Interstudy and Intrastudy Temporal Trends of Polychlorinated Biphenyl, Pesticide, and Polycyclic Aromatic Hydrocarbon Concentrations in Air and Precipitation at a Rural Site in Ontario

详细信息    查看全文

• 作者：Liang-Ying Liu ; Amina Salamova ; Ronald A. Hites
• 刊名：Environmental Science & Technology Letters
• 出版年：2014
• 出版时间：April 8, 2014
• 年：2014
• 卷：1
• 期：4
• 页码：226-230
• 全文大小：249K
• 年卷期：v.1,no.4(April 8, 2014)

文摘

Polychlorinated biphenyl (PCB), organochlorine pesticide, and polycyclic aromatic hydrocarbon (PAH) concentrations were measured in air (in the vapor and particle phases) and in precipitation samples collected at Point Petre on the northeastern shore of Lake Ontario as a part of the Integrated Atmospheric Deposition Network. These data were measured in two separate studies, one running from 1992 to 2003 (inclusive) and the other from 1998 to 2011 (inclusive). Having these two independent studies is a direct way of measuring changes in atmospheric concentrations and comparing interstudy changes to intrastudy changes. The concentrations of almost all pesticides declined between the two studies with halving times of 3鈥? years; the concentrations of PAHs and PCBs did not change much between the two studies. This suggests that there are continuing sources of PAHs and PCBs to the Great Lakes atmosphere. PAH concentrations were elevated in the winter when space heating consumes greater amounts of fuel and emits larger amounts of PAHs. Pesticide and PCB concentrations were elevated in the summer because of enhanced volatilization from terrestrial or aquatic surfaces during hot summer days. Although there were a few exceptions (notably lindane), in general, the data from the two study periods gave similar results.