摘要
在2003年11月于天津武清陈楼村采集了7件TSP样品(24h),测定了其中的16种优控PAHs含量。结果表明,不同样品中PAHs谱分布基本一致,表现为中高环化合物占绝对优势,与同一地区城区样品十分相似,但含量为城区样品的1/2左右。研究期间降水造成的湿沉降导致大气中颗粒物及PAHs浓度显著下降,降水过程之后很快恢复到原有水平。不同化合物相对浓度说明测得的主要源于燃煤排放。
Seven TSP samples from one rural site were collected continuously by TH- 150C (100 L· min- 1, 24 h) from 18 November 2003 to 27 November 2003 in Wuqing district, Tianjin city, in order to analyze 16 polycyclic aromatic hydrocarbons (PAHs) classified by the Environmental Protection Agency as priority pollutants. The meteorological parameters, such as wind speed, wind direction and precipitation, were measured during the sampling period. TSP concentrations ranged from 0.061 to 0.428 ng· m- 3, lower than the average concentration (0.625 ng· m- 3) in Tianjin urban area at the same season. 4- to 6- ring PAHs were the major components, accounting for about 90% of the 16 PAHs compounds. Total PAH concentrations in TSP ranged from 10.7 to 543 ng· m- 3, much lower than those analyzed in Tianjin urban area (averaging about 522 ng· m- 3), though the profiles of 16 PAHs were similar to each other. A good relationship between PAH and TSP concentrations was established. From the similar PAHs distribution, we concluded that both rural and urban atmospheric particulate- bound PAHs had the similar sources. The concentrations of TSP and PAHs decreased quickly during precipitation but returned to the former levels immediately after the event. Low- molecular- weight PAHs, such as naphthalene, with relatively high solubility, decreased more rapidly than other compounds. The same scavenging trend was observed for PAHs compounds with equal rings. Based on ratios of Pyrene to Benzo (a)pyrene, Fluoranthene to Pyrene, Benzo(a)pyrene to Benzo(ghi)perylene and Indeno(1,2,3- cd)pyrene to Benzo(ghi)perylene, coal combustion (winter heating) was identified as the major source of PAHs in the rural atmosphere.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2004年第6期1106-1109,共4页
Journal of Agro-Environment Science
基金
国家自然科学基金资助项目(40332015
40021101)
