Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm, Sweden.
Environ Int. 2013 Oct;60:224-31. doi: 10.1016/j.envint.2013.08.019. Epub 2013 Sep 27.
Temporal trends of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in mothers' milk are still quite rare. Data are particularly scarce when it comes to concentrations from the last decade, 2000 and onwards. The aims of the present study were to assess temporal trends of PCDD, PCDF and DL-PCB in mothers' milk from Stockholm, 1972-2011 and to compare the results with previous analysis of some of the older samples. The samples were analyzed by high resolution GC/MS and results were statistically evaluated for the periods, 1972-2011 and 2002-2011. The rate of which ∑PCDDs, ∑DL-PCBs and the ∑TEQ are decreasing (on pg/g fat WHO-TEQ2005) is higher in the last decade compared to the 40year period, 1972-2011. A similar trend is indicated, but not confirmed, for ∑TEQ of PCDFs, probably due to too many PCDF congeners below LOQ in the period 2002-2011. Concentrations of ∑PCDDs, ∑PCDFs, ∑DLPCBs and ∑TEQ, all expressed as pg/g fat on TEQ-WHO2005-basis, show a statistically significant decline over time, 5.8-6.8% per year, 1972-2011. The last ten years the annual declines for ∑PCDDs, ∑DL-PCBs and ∑TEQ are 9.2-11% and for ∑PCDF, 5.4%. Congener specific trend analysis, 2002-2001, of PCDDs and DL-PCBs showed the same pattern, while the PCDF congeners showed no such general trend. The results from the re-analysis showed good agreement with slightly lower ∑TEQ1998 pg/g fat concentrations in six out of seven samples and mean difference of 13% in ∑TEQ1998. The study shows that time series can be elongated from previous studies, as long as the sample population remains the same.
母乳中多氯二苯并对二恶英（PCDDs）、二苯并呋喃（PCDFs）和类似二恶英的多氯联苯（DL-PCBs）的时间趋势仍然相当罕见。特别是在过去十年，即 2000 年及以后的数据非常稀缺。本研究的目的是评估 1972 年至 2011 年斯德哥尔摩母乳中 PCDD、PCDF 和 DL-PCB 的时间趋势，并将结果与之前对一些较旧样本的分析进行比较。这些样本通过高分辨率 GC/MS 进行分析，并对 1972 年至 2011 年和 2002 年至 2011 年两个时期的结果进行了统计学评估。与 1972 年至 2011 年的 40 年期间相比，∑PCDDs、∑DL-PCBs 和∑TEQ（按 WHO-TEQ2005 计算）的下降速度在过去十年中更高。PCDFs 的∑TEQ 也显示出类似的趋势，但由于 2002 年至 2011 年期间太多的 PCDF 同系物低于 LOQ，因此无法得到证实。∑PCDDs、∑PCDFs、∑DLPCBs 和∑TEQ（均以 TEQ-WHO2005 为基础表示为 pg/g 脂肪）的浓度随着时间的推移呈统计学显著下降，1972 年至 2011 年每年下降 5.8-6.8%。过去十年中，∑PCDDs、∑DL-PCBs 和∑TEQ 的年降幅分别为 9.2-11%，∑PCDF 的年降幅为 5.4%。2002-2001 年对 PCDD 和 DL-PCB 的同系物特异性趋势分析显示出相同的模式，而 PCDF 同系物则没有这种普遍趋势。重新分析的结果与七个样本中的六个样本中∑TEQ1998pg/g 脂肪浓度略低以及∑TEQ1998 的平均差异 13%的结果相吻合。该研究表明，只要样本人群保持不变，就可以从以前的研究中延长时间序列。
