Dry deposition fluxes and velocities of polychlorinated biphenyls (PCBs) associated with particles

Abstract

The interest in atmospheric deposition by the scientific community has increased a great deal over the past several years because of its significant contribution to the pollution budget of many natural waters. Dry deposition is an effective removal mechanism for polychlorinated biphenyls (PCBs) from the atmosphere. This study focuses on the understanding of the particulate dry deposition of PCBs in urban areas. In this paper, 43 chromatographic PCB congener peaks which represent 50 individual or coeluting congeners were evaluated.The PCB dry deposition fluxes were measured using a smooth, greased, knife-edge surrogate surface holding greased Mylar strips in Chicago, IL. The average PCB dry deposition flux measured (190780 ng m À2 day À1 ) was similar to those measured in other urban areas. Ambient air samples were also collected simultaneously with flux samples. The average apparent dry deposition velocity, calculated by dividing the fluxes to the particle phase concentrations was 5.272.9 cm s À1 . This value is in good agreement with the values calculated using similar techniques.

Particle-phase dry deposition and air–soil gas exchange of polycyclic aromatic hydrocarbons (PAHs) in Izmir, Turkey

“…3). The decrease in deposition velocity with increasing molecular weight is supported by other experimental studies which have shown that a greater fraction of the higher molecular weight PAHs are associated with fine particles relative to the lower molecular weight compounds [4,36,37]. A similar decrease in deposition velocity with increasing molecular weight was previously reported for PAHs [4,5,[33][34][35]38].…”

“…The variation in the dry deposition velocities is a function of particle size distribution and the meteorological conditions (i.e., wind speed and temperature) [34,36]. There was a decrease in dry deposition velocity with increasing molecular weight in this study (Table 2 and Fig.…”

Atmospheric Dry Deposition of Polychlorinated Dibenzo-p-Dioxins/Dibenzofurans (PCDD/Fs) and Polychlorinated Biphenyls (PCBs) in Southern Taiwan

“…The average dry deposition fluxes of PCDD/Fs determined from this study were approximately 2 times lower than those observed at urban area of Japan (36-51 pg I-TEQ/m 2 -day) (Ogura et al, 2001), but similar findings were determined at urban areas of Taiwan (Shih et al, 2006;Wu et al, 2009;Huang et al, 2011), Korea (Moon et al, 2005), and industrial areas of Italy (Guerzoni et al, 2004). As for deposition fluxes of PCBs, values obtained in this study were two to three orders of magnitude lower than the previously reported values measured in suburban site of Turkey (2.1-163 ng/m 2 -day), urban and rural areas of USA, and Tainan, Taiwan (Lee et al, 1996b;Franz et al, 1998;Tasdemir et al, 2004a;Tasdemir and Holsen, 2005;Cindoruk and Tasdemir, 2007) (Table 9). The difference can be attributed to variations in ambient concentrations, sampling techniques, sites, and durations.…”

Spatial character of polychlorinated biphenyls from soil and respirable particulate matter in Taiyuan, China

“…Fine and ultra fine particles can reach lung alveoli, which is responsible for human exposure (Tasdemir et al, 2004;Kampa and Castanas, 2008). Since PCBs can easily accumulate on particles, contamination of soil and respirable PM have a direct impact on public health and increase the risk of human exposure via inhalation and ingestion (Tasdemir et al, 2004;Kampa and Castanas, 2008). Therefore it is important to monitor and improve understanding of various environmental media that influence breathing concentrations of such contaminants.…”

“…Direct human exposure via inhalation of outdoor air is not a significant exposure pathway, with respirable particulate matter (PM) the vector by which POPs enter the upper respiratory tract. Fine and ultra fine particles can reach lung alveoli, which is responsible for human exposure (Tasdemir et al, 2004;Kampa and Castanas, 2008). Since PCBs can easily accumulate on particles, contamination of soil and respirable PM have a direct impact on public health and increase the risk of human exposure via inhalation and ingestion (Tasdemir et al, 2004;Kampa and Castanas, 2008).…”