Development of an in-line system for the analysis of 4,4'-DDT in water.
An in-line system for trace persistent organic pollutants (POPs) in water was developed by using a laboratory-made hollow fiber membrane (HFM) unit connected with a high-resolution gas chromatograph-mass spectrometer (HRGC-MS). The semivolatile organic compound, 4,4'-Dichlorodiphenyl trichloroethane (4,4'-DDT), was chosen as a representative of a persistent organic compound. The synthetic water contaminated with 4,4'-DDT was passed through the HFM unit, the extraction occurred by the analyte pervaporated and permeated, then stripped into HRGC-MS. Several factors were investigated for the high extraction efficiency. The best performance was obtained at sample and stripping gas flow rates of 6 and 9 mLmin-1, respectively, and desorption temperature of 60 degrees C. At this temperature, the diffusion rate was enhanced by 15 times over 25 degrees C. A wide linear dynamic range was obtained, i.e., 0.10-1.0 mgL-1, with a limit of detection (LOD) of 90 microgL-1. The extraction efficiency of 4,4'-DDT in real water samples was in the range of 83-94%. Real water samples were analyzed and 0.6 microgL-1 of 4,4'-DDT was found in unregistered bottled water and 7.0 microgL-1 in tap water.
Peeraprasompong
Pensiri
P
Analytical and Environmental Chemistry/Trace Analysis Research Unit, Department of Chemistry, Prince of Songkla University, Songkhla, Thailand.
Thavarungkul
Panote
P
Kanatharana
Proespichaya
P
D000327:Adsorption; D003634:DDT / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods* / Q000592:standards; D008567:Membranes, Artificial; D010575:Pesticides / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013696:Temperature; D014835:Volatilization; D014874:Water Pollutants, Chemical / Q000032:analysis*
D008567:Membranes, Artificial; D010575:Pesticides; D014874:Water Pollutants, Chemical; D003634:DDT