Ecological risk assessment of chemical contaminants in stormwater sediments

Abstract

Contaminants bound to suspended solids transported by stormwater pose quantity and quality problems to the water ecosystem. Therefore, it is necessary to carry out an ecological risk assessment. Currently, Polish legal regulations do not require that stormwater sediments should be tested for hazardous substances prior to their removal. Ecological evaluation was performed for polycyclic aromatic hydrocarbons (PAHs) and heavy metals in the sediments from three selected stormwater sedimentation tanks located in urban catchment areas of Kielce city. The purpose this study was to analyze sediments for chemical contaminants and to demonstrate the relationship between contaminant levels and physical attributes of the catchment, including land use, drainage area, age of catchment and impervious surface in the watershed. Levels of PAHs and heavy metals (Cd, Cr, Ni, Pb and Zn) in stormwater sediments were then compared with Polish regulations and ecological screening values to determine their potential risk to environment were established. The results of the current study suggest that stormwater sediments are moderately contaminated with PAHs and heavy metals according to domestic regulations. They are, however, highly contaminated according to ecological benchmarks, which are exceeded several times.

Urban stormwater characterization, control, and treatment

“…Sediment in stormwater control and storage facilities also contains pollutants which can have ecotoxicological effects. When tested for PAHs, Cd, Cu, Cr, Ni, Pb, and Zn, the sediment in three stormwater tanks in Kielce City, Poland, had consistently high levels of Zn (Sałata, Bąk, & Górski, 2019). Several locations had Pb and Zn levels above the probable effect level (PEL), a threshold which aims to set a lower limit for when adverse biological effects may occur.…”

Urban stormwater sediment risk assessment from drainage structures in Bogotá, Colombia

“…7–9 Sediments act as indicators of environmental quality for stormwater because they can adsorb harmful pollutants such as nutrients, heavy metals, pesticides, and polycyclic aromatic hydrocarbons (PAHs) from the extensive and intensive impacts of anthropogenic activities. 10–14…”

“…[7][8][9] Sediments act as indicators of environmental quality for stormwater because they can adsorb harmful pollutants such as nutrients, heavy metals, pesticides, and polycyclic aromatic hydrocarbons (PAHs) from the extensive and intensive impacts of anthropogenic activities. [10][11][12][13][14] Most HMs become toxic at higher concentrations, while others are often neither toxic nor essential. [14][15][16] Trace metals and metalloids are enriched in urban environments, leading to their concentration values exceeding background values.…”