[Show abstract][Hide abstract] ABSTRACT: Two freshwater sediments certified reference materials (CRMs) for 16 polycyclic aromatic hydrocarbons (PAHs) have been developed by the Institute for Environmental Reference Materials (IERM) of Ministry of Environmental Protection (MEP) in China. The methodology for preparing the CRMs of PAHs in sediments is described in this paper. The collected natural sediment samples were air-dried, ground, homogenised, packed, sterilised and tested on stability and homogeneity. Homogeneity results showed that the between-unit variation was confirmed to be below 4.5% for each compound. Stability was assessed after storage of samples for 16 months at temperature less than 30°C and in shade. The certification of the natural sediment matrix CRMs for PAHs was based on the agreement of results using different analytical techniques including gas chromatography/mass spectrometry (GC/MS) and reversed-phase liquid chromatography (LC) by no less than eight collaborating laboratories including IERM. Results of the homogeneity showed that the calculated ubb′ was 0.9–2.5% for environmental river standard-4 (ERS-4) and 9–2.3% for environmental lake standard-1 (ELS-1), whereas stability results of total 16 PAHs indicated that the calculated urel,lts was 4.2% for ERS-4 and 2.2% for ELS-1. Certified values of 16 PAHs in ERS-4 varied from 8.5 to 167 μg/kg and ranged from 0.036 to 2.8 mg/kg in ELS-1.The good comparability, together with the independent confirmation of the assigned mass fraction by using different methods, confirmed that the CRMs are suitable for the method validation and quality control in soil or sediments analysis.
No preview · Article · Aug 2015 · International Journal of Environmental Analytical Chemistry
[Show abstract][Hide abstract] ABSTRACT: A method was developed for the determination of organochlorine pesticide (OCP) residues in soil/sediment using high resolution gas chromatography coupled with low resolution mass spectrometry. The analytical procedures consisted of Soxhlet extraction, sulfur removal with copper powder, clean-up with gel permeation chromatography (GPC) and a florisil column of solid phase extraction (SPE). The analytes were separated on an HP-5MS capillary column, detected in selected ion monitoring ( SIM) mode and quantified using internal standard calibration curves of isotope dilution technique. The linear correlations of calibration standard solutions were good for all the OCPs. The recoveries and relative standard deviations of labeled compound solutions ranged from 60% to 110% and from 1.5% to 18%, respectively. The limits of detection ranged from 0.20 to 10.3 microg/kg were established for the 23 OCPs. The method showed satisfactory clean-up effect and precision quantification. It is suitable for the determination and confirmation of pesticides in complex matrices such as soil, sediment.
No preview · Article · May 2010 · Se pu = Chinese journal of chromatography / Zhongguo hua xue hui