Implementation of animal-free chemical safety assessment algorithms

Fraunhofer ITEM and the ASPIS cluster are collaborating to deploy the Alternative Safety Profiling Algorithm workflow for chemical risk analysis. This technical integration focuses on utilizing in vitro methods and computational models to replace animal testing in regulatory safety assessments.

Operational Challenges and Collaboration
Regulatory authorities and chemical industries face the structural challenge of assessing chemical safety while phasing out animal testing. To address these requirements and comply with the European Commission roadmap, Fraunhofer ITEM partners with the EU-funded RISK-HUNT3R project and the ASPIS cluster. This cooperation integrates toxicological expertise with new approach methodologies to develop standardized, animal-free evaluation workflows for industrial and pharmaceutical applications.

Technical Solution and Responsibilities
The technical architecture is based on the Alternative Safety Profiling Algorithm, which comprises approximately 55 modular assessment elements. Fraunhofer ITEM develops physiologically based kinetic models that translate biological processes into mathematical equations, simulating human absorption, distribution, metabolism, and excretion based on substance-specific parameters. The ASPIS cluster provides the structural framework, combining high-throughput in vitro assays with machine learning methods to calculate systemic toxicity. The integrated ASPA-assist software is utilized to guide users through the evaluation steps and document interim decisions for regulatory transparency.

Deployment and Implementation
The deployment of these assessment models occurs within regulatory testing frameworks and specific case studies, such as the OECD integrated approaches to testing and assessment. During the implementation phase, researchers utilize extensive omics data to characterize the biological activity profiles of airborne substances, gases, and liquid aerosols. The kinetic models are applied to convert doses measured in laboratory environments into realistic exposure scenarios within the human body.

Applications and Use Cases
This predictive technology is applied directly to the safety assessment of chemicals, pharmaceuticals, and inhalable substances. The functional use cases involve prioritizing chemical compounds based on potential systemic toxicity and executing risk analyses using data-driven read-across methods. Applying this modular algorithm stabilizes the regulatory evaluation process and eliminates the dependency on conventional animal testing methodologies by utilizing human-relevant cellular test systems.

Results and Expected Impact
The integration of the assessment workflow provides a reproducible method for calculating chemical risks while continuously assessing uncertainties. Formalizing these evaluation procedures facilitates regulatory acceptance and integration into European safety processes. Regarding the system architecture, Sylvia Escher, research scientist at Fraunhofer ITEM, explains: "The ASPA workflow is a transparent, reproducible and modular approach to animal-free Next Generation Risk Assessment of chemicals". She further details the data integration process: "With ASPA, we transparently integrate biological activity data from a range of new approach methodologies (NAMs), information on human uptake and exposure, and toxicological mechanisms".

Edited by Maria Brueva, Induportals editor – adapted by AI.

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