This dataset was prepared from the US Environmental Protection Agency's (EPA) Toxicity Reference Database (ToxRefDB) that contains information for 1,142 chemicals and 5,960 studies. Curations include information regarding the study design, chemical identity, dosing, treatment group parameters, treatment-related (significantly different from control) and critical (adverse) effects for all dose treatment groups, as well as endpoint testing status according to guideline specifications. ToxRefDB data was examined for all subchronic (SUB) studies with complete curations, which included registrant-submitted toxicity studies from the US EPA’s Office of Pesticide Programs (OPP) and guideline studies sourced from the National Toxicology Program (NTP).

Statistically significant differences between treatment and control group data at p<0.05 within the source documents was extracted and denoted with a “treatment-related” Boolean indicator “true”. Across the studies with absolute liver weights and relative-to-body (RLW) liver weights, the treatment-related mean effect values at the lowest effect (LE) dose levels as well as mean control liver weights were determined for all chemical-study-sex-species-exposure route groupings. The LE-ALW and LE-RLW changes were quantified as effect size differences from control using the following equation: Effect_size = 100 x (LE Effect_value – Control Effect_Value) / Control Effect_Value

Any microscopic liver pathology effects occurring at the corresponding LE dose level of weight change were also identified and listed in the dataset. Histopathology terms were presented as they appeared in ToxRefDB without harmonizing different hierarchical levels and aggregating multiple terms used to depict the same lesions. The final dataset that includes chemical stressor information, study source identifiers, study type, sex, species, strain, administration route, administration method, dose level, mg/kg/day value, qualitative and quantitative effect information, effect size from control, and pathology effects if present. The dataset includes data from 389 subchronic studies on 273 chemicals.

This dataset is associated with the following publication: Mezencev, R., M. Feshuk, L. Kolaczkowski, G. Peterson, Q. Zhao, S. Watford, and J. Weaver. The association between histopathologic effects and liver weight changes induced in mice and rats by chemical exposures: an analysis of the data from Toxicity Reference Database (ToxRefDB). TOXICOLOGICAL SCIENCES. Society of Toxicology, RESTON, VA, 200(2): 404-413, (2024).