Environmental and Molecular Toxicology Department, Oregon State University , ALS 1007, Corvallis, Oregon 97331, United States.
Environ Sci Technol. 2014 Jun 3;48(11):6291-9. doi: 10.1021/es5000534. Epub 2014 May 19.
The current work sought to develop predictive models between time-weighted average polycyclic aromatic hydrocarbon (PAH) concentrations in the freely dissolved phase and those present in resident aquatic organisms. We deployed semipermeable membrane passive sampling devices (SPMDs) and collected resident crayfish (Pacifastacus leniusculus) at nine locations within and outside of the Portland Harbor Superfund Mega-site in Portland, OR. Study results show that crayfish and aqueous phase samples collected within the Mega-site had PAH profiles enriched in high molecular weight PAHs and that freely dissolved PAH profiles tended to be more populated by low molecular weight PAHs compared to crayfish tissues. Results also show that of several modeling approaches, a two-factor partial least-squares (PLS) calibration model using detection limit substitution provided the best predictive power for estimating PAH concentrations in crayfish, where the model explained ≥72% of the variation in the data set and provided predictions within ∼3× of measured values. Importantly, PLS calibration provided a means to estimate PAH concentrations in tissues when concentrations were below detection in the freely dissolved phase. The impact of measurements below detection limits is discussed.
当前的工作旨在建立时间加权平均多环芳烃（PAH）在自由溶解相和存在于居留水生生物中的浓度之间的预测模型。我们在俄勒冈州波特兰市的波特兰港超级基金 mega-site 内外的九个地点部署了半渗透膜被动采样器（SPMD）并收集了居留小龙虾（Pacifastacus leniusculus）。研究结果表明，在 mega-site 内采集的小龙虾和水相样本中富含高分子重量的 PAH 分布，而自由溶解的 PAH 分布则倾向于含有更多的低分子量 PAHs，与小龙虾组织相比。结果还表明，在几种建模方法中，使用检出限替代的双因素偏最小二乘法（PLS）校准模型提供了对小龙虾中 PAH 浓度的最佳预测能力，该模型解释了数据集的变化的≥72%，并提供了测量值的约 3×范围内的预测值。重要的是，PLS 校准提供了一种方法，可以在自由溶解相中浓度低于检出限的情况下估计组织中的 PAH 浓度。讨论了低于检出限的测量值的影响。
