Effect of hydrolysis conditions on the determination of urinary 2,5-hexanedione in workers exposed or not exposed to n-hexane.

DOI Web Site Web Site PubMed 3 Citations
  • SAKAI Tadashi
    Center of Occupational Medicine, Tokyo Labor Accident Hospital
  • ARAKI Takaharu
    Center of Occupational Medicine, Tokyo Labor Accident Hospital
  • USHIO Koichi
    Center of Occupational Medicine, Tokyo Labor Accident Hospital
  • TAKEUCHI Yukiko
    Center of Occupational Medicine, Tokyo Labor Accident Hospital
  • IKEYA Yumiko
    Center of Occupational Medicine, Tokyo Labor Accident Hospital

Bibliographic Information

Other Title
  • 尿中２，５‐ヘキサンジオン（ＨＤ）のバックグランド値および作業者尿中ＨＤ濃度におよぼす加水分解条件の影響
  • ニョウチュウ 2 5 ヘキサンジオン HD ノ バックグランドチ オヨビ サギ

Search this article

Description

In order to determine the optimal conditions of acid hydrolysis for urinary 2, 5-hexanedione (HD) measurement, the effects of urine pH or volume of HCl added to urine and hydrolysis period were studied using gas chromatography-mass spectrometry (GC-MS). When 0.3 ml of concentrated HCl was added to 3 ml of urine, complete hydrolysis to liberate HD was attained 2 h after the start of heating at 100°C for urine from non-exposed subjects. On the contrary, in urine from exposed subjects most of HD was liberated in 30 min at 100°C, suggesting that the urinary substrates converted to HD by acid hydrolysis were different between exposed and non-exposed subjects. It was confirmed that hydrolysis for 2 h at 100°C with 0.3 ml of concentrated HCl added to 3 ml of urine gave the most reliable levels and the greatest amounts of HD in both urine from exposed and nonexposed subjects.<br>Reference values were determined by the hydrolysis conditions presented here. In 84 males, 52 females, and 136 with sexes conbined the urinary HD levels were 0.35, 0.49, and 0.39 mg/l (geometric mean), respectively. Urinary HD levels determined without hydrolysis (free HD) were less than 0.006 mg/l in 31 control subjects examined. In urine from exposed subjects the amount of free HD was about one-fifth of the total HD (free plus conjugated HD) as determined with acid hydrolysates, although the percentage of free to total HD varied from 0.4 to 28%.<br>In both urine from exposed and non-exposed subjects, total HD levels determined by GC-FID (flame ionization detector) were in good agreement with those by GC-MS (selected ion monitoring mode), indicating both can be useful for monitoring n-hexane exposure. Two normal urine metabolites, 2-acetylfuran and dimetylthiofene, were found close to HD peak in chromatograms, and were liable to interfere with the HD determination in GC-FID. To avoid the interference, use of non-polar long (50 m) capillary column is recommended for complete separation of HD from the interfering urinary constituents.

Journal

  • Sangyo Igaku

    Sangyo Igaku 34 (5), 440-447, 1992

    Japan Society for Occupational Health

Citations (3)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top