title: Optimization and determination of polycyclic aromatic hydrocarbons in biochar-based fertilizers.
abstract: The agronomic benefit of biochar has attracted widespread attention to biochar-based fertilizers. However, the inevitable presence of polycyclic aromatic hydrocarbons in biochar is a matter of concern because of the health and ecological risks of these compounds. The strong adsorption of polycyclic aromatic hydrocarbons to biochar complicates their analysis and extraction from biochar-based fertilizers. In this study, we optimized and validated a method for determining the 16 priority polycyclic aromatic hydrocarbons in biochar-based fertilizers. Results showed that accelerated solvent extraction exhibited high extraction efficiency. Based on a Box-Behnken design with a triplicate central point, accelerated solvent extraction was used under the following optimal operational conditions: extraction temperature of 78°C, extraction time of 17 min, and two static cycles. The optimized method was validated by assessing the linearity of analysis, limit of detection, limit of quantification, recovery, and application to real samples. The results showed that the 16 polycyclic aromatic hydrocarbons exhibited good linearity, with a correlation coefficient of 0.996. The limits of detection varied between 0.001 (phenanthrene) and 0.021 mg/g (benzo[ghi]perylene), and the limits of quantification varied between 0.004 (phenanthrene) and 0.069 mg/g (benzo[ghi]perylene). The relative recoveries of the 16 polycyclic aromatic hydrocarbons were 70.26-102.99%.
authors.affiliation: Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, P. R. China.
authors.forename: Ping
authors.initials: P
authors.lastname: Chen
authors.forename: Hui
authors.initials: H
authors.lastname: Zhou
authors.forename: Jay
authors.initials: J
authors.lastname: Gan
authors.forename: Mingxing
authors.initials: M
authors.lastname: Sun
authors.forename: Guofeng
authors.initials: G
authors.lastname: Shang
authors.forename: Liang
authors.initials: L
authors.lastname: Liu
authors.forename: Guoqing
authors.initials: G
authors.lastname: Shen
mesh_terms: D002606:Charcoal / Q000032:analysis*; D005591:Chemical Fractionation / Q000379:methods*; D005308:Fertilizers / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*
chemical_list: D005308:Fertilizers; D011084:Polycyclic Aromatic Hydrocarbons; C540010:biochar; D002606:Charcoal
keywords: Accelerated solvent extraction; Biochar; Fertilizer; Polycyclic aromatic hydrocarbons; Response surface methodology