大连地区唐氏筛查孕中期妇女羊水中甲状腺激素水平与PBDEs内暴露关系初探

多溴联苯醚(polybrominated diphenyl ethers,PBDEs)是一类常用的溴代阻燃剂,由于使用广泛,已成为普遍存在的环境污染物。研究表明,PBDEs具有内分泌干扰作用,影响甲状腺功能,对胚胎发育、婴幼儿及儿童的健康存在潜在的危害。本研究采集了100例具羊水穿刺指征的孕妇的孕中期羊水样本,采用罗氏全自动电化学发光免疫分析仪测定羊水中促甲状腺激素(TSH)、三碘甲状腺原氨酸(TT3)、游离三碘甲状腺原氨酸(FT3)、甲状腺素(TT4)、游离甲状腺素(FT4)、抗甲状腺过氧化酶抗体(TPOA)和抗甲状腺球蛋白抗体(TGA)的含量,用气相色谱-负化学源-质谱法测定羊水样品中16种PBDEs同系物含量。结果显示,羊水中TSH、TT3、FT3、TT4、FT4中位数分别为0.342μIU·m L-1、0.949 nmol·L-1、1.52 pmol·L-1、11.02 nmol·L-1和3.91pmol·L-1,95%参考区间值分别为0.174~0.872μIU·m L-1、0.835~1.01 nmol·L-1、1.26~2.72 pmol·L-1、9.42~20.68 nmol·L-1和2.16~6.35 pmol·L-1。具有唐氏筛查高风险和甲状腺激素水平低下的羊水样品中共检出6种BDEs(BDE-47、BDE-71、BDE-138、BDE-183、BDE-190、BDE-209),其中BDE-71、183和190在被检羊水样品中均被检出,并且,TSH水平低下的羊水中BDE-190和209负荷水平显著高于正常组。这些结果提示,大连地区孕中期妇女羊水存在PBEDs内暴露,并且PBDEs内暴露可能与羊水的甲状腺激素水平低下、尤其TSH水平升高有关,提示PBDEs暴露可能与胎儿中枢神经系统损伤产生的下丘脑-垂体-甲状腺(HPT)轴功能失调有关。因此,羊水PBDEs内暴露对新生儿出生结局的影响值得进一步关注。

Evaluation of Maternal PBDEs Exposure on the Thyroid Hormones in Amniotic Fluid of the Women Undergoing Amniocentesis at Late Second Trimester of Pregnancy in Dalian City

Polybrominated diphenyl ethers (PBDEs) have been widely used as flame retardants for several decades leading to high levels of presence in the environmental media and frequent detection in biological specimens.It has been well documented that PBDEs can disrupt the endocrine system,and by interfering the thyroid hormones,they pose harmful effects on fetal development resulting in adverse health problems in offspring.The current study recruited 100 women who were at the mid-stage of pregnancy and undergoing amniocentesis.We collected their amniotic fluid samples.The levels of thyroid hormones in amniotic fluid were analyzed by Roche automatic electrochemiluminescence immunoassay analyzer,including thyroid stimulating hormone (TSH),total triiodothyronine (TT3),free triiodothyronine (FT3),total thyroxine (TT4),free thyroxine (FT4),thyroid peroxidase antibody (TPOA) and thyroglobulin antibody (TGA),and the levels of PBDEs in amniotic fluid were detected using the GCNCI-MS.To summarize,the median and reference interval (RI) were calculated for each of TSH (0.342 μIU·mL-1,95％ RI:0.174-0.872 μIU·mL-1),TT3 (0.949 nmol·L-1,95％ RI:0.835-1.01 nmol·L-1),FT3 (1.52 pmol· L-1,95％ RI:1.26-2.72 pmol·L-1),TT4 (11.02 nmol·L-1,95％ RI:9.42-20.68 nmol·L-1) and FT4 (3.91 pmol· L-1,95％ RI:2.16-6.35 pmol· L-1) by the non-parametric method.A subset of amniotic fluid samples,based on the selection criteria of Down syndrome high risk and/or thyroid hormone deficiency,was assessed on the levels of 16 PBDE congeners.The correlation between the levels of PBDEs and the risks for thyroid hormone deficiency and Down syndrome was examined.Among 16 PBDE congeners,6 (BDE-47,71,138,183,190 and BDE-209) were detected in the amniotic fluid samples of three groups,and among them,3 (BDE-71,183 and 190) were found in all 3 groups.While the high levels of BDE-190 and 209 exposure were not suggested for high risk of Down syndrome,the correlation between the levels of BDE-190 and 209 in amniotic fluid and high risk of low TSH in amniotic fluid was established.Our data indicate that maternal exposure to PBDEs during early pregnancy may place developing fetuses in high risks of neuronal injuries and resultant disruption on hypothalamic-pituitary-thyroid (HPT) axis and adverse outcomes in newborns.