为探究用典型植物指示环境中全氟化合物(perfluorinated chemicals,PFCs)污染状况的可行性,采用高效液相色谱-质谱联用(high performance liquid chromatography—tandem mass spectrometry,HPLC—MS/MS),分析苔藓、樟树、马尾松、唐菖蒲、地衣、苜蓿、银桦和杜鹃8种植物鲜叶中13种PFCs的残留水平,从中选择富集PFCs能力最强的苔藓为环境生物指示物.结合循环中子活化分析测定深圳市宝安、南山、福田、罗湖、盐田和龙岗6区12个位点苔藓中总氟(total fluorine,TF)、可萃取有机氟(extractable organic fluorine,EOF)和PFCs的含量.结果显示,苔藓中EOF占TF的13.4%~16.5%,表明无机氟为主要存在形态;可鉴别氟(以氟计量的总PFCs)仅占EOF的0.08%~0.15%,显示99.8%以上的EOF仍有待鉴别;全氟辛烷磺酸、全氟己酸、全氟辛酸之和占总PFCs的88%~99%,为苔藓中PFCs主要残留种态;深圳市宝安区苔藓中PFCs残留总量显著高于其他5区(P〈0.01),原因与区内PFCs相关产业密集及其地理气候条件密切相关.利用苔藓指示环境中PFCs污染及其暴露风险是可行的.
In order to assess the feasibility of typical plants as bioindicators for perfluorinated chemicals (PFCs), the residues of 13 PFCs in fresh leaves of moss, camphor tree, masson pine, gladiolus, lichen, alfalfa, silky oak and rhododendron were measured by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Moss, which accumulates PFCs most effectively among the eight, was selected as the environ-mental bioindieator for PFCs assessment. The total fluorine, extractable organic fluorine and PFCs in moss from 12 locations of six Shenzhen districts, including Bao'an, Nanshan, Futian, Yantian, Luohu and Longgang, were measured by cyclic neutron activation analysis combined with HPLC-MS/MS. Results showed that EOF accounted [or 13.4%-16.5% of TF. They indicated that inorganic fluorine was the main form. Only 0. 08%-0. 15% of EOF was the identified fluorine while more than 99.8% of EOF required further identification. The sum of perfluorooctane sulfonate, perfluorooctanoic acid and perfluorohexanoic acid accounted for 88%-99% of total PFCs, making them the main PFCs species in moss. Total PFCs residues in moss from Bao'an district were significantly higher than those from other districts (P 〈 0.01), which was likely due to the presence of PFCs-related industries, geographical location and climate. The results suggest that moss is a feasible bioindicator for PFCs and its exposure risk in the environment.