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ICCVAM Biennial Report 2018-2019

Biennial Progress Report 2018-2019 Interagency Coordinating Committee on the Validation of Alternative Methods

Unsupervised Data-driven Analysis of Tox21 Assay Data

Scientists at NIEHS are using computational data organization methods based on patterns to identify chemicals that exhibit biological properties similar to those of well-characterized toxicants in the Tox21 10K library. Users will soon be able to perform bioactivity-based correlations to compare query chemicals with well-characterized Tox21 toxicants using the Tox21 Correlation Browser. An upgrade to the Correlation Browser is in progress and an improved web tool will be available in 2020.

Results of these analyses are being used in combination with another tool, Tox21 Enricher, to help prioritize compounds for more extensive toxicological testing. The Tox21 Enricher performs neighborhood enrichment analysis to determine if one or more input chemicals have characteristics that show similar bioactivity patterns to characterized chemicals. Tox21 Enricher has been described in a publication (Hur et al. 2018).