Experimental evaluation and mathematical modeling of combined cytotoxicity of lead and copper in vitro on IMR-32 neuroblastoma cells

Introduction. Modern industrial enterprises are noted for pollution of the workplace air with a multicomponent mixture of chemicals, the combined exposure to which can significantly differ from their isolated ones and have a different toxic effect. Experimental studies and mathematical modeling of combined effects of toxic metals on various systems and organs are the scientific basis for assessing both occupational and environmental risks.

The purpose of the research was to study the combined toxicity of lead and copper in an in vitro experiment using mathematical modeling.

Material and methods. Experimental studies were carried out on an in vitro model using the IMR-32 cell line. Cytotoxicity was established following exposure to soluble lead and copper salts by measuring dehydrogenase activity using the MTT assay.

Results. We have demonstrated that, in terms of dehydrogenase activity, the type of the combined effect of lead and copper in IMR-32 neuroblastoma cells changes with the increase in concentrations of the toxicants. At low doses of copper and lead, the type of combined action is additive, but with increasing doses it becomes antagonistic.

Limitations. To assess the effect of lead and copper on cell culture, estimates calculated from one measured parameter of the dehydrogenase activity were used.

Conclusion. Our findings support the general theory of combined toxicity, postulating the ambiguousness of the type of effect exhibited by the same pair of agents.

Compliance with ethical standards. The study does not require the submission of the conclusion of the biomedical ethics committee and other documents.

Authors’ contribution:
Minigalieva I.A., Sutunkova M.P. – concept and design of research, editing;
Shabardina L.V. – collection of material, data processing, writing;
Panov V.G. – data processing, statistical analysis;
Bushueva T.V., Karpova E.P. – collection of material and data processing.
All co-authors are responsible for approving the final version of the article and ensuring the integrity of all its parts.

Conflict of interest. The authors declare no apparent and potential conflicts of interest in relation to the publication of this article.

Funding. The study had no sponsorship.

Received: March 3, 2025 / Revised: April 4, 2025 / Accepted: November 25, 2025 / Published: January 15, 2026

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