“… 467 The respiratory and cardiovascular systems become the primary targets, with potential consequences ranging from irritations (e.g., coughing) to chronic cardiopulmonary diseases (e.g., hypertension and chronic obstructive pulmonary diseases). 468 , 469 A recent meta-analysis comprising 13 studies showed that higher exposure levels of PFAS, especially for perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid, were significantly associated with a higher risk of hypertension. 470 Notably, particulates with smaller sizes are much more harmful than larger particles because of the longer residence time and greater capacity for deeper penetration in the respiratory tract.…”