Researchers at the German Center for Neurodegenerative Diseases (DZNE) have shown that traces of the ubiquitous PFAS chemicals in human blood are associated with unfavorable lipid profiles and therefore with an increased risk of cardiovascular disease.
Researchers at the German Center for Neurodegenerative Diseases (DZNE - Deutsches Zentrum für Neurodegenerative Erkrankungen) have shown that traces of the ubiquitous PFAS chemicals in human blood are associated with unfavorable lipid profiles and therefore with an increased risk of cardiovascular disease.
Since their invention in the 1950s, it is estimated that more than 10,000 different substances from the category of per- and polyfluorinated alkyl compounds (PFAS) - i.e. 'P-barrel' - have been developed. Due to their water-, grease- and dirt-repellent properties, they are used in thousands of products such as cosmetics, dental floss, pan coatings and fire-fighting foam, and are also ubiquitous in electronics technology. In addition to their basic chemical structure, PFAS have another thing in common: they are virtually non-degradable - hence their designation as 'eternity chemicals'. They enter the human food chain via groundwater in particular. There is also evidence that they accumulate in the liver and can damage it. PFAS increase the risk of cancer, they can trigger thyroid problems and a reduced immune response to vaccinations.
The findings of the study published in February 2024 are based on data from more than 2,500 adults from Bonn and the Dutch municipality of Leiderdorp. PFAS were detectable in the blood of almost all study participants. The study results have been published in the renowned scientific journal 'Exposure and Health' under the open access license CC BY 4.0[1].
|
PFAS |
Study |
Model † |
LDL-C |
HDL-C | ||||
| β [95 % CI] |
p-value |
β [95 % CI] |
p-value | |||||
| PFOA |
NEO |
Insges. |
0.019 [ 0.001; 0.036] |
0.0413 | 0.016 [ 0.004; 0.029] |
0.0112 | ||
| Rhineland study |
Total |
0.005 [-0.006; 0.016] |
0.388 | 0.007 [-0.001; 0.016] |
0.0690 | |||
| PFOS |
NEO |
Insges. |
0.023 [0.004; 0.041] |
0,0153 | 0.007 [-0.006; 0.021] |
0.2675 | ||
| Rhineland study |
Total |
0.007 [-0.003; 0.017] |
0.1726 | 0.005 [-0.002; 0.013] |
0.1575 | |||
| PFHxS |
Rhineland study |
Insges. |
0.013 [0.003; 0.023] |
0.0128 | 0.012 [0.004; 0.019] |
0.0024 | ||
The debate about PFAS continues
The study will contribute to the current social debate on restricting or even banningPFAS. The ideas of health and environmental representatives on the one hand and the industry on the other are still far apart. This is also due to the fact that the dangers to our health are becoming ever more apparent, but so far only limited alternatives are available in the PFAS-using industry. Environmental representatives want to restrict the use of PFAS at EU level. A restriction proposal has been submitted to the European Chemicals Agency (ECHA) for some time[2] and if adopted could ban the use of these chemicals in the long term.
Representatives from the scientific community point out that the fluorochemical industry is already increasingly focusing on fluorinated gases and fluoropolymers and no longer wants to retain other uses of PFAS. Further development will also depend on how quickly, for example, fluorine-free substances for important components in electrical and electronic devices for the energy transition - such as fuel cells, batteries or semiconductors - become available. Representatives of the Federation of German Industries (BDI), however, warn against too tight a restriction, as no satisfactory alternatives will be available for many PFAS applications in the foreseeable future. This applies to the manufacture of wind turbines, photovoltaic panels and semiconductors, among other things. In the manufacture of semiconductors, PFAS can be found in almost all sub-processes, e.g. in etching, photolithography, rinsing or in the production of single-crystal semiconductor rods.
