Assessment of carcinogenic risk caused by elevated 3,4-benz(a)pyrene concentration in soils in an industrial city

Apparent destructive changes in soils typically occur in residential areas within urbanized ecological systems formed in large industrial cities. Elevated concentrations of super-toxicants and xenobiotics in soils, polycyclic aromatic hydrocarbons included, create high potential health risks for city population. Our research goal was to assess the carcinogenic risk caused by elevated 3,4-benz(a)pyrene concentrations in soils in Taganrog, an industrial city with its population being about 250 thousand people located in Rostov region. The assessment included individual and population risks. There are two basic reasons which make the research vital. First of all, 3,4-benz(a)pyrene contents in soils in residential areas exceed hygienic standards. Secondly, the incidence of malignant neoplasms has been stably high in the city. We analyzed the results of determining 3,4-benz(a)pyrene concentrations in 384 soil samples taken in 2013-2020 at 19 monitoring posts (located within residential areas close to crossroads with intense traffic, recreational zones, and areas around pre-school children facilities). 3,4-benz(a)pyrene was established to be the priority pollutant in soils in the city with its share contribution to the complex pollution index (Csoil) being 55.25 %. 3,4-benz(a)pyrene concentrations were higher than maximum permissible ones in 65.63 % of all the examined soil samples; its average and maximum concentrations were equal to 2.298 and 45.525 MPC accordingly. We assessed the individual multi-route carcinogenic risk (CR) caused by elevated 3,4-benz(a)pyrene concentrations in soils. The risk turned out to be high (2.4606·10-3) and inhalation introduction was established as the priority one (94.84 %).