Comparative assessment of the toxicity and hazard of nonylphenols and nonylphenol ethoxylates to human health and the environment for the scientific justification of regulatory restrictions

Introduction. The identification of chemicals of concern is one of the main directions in the field of international chemical safety. These chemicals have negative impact on human health and the environment possessing carcinogenic, mutagenic, reprotoxic, endocrine disruptors effects as well as acute and chronic toxicity to aquatic biota. Therefore, they need to be regulated both at the national and international levels. The identification of these substances serves as the basis for subsequent regulatory changes, including development of hygienic and environmental standards, as well as prohibitive and restrictive measures.

Some international organizations refer nonylphenols and their ethoxylated derivatives to the chemicals of concern. As nonylphenols and nonylphenol ethoxylates are widely used in industry and household being the parts of detergents, paints and varnishes, polymer dispersions, pesticides, petrochemical and other products, they can affect a large number of people from different age groups. Therefore, they have come into focus of national scientific and regulatory organizations.

The purpose of this study is a comparative analysis of the toxicity and hazard of nonylphenols and nonylphenol ethoxylates for human health and the environment, as well as identification the priority areas for their further regulation.

Material and methods. The objects of the study were nonylphenols, including technical mixtures and individual linear and branched isomers (CAS 25154-52-3, 84852-15-3, 104-40-5), as well as ethoxylated derivatives with varying degrees of ethoxylation (CAS 9016-45-9, 37205-87-1, 7311-27-5, 68412-54-4), widely used as nonionic surfactants. Toxicity and hazard assessment was carried out based on the information from the official open national and international sources: ARIPS database “Hazardous Substances”, ECHA CHEM, PubChem, ECOTOX, documents of the US Environmental Protection Agency (US EPA), as well as publications indexed in the databases Scopus, Web of Science, PubMed, ResearchGate, eLIBRARY.RU and CyberLeninka. The physical and chemical properties of substances, environmental fate, (eco)toxicity, international and national regulation, and possible chemical alternatives are under discussion.

Results. The comparative analysis has shown that nonylphenols are more hazardous to human health and the environment than nonylphenol ethoxylates. Nonylphenols have negative impact on reproductive and endocrine systems. In addition, they possess pronounced corrosive properties and high toxicity to aquatic biota. In contrast, nonylphenol ethoxylates do not have reproductive and endocrine effects, but their environmental fate with the formation of nonylphenols and low ethoxylated derivatives as well as high aquatic toxicity make them hazardous. The national and international approaches to regulation were also discussed with the identification of some promising chemical alternatives that need to be evaluated.

Limitations. The study is limited to the analysis of open literature sources, including Scopus, Web of Science, PubMed, ResearchGate, Cyberleninka, RSCI, eLIBRARY.RU databases.

Conclusion. The results obtained can be used for the justification of national regulatory changes in relation to nonylphenols and nonylphenol ethoxylates, including the development and implementation of prohibitive and restrictive measures, as well as the gradual replacement of these compounds with safer alternatives.

Compliance with ethical standards. The study does not require a report from the Bioethics Commission.

Authors’ contribution:
Khamidulina Kh.Kh., Tarasova E.V. – concept and design of the study, editing, approval of the final version of the article, responsibility for the integrity of all parts of the article;
Kurpidinov K.S., Gonyukova E.S., Nazarenko A.K. – collecting and processing material, writing text, editing.

Conflict of interest. Khamidulina Kh.Kh., Tarasova E.V. are members of the editorial board of the journal “Toxicological Review”, but have nothing to do with the decision to publish this article. The article has passed the review procedure accepted in the journal. The authors declare no other conflicts of interest.

Funding. The study was carried out as part of the research project “Development and scientific substantiation of chemical alternatives to replace highly hazardous components in various types of products” in accordance with the set of process activities “Research and development work to ensure chemical and biological safety of the Russian Federation” of the state program of the Russian Federation “Scientific and technological development of the Russian Federation”.

Received: May 20, 2026 / Accepted: August 3, 2026 / Published: September 16, 2026

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