title: Determination of ethylenethiourea in urine by liquid chromatography-atmospheric pressure chemical ionisation-mass spectrometry for monitoring background levels in the general population.
abstract: This study reports a sensitive analytical method suitable for the quantitative analysis of ethylenethiourea (ETU) in human urine and its application to samples from the general population. Sample preparation involved the use of diatomaceous earth extraction columns to remove matrix interferences. Quantification was achieved by liquid chromatography-mass spectrometry using positive ion atmospheric pressure chemical ionisation. Within-day and between-day variability of 14% (n=10) and 11% (n=6), respectively, were obtained at 98 nmol/l (10 μg l(-1)). The assay was linear over the investigated range 2.5-245 nmol/l, with a limit of detection of 2.5 nmol/l. The method was applied to monitoring background levels of ETU in urine samples from the general population in the UK. Results obtained from 361 spot samples contained ETU levels ranging from less than the detection limit (54% of samples) to a maximum of 15.8 μmol/mol creatinine (14.3 μg/g creatinine). The 95th percentile was 5.7 μmol/mol creatinine (5.2 μg/g creatinine).
authors.affiliation: Health and Safety Laboratory, Harpur Hill, Buxton, SK17 9JN, UK. kate.jones@hsl.gov.uk
authors.forename: Kate
authors.initials: K
authors.lastname: Jones
authors.forename: Katan
authors.initials: K
authors.lastname: Patel
authors.forename: John
authors.initials: J
authors.lastname: Cocker
authors.forename: Ruth
authors.initials: R
authors.lastname: Bevan
authors.forename: Len
authors.initials: L
authors.lastname: Levy
mesh_terms: D001274:Atmospheric Pressure; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005031:Ethylenethiourea / Q000032:analysis*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D015203:Reproducibility of Results
chemical_list: D005031:Ethylenethiourea