In vivo measurement, in vitro estimation and fugacity prediction of PAH bioavailability in post-remediated creosote-contaminated soil

Abstract

In this study, PAH bioavailability was assessed in creosote-contaminated soil following bioremediation in order to determine potential human health exposure to residual PAHs from incidental soil ingestion. Following 1,000 days of enhanced natural attenuation (ENA), a residual PAH concentration of 871 ± 8 mg kg(-1) (∑16 USEPA priority PAHs in the <250 μm soil particle size fraction) was present in the soil. However, when bioavailability was assessed to elucidate potential human exposure using an in vivo mouse model, the upper-bound estimates of PAH absolute bioavailability were in excess of 65% irrespective of the molecular weight of the PAH. These results indicate that a significant proportion of the residual PAH fraction following ENA may be available for absorption following soil ingestion. In contrast, when PAH bioavailability was estimated/predicted using an in vitro surrogate assay (FOREhST assay) and fugacity modelling, PAH bioavailability was up to 2000 times lower compared to measured in vivo values depending on the methodology used.

‘Towards a unified approach for the determination of the bioaccessibility of organic pollutants’

“…Differences in soil properties, particularly organic content, and the physicochemical properties of the analytes were cited as reasons for variation within the test. When compared with in-vivo tests the FOREhST model underestimated the bioavailability of the pesticide DDT in a mouse model by 3-15 fold , it also under predicted the bioavailability of PAHs in soil by 50 fold (Juhasz et al, 2014).…”

Estimating the bioavailability of trace metals/metalloids and persistent organic substances in terrestrial environments: challenges and need for multidisciplinary approaches

“…Correlations between oral bioaccessibility (in vitro tests) and oral bioavailability (in vivo tests) of organic substances in soil have been discussed for ten years [33,34]. Recently, in vivo measurements using a mouse model have been compared to in vitro estimation and fugacity prediction of PAH bioavailability in post-remediated creosote-contaminated soils [35]. In this case PAH bioavailability assessed by an in vitro surrogate assay (FOREhST assay) and fugacity modeling was up to 2000 times lower than measured in vivo values depending on the methodology used [35].…”

“…Recently, in vivo measurements using a mouse model have been compared to in vitro estimation and fugacity prediction of PAH bioavailability in post-remediated creosote-contaminated soils [35]. In this case PAH bioavailability assessed by an in vitro surrogate assay (FOREhST assay) and fugacity modeling was up to 2000 times lower than measured in vivo values depending on the methodology used [35]. DDT bioaccessibility measured using organic physiologically based extraction test (Org-PBET), unified BARGE method (UBM), and fed organic estimation human simulation test (FOREhST) in vitro assays was compared to data obtained using an in vivo mouse model (accumulation of administered DDT in adipose, kidney, or liver tissues) [36].…”

Toxic Pollutants in China

“…Phenanthrene, CAS#85-01-8, is a priority PAHs and 1 Development of Water Quality Criteria … has been shown to have high toxicity to marine diatoms, gastropods, mussels, crustaceans, and fish (Zhang et al 2014). Phenanthrene (PHE) has been detected in surface water worldwide in recent years, and it has already become the subject of various scientific fields (Callen et al 2013;Juhasz et al 2014;Qiao et al 2006). Previous studies showed that PHE is toxic to aquatic organisms (Meier et al 2013;, so it may impose risks to the ambient aquatic environment.…”