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Assessment of Dermal and Respiratory Sensitization Potential of Phthalic Anhydride and Phthalic Acid Using the GARD™skin and GARD™air Assays

Victor J. Johnson, Dori R. Germolec

DOI: https://doi.org/10.22427/NTP-DATA-500-107-001-000-4

Publication

Abstract

The purpose of this study was to use the GARD™skin and GARD™air assays to evaluate the sensitization potential of phthalic anhydride and phthalic acid to cause dermal and/or respiratory sensitization. These test compounds were nominated by the United States Environmental Protection Agency (USEPA) as part of a larger group of chemical nominations from NIEHS federal agency partners. These methods evaluate dendritic cell (DC) activation, the third key event of the skin sensitization adverse outcome pathway (AOP), which is also directly applicable to the pathogenesis of respiratory sensitization. The potential of compounds to activate DCs was assessed using a subclone of the human myeloid leukemia cell line MUTZ-3 called SenzaCell as a DC surrogate. Changes in gene expression were measured in SenzaCells following exposure to test compounds using Nanostring technology following RNA hybridization with code sets specific for dermal or respiratory sensitizers. Sensitization predictions were based on a Support Vector Machine (SVM) model that was developed using a machine learning algorithm with data collected from cell exposures to compounds with known sensitization potential. Phthalic anhydride was classified as a sensitizer in the GARDskin and GARDair assays indicating that it is a dermal and respiratory sensitizer. Phthalic acid was negative in both assays indicating that it is not a dermal or respiratory sensitizer.

Reports

Lab Report

Study Data

GARDskin Data Calculator

GARDskin GDAA Classification Report

GARDskin RCC Nanostring Files (Phthalic acid)

GARDskin RCC Nanostring Files (Phthalic anhydride)

GARDair Data Calculator

GARDair GDAA Classification Report

GARDair RCC Nanostring Files (Phthalic acid)

GARDair RCC Nanostring Files (Phthalic anhydride)