Application of gas chromatography-mass spectrometry for the determination of urinary ethylenethiourea in humans.
Ethylenethiourea (ETU) is a major metabolite of ethylenebisdithiocarbamate pesticides: a sensitive and specific assay for its determination in human urine is proposed below. ETU is extracted on a diatomaceous earth column using dichloromethane and derivatized with the mixture of N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide and tert-butyldimethyilsilyl chloride. The derivative is analyzed using GC/MS in the EI/SIM mode. The whole procedure is carried out in the presence of ethylenethiourea-d(4) as internal standard. The analytical features of the method are: high specificity, >90% recovery, range of linearity 0-200 microg/L, within- and between-run precision as coefficient of variation, <17 and <20%, respectively, limit of quantification 2 microg/L. In specimens stored in the dark at -20 degrees C ETU is stable for at least 6 months. The procedure was successfully applied to the biological monitoring of vineyard workers exposed to EBDTC and of a matched group of subjects from the general population.
Fustinoni
Silvia
S
Department of Occupational and Environmental Health, University of Milano and Istituti Clinici di Perfezionamento, Via S. Barnaba, 8-20122 Milano, Italy. silvia.fustinoni@unimi.it
Campo
Laura
L
Colosio
Claudio
C
Birindelli
Sarah
S
Foà
Vito
V
D005031:Ethylenethiourea / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016482:Urinalysis
D005031:Ethylenethiourea