PFAS compounds are linked with a wide range of serious health effects. People are being encouraged to get tested for PFAS. But what then? How do you know if your results are a cause for concern? And what can you do if you actually have high PFAS?
What is PFAS
PFAS is a catch-all term for a large family of artificial chemicals that have been widely used since the 1960s. PFAS are popular with manufacturers because they have some unique properties. These include:
- Nonstick
- Water repellant
- Greaseproof
- Heat resistant
- Low friction
The problem is, PFAS compounds are very hard to break down in the environment and the body. This has led to them being called “forever chemicals.”
Health effects
There is growing evidence that PFAS has some very serious health effects. This includes links with:
- Several forms of cancer
- High cholesterol (dyslipidemia) and cardiovascular disease
- Inflammatory conditions like ulcerative colitis
- Reduced immune responses (immunosuppression)
- Premature birth and slower fetal development
However, there are many other health concerns.
Monitoring your PFAS levels
Anyone can get tested for PFAS in your blood. These tests fall into two broad categories:
- Whole blood tests, which check the level of PFAS in a sample of your blood
- Serum blood tests, which check the levels in serum, which is the liquid part of the blood with the proteins removed
Whole blood tests can be administered using a home test kit or via a blood draw in a clinic. By contrast, serum tests can only be done using a blood draw. Both techniques can deliver highly accurate results, but clearly it is less convenient to have to go somewhere to have a blood draw.
Understanding your PFAS results
Both types of PFAS test will give you results for a variety of different compounds. The exact number varies depending on the test. But almost all tests look at a core set of compounds sometimes referred to as NHANES compounds.
What is NHANES?
NHANES is a long-term biomonitoring program run by the CDC. It has been testing thousands of people for PFAS compounds since around 2000. They test a core set of around 9 compounds (although for some of these they separate them into sub-types). This data is publicly available, which means you can compare your own results with the broader US population.
Interpreting your results
Both serum and whole blood PFAS tests give you results in nanograms per milliliter (ng/mL). However, you can’t directly compare the results. As a rule of thumb, you need to double the whole blood level to get the serum blood level. NHANES results are based on serum testing, so you need to bear this in mind when interpreting your results.
The level of any specific PFAS compound doesn’t necessarily tell you anything about your overall risk. PFOA (perfluorooctane sulfonic acid) is defined as a carcinogen by the WHO. But there is clear evidence that many related compounds are also carcinogenic. The guidance from the National Academies of Science, Engineering, and Medicine is to add up the total PFAS levels for a specific group of PFAS compounds that are included in the NHANES list. You then see whether this total level (which we call the NASEM level) exceeds a given threshold.
NASEM levels in more detail
NASEM defines three levels for PFAS exposure. These are explained below.
Low (under 2 ng/mL). This is likely a completely safe level of PFAS. However, NHANES data suggests that under 20% of the US population is below this threshold.
Medium (between 2 and 20 ng/mL). Here there is an increased risk, and certain additional testing is recommended. This includes getting tested for cholesterol, breast cancer, and (if relevant) preeclampsia.
High (above 20 ng/mL). This is viewed as a concerning level of PFAS for anyone. NASEM advises physicians to send anyone with this level for additional screening tests for thyroid function, kidney and testicular cancer, and ulcerative colitis. Around 10% of the population fall into this category.
Actions you can take to reduce PFAS
If you have high PFAS levels you should definitely consult your physician and share the NASEM guidelines with them. There are also concrete steps you can take to help reduce your levels.
- Fit PFAS-reducing water filters and keep these well maintained
- Replace any non-stick cookware with PFAS-free alternatives
- Avoid the use of PFAS-containing clothing (typically clothes advertised as “breathable waterproofs” contain a layer of PFAS)
- Reduce the amount of take out food you consume, or change to establishments that provide reusable containers
You should also get tested periodically so that you can monitor your PFAS levels over time.
