I PFAS I am perfluoroalkyl substances, i.e. resistant, fire-retardant and water-repellent chemical compounds, used to make many commonly used materials resistant to water and grease. We are talking about coatings for food containers, fabrics, paper, carpets, pesticides, building materials and cleaning and personal hygiene products.
The two most used chemical compounds belonging to this group are perfluorooctanoic acid (PFOA) and perfluorooctansulphonic acid (PFOS) but the Organization for Economic Co-operation and Development (OECD) includes well within this category 4,730 different moleculesmaking this group the largest family of emerging pollutants.
PFAS: how do they enter the environment?
Due to their high molecular stability, these compounds end up spreading in large quantities in the environment, where they can remain for years. PFAS can be found anywhere: in the air, in the soil but also in the water. In fact, they mainly flow into water basins, from where they can travel great distances and enter the aquatic ecosystem, reaching man. Traces of PFAS have been found in breast milk, placenta, seminal fluid and hair.
We generally get in touch with the PFAS through the consumption of drinking water and food. Other possible exposures of the human organism are through inhalation of contaminated air, ingestion or contact with contaminated dust or soil. Workers in plants that produce or use perfluoroalkyls may be exposed to higher levels than the general population.
The Italian study on the toxicity of PFAS in humans
The data present in the literature have highlighted the toxicity of PFAS on humans but up to now an overall analysis of all the studies conducted on the subject had not yet been carried out. Instead, researchers from the University of Bologna and the University of Padua thought about it, comparing the different works, publishing the results in a comparative transcriptional analysis in the journal Toxics.
The researchers collected 2,144 samples from seven different animal species to examine responses at the molecular level of PFAS exposure. “Our goal was to highlight the molecular effects induced by PFASs not only at the level of single genes but also on various molecular pathways and cell types. And we were able to demonstrate for the first time that the effects of exposure to these compounds are conserved at the molecular level and produce consequences both in humans and in other animal species”, intervenes Frederick Manuel Giorgiprofessor at the Department of Pharmacy and Biotechnology of the University of Bologna.
All negative health effects
The data from the Italian research confirm the negative effects on health. Exposure to PFAS, for example, involves a regression of metabolism and lipid transport and other processes related to ovarian development, estrogen production, ovulation, and physiological functioning of the female reproductive system. It is assumed, therefore, that the PFAS are harmful to fertility and fetal development.
Scholars have also highlighted that exposure to perfluoroalkyl substances produces a upregulation of the ID1 geneinvolved in the development of various types of tumors, including leukemia, breast cancer e al pancreas. Furthermore, the data shows that individuals affected by malignant neoplasms of lymphatic and hematopoietic tissues, such as the spleen, liver and bone marrow, are more likely to suffer fatal outcomes if continuously exposed to these compounds.
The study by the Universities of Bologna and Padua, then, confirmed the toxicity of PFAS on the immune system. The researchers have in fact highlighted the mechanism that could explain the weakening of immune reactions, antibody production and responses to vaccinations, observed in children exposed to PFAS during the prenatal and postnatal period. Coming into contact with perfluoroalkyl substances also increases the serum concentration of inflammatory and oxidative stress markers, favoring the development of systemic diseases, such as liver damage and cardiovascular pathologies.
Finally, research has shown that PFAS compounds are linked to increased levels of several types of lipids: evidence that confirms that exposure to these substances increase the concentration of triglycerides and cholesterol in the blood.