Ten additional PFAS were annotated in dust, including the pesticide fipronil and its transformation products fipronil desulfinyl and flipronil sulfone, which were mainly found in one patient from the iPD group (Figure ). Fipronil, a PFAS-containing pesticide subject to stringent regulations in Europe due to its potential environmental and health-related risks, was (unexpectedly) identified in the dust samples. Although the use of fipronil in food production for human consumption was banned in Europe in 2013, eggs contaminated with fipronil were found in the Netherlands and neighboring countries in 2017 , . The veterinary application of fipronil emerged as a significant potential source of this compound in household dust across Europe. Nonetheless, a prior study conducted in Italy in 2016 noted that the highest levels of fipronil were observed in a household dust without pets . These findings, coupled with our observation of fipronil in German household dust, underscore the necessity for continued regulatory interventions in Europe. Fluorometuron (Figure ), another PFAS-containing pesticide, was also tentatively identified with overall higher peak intensities in the PD-/LRRK2+ dust samples. Additionally, PFAS-containing pharmaceuticals were annotated, including fluoxetine, flutamide, and etofenamate, without significant differences across groups (Figure ). A PFAS with multiple industrial uses, 6:2 fluorotelomer sulfonic acid (6:2 FTSA), had a non-significant lower trend in the PD-/LRRK2+ group compared to the control (Figure ).