Blanck H M, Marcus M, Hertzberg V, Tolbert P E, Rubin C, Henderson A K, Zhang R H
Biological and Biomedical Sciences Division, Nutrition and Health Sciences Program, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Environ Health Perspect. 2000 Feb;108(2):147-52. doi: 10.1289/ehp.00108147.
Accidental contamination of the food chain in Michigan in 1973 with polybrominated biphenyls (PBBs) led to the establishment of a registry of exposed individuals in 1976. Serum was collected and analyzed for PBB at the time of enrollment and for targeted studies in the following years. We used the archived PBB data to study the elimination of PBB and to identify factors associated with elimination. A total of 380 women >= 16 years of age who had an initial PBB level of 2 ppb and at least two serum samples drawn when they were not pregnant were included in the analysis. The mean initial PBB level was 20.9 ppb (median 4) and mean time between the first and last measurement was 4.2 years (range 0.5-11.1). PBB was assumed to reach equilibrium in the body before substantial amounts were eliminated and before the first serum measurements were taken; therefore, the entire body was modeled as a single compartment for PBB with exponential decay. Subject-specific decay rate estimates were regressed on predictor variables including initial age, body mass index (BMI), smoking history, breast-feeding duration, and parity. In women with an initial PBB level < 10 ppb, the median half-life was 12.9 years; in those with > 10 ppb, the median half-life was 28.7 years. Decay was significantly slower among women with an initial BMI at or above the median (BMI >= 23). The calculated half-life values are estimates of decay and can be used to estimate body burden of PBB at various points in time other than at the time of serum collection.
1973年，密歇根州的食物链意外受到多溴联苯（PBBs）污染，这促使在1976年建立了一个暴露个体登记册。在登记时收集血清并分析其中的多溴联苯，在随后几年进行针对性研究。我们利用存档的多溴联苯数据来研究其消除情况，并确定与消除相关的因素。共有380名年龄≥16岁、初始多溴联苯水平为2 ppb且在非孕期至少采集过两份血清样本的女性纳入分析。初始多溴联苯的平均水平为20.9 ppb（中位数为4），首次和末次测量之间的平均时间为4.2年（范围为0.5 - 11.1年）。假定多溴联苯在体内大量消除之前以及首次血清测量之前已达到平衡；因此，将整个身体建模为一个多溴联苯呈指数衰减的单室模型。将个体特异性衰减率估计值对包括初始年龄、体重指数（BMI）、吸烟史、母乳喂养持续时间和产次等预测变量进行回归分析。初始多溴联苯水平<10 ppb的女性，中位数半衰期为12.9年；初始多溴联苯水平>10 ppb的女性，中位数半衰期为28.7年。初始BMI处于或高于中位数（BMI≥23）的女性中，衰减明显较慢。计算出的半衰期值是衰减的估计值，可用于估计血清采集时间以外不同时间点的多溴联苯身体负担。
