Introduction. Poor regulation of active substances in disinfectants in Ukraine holds their legalization on the national market. Cluster approach in the hygienic regulation practice is one of the ways to address this issue. The aim of the study is to establish group-based hygiene regulations for the benzalkonium chloride (BC) cluster. Materials and methods of research. The subject of research is BC homologues. The research is based on the analysis of national and international scientific publications and legislative acts regarding BC toxic effects and hygienic regulations. Results. BC is a mixture of the benzalkonium chloride compounds homologues. The homologues ratio in a mixture plays a key role in assigning CAS numbers to BC. The average lethal doses with oral administration for all BC homologues are below 500 mg/kg. BC skin and oral absorption does not exceed 10 %. BC does not affect reproductive system and does not cause neonatal development abnormalities; it has no carcinogenic and mutagenic properties. Typical adverse effects of BC are related to compound irritant activity. Pursuant to EU regulation 1907/2006, substances with similar physicochemical, toxicological and ecotoxicological properties can be considered as a cluster. The data for reference substance of the cluster make it possible to predict the impact of other substances from this group on human health and environment. In case of BC, alkyl (C12–C16) dimethylbenzylammonium chloride was chosen as the reference substance. In Ukraine, the hygienic regulation sets 0.5 mg/m3 as occupational exposure limit for this substance. Following the clusters principle, it is advisable to introduce group hygiene regulations for all BC homologues based on alkyl (C12–C16) dimethylbenzylammonium chloride.
Conclusions. The implementation of cluster approach when developing exposure limits for chemical compounds in environmental medium makes it possible to introduce group hygienic regulations of 0.5 mg/m3 as occupational exposure limit for all BC homologues.
Key words: alkylbenzyldimethylammonium chloride, benzalkonium chloride, hygiene norm, cluster approach, group hygienic regulations

UDC 616-057:613.63/.65:547

Introduction. The situation of recent years during the SARS-CoV-2 pandemic has aggravated the problem of an insufficient number of approved hygienic standards of active substances included in disinfectants. This, in turn, has become a deterrent to the introduction of such agents into practice. For the proper organization of chemical safety of the workforce new methods of substantiating hygienic standards need to be developed. One of the ways to overcome the outlined higher problem, which will significantly speed up the resolution of the situation, is the introduction of read-across as an express method of substantiating the maximum permissible concentrations for a group (cluster) of compounds.

The purpose of the research is to substantiate the possibilities of developing group regulations for this cluster of compounds in the air of the working area based on data about the physicochemical and toxicological characteristics of dialkyldimethylammonium chloride С₈-С₁₀ homologues.

Results. Similar chemical structure of dialkyldimethylammonium chloride C₈-C₁₀ homologues determines their similarity in terms of physicochemical and toxicological properties. All substances are solids in their aggregate state, dissolve well in water, have the ability to penetrate biological membranes and disrupt their integrity. According to parameters of acute oral toxicity, dialkyldimethylammonium chloride C₈-C₁₀ homologues belong to moderately hazardous substances – hazard class 3, do not cause systemic toxicity; the main negative manifestation of their influence is an irritating effect which further provokes signs of general toxicity. The substances do not have carcinogenic, mutagenic effects, they do not affect reproductive function. The most studied representative of the cluster is didecyldimethylammonium chloride (DC₁₀DAC), which is accepted as a standard (analogue) for all dialkyldimethylammonium chloride C₈-C₁₀ homologues. In Ukraine a temporary hygienic standard for didecyldimethylammonium chloride in the air of the working area (approximately safe exposure level, ASEL) has been approved at the level of 0.2 mg/m³, where the limiting criteria for harmfulness are pronounced irritating effect on the skin and mucous membranes of the eyes and an acute inhalation effect. The calculation standard for quaternary ammonium compounds proposed by Dotson G.S. et al. is 0.1 mg/m³. Both standards belong to the II class of safety.

Conclusions. The read-across method allows for accepting didecyldimethylammonium chloride (DC₁₀DAC) as a standard (analogue) for all dialkyldimethylammonium chloride C₈-C₁₀ homologues. The hygienic regulation of the permissible content of didecyldimethylammonium chloride obtained on the basis of additional experimental studies as a result of the application of the cluster approach will be legitimate for dioctyldimethylammonium chloride (DC₈DAC); octyldecyldimethylammonium chloride (DC_8-10DAC), didecyldimethylammonium chloride (DC₁₀DAC) and their mixtures with different percentage ratios.

Keywords: dialkyldimethylammonium chloride C₈-C₁₀ homologues, dialkyl(C₈-C₁₀)dimethylammonium chloride, dioctyldimethylammonium chloride, didecyldimethylammonium chloride, read-across, hygienic standard, cluster approach, group hygienic regulation.