title: Risk assessment of thiacloprid and its chemical decontamination on eggplant, Solanum melongena L.
abstract: BACKGROUND
  Thiacloprid [(Z)-3-(6-chloro-3-pyridylmethyl)-1,3-thiazolidin-2-ylidenecyanamide; Calypso] is a systemic insecticide having persistence in the plant system. It was chosen for the management of the eggplant shoot and fruit borer, Leucinodes orbonalis Guen. Management of this insect pest is difficult because it harbours inside the shoot and fruit portions of eggplant. The persistence of thiacloprid on eggplant has not been studied in India. The Food and Agriculture Organisation (FAO) has proposed its maximum residue limit (MRL) on eggplant as 0.7 mg kg(-1), and there is a need to validate this value. Since residues were found to be above this level, five different decontamination agents were tested for the decontamination of thiacloprid from eggplant.
  
  
  RESULTS
  The half-life of thiacloprid was 11.1 and 11.6 days from trials in 2 years. Safety factors such as theoretical maximum daily intake (TMDI) and maximum permissible intake (MPI) were used to arrive at a risk assessment to human health from the analytical data obtained from the field trials. Thiacloprid at the doses tested (30 and 60 g AI ha(-1)) was not effective in managing eggplant fruit borer. A waiting period of 3 days before harvest of the fruits after insecticide application and a processing factor (PF) could not ensure a sufficient margin of safety (MOS). Subjecting the data to a processing factor of 60% could not bring the residues below the proposed MRL.
  
  
  CONCLUSIONS
  Thiacloprid is not found to be an appropriate and effective agent for application to eggplant. Either the proposed MRL needs to be revised or good agricultural practice involving thiacloprid for plant protection in eggplant cultivation is required.
authors.affiliation: Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi 110012, India. jksmenon@gmail.com
authors.forename: Jayakrishnan
authors.initials: J
authors.lastname: Saimandir
authors.forename: Madhuban
authors.initials: M
authors.lastname: Gopal
authors.forename: Suresh
authors.initials: S
authors.lastname: Walia
mesh_terms: D000818:Animals; D003666:Decontamination; D007313:Insecta / Q000187:drug effects; D007306:Insecticides / Q000494:pharmacology; D007700:Kinetics; D000073943:Neonicotinoids; D010573:Pesticide Residues / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry* / Q000494:pharmacology; D032323:Solanum melongena / Q000737:chemistry*; D013843:Thiazines / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D007306:Insecticides; D000073943:Neonicotinoids; D010573:Pesticide Residues; D011725:Pyridines; D013843:Thiazines; C417209:thiacloprid