汕头经济特区土壤中优控多环芳烃的分布

Distribution of priority polycyclic aromatic hydrocarbons in soils in Shantou Specific Economic Zone

运用气相色谱-质谱方法对汕头经济特区131个土样中的美国EPA优控多环芳烃(PAHs)进行定性、定量测定,讨论了PAHs的分布特征.结果表明,该区表层土壤中优控PAHs的总质量分数范围从22.1ng/g到1256.9ng/g之间,平均质量分数为(317.3±210.2)ng/g.其分布随采样点的位置不同而有显著变化:工业区附近多环芳烃的质量分数最高,城市中心次之,郊区最低.大多数样点中∑PAHs质量分数和单种PAH质量分数都呈现w(5～20cm)＞w(0～5cm)＞w(20～40cm)＞w(40～100cm)的垂直分布规律.该区土壤PAHs以3环和4环化合物为主,单种PAH以萘、菲和苯并[b]萤蒽为主.

The distributions of priority polycyclic aromatic hydrocarbons (PAHs) were investigated in soils in Shantou Specific Eco-nomic Zone. 131 soil samples including 115 surface samples and 16 profile samples were collected during March and April, 2002, and PAHs were identified by using gas chromatography linked to mass spectrometry (GC-MS). The ?PAH concentrations ranged from 22.1 to 1256.9 ng/g with a mean value of (317.3210.2) ng/g. The concentrations of PAHs varied spatially with a great extent while the vertical distribution of ?PAH and individual PAH in 4 soil layer decreased with the order of w(5~20 cm)>w(0~5 cm)>w(20~40 cm)>w(40~100 cm) in the most soil cores. Compared with the suburb area, the industrial estates area and center area of the city were more heavily polluted. The dominant PAHs were 3-ring and 4-ring of PAHs, and the predominant individual PAHs were naphthalene, phe-nanthrene and beozo [b] fluornthene.