Djordjevic M V, Fan J, Hoffmann D
Division of Environmental Carcinogenesis, American Health Foundation, Valhalla, NY, USA.
Carcinogenesis. 1995 Nov;16(11):2627-32. doi: 10.1093/carcin/16.11.2627.
It has been established that the organochlorinated compounds (OCC) DDT and DDE are xenoestrogens which influence both normal and neoplastic estrogen-responsive tissues. Therefore, it has been hypothesized that OCC contribute to the risk for breast cancer. Although the food chain has been recognized as a major source of human exposure to these compounds, tobacco and tobacco smoke were also considered as sources of exposure to OCC. This study was aimed at quantifying OCC in tobacco and cigarette smoke and at documenting changes in the concentrations of these pesticides in tobacco products since 1970 when OCC were banned for use on tobacco. To determine the levels of OCC residues on tobacco, we developed a new method based on superficial fluid extraction, followed by clean-up on an alumina column, and analysis by gas chromatography with electron capture detection. The detection limit for an individual OCC is 1 ng/g tobacco, the relative SD is < 10% for each analyte and the new method compares well with the standardized method that involves conventional organic solvent extraction. The major OCC determined in the tobaccos and in cigarette smoke of US commercial brands that were manufactured in the proceeding three decades were p.p'-isomers of DDD (1540-20 220 ng/g tobacco), DDT (720-13 390 ng) and DDE (58-730 ng). Since 1970, the concentrations of individual OCC in tobacco have gradually decreased by > 98%. The transfer rate from tobacco into mainstream smoke amounts to 22% for DDD, 19% for DDT and 27% for DDE. Today, the concentrations of the OCC in US tobacco are below the maximum permissible limits set by the Environmental Protection Agency. While until 1970 the OCC in tobacco and tobacco smoke contributed significantly to the bioaccumulation of the pesticides in smokers, at this time tobacco and cigarette smoke are a minor source of human exposure.
已证实有机氯化合物（OCC）滴滴涕（DDT）和滴滴伊（DDE）是外源性雌激素，会影响正常和肿瘤性雌激素反应组织。因此，有人提出假设，OCC会增加患乳腺癌的风险。尽管食物链已被认为是人类接触这些化合物的主要来源，但烟草和烟草烟雾也被视为OCC的接触源。本研究旨在对烟草和香烟烟雾中的OCC进行定量，并记录自1970年OCC被禁止用于烟草以来这些烟草制品中这些农药浓度的变化。为了测定烟草上OCC残留水平，我们开发了一种基于表面流体萃取的新方法，随后在氧化铝柱上进行净化，并通过带有电子捕获检测的气相色谱法进行分析。单个OCC的检测限为1 ng/g烟草，每种分析物的相对标准偏差<10%，并且该新方法与涉及传统有机溶剂萃取的标准化方法相比效果良好。在过去三十年生产的美国商业品牌烟草及其香烟烟雾中测定的主要OCC是滴滴滴（DDD）的对，对'-异构体（1540 - 20220 ng/g烟草）、DDT（720 - 13390 ng）和DDE（58 - 730 ng）。自1970年以来，烟草中单个OCC的浓度已逐渐下降超过98%。从烟草转移到主流烟雾中的比例，DDD为22%，DDT为19%，DDE为27%。如今，美国烟草中OCC的浓度低于美国环境保护局设定的最大允许限量。虽然直到1970年烟草和烟草烟雾中的OCC对吸烟者体内农药的生物累积有显著贡献，但此时烟草和香烟烟雾是人类接触的次要来源。
