A comprehensive analytical method for nearly 1000 semi-volatile organic compounds (SVOC) in sediments has been developed using an automated identification and quantification system with a GC-MS database. The results of recovery tests using model compounds, which comprise of 119 non-polar to polar compounds, showed that the method can quantitatively analyze most SVOC, except for very polar substances. Analytical results of a standard reference material were close to certified concentrations. The detection limits of the method were 4 μg/kg when measuring by TIM and 0.4 μg/kg by SIM. The method was applied to actual sediments in rivers in Ho Chi Minh City, Vietnam. A large number of substances, including persistent organic pollutants, which seem to be discharged from domestic sources, were found at relatively high concentrations. From these results, it is confirmed that the developed method is a useful way to obtain a holistic picture of pollution by SVOC, and is a good tool for rapid screening of chemical pollution in sediments.

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The aim of this study is to develop the quick ultrasonication extraction procedure for determination of 16 typical polycyclic aromatic hydrocarbons (PAHs) in air particles. The  determination and quantification of PAHs in air particles samples were performed using gas chromatography coupled to mass spectrometry (GC-MS) with the aid of deuterated PAH internal standards. 1ug mixture of PAHs was spiked to a quarter of quartz fiber filter and extracted with four different solvents/solvent mixtures (methanol:dichloromethane, acetone:dichloromethane; acetone:hexane; dichloromethane). Ultrasonication extraction was carried out in dark at uncontrolled and controlled ultrasonication temperature (25-28oC). The unique extraction time (20 minutes) was applied for all experiments. The results showed that high recovery rate of PAHs (82-108%) were obtained with dichloromethane (as extraction solvent) in dark at ultrasonication temperature of 25 to 28oC, while generally low recovery rate of PAHs, especially naphthalene (57%) were obtained with methanol:dichloromethane (1:1). The ultrasonication extraction method with dichloromethane showed good reproductively and repeatability with relative standard deviation of 16 PAHs below 6,14%, confirming that samples analyses were precise.  Analytical results of PAHs in air particles collected in Hanoi using the developed ultrasonication extraction procedure showed that 15 out of 16 PAHs were detected, in which high molecular weight (MW) PAHs (>5 rings) were abundance compared to low molecular weight PAHs (< 3 rings). This developed ultrasonication extraction method is quick, easy and sufficient for determination of PAHs in air particle