Abstract:Polycyclic aromatic hydrocarbons (PAHs), a group of persistent organic pollutants with high toxic properties, have been found in soil with high concentrations all over the world. However, the forms of PAHs in different particle-size fractions of soils have never been clarified heretofore. Here, the forms of pyrene as a representative PAH in different particle-size fractions of a yellow-brown soil were fractionated. Four soil fractions with different particle-size were obtained including fine sand (50~250 μm), silt (5~50 μm), coarse clay (1~5 μm), and fine clay (0.1~1 μm). Pyrene in each particle fraction was sequentially fractionated into three forms including desorbing fraction, non-desorbing fraction and bound residue. Pyrene was found to dominantly present as desorbing fraction and non-desorbing fraction in test soil. 6.00%, 4.66%, 34.68% and 40.88% of pyrene was found in fine sand, silt, coarse clay and fine clay, respectively. The concentrations of each form of pyrene in every particle-size fraction were in the order of non-desorbing fraction > desorbing fraction > bound residue. Non-desorbing and desorbing fraction were the dominant forms of pyrene in test particles, while bound residue contributed less than 1.18% to the total contents of pyrene in each particles with different particle-size. Clays (coarse and fine clays) were the dominant sink of pyrene in soil irrespective of soil desorbing fraction, non-desorbing fraction, bound residue and extractable fraction. Results of this work benefited the understanding of PAH sink in soil, and would be valuable for PAH risk assessment and pollution controls in the soil environment.
聂婧, 秦莉, 凌婉婷, 康福星, 高彦征. 芘在土壤不同粒径组分中的形态分布[J]. 中国环境科学, 2015, 35(9): 2721-2728.
NIE Jing, QIN Li, LING Wan-Ting, KANG Fu-Xing, GAO Yan-Zheng. The forms of pyrene in different particle-size fractions of soil. CHINA ENVIRONMENTAL SCIENCECE, 2015, 35(9): 2721-2728.