Selective, on-column extraction of organochlorine pesticide residues from milk.
A rapid procedure has been developed that allows a single-step, selective extraction of organochlorine pesticide (OCP) residues from milk on solid-matrix disposable columns by means of acetonitrile-saturated light petroleum. Recovery experiments were carried out on homogenized milk (3.6% fat content) spiked with an ethanolic solution of nine OCPs, viz., HCB, alpha-HCH, beta-HCH, gamma-HCH, heptachlor epoxide, dieldrin, endrin, p,p'-DDE and p,p'-DDT, at levels ranging from 0.002 mg/kg for alpha-HCH to 0.008 mg/kg for p,p'-DDT. Average recoveries of four replicates were 77% for HCB and almost quantitative (94-113%) for the other pesticides, with relative standard deviations from 2.9 to 7.3%. Coextracted fatty material amounted to about 5 mg/ml of milk before the clean-up. The described procedure also showed a satisfactory performance with milk powder. The extraction procedure requires about 60 min. The main advantages are that emulsions do not occur, several samples can be run in parallel by a single operator, reusable glassware is not needed and simple operations are required.
Di Muccio
A
A
Istituto Superiore di Sanità, Laboratorio Tossicologia Applicata, Rome, Italy.
Rizzica
M
M
Ausili
A
A
Camoni
I
I
Dommarco
R
R
Vergori
F
F
D000818:Animals; D002417:Cattle; D002849:Chromatography, Gas; D006843:Hydrocarbons, Chlorinated; D007306:Insecticides / Q000032:analysis*; D008892:Milk / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*
D006843:Hydrocarbons, Chlorinated; D007306:Insecticides; D010573:Pesticide Residues