title: Pesticide residue levels in maize samples from markets in Lagos State, Nigeria.
abstract: BACKGROUND
  Pesticides are used widely in agriculture to control destructive pests and hence increase food supply. Their use inadvertently leads to residues in food crops and the environment. Pesticides, by nature are poisonous and exposure of humans to their residues may cause health hazards which include neurotoxicity and carcinogenicity among others. Evaluation of pesticide residues in food is therefore of public health importance and would help to ensure that levels are kept within safety limits.
  
  
  OBJECTIVE
  The aim of this study was to determine the incidence and quantity of organochlorine pesticide residues in maize samples collected from various markets in Lagos State and compare values obtained with established safety values in order to highlight possible health hazards.
  
  
  METHODS
  In this study, samples of white maize (Zea mays L.) purchased from different markets in Lagos State were analyzed for residues of organochlorine pesticides using gas chromatograph with mass spectrometric detector (GC-MS) after careful extraction and cleanup.
  
  
  RESULTS
  The results showed that 96% of the maize samples contained residues of one or more organochlorine pesticides. Mean concentrations ranged from 7.9-52.0 microg/kg and maximum residue limits (MRLs) of some pesticides were exceeded in up to 7% of samples. The estimated total diet intakes (ETDIs) for aldrin and dieldrin exceeded their maximum permissible intakes.
  
  
  CONCLUSIONS
  It is concluded that residues of organochlorine pesticides are present in maize in Lagos markets. Some exceed safety levels with possible adverse effects on human health. There is therefore a need for more stringent monitoring of the use of pesticides in agriculture and food storage in Nigeria.
authors.affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Lagos, Nigeria. onotsec@yahoo.com
authors.forename: C O
authors.initials: CO
authors.lastname: Ogah
authors.forename: H A B
authors.initials: HA
authors.lastname: Coker
authors.forename: A A
authors.initials: AA
authors.lastname: Adepoju-Bello
mesh_terms: D000383:Agriculture; D005506:Food Contamination / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D009549:Nigeria; D010573:Pesticide Residues / Q000009:adverse effects / Q000032:analysis*; D011634:Public Health; D003313:Zea mays
chemical_list: D006843:Hydrocarbons, Chlorinated; D010573:Pesticide Residues