Abstract
Formaldehyde and its metabolite, methanol, in the blood were determined by gas-liquid chromatography (GC) with a hydrogen flame ionization detector on 2.0 m glass column packed with 25% PEG 1000+2% KOH at 80°C. Formaldehyde and methanol in the blood sample were measured by head space gas method. n-Propanol as an internal standard was added to a vial containing the blood sample. The calibration curves of formaldehyde (0.2-1.2 mg/ml) and methanol (0.2-1.0 mg/ml) both showed a straight line. Recovery rates of formaldehyde added to the blood at various concentrations were 96.7±3.9% at 0.4 mg/ml, 97.7±2.7% at 0.8 mg/ml and 98.0±3.3% at 1.2 mg/ml. And recovery rates of methanol were 97.6±1.8% at 0.4 mg/ml, 97.6±0.7% at 0.6 mg/ml and 99.0±0.7% at 1.0 mg/ml. The contents of formaldehyde and methanol detected in the blood of the suicide were 0.773 mg/ml and 0.574 mg/ml respectively. Formaldehyde was identified as formaldehyde-2, 4-dinitrophenylhydrazone by GC-chemical-ionization mass spectrometry (CI-MS). Formic acid was determined by ion chromatography. The blood sample was diluted to 20 fold with water and the sample solution was injected into the chromatograph equipped with a SAX-251 column (250 mm) connected with a PAX-051 column (50 mm) as a pre column. Mobile phase was 10 mM Na2B4O7 solution. The content of formic acid detected in the blood of the suicide was 78μg/ml.
