Liquid chromatographic determination of N-methyl carbamate pesticide residues at low parts-per-billion levels in eggs.
A reversed-phase liquid chromatographic (LC) method is presented for the analysis of N-methyl carbamate pesticide residues and piperonyl butoxide in eggs at levels as low as 2 microg/kg (ppb). The study was undertaken to provide data for dietary exposure estimates used in risk analysis. The method uses an acetonitrile extraction followed by liquid-liquid partitioning and normal-phase aminopropyl solid-phase extraction column cleanup. Determination of residues is by reversed-phase LC with an inline postcolumn reaction followed by fluorescence detection. The average recoveries of 21 fortified (most at 2.0 and 20.0 ppb) N-methyl carbamate pesticide residues and the carbamate metabolite 1-naphthol from eggs ranged from 70 to 107%. Recoveries of the pesticide synergist piperonyl butoxide ranged from 63 to 106%. Single-comb White Leghorn hens were treated with the carbamate carbaryl, and the eggs subsequently produced were analyzed for carbaryl and 1-naphthol residues.
Schenck
Frank J
FJ
U.S. Food and Drug Administration, Southeastern Regional Laboratory, Atlanta, GA 30309, USA. fschenck@ora.fda.gov
Podhorniak
Lynda V
LV
Hobbs
James
J
Casanova
John
J
Donoghue
Dan
D
D000818:Animals; D002219:Carbamates / Q000032:analysis*; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002645:Chickens; D002853:Chromatography, Liquid / Q000379:methods*; D004531:Eggs / Q000032:analysis*; D005504:Food Analysis / Q000379:methods*; D005780:Gelatin / Q000737:chemistry; D009284:Naphthols / Q000032:analysis; D010573:Pesticide Residues / Q000378:metabolism*; D010575:Pesticides; D012306:Risk; D013997:Time Factors
D002219:Carbamates; D009284:Naphthols; D010573:Pesticide Residues; D010575:Pesticides; D005780:Gelatin; C036868:methyl carbamate