title: Assessment of DDT relative bioavailability and bioaccessibility in historically contaminated soils using an in vivo mouse model and fed and unfed batch in vitro assays.
abstract: In this study, DDTr (DDTr = DDT + DDD + DDE) relative bioavailability in historically contaminated soils (n = 7) was assessed using an in vivo mouse model. Soils or reference materials were administered to mice daily over a 7 day exposure period with bioavailability determined using DDTr accumulation in adipose, kidney, or liver tissues. Depending on the target tissue used for its calculation, some variability in DDTr relative bioavailability was observed; however, it did not exceed 25% (range 2-25%). When DDTr bioaccessibility was determined using organic physiologically based extraction test (Org-PBET), unified BARGE method (UBM), and fed organic estimation human simulation test (FOREhST) in vitro assays, bioaccessibility was less than 4% irrespective of the assay utilized and the concentration of DDTr in the contaminated soil. Pearson correlations demonstrate a poor relationship between DDTr relative bioavailability and DDTr bioaccessibility (0.47, 0.38, and 0.28, respectively), illustrating the limitations of the static in vitro methods for predicting the dynamic processes of the mammalian digestive system for this hydrophobic organic contaminant.
authors.affiliation: Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia. Euan.Smith@unisa.edu.au
authors.forename: Euan
authors.initials: E
authors.lastname: Smith
authors.forename: John
authors.initials: J
authors.lastname: Weber
authors.forename: Allan
authors.initials: A
authors.lastname: Rofe
authors.forename: Dorota
authors.initials: D
authors.lastname: Gancarz
authors.forename: Ravi
authors.initials: R
authors.lastname: Naidu
authors.forename: Albert L
authors.initials: AL
authors.lastname: Juhasz
mesh_terms: D000538:Aluminum Silicates / Q000032:analysis; D000818:Animals; D001681:Biological Assay / Q000379:methods*; D001682:Biological Availability; D000077215:Clay; D003634:DDT / Q000737:chemistry / Q000378:metabolism*; D004784:Environmental Monitoring; D006801:Humans; D051379:Mice; D023421:Models, Animal; D009928:Organ Specificity; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000538:Aluminum Silicates; D012987:Soil; D012989:Soil Pollutants; D003634:DDT; D000077215:Clay