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[Determination of formaldehyde in indoor air by gas chromatography].

Formaldehyde in indoor air was collected by water, derivatized with 2,4-dinitrophenylhydrazine and extracted by cyclohexane. The sample was separated on an OV-17 and QF-1 mixed chromatographic column and determined by electron capture detector. The detection limit was 0.02 mg/L (solution), the minimum detectable concentration was 0.01 mg/m3 while 10 L indoor air was collected. The results show that this is a rapid and sensitive method with less interferences and fairly good precision. The recoveries were 71.0%-90.4% and coefficients of variation were 4.1%-6.5%. The development of this method has made a reliable methodological foundation for the determination of formaldehyde in indoor air.