Long-time monitoring of polychlorinated dibenzo-p-dioxins and dibenzofurans over a decade in the ambient air of Porto, Portugal. (October 2015)

• Record Type: Journal Article
• Authors: Coutinho, M.; Albuquerque, M.; Silva, A.P.; Rodrigues, J.; Borrego, C.
• Is Part Of: Chemosphere. Volume 137(2015)
• Page Start: 207
• Page End: 213
• Publication Date: 2015-10
• Subjects: PCDD/PCDF -- Monitoring -- Ambient air concentrations -- Fingerprinting; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2015.07.052
• Languages: English
• ISSNs: 0045-6535

Abstract

Highlights: A trend of PCDD/PCDF levels in ambient air over thirteen years was studied. A decrease on PCDD/PCDF concentrations was found. Seasonal variations and possible sources of the PCDD/PCDF were assessed. Homologue and congener profiles over the years of study were characterized and discussed. Abstract: As part of a monitoring program initiated in 1998 and conducted by IDAD – Institute for Environment and Development and supported by regional municipal solid waste (MSW) management authorities, an extensive database of dioxins' and furans' (PCDD/PCDF) concentrations in ambient air was collected in Porto, in two sites classified as suburban. The present paper summarizes the analytical results of PCDD/PCDF in ambient air obtained from 2001 to 2014 through this intensive monitoring work. The toxic equivalent (WHO-TEQ 1998) concentrations of the PCDD/PCDF in the air ranged from 8.2 to 904.4 fg TEQ m −3, with an average and median values of 104.5 fg TEQ m −3 and 49.8 fg TEQ m −3, respectively. The PCDD/PCDF concentration trend in Porto's ambient air shows a clear drop of the annual average values occurred during the study period. The presence of seasonal variations is very clear in the present study. Winter levels (average: 154.3 fg TEQ m −3 ) are significantly higher than summer levels (average: 42.9 fg TEQ m −3 ). The PCDD/PCDF profiles' details show that several differences occurred over time. The homologue profiles presented changes and the PCDD congeners have decreased in terms of mass. The analysis of concentrations in combination with specific homologue and congener patterns of PCDD/PCDF allowed identification of potential emission sources.