title: Minor crops for export: a case study of boscalid, pyraclostrobin, lufenuron and lambda-cyhalothrin residue levels on green beans and spring onions in Egypt.
abstract: Dissipation rates of boscalid [2-chloro-N-(4' -chlorobiphenyl-2-yl)nicotinamide], pyraclostrobin [methyl 2-[1-(4-chlorophenyl) pyrazol-3-yloxymethyl]-N-methoxycarbanilate], lufenuron [(RS)-1-[2,5-dichloro-4-(1,1,2,3,3,3-hexafluoropropoxy)phenyl]-3-(2,6-difluorobenzoyl)urea] and lambda-cyhalothrin [(R)-cyano(3-phenoxyphenyl)methyl (1S,3S)-rel-3-[(1Z)-2-chloro-3,3,3-trifluoro-1-propenyl]-2,2-dimethylcyclopropanecarboxylate] in green beans and spring onions under Egyptian field conditions were studied. Field trials were carried out in 2008 in a Blue Nile farm, located at 70 kilometer (km) from Cairo (Egypt). The pesticides were sprayed at the recommended rate and samples were collected at pre-determined intervals. After treatment (T(0)) the pesticide residues in green beans were 7 times lower than in spring onions. This is due to a different structure of vegetable plant in the two crops. In spring onions, half-life (t(1/2)) of pyraclostrobin and lufenuron was 3.1 days and 9.8 days respectively. At day 14th (T(14)) after treatment boscalid residues were below the Maximum Residue Limit (MRL) (0.34 versus 0.5 mg/kg), pyraclostrobin and lambda -cyhalothrin residues were not detectable (ND), while lufenuron residues were above the MRL (0.06 versus 0.02 mg/kg). In green beans, at T(0), levels of boscalid, lufenuron and lambda -cyhalothrin were below the MRL (0.28 versus 2 mg/kg; ND versus 0.02 mg/kg; 0.06 versus 0.2 mg/kg, respectively) while, after 7 days treatment (T(7)) pyraclostrobin residues were above the MRL (0.03 versus 0.02 mg/kg). However, after 14 days the residue level could go below the MRL (0.02 mg/kg), as observed in spring onions.
authors.affiliation: Plant Protection Department, Ain Shams University, Cairo, Egypt.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Hanafi
authors.forename: Vincenzo L
authors.initials: VL
authors.lastname: Garau
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Caboni
authors.forename: Giorgia
authors.initials: G
authors.lastname: Sarais
authors.forename: Paolo
authors.initials: P
authors.lastname: Cabras
mesh_terms: D001549:Benzamides / Q000032:analysis*; D001713:Biphenyl Compounds / Q000032:analysis*; D002219:Carbamates; D007887:Fabaceae / Q000737:chemistry*; D005506:Food Contamination / Q000032:analysis; D006207:Half-Life; D009536:Niacinamide / Q000031:analogs & derivatives* / Q000032:analysis; D009570:Nitriles / Q000032:analysis*; D019697:Onions / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis*; D011720:Pyrazoles; D011722:Pyrethrins / Q000032:analysis*; D000073739:Strobilurins; D005466:Fluorocarbons
chemical_list: D001549:Benzamides; D001713:Biphenyl Compounds; D002219:Carbamates; D009536:Niacinamide; D009570:Nitriles; D010573:Pesticide Residues; D011720:Pyrazoles; D011722:Pyrethrins; D000073739:Strobilurins; C070364:fluphenacur; D005466:Fluorocarbons; C550088:2-chloro-N-(4-chlorobiphenyl-2-yl)nicotinamide; C513428:pyrachlostrobin; C037304:cyhalothrin