Yapay Zeka Hızlı Bakış & Çıkarımlar
AI InsightBased on these results, the inhalation risk for PCDD/Fs and dl-PCBs, for local Sao~ Paulo residents, should be considered low.
📌 3 Maddede Bu Makale
Özet
Thirty-five and eleven air samples were collected using, respectively, active samplers (filter þ PUF) and passive samplers (PUF disks), over two consecutive four-month periods (spring and autumn-winter), in urban, urban/industrial, and rural (background) sites in Sao~ Paulo, Brazil. All the samples were extracted with toluene:acetone (9:1) in a Soxhlet apparatus, and the extracts were then purified. Analysis for polychlorinated dioxins and furans (PCDD/Fs) and for dioxin-like polychlorinated biphenyls (dl-PCBs) were made by High Resolution Gas Chromatography/High Resolution Mass Spectrometry (HRGC-HRMS). Human exposure risk was evaluated using inhalation risk assessment. Results showed: (1) there are statistical differences for PCDD/F concentrations in air between periods 1 and 2 (p ¼ 0.03), whereas dl-PCB levels were not statistically different (p ¼ 0.52); (2) PCDD/F and dl-PCB air levels were in the following order: urban/industrial > urban > rural for both active and passive samples; (3) PCDD/F and dl-PCB concentrations ranged from 7.76 to 453 fg TEQ/m3 in active air samples, and from 6.11 to 469 fg TEQ/ m3 in passive air samples; (4) sampling rates for PCDD/Fs by the two approaches used showed considerable differences; (5) average daily intake by inhalation ranged from 18.1 to 55.6 fg TEQ/kg day, respectively, for adults and children, representing 1.8e5.6% of the lower range of the Tolerable Daily Intake recommended by the World Health Organization. Based on these results, the inhalation risk for PCDD/Fs and dl-PCBs, for local Sao~ Paulo residents, should be considered low.