New study suggests PFAS exposure in Norway is underestimated
News
|Published
For the first time, trifluoroacetic acid (TFA) has been detected in blood samples from participants in a Norwegian study. TFA is one of many substances in the PFAS group found in the environment.
Trifluoroacetic acid (TFA) is a PFAS that has been little studied in humans. A recent study, conducted by researchers at the Norwegian Institute of Public Health (NIPH) and Örebro University in Sweden, measured both TFA and overall organic fluorine levels.
The study results show that a substantial share of overall PFAS exposure may be due to previously not identified PFAS substances.
Blood samples from Norwegian volunteers have been analysed for trifluoroacetic acid (TFA), other PFAS and the total amount of organic fluorine (TEF). TEF can indicate how much organically bound fluorine the samples contain in total.
What is PFAS, TFA and TEF?
PFAS
A large group of fluorinated chemicals that break down very slowly and can accumulate in the environment. They are therefore often referred to as “forever chemicals”.
TFA (trifluoroacetic acid)
A PFAS substance. It is short-chain and highly water-soluble, and it can also be formed when other fluorinated substances are degraded. Refrigerants, pesticides and medicines for animals and humans may possibly break down into TFA in the environment.
TEF (total extractable organic fluorine)
The total amount of organically bound fluorine in a sample. TEF higher than the sum of individually measured PFAS in a sample may indicate that other, unidentified fluorinated compounds are present in the samples.
Surprisingly high levels
The analyses were carried out to gain more knowledge about overall exposure to PFAS. TFA was detected in the blood samples, and the measured levels are higher than for other PFAS that are routinely analysed at the institute.
“This is the first time TFA has been investigated in Norwegian blood samples. Although it is not unexpected that TFA can be detected, it is surprising that TFA was the dominant PFAS in the samples. The findings emphasise the need to identify the sources of TFA exposure and assess possible health risks,” says Hubert Dirven, co-author of the study, and toxicologist at NIPH.
The TEF measurements were carried out to investigate whether the blood samples also contain fluorinated compounds that are not detected when only individual substances are measured. The results suggest that the identified PFAS, including TFA, account for only about half of the total amount of organic fluorinated compounds measured in the samples.
“This shows that there are significant knowledge gaps about the different types of PFAS in our bodies and their potential health impact. We therefore need to establish a more holistic picture of the total amount of PFAS we are exposed to, identify these unknown compounds, assess hazards and understand how we are exposed to them,” Dirven emphasised.
The analyses in this study were carried out at Örebro University as part of a project funded by the Nordic Council of Ministers. The project was undertaken jointly by NIPH and Örebro University.
The analysed samples come from the EuroMix study, a study conducted by NIPH in 2016 and 2017 with participants from the Oslo area. Previously, levels of 25 PFAS have been measured in blood samples from the participants (44 men and 100 women). Eight different PFAS were detected in all blood samples.
Calling for a ban on all PFAS in Europe
PFAS, or per- and polyfluoroalkyl substances as they are properly called, are very stable in the environment. Several PFAS are associated with adverse health effects, including effects on the immune system, impacts on the liver and possible cancer risk.
Norway and four other European countries have proposed a ban on all PFAS in Europe. This proposal is currently being considered within the EU.
For many years, the Norwegian Institute of Public Health has measured a range of PFAS in blood samples from the Norwegian population, and exposure to, among other substances, PFOA, PFOS, PFHxS and PFNA is widespread in Norway.