中文摘要：

用体外模拟方法研究了土壤中多环芳烃在消化过程中的释放,并验证了如下假设：消化过程释放出来的多环芳烃部分吸着在消化残渣相中,且该吸着可以影响多环芳烃生物可给性测定结果.研究结果表明,经消化释放出来的多环芳烃可以部分吸着在消化固相残渣中.就有机碳含量从2.87%到0.63%的四种土壤中的平均情况而言,多环芳烃残余固相上的吸着量占总可给态量的比率分别为：43.6%±14.3%（二氢苊）,29.8%±24.6%（苊）,43.1%±22.9%（芴）,34.1%±25.8%（菲）,14.0%±16.2%（蒽）,25.2%±15.9%（荧蒽）,33.4%±23.1%（芘）,30.7%±26.6%（苯并蒽）和29.1%±23.4%（■）.显然,忽略吸着现象将显著低估实际消化率.如果对吸着进行定量校正,则总多环芳烃的消化率分别从校正前的18.9%,12.2%,22.8%和33.4%增长到29.0%,29.3%,41.9%和37.6%,提升幅度在4.21%到10.1%之间.

英文摘要：

An in vitro model was used to simulate gastrointestinal digestion so as to determine bioaccessibility of polycyclic aromatic hydrocarbons （PAHs） in soil. Four surface soil samples with various levels of contamination and organic matter contents were collected for the experiment without further spiking. The hypothesis to be tested is that a fraction of PAHs mobilized during the digestion may be sobbed on the solid phase leading to an underestimation of the digestion coefficients. The hypothesis was confirmed experimentally and it was demonstrated that there was significant influence of the sorption on the results. Such an influence and the underestimation can be corrected by a multiple soil/fluid ratios experimental design. The percentages of PAHs sobbed were 43.6% ± 14. 3% （acenaphthene）, 29. 8% ±24. 6% （acenaphthylene）, 43.1% ±22.9% （fluorene 34. 1% ± 25. 8% （ phenanthrene）, 14. 0% ± 16. 2% （ anthracene ）, 25.2% ± 15.9% （ fluoranthene 33.4% ±23.1% （pyrene）, 30.7% ±26.6% （benz（a）anthracene） and 29.1% ±23.4% （chrysene ）, ）, respectively. For the total PAHs, the digestion coefficients were 18.9%, 12. 2%, 22. 8% and 33.4% without correction and 29.0%, 29.3%, 41.9% and 37.6% with correction for the four soil samples with various organic carbon contents, respectively.