Measurements of octanol-air partition coefficients (KOA) for polybrominated diphenyl ethers (PBDEs):: Predicting partitioning in the environment
Measurements of octanol-air partition coefficients (KOA) for polybrominated diphenyl ethers (PBDEs):: Predicting partitioning in the environment
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DOI：
10.1021/je010192t
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发表时间：
2002-03-01
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影响因子：
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通讯作者：
Shoeib, M
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文献类型：
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作者：
Harner, T;Shoeib, M
报告了13种多溴二苯醚在15-45 ℃温度范围内的辛醇-空气分配系数。K-OA与绝对温度呈对数线性关系，25 ℃时的数值范围为9.3（PBDE-17）至12.0（PBDE-126）。这比对应的多氯联苯（PCB）测量值大约高出1至2个数量级。多溴二苯醚还表现出强烈的温度依赖性。从辛醇到空气的相变焓Δ H（OA）为（约70 ~约120）kJ mol（-1）。这对应于在5 ℃下比在35 ℃下高20-100倍的K-OA值。本文提出了一种利用相对保留时间估算其他多溴二苯醚在任何温度下的K-OA的方法。将Log KOA值与两组最近公布的过冷液体蒸气压（p度（L））进行比较，结果显示存在显著差异。当使用一组蒸气压时，多溴二苯醚在辛醇中的活度系数（y（O））为1至10。这与其他类别的SOC一致，表明接近理想的溶液行为。当使用第二组值时，计算的活度系数在10-100的范围内，表明这些蒸气压值不准确。还研究了K-OA在描述多溴联苯醚在气溶胶和土壤中分配方面的应用。气溶胶的预测百分比（25摄氏度）从PBDE-17的1.2%到PBDE-183的85%不等，与测量数据吻合良好，证实了地表-空气分离是多溴二苯醚在环境中分布和归宿的一个重要过程。对空气-土壤分配的说明性计算结果表明，由于多溴二苯醚的K-OA值较高，尽管其在空气中的浓度要低得多，但其在土壤中的背景浓度与多氯联苯相似。
Octanol-air partition coefficients (K-OA) are reported for 13 polybrominated diphenyl ethers (PBDEs) over the temperature range (15-45) degreesC. K-OA exhibited a log-linear relationship with inverse absolute temperature, and values at 25 degreesC range from 9.3 (PBDE-17) to 12.0 (PBDE-126). These are approximately 1 to 2 orders of magnitude greater than those measured for the counterpart polychlorinated biphenyls (PCBs). PBDEs also showed a strong temperature dependence. The enthalpy of phase change from octanol to air, DeltaH(OA), was (approximate to70 to approximate to 120) kJ mol(-1). This corresponds to a 20-100 times higher K-OA value at 5 degreesC versus 35 degreesC. A method is presented for estimating K-OA at any temperature for additional PBDEs using relative retention times. Log KOA values were compared against two sets of recently published subcooled liquid vapor pressures (pdegrees(L)) that show significant discrepancies. Activity coefficients in octanol (y(O)) for PBDEs ranged from 1 to 10 when one set of vapor pressures was used. This was consistent with other classes of SOCs and indicated near ideal solution behavior. When the second set of values was used, calculated activity coefficients were in the range 10-100, suggesting that these vapor pressure values were inaccurate. Application of K-OA for describing partitioning of PBDEs to aerosols and soils was also examined. The predicted percentages (at 25 degreesC) on aerosols ranged from 1.2% for PBDE-17 to 85% for PBDE-183 and agreed well with measured data, confirming that surface-air partitioning is an important process for the distribution and fate of PBDEs in the environment. Results of illustrative calculations for air-soil partitioning suggest that, because of their high K-OA values, PBDEs will exhibit similar background soil concentrations as the PCBs despite having much lower air concentrations.