RESUMEN
Determination of Residues of Malathion [M] and its metabolic fractions Malaoxon [MO], 0, O-dimethyl-phosphoro dithionate [DPDT], Malathion mono acid [MCA], Dicarboxylic acid [DCA] and desmethylmalathion [DMM], in serum, urine and tissues of lactating goats received a daily dose [10mg-1 kg] body weight of [M] for 5 successive days was investigated. Daily samples of blood and urine were collected during the period of administration as well as 7 and 14 days after withholding of [M]. Tissue samples were taken from slaughtered goats at 7 and 14 days after cessation of the insecticide. Gas chromatographic technique [GC] was adopted for determination of [M] and its metabolites. [M] was not detected in any serum samples collected during administration and/or after cessation of insecticide, while it was excreted unchanged in urine and milk till one week after cessation of treatment with neurotoxic concentration over 20 ng/ml. The active metabolites [MO] and [DPDT] were not detected in any milk samples collected during application or after stoppage of [M] administration, while both metabolites were detected in serum and urine with neurotoxic concentrations during period of administration and still detected in serum for 7 days [400 ng/ml] and DPDT for 14 days [241 ng/ml] after stopping of [M] administration. The major excretory detoxified metabolites was found in milk on the days 7 and 14 after cessation of Malathion. Tissue residue-analysis