Al Farabi Kazakh National University, Avenue Al Farabi 71, 050040 Almaty, Kazakhstan.
Chemosphere. 2011 Oct;85(3):351-60. doi: 10.1016/j.chemosphere.2011.06.097. Epub 2011 Jul 22.
To date, despite the fact it represents a very important part of the national dairy production, no data are available concerning the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) in camel milk from the Republic of Kazakhstan. Selected PCDDs, PCDFs, and PCBs were measured in pools of milk from camels (n=15) located in various places of Kazakhstan (Almaty, Atyrau, Aralsk, Shymkent) and sampled at two different seasons for two different species (Camelus bactrianus and Camelus dromedarius). Non-dioxin-like (NDL-)PCB concentrations (6.3±2.7 ng g(-1) fat, median 5.1 ng g(-1) fat, range 0.6-17.4 ng g(-1) fat) were far below the maximum value of 40 ng g(-1) fat proposed by the EU. Dioxin-like (DL-)PCB concentrations (1.7±0.7 ng g(-1) fat, median 1.5 ng g(-1) fat, range 0.3-4.2 ng g(-1) fat) and the NDL-PCB to DL-PCB ratio (4.3) were similar to what is reported in EU for cow-based dairy products. PCB 52 and PCB 101 appeared to be proportionally more present in Kazakh camel milk samples (>60% of the sum of the 6 indicator NDL-PCBs) than in European cow milk samples (<10% of the sum of the 6 indicator NDL-PCBs), indicating possible differences in the route of exposure to PCBs in Kazakhstan. PCB 105 and PCB 118 appeared to be present at higher concentrations in camel milk (>80% of the sum of the 12 DL-PCBs). PCB 105, PCB 118 and PCB 156 were the major congeners for DL-PCBs, accounting for 92% of the sum of concentrations of DL-PCBs (88% for Belgian cows). In terms of TEQ, PCB 126 and PCB 118 are the major contributors and represent, respectively, 80% and 14% of the DL-PCB TEQWHO05 concentrations. No significant interracial or geographical trends were observed for NDL- and DL-PCB profiles. However, concentrations of all DL-PCBs appeared to be significantly higher for samples collected in Atyrau region. 2,3,7,8-TCDD level (mean 0.08±0.07 pg g(-1) fat, median 0.08 pg g(-1) fat, range 0.00-0.18 pg g(-1) fat, 60%>LOQs) were very low for all samples and 2,3,4,7,8-PeCDF was the major contributor (27%) to the PCDD/F TEQWHO05. Considering the total TEQWHO05 (sum of DL-PCBs and PCDD/Fs), DL-PCB and PCDD/F contributed for 73% and 27%, respectively. A decrease of only 1% of the total TEQ was observed when using the TEFWHO05 scale instead of the TEFWHO98 scale. Two samples collected in the region of Atyrau exceeded the EU maximum level value of 6.00 pg TEQWHO98 g(-1) fat (6.4 pg TEQWHO05 g(-1) fat and 6.9 pg TEQWHO05 g(-1) fat). Both samples exceeded the EU action level for the sum of DL-PCBs. Based on the fact that camel milk is used to prepare popular traditional fermented drinks like shubat, this suggests that the human exposure in the Caspian Sea region of Atyrau should be expected to be higher than in the other regions studied here.
迄今为止，尽管骆驼奶在哈萨克斯坦的奶制品生产中占有非常重要的地位，但目前还没有关于其多氯二苯并对二恶英（PCDDs）、多氯二苯并呋喃（PCDFs）和多氯联苯（PCBs）浓度的相关数据。本研究选取了来自哈萨克斯坦各地（阿拉木图、阿特劳、阿拉尔斯克、希姆肯特）的骆驼奶样本（n=15），并在两个不同季节进行了采集，用于分析两种不同的骆驼品种（双峰驼和单峰驼）。研究结果表明，非二恶英类（NDL-）多氯联苯的浓度（6.3±2.7ng/g 脂肪，中位数 5.1ng/g 脂肪，范围 0.6-17.4ng/g 脂肪）远低于欧盟规定的 40ng/g 脂肪的最大限量。二恶英类（DL-）多氯联苯的浓度（1.7±0.7ng/g 脂肪，中位数 1.5ng/g 脂肪，范围 0.3-4.2ng/g 脂肪）和 NDL-PCBs 与 DL-PCBs 的比值（4.3）与欧盟的奶牛乳制品中的数据相似。在哈萨克斯坦骆驼奶样本中，PCBs52 和 PCB101 的比例相对较高（>60%的 6 种指示性 NDL-PCBs 之和），而在欧洲牛奶样本中，这两种物质的比例较低（<10%的 6 种指示性 NDL-PCBs 之和），这表明在哈萨克斯坦，PCBs 的暴露途径可能存在差异。在骆驼奶中，PCBs105 和 PCB118 的浓度较高（>80%的 12 种 DL-PCBs 之和）。PCBs105、PCB118 和 PCB156 是 DL-PCBs 的主要同系物，占 DL-PCBs 浓度总和的 92%（比利时奶牛为 88%）。就毒性等效浓度（TEQ）而言，PCBs126 和 PCB118 是主要的贡献者，分别占 DL-PCB TEQWHO05 浓度的 80%和 14%。无论是种族间还是地域间，NDL-和 DL-PCBs 的分布均没有明显的趋势。然而，在阿特劳地区采集的样本中，所有 DL-PCBs 的浓度似乎都明显较高。所有样本的 2,3,7,8-四氯二苯并对二恶英（TCDD）水平（平均值 0.08±0.07pg/g 脂肪，中位数 0.08pg/g 脂肪，范围 0.00-0.18pg/g 脂肪，60%>LOQs）均非常低，2,3,4,7,8-五氯二苯并呋喃（PeCDF）是 PCDD/F TEQWHO05 的主要贡献者（27%）。考虑到总 TEQWHO05（DL-PCBs 和 PCDD/Fs 的总和），DL-PCBs 和 PCDD/F 分别占 73%和 27%。当使用 TEFWHO05 量表而不是 TEFWHO98 量表时，总 TEQ 仅下降了 1%。在阿特劳地区采集的两个样本超过了欧盟规定的 6.00pg TEQWHO98/g 脂肪的最大限量值（6.4pg TEQWHO05/g 脂肪和 6.9pg TEQWHO05/g 脂肪）。这两个样本均超过了 DL-PCBs 的欧盟行动水平。由于骆驼奶被用于制备受欢迎的传统发酵饮料，如 shubat，这表明在里海地区的阿特劳，人类的暴露水平预计会高于本研究中其他地区。
