How background contamination disrupts PFAS research

Perfluoroalkyl and polyfluoroalkyl, also known as PFAS or ‘forever chemicals’, are among today’s most pressing pollution concerns. They’re found in everything from food to children’s toys. Careful lab testing is vital for detecting PFAS and minimising exposure, but background contamination can disrupt testing efforts. What causes background contamination? How can lab personnel prevent contamination and protect their PFAS research processes?

Sample contamination challenges in PFAS research

PFAS research is vital for eliminating forever chemicals in food, water, clothing and countless other items. More and more organisations are prioritising PFAS research, especially since the EPA announced new regulations in 2023. Sample contamination poses a threat to this critical research. Undetected or unresolved contamination can compromise the results of measurements and experiments. It can also pose health risks to lab employees.
Also known as ‘background noise’, contamination has the potential to derail PFAS research by creating confusing or skewed results. For instance, a sample might arrive at the lab undamaged and then experience contamination from a piece of lab equipment that contained PFAS.
Lab employees need to be made aware of sources of contamination within the lab to arrive at accurate conclusions that disrupt research. For example, a lab employee might mistakenly determine that a water source is contaminated with PFAS when, in reality, the PFAS chemical entered the sample after arriving at the lab.

How do samples get contaminated?

Where does PFAS contamination come from? Minimising exposure is crucial to preventing contamination, but it can be difficult to trace. There are two components to minimising contamination: understanding its sources and implementing strategies to protect samples.
PFAS contamination can occur during three general stages of the sample delivery process. First, it can come from the sample’s original source. This is the only type of PFAS contamination that should make it to the lab because it shows a genuine presence of PFAS.
Next, samples can experience exposure to contaminants during transportation between the sampling site and the lab. This is the most challenging contamination type since lab personnel have low visibility of the transportation process.
Finally, contamination can occur within the lab. This may be surprising since lab personnel typically go to great lengths to prevent contamination. However, everything from lab equipment to tap water can contain PFAS.
For example, sample containers themselves can contain traces of PFAS. EPA guidelines recommend sticking to polypropylene, LDPE or polyethylene collection materials to avoid contamination. It may not be enough to eliminate the risk of PFAS exposure, though. Since these forever chemicals have become so omnipresent in modern manufacturing, they could be on virtually any surface or object in the lab.

Strategies to prevent sample contamination

What can lab personnel do to minimise the risk of background contamination in PFAS research? The most effective approach is preventative measures to protect samples from collection to processing at the lab.
First, as mentioned above, lab personnel should ensure collection teams are always using PFAS-free Petri dishes and containers. Sterilise each container before placing a sample inside. Collection teams should also be careful to wear PFAS-free gloves and protective equipment when handling samples. It may be a good idea to double package or double seal each sample before transportation.
The transportation process is often the most challenging to control, but a few precautions can help. For example, minimise the number of people who touch any of the samples as much as possible. Have collection personnel carefully package groups of samples in sealed containers. If possible, arrange for non-stop transportation on a single vehicle so the samples don’t have to change hands part-way to their destination.
All contact with samples should be carefully monitored once samples arrive at the lab. Get started by using EPA-recommended PFAS testing methods to determine initial PFAS levels in each sample. If higher levels of PFAS appear after later tests, lab personnel can compare the data to the initial tests to determine where contamination may have occurred.
Lab managers should also verify that all of their equipment, particularly gloves and test surfaces, is PFAS-free. Look for anything made with fluoropolymers. These polymers are among the most likely sources of PFAS contamination in labs due to their high resistance to solvents and acids. It is also wise to test all water sources in the lab for PFAS, although standard sterile water should be safe.
Finally, labs can significantly reduce the likelihood of contamination by automating most or all testing processes. Automation helps to minimise the number of people who touch the samples, which also reduces the risk of human error. Additionally, it ensures testing processes are standardised and consistent as well. Testing standardisation is beneficial for ensuring compliance with the growing number of regulations surrounding PFAS chemicals.
Utilising these preventative measures can go a long way toward eliminating background contamination. Plus, automation can lead to more efficient, cost-effective testing.

Protecting PFAS research from background contamination

Accurate, efficient PFAS research is critical to addressing the severe global health risk posed by ‘forever chemicals’. Unfortunately, background contamination can derail research efforts by creating inaccurate, misleading or skewed test results. Labs can eliminate the risk of contamination using several preventative measures. These strategies include using PFAS-free collection equipment, minimising contact with samples and ensuring labs are free of materials containing PFAS chemicals.