Analytical methods for the determination of urinary 2,4-dichlorophenoxyacetic acid and 2-methyl-4-chlorophenoxyacetic acid in occupationally exposed subjects and in the general population.
Two methods for the quantitative analysis of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxyacetic acid (MCPA) in urine were compared.
The first was an high-performance liquid chromatography method using a C8 column with ion suppression and diode array detection.
The urine extracts were first purified by solid-phase extraction (SPE) on silica capillary columns.
The detection limit of the method was 15 mug/L for both compounds.
The percentage coefficient of variation of the whole analysis evaluated at a concentration of 125.0 mug/L was 6.2% for 2,4-D and 6.8% for MCPA.
The mean recovery of analysis was 81% for 2,4-D and 85% for MCPA.
The second was a gas chromatographic (GC) method in which the compounds were first derivatized with pentafluorobenzylbromide to pentafluorobenzyl esters, which were determined with a slightly polar capillary column and electron capture detection.
Before GC analysis, the urine extracts were purified by SPE on silica capillary columns.
This method had a detection limit of 1 mug/L for both compounds and a percentage coefficient of variation of the whole analysis, evaluated at a concentration of 30.0 mug/L, of 8% for 2,4-D, and of 5.5% for MCPA.
The mean recovery was 87% for 2,4-D and 94% for MCPA.
The low detection limit made the second method suitable for assaying the two herbicides in the general population. (...)
Mots-clés Pascal : Analyse chimique, Analyse quantitative, Pesticide, Herbicide, Polluant, 2,4-D, Liquide biologique, Urine, Homme, Chromatographie HPLC, Chromatographie phase inverse, Détecteur UV, Réseau diode, Extraction SPE, Etude comparative, Chromatographie phase gazeuse, Dérivatisation, Détecteur capture électron, Surveillance biologique, Exposition professionnelle, Médecine travail, Agriculteur, Acétique acide(aryloxy), MCPA, Toluène(alpha-bromo pentafluoro)
Mots-clés Pascal anglais : Chemical analysis, Quantitative analysis, Pesticides, Herbicide, Pollutant, 2,4-D, Biological fluid, Urine, Human, HPLC chromatography, Reversed phase chromatography, Ultraviolet detector, Diode array, Solid phase extraction, Comparative study, Gas chromatography, Derivatization, Electron capture detector, Biological monitoring, Occupational exposure, Occupational medicine, Farmer
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0400307
Code Inist : 002B03G. Création : 19/12/1997.