Analysis of the Performance of the GHS Mixtures Equation to Predict Acute Oral Toxicity of Formulations

The majority of pesticide registration applications require product-specific acute toxicity data. Thus, an alternative to in vivo testing for this purpose could greatly reduce animal testing. However, predicting toxicity using NAMs is challenging for mixtures such as pesticides. The GHS Mixtures Equation estimates the acute toxicity of mixtures using the toxicities of mixture components. EPA and NIEHS scientists conducted a study (Hamm et al. 2021) to evaluate the concordance of hazard classifications predicted using the GHS Mixtures Equation with classifications based on in vivo test results. The results of the analysis suggested that the GHS Mixtures Equation can help predict the acute oral toxicity of mixtures, particularly those with lower toxicity.