Juhasz Albert L, Tang Wayne, Smith Euan
Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia.
Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia.
Environ Res. 2016 Feb;145:145-153. doi: 10.1016/j.envres.2015.12.001. Epub 2015 Dec 14.
PAH bioaccessibility in contaminated soil was determined using the organic physiologically based extraction test with the inclusion of a sorption sink. Silicone cord was incorporated into the assay in order to overcome the limited capacity of the in vitro medium to accommodate desorbable PAHs. Initially, silicone cord sorption efficacy was determined by assessing sorption kinetics using PAH-spiked sand (phenanthrene, pyrene and benzo[a]pyrene; 10-1000mgkg(-1)). Irrespective of PAH and concentration, >95% of the initial PAH mass partitioned into the silicone cord within 12h although rates were lower at higher concentration and with increasing hydrophobicity. When PAH bioaccessibility was assessed in contaminated soil (n=18), contamination source (i.e. pyrogenic versus petrogenic) influenced PAH bioaccessibility. Individual PAH bioaccessibility ranged up to 81.7±2.7% although mean values ranged from 2.1 (acenaphthalene) to 20.8% (benzo[k]fluoranthene) with upper 95% confidence intervals of the means of 4.5 and 28.3% respectively. Although a PAH in vivo-in vitro correlation is yet to be established, bioaccessibility approaches incorporating sorption sinks represent a robust approach for estimating PAH bioavailability as the desorbable fraction may be a conservative measure of the absorbable fraction.
采用包含吸附阱的基于生理学的有机萃取试验，测定了污染土壤中多环芳烃的生物可及性。为克服体外介质容纳可解吸多环芳烃的能力有限这一问题，在试验中加入了硅胶绳。最初，通过使用添加了多环芳烃的沙子（菲、芘和苯并[a]芘；10 - 1000mgkg(-1)）评估吸附动力学，来确定硅胶绳的吸附效果。无论多环芳烃及其浓度如何，在12小时内，初始多环芳烃质量的>95%会分配到硅胶绳中，不过在较高浓度和疏水性增加时，分配速率会降低。当对污染土壤（n = 18）中的多环芳烃生物可及性进行评估时，污染源（即热解源与石油源）会影响多环芳烃的生物可及性。尽管单个多环芳烃的生物可及性最高可达81.7±2.7%，但其平均值范围为2.1%（萘）至20.8%（苯并[k]荧蒽），平均值的95%置信区间上限分别为4.5%和28.3%。虽然尚未建立多环芳烃体内 - 体外相关性，但包含吸附阱的生物可及性方法是一种估算多环芳烃生物有效性的可靠方法，因为可解吸部分可能是可吸收部分的保守量度。
