Schuhmacher M, Domingo J L, Llobet J M, Sünderhauf W, Müller L
Department of Chemical Engineering, Rovira i Virgili University, Tarragona, Spain.
Sci Total Environ. 1998 Jul 30;218(2-3):175-83. doi: 10.1016/s0048-9697(98)00202-2.
In 1996, the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were determined by HRGC/HRMS in 24 vegetation samples collected in the vicinity of a municipal solid waste incinerator (Tarragona, Catalonia, Spain). In the present study 24 vegetation samples were again taken at the same sampling points and analyzed for the levels of PCDD/Fs. The results were compared with those obtained in the previous survey. While in the 1996 study, PCDD/F levels ranged from 0.15 to 62.09 ng I-TEQ/kg (dry matter) (median value, 0.33 ng I-TEQ/kg; mean value, 4.11 ng I-TEQ/kg), the concentrations of PCDD/Fs in the 1997 survey ranged between 0.11 and 0.50 ng I-TEQ/kg (dry matter) (median value, 0.20 ng I-TEQ/kg; mean value, 0.23 ng I-TEQ/kg). The individual comparison between PCDD/F levels in the samples collected in 1996 and 1997 showed a decrease in 15 of the 24 sampling points. When the comparison was carried out in relation to each of the four main wind directions in the area, the highest decrease in PCDD/F concentrations (64%) corresponded to samples in the SE direction, while those in the NE direction showed also a notable reduction in total I-TEQ (44%). In contrast, PCDD/F levels in vegetation samples from NW and SW directions were increased (37% and 6%, respectively). When the data were evaluated according to the distance of the sampling points to the plant, the highest decrease in total I-TEQ was found at 500 m from the stack. The results of this study seem to provide evidence for a decline in atmospheric emissions of PCDD/Fs in the area of Tarragona.
1996年，采用高分辨气相色谱/高分辨质谱法（HRGC/HRMS）测定了在一座城市固体废物焚烧厂（位于西班牙加泰罗尼亚自治区塔拉戈纳市）附近采集的24份植被样本中多氯二苯并对二恶英（PCDDs）和二苯并呋喃（PCDFs）的浓度。在本研究中，于相同采样点再次采集了24份植被样本，并对其中PCDD/Fs的含量进行了分析。将结果与先前调查所得结果进行了比较。在1996年的研究中，PCDD/Fs含量范围为0.15至62.09纳克毒性当量/千克（干物质）（中位数为0.33纳克毒性当量/千克；平均值为4.11纳克毒性当量/千克），而在1997年的调查中，PCDD/Fs浓度在0.11至0.50纳克毒性当量/千克（干物质）之间（中位数为0.20纳克毒性当量/千克；平均值为0.23纳克毒性当量/千克）。对1996年和1997年采集的样本中PCDD/Fs含量进行的个体比较显示，24个采样点中有15个采样点的含量有所下降。当按照该地区四个主要风向分别进行比较时，PCDD/Fs浓度下降幅度最大（64%）的是东南方向的样本，而东北方向样本的总毒性当量也显著降低（44%）。相比之下，西北和西南方向植被样本中的PCDD/Fs含量有所增加（分别增加了37%和6%）。当根据采样点与工厂的距离对数据进行评估时，在距离烟囱500米处发现总毒性当量下降幅度最大。本研究结果似乎为塔拉戈纳地区PCDD/Fs的大气排放量下降提供了证据。
