Aiming to create more sustainable cities it is necessary to understand and manage different ecological factors which influence human health. One of such factors is black carbon (BC) in atmosphere, which currently is not commonly monitored by environmental monitoring systems. The aim of this research was to estimate by indirect approach the relation between eBC (equivalent of black carbon) concentration and other air pollutants in order to define approximate level of eBC in more efficient approach. The study was conducted in Wrocław (Poland) in October 2021, and combined data on eBC concentration (measured by microaethalometer), air quality (from national environmental monitoring system) and traffic (from municipal traffic management system). Quantile regression was used to assess the relationship between the concentrations of pollutants. The obtained results show that for rise 1 mg∙m^–3 of carbon monoxide, eBC concentration rise between 4.2 and 8.0 μg∙m^–3, depending on the period of a day. Precision of eBC concentration evaluation is influenced by sun light which results in higher precision of defining a scaling factor for night hours. Outcomes of this study constitute an added value to understanding of interconnections between different factors describing environmental conditions in cities and might be helpful for more effective environmental assessment of human habitats.