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Tang J.,South China Agricultural University | Tang J.,Key Laboratory of Soil Environment and Waste Reuse in Agriculture of Guangdong Higher Education Institutes | Liu X.,South China Agricultural University | Liu X.,The Pearl River Water Environment Monitoring Center | And 9 more authors.
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae

The concentrations of organochlorine pesticides (OCPs) in water samples (n=18) collected from different sites of Liuxi River were determined using GC-MSD, and the Species Sensitivity Distributions (SSD) of different freshwater organisms exposed to OCPs was established. Based on OCP concentrations and SSD, the hazardous concentration for 5% the species (HC5) of OCPs to freshwater organisms were estimated, and the potential affected fractions (PAF) of various OCPs concentrations to freshwater organisms were also predicted. In addition, the ecological risk of OCPs in Liuxi River was assessed using quotient probability distribution. The results showed that the total concentrations of OCPs ranged from 216.41 to 389.70 ng·L-1 with a mean value of 293.02 ng·L-1. The HC5 value of α-Benzenehexachloride was very high (12.95 μg·L-1), while the HC5 values of Endosulfan sulfate and p, p'-DDD to freshwater organisms were below 0.10 μg·L-1, which might have large effects on ecological system. When the OCP concentration was 0.50 μg·L-1, the ecological risks of nine OCP compounds (except for α-BHC and Heptachlor) exceeded the 5% threshold. The quotient probability distribution showed that all the OCP compounds (expect for EndosulfanII) have potential ecological risks. Endosulfan sulfate posed the highest risk when 95% species were not affected at 95% confidential level. Source

Tan J.-H.,South China Agricultural University | Tan J.-H.,Guangzhou Quality Supervision and Testing Institute | Tang J.-J.,South China Agricultural University | Ouyang P.-Y.,South China Agricultural University | And 6 more authors.
Journal of Chinese Mass Spectrometry Society

A method of ultra-high performance liquid chromatography coupled with quadrupole time-of-flight high resolution mass spectrometry (UPLC-QTOF-MS) was developed for the determination of seven emerging pollutants in sediment, such as salicylic acid, naproxen, ibuprofen, ketoprofen, diclofenac, clofibric acid and triclosan. Sample was extracted with ultrasonic-assisted treatment using the mixture of formic acid-acetone (1:99, V/V) as extraction solvent, and then purified with solid-phase extraction using a mixed-mode anion exchange (MAX) cartridge, and finally detected by UPLC-QTOF-MS equipped with an electrospray ionization (ESI) source operated in negative mode. Qualitative screening was achieved according to the obtained experimental results with respect to mass accuracy, isotope distribution and relative abundance of the selected ions, i.e, a quasi-molecular ion and a fragment ion for each analyte, and retention time of the corresponding targeted compound. The positive samples, found to contain some/all of the targeted pollutants, were subject to MS/MS scan using the quasi-molecular ions of the analytes as precursor ions, thus generating fragmental ions for further confirmation. Quantification was performed with peak areas of extracted ions within a mass window of 0.05 Da. Satisfactory linearities (R2>0.99) are obtained for all analytes in the concentration range of 2-500 μg/L. Limits of detection (S/N=3) and limits of quantification (S/N=10) are in the range of 0.5-0.6 μg/kg and 1.5-2.0 μg/kg (dry weight (DW)), respectively. Recoveries are 87.8%-105.1% at three spiking levels with relative standard deviations (n=5) from 3.1% to 12.2%. The developed method was applied to the analysis of the investigated compounds in surface sediment samples collected from the Liuxi River in Guangzhou, and 4 pollutants are found with the highest concentration range of 6.51-12.26 μg/kg (DW). This method is efficient, accurate, and suitable for analysis of the seven investigated emerging pollutants in sediments. © 2016, Editorial Board of Journal of Chinese Mass Spectrometry Society. All right reserved. Source

Tao L.,CAS Guangzhou Institute of Geochemistry | Wu J.-P.,CAS Guangzhou Institute of Geochemistry | Zhi H.,Sun Yat Sen University | Zhang Y.,The Pearl River Water Environment Monitoring Center | And 3 more authors.
Environmental Science and Pollution Research

While the flame retardant chemical, tetrabromobisphenol-A (TBBP-A), has been frequently detected in the environment, knowledge regarding its species-specific bioaccumulation and trophic transfer is limited, especially in the highly contaminated sites. In this study, the components of an aquatic food web, including two invertebrates, two prey fish, and one predator fish, collected from a natural pond at an electronic waste (e-waste) recycling site in South China were analyzed for TBBP-A, using liquid chromatography-tandem mass spectrometry. The aquatic species had TBBP-A concentrations ranging from 350 to 1970 pg/g wet weight, with higher concentrations in the invertebrates relative to the fish species. Field-determined bioaccumulation factors of TBBP-A in the two aquatic invertebrates were nearly or greater than 5000, suggesting that TBBP-A is highly bioaccumulative in the two species. The lipid-normalized concentrations of TBBP-A in the aquatic species were negatively correlated with the trophic levels determined from stable nitrogen isotope (δ15N) (r = −0.82, p = 0.09), indicating that this compound experienced trophic dilution in the current food web. © 2016 Springer-Verlag Berlin Heidelberg Source

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