Development and verification of a toxicokinetic model of polychlorinated biphenyl elimination in persons working in a contaminated building

详细信息    查看全文

• 作者：Horst Christoph Broding ; Thomas Schettgen ; Thomas Gö ; en ; Jü ; rgen Angerer ; Hans Drexler
• 关键词：PCB congeners ; Occupational hazards ; Biological monitoring ; Toxicokinetic modeling ; Half-life
• 刊名：Chemosphere
• 出版年：2007
• 出版时间：July 2007
• 年：2007
• 卷：68
• 期：8
• 页码：1427-1434
• 全文大小：303 K

文摘

Background

Polychlorinated biphenyls are toxic and slowly degrading substances that have been in widespread industrial use in the 1960s and 1970s. Despite a worldwide reduction, environmental exposure remains an issue; the assessment of an individual’s level of exposure at a given time in retrospect requires valid toxicokinetic modeling of the different PCB congeners.

Objectives

To develop and verify a toxicokinetic model of the in vivo-degradation of PCB 28 and 52 in adult humans.

Methods

The plasma concentrations of PCB congeners were measured in 583 persons working in a contaminated building for an average of 14.7 ± 9.6 years. The values were adapted to a simple pharmacokinetic model (y_t = y₀ × (1 − e^−kt)); the steady state concentration y₀ was estimated based on the median values of persons working exposed more than 10 years.

Results

The steady state concentration of PCB 28 was 0.10 μg/l, that of PCB 52 0.02 μg/l. The half-life of the congeners was estimated based on a logarithmic regression analysis according to the model mentioned above; it was 2.18 (95 % CI: 1.91–2.54) years for PCB 28 and 3.95 (95 % CI: 3.55–4.45) years for PCB 52, respectively. Stepwise elimination of persons with very long employment duration did not reduce the estimated half-life.

Conclusions

The estimated half-life is higher than previously published data especially for PCB 52. Possible reasons and implications of this finding are discussed.