Polar organic chemicals in indoor depositions from Italian hospitals during the CoViD-19 outbreak

Few studies were focused on pollution in hospitals and on dusts (DD) affecting their interiors. Moreover, no investigations were performed in Italian hospitals on DD-associated organic compounds. From 2019 to 2023, we conducted four measurement campaigns aimed at elucidating chemical composition of indoor DD from three Italian hospitals during the CoViD-19 outbreak course. In 2021, measurements were undertaken at another hospital hosting a vaccine hub. Parallel measurements were performed at a university and a private dwelling, and in 2022-2023 included outdoor DDs. Ultrasonic extraction, column chromatography and GC-MSD were applied to characterize DD. This paper focuses on polar organic compounds (POCs). Primary attention was paid to phthalate esters, psychotropic substances, bisphenol-A, alkyl phenols, organic phosphates, UV filters, and fragrances. Their concentration levels, molecular fingerprints, time trends and indoor/outdoor relationships were elucidated. All compounds exhibited wide changes of DD loads during outbreak. Phthalates ranged <0.1 to >13 mg/g of dust, declining with time, organic phosphates ranged <0.03-0.3 mg/g, declining up to 2022 and raising again in 2023. At hospitals, nicotine and cocaine ranged <2.0-45 μg/g and ∼5-65 μg/g, respectively, raising from 2019 to 2023. Emerging organic contaminants (including fatty acid esters and plasticizers) were evaluated, while new chemicals, e.g. indigo, seemed linked to CoViD-19 outbreak course. Internal sources and the rate of people frequentation presumably caused the peculiarity of DD composition at hospitals vs. dwelling and university, and to higher loads observed indoors. DD-related non-dietary daily intake by hospital workers ranged ∼1-100 μg for phthalates and ∼0.1-10 μg for organic phosphates.