关键词: 多环芳烃类化合物, 1-硝基芘, 富集, 迁移, 土壤

Abstract: 【Objective】To elucidate the translocation and accumulation law of 1-nitropyrene from soil to plant, and thus to provide scientific data to support the research on dietary exposure risk to carcinogenic nitrated polycyclic aromatic hydrocarbons. 【Method】In this study, a soil-plant model was established through pot experiment, and blank, low-dose, high-dose polluted soils were used to plant scallion. Soil and plant (root and stem, leaf) samples were harvested after different growth period for analyzing 1-nitropyene levels, and the corresponding bio-concentration factors of each part were calculated by the bioaccumulation equation. 1-Nitropyrene levels and bioconcentration factors were compared with those of parent pyrene. The concentrations of 1-nitropyrene in plant and soil were determined by a modified QuEChERS method reported previously. After extraction and purification, a Fe/H⁺ derivatization process was followed up to convert the 1-nitropyrene to 1-aminopyrene to be quantitated by liquid chromatography coupled with fluorescence detection. The analytical method was validated using different part of scallion as matrix.【Result】The results showed that the analytical method demonstrated satisfied validation parameters, with the recovery ranged from 82.9% to 108.4% and RSDs no more than 13.2%. Concentration levels of 1-nitropyrene and pyrene in plant increased and then declined as time went by. Root and stem were the major part to uptake the 1-nitropyrene and pyrene via passive diffusion, while leaf only contributed 0.5-19.8% to the total uptake concentration of plant. Except for accumulating the pollutants from root via transpiration, the soil-air-leaf pathway contributed as well. The uptake and bioaccumulation behavior of pyrene was similar to that of 1-nitropyrene. 【Conclusion】1-Nitropyrene in soil could be translocated and accumulated to the edible part of plant, and stem is the major part to absorb 1-nitropyrene. Though the accumulation factors were similar, the toxicity of 1-nitropyrene was 10⁴ more toxic than parent pyrene, the corresponding dietary exposure risk has been increased. Thus, more attentions are needed to pay to nitro-PAHs.

Key words: polycyclic aromatic hydrocarbons, 1-nitropyrene, accumulation, translocation, soil