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In this study, a new method for the determination of fipronil and its three metabolites in environmental water samples was developed based on meltblown nonwoven fabric solid‐phase extraction combined with gas chromatography‐electron capture detection. As the core material of medical masks, meltblown nonwoven fabric is made of polypropylene superfine fibers which are randomly distributed and bonded together with a relatively large specific surface area and good permeability. Polypropylene as a high molecular hydrocarbon‐based polymer has the characteristics of good hydrophobicity and lipophilicity, which can be applied for the separation and enrichment of hydrophobic substances in food, environment, and biological samples. The meltblown nonwoven fabric is soft and can fill the solid‐phase extraction cartridge tightly. This aspect also makes it suitable to be used as an ideal solid‐phase extraction sorbent. A series of parameters influencing the extraction efficiency were investigated, and under the optimized conditions, fipronil and its three metabolites had a good linear relationship in the range of 0.2–100 μg/L with a correlation coefficient R2 of more than 0.999. The recoveries at three spiked concentrations were in the range of 99.2–107.3% with the relative standard deviations less than 9.8% (intra‐day) and 8.1% (inter‐day). The limit of detection for the four target analytes was in the range of 0.02–0.06 μg/L. Finally, this method was successfully applied in the analysis of fipronil and its three metabolites in various types of environmental water samples.

In this work, a simple and miniaturized solid‐phase extraction device was constructed by connecting a commercial nylon needle filter to a syringe, which was applied for extracting 1‐hydroxypyrene from a urine sample via hydrophobic and hydrogen bond interactions. The nylon membrane in the needle filter acted as the solid‐phase extraction adsorbent, meanwhile, it filtered the particles in the urine sample. To obtain high extraction efficiency, key parameters influencing extraction recovery were investigated. The entire pretreatment process was accomplished within 5 min under the optimal conditions. By coupling high‐performance liquid chromatography–ultraviolet, a rapid, low‐cost, and convenient nylon needle filter‐based method was established for the analysis of 1‐hydroxypyrene in a complex urine matrix. Within the linearity range of 0.2–1000 μg/L, the method exhibited a satisfactory correlation coefficient (R = 0.9999). The limit of detection was 0.06 μg/L, and the recoveries from urine sample spiked with three concentrations (5, 20, and 100 μg/L) ranged from 105.8% to 113.1% with the relative standard deviations less than 6.7% (intra‐day, n = 6) and 8.9% (inter‐day, n = 4). Finally, the proposed method was successfully applied for detecting 1‐hydroxypyrene in urine samples from college students, smokers, gas station workers, and chip factory workers. The detected concentration in actual urine samples ranged from 0.46 to 5.26 μg/L. Taken together, this simple and cost‐effective nylon needle filter‐based solid‐phase extraction device showed an excellent application potential for pretreating hydrophobic analytes from aqueous samples.