Accumulation of PAHs in plants from vertical flow-constructed wetland

Abstract

The aim of the investigation was to determine PAHs concentration in the biofilter and in parts of the plant taken from a wetland wastewater treatment plant vertical flow-constructed wetland in technical conditions. Determination of PAHs in parts of plants of Glyceria maxima: roots, stems, and leaves was carried out. The high pressure liquid chromatography with a diode array detector was used for qualification and quantification of PAHs. The extraction process for samples was carried out in an ultrasonic bath with dichloromethane as solvents. Then extracts were purified using SPE columns packed with silica gel in vacuum conditions. The 16 PAHs according to US EPA list were analyzed. The initial contents of total PAHs were 37 μg/kg dm on average. Concentration of these compounds in roots was twice as high (85 μg/kg dm). The highest concentration of analyzed hydrocarbons in leaves was noted (143 μg/kg dm). In extracts from the surface of leaves the total of PAHs concentration did not exceed 60 μg/kg dm. It demonstrates the ability of deposition of these compounds from the air. The content of PAHs in stems (92 μg/kg dm) was similar to the content of these compounds in roots (85 μg/kg dm).