Determination of benzene, toluene, ethylbenzene and o-xylene in bottled waters by headspace solid-phase microextraction and gas chromatography/mass spectrometry

The amount of benzene, toluene, ethylbenzene, and o-xylene (BTEX) in 30 kinds of bottled waters purchased from market and 9 kinds of tap waters from home were determined using headspace solid phase microextraction (HS-SPME). The sample was stirred at 1200 RPM G for 4 min using a magnetic bar with 100 mu m PDMS as adsorbent for BTEX. Then it was desorbed from the fiber for 1 min at room temperature. Quantitation was achieved using standard calibration method. The limit of detection was determined as benzene 0.39 (+/- 0.04) ng/mL, toluene 0.08 (+/- 0.04) ng/mL, ethylbenzene 0.04 (+/- 0.01) ng/mL, and o-xylene 0.05 (+/- 0.02) ng/mL. Benzene and o-xylene were not detected in any samples, but toluene was detected in 11 samples, and ethylbenzene was detected just in 3 samples among 30 investigated bottled waters. The concentration range of investigated materials for toluene and o-xylene were 0.24 (+/- 0.09)-2.95 (+/- 0.08) ng/mL, 0.08 (+/- 0.06)-0.93 (+/- 0.10) ng/mL, respectively.