Application of the Pollutants-FCNN Framework:A Multi-Task Neural Network Approach for Con-taminant Toxicity Prediction Based on Tox21Data
Abstract
Contaminant toxicity prediction is a pivotal technology for environmental risk assessment and chemical safety management, but traditional experimental methods are limited by high resource consumption, prolonged test cycles, and ethical controversies related to animal experimentation. This study proposes the Pollutants-FCNN Framework, a multi-task learning-based neural network architecture integrated with a multi-head attention mechanism, dedicated to predicting four major toxicity types (biological toxicity, cell toxicity, neurotoxicity, genotoxicity) using the Tox21 benchmark dataset. The framework processes 801 dimensional chemical feature vectors through a standardized pipeline including data preprocessing, attention-augmented FCNN modeling, and multi-task optimization. All core mathematical formulations are derived from the framework’s implementation code to ensure consistency between theoretical design and practical application. Experimental validation shows that the Pollutants-FCNN Framework outperforms conventional pure FCNN models and single-task learning paradigms, achieving a macro-average Area Under the ROC Curve (AUC) of 0.789. This method provides an efficient and reliable in silico toxicity assessment tool, resolving key challenges such as data scarcity for specific endpoints and inefficient feature interaction capture in toxicological modeling. The framework’s modular design and reproducible protocol make it suitable for application in environmental risk assessment and chemical safety screening.
1. Integrates multi-task learning and multi-head attention mechanism to address core challenges of data scarcity and inefficient feature interaction capture in toxicological modeling.
2. Achieves a macro-average AUC of 0.789 on the Tox21 dataset, outperforming traditional pure FCNN and single-task learning models.
3. Features modular design and reproducible protocol, which is applicable to environmental risk assessment and chemical safety screening scenarios.
Keywords:
Contaminant Toxicity Prediction; Multi-Task Neural Network; Multi-Head Attention; Feedforward Neural Network(FCNN); Tox21 DatasetData Availability Statement
The data used in this study are derived from the publicly available Tox21 dataset released by the U.S. Environmental Protection Agency (EPA) and the National Institutes of Health (NIH). Additional data and code supporting the findings of this study are available from the corresponding author upon reasonable request.
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