This study analyzed fire fighters' multiple exposures to perfluoroalkyl acids (PFCs) and 2-butoxyethanol found in aqueous film-forming foams (AFFFs). The study aimed to analyze PFC profiles in used foam, assess firefighter exposure, and evaluate eight AFFFs. Serum samples before and after training sessions found increased excretion of PFOA, PFNA, PFHxS, and PFOS in firefighters. Urinary samples also showed exposure to 2-butoxyethanol exceeding limits for the general population. The study concluded that firefighter exposure to PFCs was higher than the general population and increased during training. PFHxS showed the highest increase, making it