Oral relative bioavailability of Dichlorodiphenyltrichloroethane (DDT) in contaminated soil and its prediction using in vitro strategies for exposure refinement

Journal Article · Sat Oct 15 04:00:00 EDT 2016 · Environmental Research

DOI:https://doi.org/10.1016/J.ENVRES.2016.06.039· OSTI ID:22689495

Herde, Paul ^[1]; Smith, Euan ^[2]

---

1. South Australian Health and Medical Research Institute, Gilles Plains, SA 5086 (Australia)
2. Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095 (Australia)

In this study, the bioavailability of DDTr (sum of DDT, DDD and DDE isomers) in pesticide-contaminated soil was assessed using an in vivo mouse model. DDTr relative bioavailability (RBA) ranged from 18.7±0.9 (As35) to 60.8±7.8% (As36) indicating that a significant portion of soil-bound DDTr was not available for absorption following ingestion. When DDTr bioaccessibility was assessed using the organic Physiologically Based Extraction Test (org-PBET), the inclusion of a sorption sink (silicone cord) enhanced DDTr desorption by up to 20-fold (1.6–3.8% versus 18.9–56.3%) compared to DDTr partitioning into gastrointestinal fluid alone. Enhanced desorption occurred as a result of the silicone cord acting as a reservoir for solubilized DDTr to partition into, thereby creating a flux for further desorption until equilibrium was achieved. When the relationship between in vivo and in vitro data was assessed, a strong correlation was observed between the mouse bioassay and the org-PBET+silicone cord (slope=0.94, y-intercept=3.5, r{sup 2}=0.72) suggesting that the in vitro approach may provide a robust surrogate measure for the prediction of DDTr RBA in contaminated soil. - Highlights: • An optimised mouse assay was used to quantify DDTr relative bioavailability in soil. • DDTr bioaccessibility was also determined using an in vitro sorption sink approach. • A strong correlation was observed between in vivo and in vitro data. • The sorption sink approach may be used to predict DDTr relative bioavailability.

• OSTI ID: 22689495
• Journal Information: Environmental Research, Journal Name: Environmental Research Vol. 150; ISSN ENVRAL; ISSN 0013-9351
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
BIOASSAY
BIOLOGICAL AVAILABILITY
COMPARATIVE EVALUATIONS
DDT
IN VITRO