广州白云山风景区阔叶植物叶片中的多环芳烃

Polycyclic aromatic hydrocarbons in leaves of broadleaved plants from Baiyun Mountain, Guangzhou

多环芳烃(PAHs)在环境中分布极广,作为持久性亲脂有机污染物,具有很强的生物累积性。植物对周围环境有着高度的依赖性,阔叶植物由于叶面巨大的表面积,容易吸收富集环境中的多环芳烃。采集了白云山9种阔叶植物叶片样品,利用GC-MS对样品中的多环芳烃进行了定量分析。结果表明,白云山阔叶植物叶片样品中的PAHs以芘所占比例最高,总PAHs为460.2～1303.5ng·g-1(干质量)。从组成上看,白云山阔叶植物叶片中多环芳烃以3环、4环为主,比较发现这种组成特征与大气中PAHs相似。运用分子标志物比值法分析PAHs的来源,发现阔叶植物样品中PAHs主要是热成因来源。广州市工业发达,环境中含有较高PAHs在白云山阔叶植物叶片中已有明显的反映,应加强对环境中PAHs监控和治理。

Polycyclic aromatic hydrocarbons （PAHs） are ubiquitous compounds in the environment. As Persistent Organic Pollutants, PAHs have strong bioaccumulative properties. The leaves of Broadleaved plants can accumulate PAHs easily because of their large surface area. 16 PAHs in the leaves of 9 kinds of broadleaved plants from Baiyun Mountain in Guangzhou were separated and analyzed quantitatively by GC-MS. The results showed that the concentration of pyrene was highest in PAHs of leaves and the ΣPAHs ranged from 460.2 to 1303.5 ng·g^-1 dry weight. 3- and 4-ring PAHs compounds were the main components of the 16 PAHs and the compositions were well correlated with PAHs in the atmosphere deposition . Ratios of indicator PAHs （Phe/ Ant） method was applied and indicated that the PAHs in the broadleaved plants’ leaves mainly had a pyrolytic origin. It is clear that the developed industry in Guangzhou has led to high PAHs in the surrounding environment, which is reflected by the content of PAHs in leaves of broadleaved plants from Baiyun Mountain. The control and management of PAHs in environment should be strengthened.