九龙江河口区多环芳烃分布逸度模型和实测分析

于2011年12月(冬季)在厦门九龙江河口及西港采集9个表层海水水样,采用固相萃取-气质联用方法(SPE-GC-MS)分析其中16种多环芳烃含量。研究结果表明,总溶解态态PAH含量为157.9~858.0 ng/L。在河口区,随着盐度升高,PAHs含量逐渐降低。基于比值法分析,表明厦门九龙江及西港海域海水中的PAHs来源存在多种途径,呈现混合来源的态势。利用LEVEL Ⅲ逸度模型研究菲,芘和苯并(a)芘在各介质间的分布以及水气界面的交换通量。模拟结果与本文实测和文献中的实测值相吻合。在16℃时,三种多环芳烃的大气沉降通量分别为17.38,7.86和8.38g/day/m2。其中菲在大气沉降中占主导地位,约三分之二。三种多环芳烃的大气沉降通量均随温度升高而减少。当温度高于32℃时,苯并(a)芘开始从水体释放。

Distribution pattern of PAHs in Jiulong River Estuary by both measurement and simulation

The concentration of 16 polycyclic aromatic hydrocarbons(PAHs) of nine water samples, collected in the Jiulong River Estuary in December, 2011, were analyzed using the SPE-GC-MS method. The results showed that the concentration range of total dissolved PAHs(PAHs) was from 157.9 to 858.0 ng/L. The horizontal distribution illustrated that the concentration of PAHs decreased as salinity increased. Based on ratio analysis, PAHs have complicated sources. A Level Ⅲ fugacity model was developed to simulate the multimedia fate of PAHs and to study the air-water exchange fluxes of three PAHs(phenanthrene, pyrene, benzo[a]pyrene) in the Jiulong River Estuary. The calculated concentration of PAHs was similar to that measured in this study or reported in earlier literature. At 16℃, the net atmosphere deposition fluxes of these PAHs were 17.38, 7.86 and 8.38g/day/m2. Phenanthrene was predominant in the atmospheric deposition. The net atmospheric deposition fluxes of these PAHs all decreased with temperature. When the temperature was above 32.0℃, benzo[a]pyrene was released from the water into the air.