Lactational exposure to chlorinated dioxins ond related chemicals and evaluation of their toxicologicak risks to suckling

对124名分娩后2至3个月的母亲的母乳样本进行了二恶英、二苯并呋喃和其他有机氯化学物质的分析，其平均浓度和范围（括号中表示）如下：二恶英、二苯并呋喃和共面多氯联苯为2,3,7,8-二恶英；0.957ppt (0.146 ~ 2.92ppt), β - hch；17.1ppb (0.70-94.1ppb)，总滴滴涕；13.9ppb (1.03-61.4ppb)，七氯环氧化物（HCE）；0.18ppb (0.02-1.39ppb)，狄氏剂；0.17ppb (0.02-1.04ppb)，氯丹；3.22ppb （0.33-14.5ppb）和多氯联苯；十亿分之4.78磅(1.00 - -20.9)。对母乳喂养中这些化学物质的总摄入量进行了估计。出生约1年后，106名母乳喂养的婴儿也获得了血液样本，以下是本调查的主要结果。(1)母乳中二恶英、二苯并呋喃和共面多氯联苯2,3,7,8-二恶英含量与血液中cd8阳性淋巴细胞百分比呈负相关。cd4阳性淋巴细胞与cd8阳性淋巴细胞的比例随其水平的增加而增加。(2)母乳中二恶英、二苯并呋喃和共面多氯联苯2,3,7,8-二恶英含量高可显著提高血液中TSH浓度。在母乳中摄入这些化学物质的情况下，也观察到TSH水平的这种增加。(3)母乳中高浓度DDT、狄氏剂或HCE均能显著降低cd4阳性淋巴细胞的百分比，cd4阳性淋巴细胞与cd8阳性淋巴细胞之比随农药浓度的增加呈下降趋势。每种农药的估计总摄入量也对淋巴细胞亚群产生相同的影响。(4)母乳中DDT的高水平和母乳中DDT的估计总摄入量被认为显著降低了哺乳动物血液中T_4的浓度，显著增加了TSH的浓度。(5)多氯联苯对免疫系统和甲状腺激素状态的影响并不比二恶英及其相关化学物质或农药的影响强或弱。少

Breast milk samples obtained from 124 mothers at 2 to 3 months after childbirth were analyzed for dioxins, k dibenzofurans and other organochlorine chemicals and their mean concentrations and ranges, which were indicated in parentheses, were as follows : Dioxins, dibenzofurans and coplanar PCBs as 2,3,7,8-dioxin ; 0.957ppt (0.146-2.92ppt), beta-HCH ; 17.1ppb (0.70-94.1ppb), total DDT ; 13.9ppb (1.03-61.4ppb), heptachlor epoxide (HCE) ; 0.18ppb (0.02-1.39ppb), dieldrin ; 0.17ppb (0.02-1.04ppb), chlordane ; 3.22ppb (0.33-14.5ppb) and PCBs ; 4.78ppb (1.00-20.9ppb). Total intakes of these chemicals from breast-feeding were estimated.About 1 year after birth, blood samples were also obtained from 106 breast-fed babies and the following were the main results in this investigation. (1) Levels of dioxins, dibenzofurans and coplanar PCBs as 2,3,7,8-dioxin in the breast milk negatively correlated with the percentages of CD8-positive lymphocytes in the blood. Consequently, the ratios of CD4-posit … More ive to CD8-positive lymphocytes showed increasing tendency with their levels. (2) High levels of dioxins, dibenzofurans and coplanar PCBs as 2,3,7,8-dioxin in the breast milk were considered significantly enhance the concentration of TSH in the blood. This kind of increase in TSH level was also observed in case of the estimated total intake of these chemicals from the breast milk. (3) High level of DDT,dieldrin or HCE in the breast milk seemed significantly decrease the percentages of CD4-positive lymphocytes, and as a consequence, the ratio of CD4-positive to CD8-positive lymphocytes showed decreasing tendency with each level of these pesticides. Estimated total intake of each pesticide also elicited the same effects on the lymphocyte subpopulations. (4) High level in the breast milk and estimated total intake from the breast milk of DDT were considered significantly decrease the concentration of T_4 and significantly increase that of TSH in the blood of the suckling. (5) Effects of PCBs in the immune system and thyroid hormone status seemed not so strong and weaker than those of dioxins and related chemicals or the pesticides. Less