Environmentally Allowable Concentrations of Heavy Metals in the River Bolshaya Neva

Abstract

The purpose of the study is to substantiate the regional concentrations of heavy metals in the river Bolshaya Neva. To calculate the environmentally acceptable concentrations, primary data of hydrochemical monitoring for the period 2000–2011 were used, borrowed from the yearbooks of the St. Petersburg Center for Hydrometeorology and Environmental Monitoring with regional functions. The results of calculations of environmentally acceptable concentrations of five heavy metals (common iron, copper, lead, manganese, cadmium) in the river Bolshaya Neva are presented. Three different methods were used for calculations: the method of S.A. Patina, method D.G. Zamolodchikov and the method of E.V. Venitsianov and co-authors. For calculations by the method of S.A. Patina used two indicators – the average concentration of a chemical element for the period under review and the standard deviation. Calculations by the method of D.G. Zamolodchikov were based on the use of the upper and lower quartiles of the distribution. In calculations according to the method of E.V. Venitsianov and co-authors used three indicators – the sample size, the upper quartile of the distribution and the standard deviation for the quantile of about 0.75. Based on the principle of sanitary maximalism, the optimal method for calculating regional maximum permissible concentrations of heavy metals is substantiated – the method developed by E.V. Venitsianov and co-authors. A very high close relationship between the environmentally acceptable concentrations of heavy metals in the river Bolshaya Neva and their clarks in the earth's crust has been established. The results of predicting environmentally acceptable concentrations values for four metals (cobalt, nickel, zinc, aluminum) are presented.