprism.com/learn/pfas-test-cost) - [PFAS blood test at home](https://intrinsicprism.com/tests/pfas-blood-test) - [PFAS statistics](https://intrinsicprism.com/learn/pfas-statistics) - [PFAS drinking water limits](https://intrinsicprism.com/learn/limits/pfas-drinking-water-limits) ## Frequently asked questions Is a PFAS blood test worth it? : It can be if you want to document your exposure and will discuss the result with a clinician. It will not give clear information about health effects or guide treatment.[[1]](#source-1) Can a PFAS blood test diagnose a disease? : No. ATSDR says results will not pinpoint a health problem.[[1]](#source-1) Should I test my water or my blood first? : Water is often the easier first step: ATSDR suggests asking your local health department about PFAS in your water.[[2]](#source-2) Our [tap water lookup](https://intrinsicprism.com/tools/pfas-water-lookup) shows public water system results. Can my regular doctor order a PFAS blood test? : ATSDR notes that a PFAS blood test is not routinely done in a doctor’s office.[[2]](#source-2) How much does a PFAS blood test cost with Intrinsic Prism? : $1,999 per participant, one-time, for one test covering 133+ markers including the PFAS panel. It is HSA/FSA eligible; your plan administrator decides reimbursement.[[4]](#source-4) How common is PFAS in people's blood? : Very common. ATSDR says nearly all people in the U.S. have PFAS in their blood, based on CDC's NHANES survey.[[7]](#source-7) What PFAS blood level is considered high? : NASEM uses the sum of seven PFAS in serum or plasma: adverse effects are not expected below 2 ng/mL, there is a potential for adverse effects between 2 and 20 ng/mL, and an increased risk above 20 ng/mL. It notes these cutoffs come from population studies and their relevance to an individual is uncertain.[[8]](#source-8) Are PFAS blood levels going down? : For some PFAS, yes. ATSDR reports that from 1999-2000 to 2018-2019 blood PFOS levels declined by more than 85% and blood PFOA levels by more than 70%; people may be exposed to other PFAS as these are replaced.[[7]](#source-7) ## Sources and dates Last updated: November 2, 2026. Last reviewed: November 2, 2026. Prepared by the Intrinsic Prism team. Intrinsic Prism statements come from its live site on November 2, 2026. This page is educational information, not medical advice. 1. [[1] Testing for PFAS | PFAS and Your Health | ATSDR](https://www.atsdr.cdc.gov/pfas/blood-testing/index.html) Fetched and checked 2026-10-28. 2. [[2] Perfluoroalkyls ToxFAQs | ATSDR](https://wwwn.cdc.gov/TSP/ToxFAQs/ToxFAQsDetails.aspx?faqid=1116&toxid=237) Fetched and checked 2026-10-28. 3. [[3] What we Test | Intrinsic Prism (marker directory)](https://intrinsicprism.com/what-we-test) Read from the live site 2026-10-28. 4. [[4] Order the test | Intrinsic Prism (price, marker groups, HSA/FSA)](https://intrinsicprism.com/buy) Read from the live site 2026-10-28. 5. [[5] FAQ | Intrinsic Prism](https://intrinsicprism.com/faq) Read from the live site 2026-10-28. 6. [[6] Shipping and delivery | Intrinsic Prism](https://intrinsicprism.com/shipping) Read from the live site 2026-10-28. 7. [[7] Fast Facts: PFAS in the U.S. Population | PFAS and Your Health | ATSDR](https://www.atsdr.cdc.gov/pfas/data-research/facts-stats/index.html) Fetched and checked 2026-11-02. 8. [[8] National Academies of Sciences, Engineering, and Medicine (2022). Guidance on PFAS Exposure, Testing, and Clinical Follow-Up, Chapter 5](https://www.nationalacademies.org/read/26156/chapter/7) Fetched and checked 2026-11-02.