title: Bioavailability and toxicity to rats of bound residues of 14C-pirimiphos-methyl in stored wheat.
abstract: Wheat grains were treated with 14C-pirimiphos-methyl to generate bound residues for testing their bioavailability to rats. Bound residues accounted for 25% of the applied dose (50 ppm) at the end of one year. When the grain bound residues were fed to rats for 48 hours the animals eliminated 30 and 40% of the administered dose in urine and feces respectively, after 5 days. Radioactivity in some selected organs and blood accounted for 37% of the administered dose after 2 days, which gradually declined to 1% after 5 days. These data indicate that wheat-bound pirimiphos-methyl residues are moderately bioavailable to rats. In a 90-day feeding study, inhibition of plasma cholinesterase and brain acetylcholinesterase strongly suggest that the bound residues possess a toxicological potential.
authors.affiliation: Biological Chemistry Division, Nuclear Institute for Agriculture and Biology, Faisalabad, Pakistan.
authors.forename: M J
authors.initials: MJ
authors.lastname: Qureshi
authors.forename: F F
authors.initials: FF
authors.lastname: Jamil
authors.forename: A
authors.initials: A
authors.lastname: Haq
authors.forename: S H
authors.initials: SH
authors.lastname: Naqvi
mesh_terms: D000818:Animals; D001682:Biological Availability; D002250:Carbon Radioisotopes; D002800:Cholinesterase Inhibitors / Q000633:toxicity; D005506:Food Contamination; D005511:Food Handling; D007306:Insecticides / Q000032:analysis / Q000493:pharmacokinetics* / Q000633:toxicity; D008297:Male; D009946:Organothiophosphorus Compounds / Q000032:analysis / Q000493:pharmacokinetics* / Q000633:toxicity; D010573:Pesticide Residues / Q000032:analysis / Q000493:pharmacokinetics* / Q000633:toxicity; D051381:Rats; D011919:Rats, Inbred Strains; D013154:Spleen / Q000187:drug effects; D014908:Triticum
chemical_list: D002250:Carbon Radioisotopes; D002800:Cholinesterase Inhibitors; D007306:Insecticides; D009946:Organothiophosphorus Compounds; D010573:Pesticide Residues; C014153:pirimiphos methyl