# PFAS: The Journey from Wonder Chemicals to Environmental Nightmares and the Search for Solutions
### Health Impacts of PFAS Exposure  
The persistence of PFAS in the environment and their accumulation in human tissues have raised significant health concerns. Numerous studies have documented the adverse effects of PFAS exposure on various organ systems, highlighting the need for increased awareness and regulatory actions. PFAS exposure has been shown to induce metabolic dysregulation and phenotypic changes in hepatocytes, leading to hepatotoxicity, oxidative stress, and inflammatory responses. These changes underscore the potential health risks associated with PFAS exposure, particularly regarding liver health [16; 17; 18; 19]. In children, PFAS exposure has been linked to a slight decrease in antibody responses and potential associations with childhood infections, particularly with specific compounds such as PFOS, PFOA, PFHxS, and PFNA. This suggests that even low levels of PFAS exposure during childhood could lead to compromised immune function and increased susceptibility to infections [20]. PFAS also impacts female reproductive health, with evidence linking exposure to conditions like polycystic ovary syndrome (PCOS), endometriosis, premature ovarian \begin{table}
\begin{tabular}{c||c c c c c c c c c} \hline \hline \multirow{2}{*}{
\begin{tabular}{c} **Molecule** \\ **Type** \\ \end{tabular} } & \multicolumn{6}{c}{**Number of Carbon Atoms**} \\ \cline{2-10}  & \multicolumn{2}{c}{**Shot-Chain PFCAS**} & \multicolumn{2}{c}{**Long-Chain PFCAS**} & \multicolumn{2}{c}{**Short-Chain PFSA**} & \multicolumn{2}{c}{**Long-Chain PFSA**} \\ \cline{2-10}  & **4** & **5** & **6** & **7** & **8** & **9** & **10** & **11** & **12** \\ \hline
**PFCA** & PFBA & PFFeA & PFHxA & PFHpA & PFOA & PFNA & PFDA & PFDA & PFDA \\ \hline PFSA & PFBS & PFPeS & PFHxS & PFHxS & PFOS & PFNS & PFBS & PFUs & PFUs & PFUs \\ \hline \hline \end{tabular}
\end{table} 
Table 1: PFAS classification according to the Carbon chain length. insufficiency (POI), and diminished ovarian reserve (DOR). These findings emphasize the need for further research to understand the mechanisms by which PFAS affect ovarian function and reproductive health [21]. Furthermore, PFAS accumulates in the liver and kidneys, where they can interfere with liver transporters and contribute to adverse health outcomes, such as increased serum cholesterol levels. Understanding the interaction between PFAS and liver transporters is crucial for assessing the risks associated with PFAS exposure [22]. PFAS have been found to induce immune-toxic effects at low levels, potentially leading to reduced immune responses and increased susceptibility to infections and diseases. Computational models, such as agent-based modelling (ABM) and physiologically based kinetic (PBK) models, are being used to understand PFAS mechanisms better and inform risk assessments and regulatory decisions [23]. PFAS exposure is also associated with a range of health issues, including thyroid disorders, kidney dysfunction, liver damage, and an increased risk of certain cancers [24]. Additionally, PFAS exposure has been linked to DNA methylation changes, which may disrupt normal gene expression and contribute to the development of cancer and other health disorders. The potential effects of PFAS on pregnancy outcomes, including complications and impacts on fetal development, further underscore the need for comprehensive research on PFAS exposure, particularly in vulnerable populations like pregnant women and children [21; 25]. The binding of PFAS to serum proteins varies based on carbon chain length, affecting their toxicity and elimination of half-lives. Understanding this variability is essential for predicting PFAS behavior in human serum and assessing associated health risks [26]. Epidemiological studies have demonstrated that PFAS exposure is associated with increased risks of certain cancers, reduced immune function, and developmental delays in infants. Moreover, PFAS may disrupt endocrine functions, leading to metabolic and thyroid disorders, particularly in vulnerable populations such as postmenopausal women [27].