Designing QSARs for Parameters of High-Throughput Toxicokinetic Models Using Open-Source Descriptors

Autor: Brandall Ingle, John F. Wambaugh, Daniel E. Dawson, Katherine Phillips, Rogelio Tornero-Velez, John W. Nichols
Rok vydání: 2021
Předmět:
Zdroj: Environ Sci Technol
ISSN: 1520-5851
Popis: The intrinsic metabolic clearance rate (Cl(int)) and fraction of chemical unbound in plasma (f(up)) serve as important parameters for high throughput toxicokinetic models, but experimental data are limited for many chemicals. Open-source quantitative structure-activity relationship (QSAR) models for both parameters were developed to offer reliable in silico predictions for a diverse set of chemicals regulated under U.S. law, including pharmaceuticals, pesticides, and industrial chemicals. As a case study to demonstrate their utility, model predictions served as inputs to the TK component of a risk-based prioritization approach based on Bioactivity: Exposure Ratios (BER), in which a BER < 1 indicates exposures are predicted to exceed a biological activity threshold. When applied to a subset of the Tox21 screening library (6484 chemicals) we found that the proportion of chemicals with BER 1 using either in silico or in vitro parameters (768/848, 90.5%). Thus, the presented QSARs may be suitable for prioritizing the risk posed by many chemicals for which measured in vitro TK data are lacking.
Databáze: OpenAIRE