The industry is therefore demanding exemptions from the ban for socially important applications. These assessments, which are only mentioned as examples, show how contradictory the views of the players involved are. In this article, PLUS presents the results of the above-mentioned research work on the effects of PFAS on human health as a topical part of the debate.
|
Total cholesterol |
Triglycerides |
||
| β [95 % CI] | p-value | β [95 % CI] | p-value |
| 0.020 [ 0.007; 0.034] |
0.0025 |
0.013 [-0.010; 0.036] |
0.2787 |
| 0.008 [-0.001; 0.016] |
0.0665 |
-0.001 [-0.015; 0.014] |
0.9362 |
| 0.020 [ 0.007; 0.034] |
0.0037 |
0.016 [-0.009; 0.040] |
0.2031 |
| 0.007 [-0.001; 0.014] |
0.0837 |
-0.005 [-0.018; 0.008] |
0.4502 |
| 0.012 [0.004; 0.020] |
0.0023 |
-0.006 [-0.019; 0.007] |
0.3969 |
Younger people particularly affected
The researchers see clear signs of a harmful effect of PFAS on health. In the studies, they found that the negative effects are more pronounced in younger test subjects than in older ones, even though the PFAS concentration in the blood is the same.
The results of the current study also suggested that even relatively low PFAS concentrations in the blood are associated with unfavorable blood lipid profiles. The data show a statistically significant correlation between PFAS in the blood and harmful blood lipids associated with cardiovascular risk. The higher the PFAS level, the higher the concentration of these lipids. According to the research team, this is not strictly speaking proof that the PFAS chemicals are the cause of the unfavorable blood lipid profiles. However, the close correlation supports this suspicion. It is a strong argument for stricter regulation of PFAS in order to protect health. It is also striking that PFAS could be detected in the blood of almost all test subjects. It is therefore impossible to avoid these chemicals. The researchers are convinced that in the long term, the increased risk does have a negative effect on the heart and circulation.
Blood samples from Bonn and Leiderdorp
The basis for the current study was the so-called 'Rhineland Study' of the DZNE - a population-based health study in the Bonn city area - and the so-called NEO study from the Netherlands (Netherlands Epidemiology of Obesity study). The DZNE research teamcollaboratedwith experts from LeidenUniversity Medical Centerin the Netherlands. Blood samples from a total of more than 2,500 women and men aged between 30 and 89 were included in the analyses. State-of-the-art technology was used. For a few years now, technology has been available to analyze blood samples with the accuracy required to answer the questions posed by the study.
Most detailed study to date
The blood samples were analyzed in detail using mass spectrometry. In their analysis, the researchers focused on three of the most widespread PFAS types - PFOA, PFOS and PFHxS - and also determined the concentration of 224 blood lipids, metabolites (substances that are formed as intermediates or degradation products of metabolic processes in the organism) and amino acids.
The PFAS were measured with the Metabolon HD4 platform, lipoprotein and metabolite profiles with Nightingale nuclear magnetic resonance spectroscopy. Using this deliberately broad approach without a preconceived objective, the researchers were able to demonstrate the link between PFAS concentration and a detrimental profile of lipids. These include the well-known cholesterol and various other blood lipids that are known to be risk factors for cardiovascular disease. There were no significant differences between the samples from Bonn and Leiderdorp. The researchers are convinced that this study is the most detailed on this topic to date and the one with the largest database. Previous studies had already suggested a correlation between PFAS and unhealthy blood lipids, but this connection had never been as clear as in this study.
Outlook and conclusions
According to the Bonn research team, future studies could focus on specific areas of the body. After examining the blood count, the next step would be to investigate the occurrence of PFAS in individual organs, for example. In their study, the researchers point out, citing various sources, that environmental pollution with PFAS is widespread in both Germany and the Netherlands. In Germany, areas along the Rhine are considered to be heavily contaminated. In particular, PFAS levels are detectable in the groundwater of most federal states and in soil samples from all federal states. For this reason and based on the results of the study, the researchers suggest that stricter regulations may be necessary for all PFAS substances. In addition, due to the persistence of PFAS in the environment, there would be a need to actively remove these chemicals from the environment.
References
[1] Faquih, T.O., Landstra, E.N., van Hylckama Vlieg, A. et al. Per- and Polyfluoroalkyl Substances Concentrations are Associated with an Unfavorable Cardio-Metabolic Risk Profile: Findings from Two Population-Based Cohort Studies, Expo Health (2024), https://doi.org/10.1007/s12403-023-00622-4 (accessed: 03.09.2024).
[2] www.echa.europa.eu/de/hot-topics/perfluoroalkyl-chemicals-pfas (accessed: 03.09.2024).
