Unit of Epidemiology, Department of Preventive Medicine, Fondazione IRCCS Ca' Granda--Ospedale Maggiore Policlinico, Milan, Italy.
Med Lav. 2012 Jul-Aug;103(4):259-67.
The Seveso accident (Italy) in 1976 caused the contamination of a large population by 2,3,7,8-tetrachlorodibenzo-para-dioxin (2,3, 7,8-TCDD). The contaminated territory was divided into three zones: A (very high contamination), B (high contamination), and R (low contamination). We report here the plasma concentrations of seven polychlorinated dibenzo-para-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), four non-ortho-polychlorinated biphenyls PCBs (nPCBs), and Toxic Equivalencies (TEQs) in a sample of residents in the most polluted zones A and B and in a reference non-contaminated zone.
From December 1992 to March 1994, 62 individuals were randomly selected from the population living in zone A (No. =7) and B (No. =55). A sample of 59 subjects living in a surrounding non-contaminated area (non-ABR), frequency-matched by gender, age, and smoking history, was used as reference. All subjects were administered a questionnaire surveying demographic, lifestyle, medical history, and accident-related factors. We assayed plasma PCDD, PCDF, and nPCB concentrations by high-resolution gas chromatography/high resolution mass spectrometric (HRGC/HRMS) analysis, with results reported as pg/g of lipid, or parts per trillion (ppt). We calculated TEQs using the WHO 2005 Toxic Equivalency Factors (TEFs).
We found elevated median levels of 2,3, 7,8-TCDD in plasma samples of subjects living in zone A (73.3 ppt) and zone B (12.4 ppt), compared with residents in the reference zone (5.5 ppt). In analyses adjusted for gender, age, smoking, and body mass index (BMI), none of the other congeners showed levels higher than reference in the contaminated zones. Compared with men, women showed higher levels (113%) of 2,3, 7,8-TCDD and a slight elevation (17%) of TEQ for the other congeners. Age was strongly positively associated with most congener levels; TEQs for PCDDs, PCDFs, and nPCBs showed respectively 12%, 24%, and 41% increases for every 10 years of age. Current smokers had lower (from -37% to -67%) TEQ levels than subjects who had never smoked. BMI was negatively associated with levels of a few congeners, but with no impact on TEQ values.
The Seveso accident caused a severe exposure of the population to 2,3,7,8-TCDD only. None of the other congeners analyzed showed variation across zones. Age showed a strong positive association with TEQs for all classes of compounds (PCDDs, PCDFs, and nPCBs).
1976 年的塞维索事故（意大利）导致大量人群受到 2,3,7,8-四氯二苯并对二恶英（2,3,7,8-TCDD）的污染。受污染的地区被分为三个区域：A（高度污染）、B（中度污染）和 R（低度污染）。我们在此报告了居住在污染最严重的 A 区和 B 区的居民以及一个未受污染的参考区的 7 种多氯二苯并对二恶英（PCDDs）、10 种多氯二苯并呋喃（PCDFs）、4 种非邻位多氯联苯（nPCBs）和毒性等效物（TEQs）的血浆浓度。
1992 年 12 月至 1994 年 3 月，从居住在 A 区（编号=7）和 B 区（编号=55）的人群中随机选择了 62 人。使用了居住在周围未受污染地区（非 ABR）的 59 名年龄、性别和吸烟史相匹配的受试者作为参考。所有受试者均接受了一项问卷调查，调查人口统计学、生活方式、病史和与事故相关的因素。我们通过高分辨率气相色谱/高分辨率质谱（HRGC/HRMS）分析测定了血浆 PCDD、PCDF 和 nPCB 浓度，结果以每克脂质或每万亿分之几（ppt）报告。我们使用世界卫生组织 2005 年的毒性等效因子（TEFs）计算了 TEQs。
与参考区的居民（5.5 ppt）相比，居住在 A 区（73.3 ppt）和 B 区（12.4 ppt）的受试者的血浆样本中，2,3,7,8-TCDD 的中位数水平升高。在调整了性别、年龄、吸烟和体重指数（BMI）后，在污染区没有其他同系物的水平高于参考值。与男性相比，女性的 2,3,7,8-TCDD 水平更高（113%），其他同系物的 TEQ 水平略有升高（17%）。年龄与大多数同系物水平呈强烈正相关；PCDDs、PCDFs 和 nPCBs 的 TEQs 分别增加了 12%、24%和 41%，每增加 10 岁。目前吸烟的受试者的 TEQ 水平比从不吸烟的受试者低（-37%至-67%）。BMI 与少数同系物的水平呈负相关，但对 TEQ 值没有影响。
塞维索事故导致人群严重接触 2,3,7,8-TCDD。分析的其他同系物在各区域之间没有变化。年龄与所有类别的化合物（PCDDs、PCDFs 和 nPCBs）的 TEQs 呈强烈正相关。
