Detailed Study of Factors Controlling Atmospheric Concentrations of PCNs
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- 作者：Robert G. M. Lee ; Gareth O. Thomas ; and Kevin C. Jones
- 刊名：Environmental Science & Technology
- 出版年：2005
- 出版时间：July 1, 2005
- 年：2005
- 卷：39
- 期：13
- 页码：4729 - 4738
- 全文大小：259K
- 年卷期：v.39,no.13(July 1, 2005)
- ISSN：1520-5851
文摘
Atmospheric concentrations of polychlorinated naphthalenes(PCNs) (108 samples in total) were measured at two rural/semirural sites in England and one remote site on the westcoast of Ireland in the years 2001 and 2000, respectively.Detailed analysis of the factors affecting concentrations isperformed. At Mace Head (MH) Ireland, concentrationsof 
PCNs ranged between 1.7 and 55 pg m-3 with a meanof 15 pg m-3 and were controlled primarily by advection.PCNs concentrations at Hazelrigg (HR), northwest England,ranged between 31 and 310 pg m-3 with a mean of 110pg m-3, and at Chilton (CH), southwest England, rangedbetween 31 and 180 pg m-3 with a mean of 85 pg m-3. Datafrom the HR site shows that PCN concentrations havenot declined between the early 1990s and 2001, while PCBconcentrations have declined. The ratio of the PCNs/PCBs was close to or greater than 1 at all sites. From airmass back trajectories, it is clear that local/regionalsources influenced concentrations of PCNs at all sites,particularly at MH. At the two English sites during the summer,concentrations of PCNs were strongly influenced bytemperature, indicating that air-surface exchange processesplay an important role. Advection became more influentialduring winter, particularly at CH, where a differenthomologue profile was observed in some samples whenair masses approached from the southwest and PCNconcentrations increased. The average mixture profile ofPCNs in air was similar to that observed in other studies anddifferent from that in Halowax 1014.
PCNs ranged between 1.7 and 55 pg m-3 with a meanof 15 pg m-3 and were controlled primarily by advection.PCNs concentrations at Hazelrigg (HR), northwest England,ranged between 31 and 310 pg m-3 with a mean of 110pg m-3, and at Chilton (CH), southwest England, rangedbetween 31 and 180 pg m-3 with a mean of 85 pg m-3. Datafrom the HR site shows that PCN concentrations havenot declined between the early 1990s and 2001, while PCBconcentrations have declined. The ratio of the PCNs/PCBs was close to or greater than 1 at all sites. From airmass back trajectories, it is clear that local/regionalsources influenced concentrations of PCNs at all sites,particularly at MH. At the two English sites during the summer,concentrations of PCNs were strongly influenced bytemperature, indicating that air-surface exchange processesplay an important role. Advection became more influentialduring winter, particularly at CH, where a differenthomologue profile was observed in some samples whenair masses approached from the southwest and PCNconcentrations increased. The average mixture profile ofPCNs in air was similar to that observed in other studies anddifferent from that in Halowax 1014.