Assessment of the bioaccessibility of polycyclic aromatic hydrocarbons in topsoils from different urban functional areas using an in vitro gastrointestinal test

Abstract

Profiles of the bioaccessibility of soil polycyclic aromatic hydrocarbons (PAHs) in different urban functional areas of Xiamen City, Fujian, China were investigated. A physiologically based in vitro test was used to evaluate the bioaccessibility of total and individual PAHs. There was no obvious correlation between total concentrations of PAHs and bioaccessibility during the gastrointestinal phase for the soils from different functional areas. Results showed that the bioaccessibility variation in the gastrointestinal phase (ranging from 14.6% to 63.2%) was significantly higher than that in the gastric phase (ranging from 4.9% to 21.8%). The bioaccessibility in the gastrointestinal phase was not only determined by soil organic materials but also directly related to physical and chemical properties of individual PAHs, except for two-ring PAHs. Increasing soil organic material content or decreasing ring numbers of PAHs could result in the decrease of PAH bioaccessibility. The total PAH bioaccessibility was largely contributed by individual PAHs with relatively high molecular weight.

Optimization of an in vitro method to measure the bioaccessibility of polybrominated diphenyl ethers in dust using response surface methodology

“…The concentrations of PBDEs in the dust sample from the filter of the air conditioner were much higher than those in the other three samples, but the bioaccessibility of PBDEs in this dust sample showed little difference from the other three samples, indicating that PBDE concentrations did not affect the bioaccessibility of PBDEs in dust. The observation was similar to those in the studies on PAHs and PCBs in soil (Oomen et al, 2000;Khan et al, 2008;Lu et al, 2010). In addition, there was no significant difference between our results and those obtained with the NIST SRM 2585 dust (Huwe et al, 2008;Lepom et al, 2010), demonstrating that dust itself might not be an issue in the determination of the bioaccessibility of PBDEs.…”

“…1c, e, f). Similar results were reported on polychlorinated biphenyls (PCBs) and PAHs in soil (Oomen et al, 2000;Khan et al, 2008;Lu et al, 2010). It was not surprising because the partitioning of a hydrophobic organic compound (HOC) between the solid and liquid phases was a constant at given conditions.…”

Impact of reference geosorbents on oral bioaccessibility of PAH in a human in vitro digestive tract model

“…The increased mobilization of high molecular weight PAH may result from the formation of mixed micelles in bile (Oomen et al 2004) that enhances water solubility of poorly soluble PAH. In former studies, increasing PAH bioaccessibility with increasing ring number was only found by Lu et al (2010) and van de Wiele et al (2004) and requires further investigation.…”

“…Former studies on soil samples suggested soil organic carbon (SOC) to be one reason for variable PAH bioaccessibility (Hack and Selenka 1996;Lu et al 2010;Pu et al 2004;Tao et al 2010;Vasiluk et al 2007). Grøn et al (2007) and Hansen et al (2007) estimated maximum bioaccessibility (25-40 %) at lowest "humic content" (2 %) and lower bioaccessibility (6-24 %) at 4-5 % "humic content."…”

Function of Nitrate Ion and Tea Saponin Application Rates in Anerobic PAH Dissipation in Paddy Soil

“…Low PAH bioaccessibility including mass transfer limitations of PAHs (especially those with high molecular weight) from several matrices into the aqueous phase for effective enzyme-based microbial biodegradation still constitutes a major challenge for aged contaminated soils [11]. Various surfactants and solubility enhancers enhanced PAH bioaccessibility and biodegradation [12,13].…”