Simple and automatic determination of aldehydes and acetone in water by headspace solid‐phase microextraction and gas chromatography‐mass spectrometry

Abstract

We describe a simple and automatic method to determine nine aldehydes and acetone simultaneously in water. This method is based on derivatization with 2,2,2‐trifluoroethylhydrazine (TFEH) and consecutive headspace‐solid‐phase microextraction and gas chromatography‐mass spectrometry. Acetone‐d₆ was used as the internal standard. Aldehydes and acetone in water reacted for 30 min at 40°C with TFEH in a headspace vial and the formed TFEH derivatives were simultaneously vaporized and adsorbed on polydimethylsiloxane‐divinylbenzene. Under the established condition, the method detection limit was 0.1–0.5 μg/L in 4 mL water and the relative standard deviation was less than 13% at concentrations of 0.25 and 0.05 mg/L. This method was applied to determine aldehydes and acetone in 5 mineral water and 114 surface water samples. All mineral water samples had detectable levels of methanal (24.0–61.8 μg/L), ethanal (57.7–110.9 μg/L), propanal (11.5–11.7 μg/L), butanal, pentanal (3.3–3.4 μg/L) and nonanal (0.3–0.4 μg/L). Methanal and ethanal were also detected in concentration range of 2.7–117.2 and 1.2–11.9 μg/L, respectively, in surface water of 114 monitoring sites in Korea.