Levels and gas-particle partitioning of POPs in urban ambient air.

Abstract

Air pollution continues to be a major health, environmental, and economic issue in Europe, because it leads to health problems, premature deaths and damage to ecosystems, crops and buildings1. Despite progress in reducing air pollution, certain pollutants such as particulate matter (PM) remain a significant threat. PM is a complex and heterogeneous mixture of inorganic and organic substances, and constitutes the greatest risk in terms to harm the human health, especially in urban areas where the majority of the European population lives. Persistent Organic Pollutants (POPs), and emerging pollutants as flame retardants, are some of the wide extent of dangerous chemicals which can be found in the ambient air. They are present in the gas phase and also adsorbed on the suspended particulate matter, depending on ambient temperature and the physico-chemical properties of the chemical. Due to their toxic, bio-accumulative and persistent characteristics these pollutants are matter of great concern for human health and natural ecosystems3. However there are several data gaps related to their fractionation in ambient air. Therefore improving our knowledge of POPs in this matrix remains a challenge. The aim of this study was to evaluate the presence of several POPs in ambient air samples from the city of Madrid (Spain). Gas phase and airborne particulate matter were studied separately. Levels and fractionation of the following analytes were studied: polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs: (the 2,3,7,8-substituted congeners), polychlorinated biphenyls (PCBs): dioxin-like PCBs (dl-PCBs: CB-81, -77, -123, -118, -114, -105, -126, -167, -156, -157, 169 and -189) and indicator PCBs (i-PCBs: CB-28, -52, -101, -138, -153 and -180), polybrominated diphenyl ethers (PBDEs: tri to deca-BDE) and Dechloranes (Dec 602, Dec 603, Dec 604, Dec 605 also called Dechlorane Plus (DP), Chlordane Plus (CP) and Mirex). The levels measured were consistent with those reported in other studies. Results evidence that PBDEs, PCDD/Fs and DP were primarily bounded to particle phase, while i-PCBs and dl-PCB were mainly associated to gas-phase. Further investigation will be necessary to evaluate potential seasonal variations.