EPA-generated data used for basis of modelling in "Challenging Additivity: Comparing Predicted and Observed AhR Activity of PAC Mixtures with Active and Inactive Constituents". This dataset is associated with the following publication: Eccles, K., K. Gaston, E. Green, S. Waidyanatha, B. Stiffler, S. Harris, C. Rider, and E. Medlock Kakaley. In vitro assessment of known environmental contaminants and mixtures to determine in vivo relevance. ENVIRONMENT INTERNATIONAL. Elsevier B.V., Amsterdam, NETHERLANDS, 2976-2987, (2026).