title: Paraoxonase 1 and its relationship with pesticide biomarkers in indigenous Mexican farmworkers.
abstract: OBJECTIVE
  Biomarkers of pesticide toxicity and paraoxonase 1 (PON1) phenotype and genotypes were evaluated in indigenous Mexican farmworkers exposed mainly to organophosphate (OP) pesticides.
  
  
  METHODS
  Acetylcholinesterase, butyrylcholinesterase, and PON1 activities--arylesterase and CMPAase activities--were evaluated spectrophotometrically. PON1 55 and 192 polymorphisms were determined by real-time polymerase chain reaction. Hematological parameters were evaluated using a cytometer.
  
  
  RESULTS
  Butyrylcholinesterase and arylesterase activities were lower in farmworkers, who also showed lower levels of leukocytes but higher percentages of lymphocytes when compared with the nonexposed group. Our results showed a high frequency of OP, high hydrolysis-related PON1 alleles (LL/QR and LL/RR) in the study population. An association was observed between CMPAase activity and PON1Q192R polymorphism.
  
  
  CONCLUSIONS
  Our results suggest that pesticide exposure modifies biochemical and hematological biomarkers in the study population, and that the phenotype of PON1 (CMPAase) is a sensible susceptibility biomarker of OP pesticide toxicity.
authors.affiliation: From the Laboratorio de Contaminación y Toxicología Ambiental (Drs Bernal-Hernández, Medina-Díaz, Barrón-Vivanco, Robledo-Marenco, Girón-Pérez, and Rojas-García), Secretaría de Investigación y Posgrado, Universidad Autónoma de Nayarit, Tepic, Nayarit, Mexico; Posgrado en Ciencias Biológico Agropecuarias (Dr Bernal-Hernández), Unidad Académica de Agricultura, Universidad Autónoma de Nayarit, Xalisco, Nayarit, Mexico; Laboratorio de Enfermedades Crónicas y Degenerativas (Dr Pérez-Herrera), Unidad Interinstitucional de Investigación Clínica y Epidemiológica, Facultad de Medicina, Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico; Departamento de Toxicología (Dr Quintanilla-Vega), Centro de Investigación y de Estudios Avanzados del IPN, Mexico; and Facultad de Enfermería (Dr Cerda-Flores), Universidad Autónoma de Nuevo León, Monterrey, Mexico.
authors.forename: Yael Yvette
authors.initials: YY
authors.lastname: Bernal-Hernández
authors.forename: Irma Martha
authors.initials: IM
authors.lastname: Medina-Díaz
authors.forename: Briscia Socorro
authors.initials: BS
authors.lastname: Barrón-Vivanco
authors.forename: María de Lourdes
authors.initials: Mde L
authors.lastname: Robledo-Marenco
authors.forename: Manuel Iván
authors.initials: MI
authors.lastname: Girón-Pérez
authors.forename: Norma Elena
authors.initials: NE
authors.lastname: Pérez-Herrera
authors.forename: Betzabet
authors.initials: B
authors.lastname: Quintanilla-Vega
authors.forename: Ricardo
authors.initials: R
authors.lastname: Cerda-Flores
authors.forename: Aurora Elizabeth
authors.initials: AE
authors.lastname: Rojas-García
mesh_terms: D000110:Acetylcholinesterase / Q000097:blood; D000293:Adolescent; D000328:Adult; D000383:Agriculture; D043303:Aryldialkylphosphatase / Q000097:blood* / Q000235:genetics*; D015415:Biomarkers / Q000097:blood; D001772:Blood Cell Count; D002091:Butyrylcholinesterase / Q000097:blood; D002265:Carboxylic Ester Hydrolases / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D005838:Genotype; D006400:Hematocrit; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007306:Insecticides / Q000633:toxicity*; D008297:Male; D008800:Mexico; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D010755:Organophosphates / Q000633:toxicity*; D010573:Pesticide Residues / Q000633:toxicity; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D055815:Young Adult
chemical_list: D015415:Biomarkers; D006454:Hemoglobins; D007306:Insecticides; D010755:Organophosphates; D010573:Pesticide Residues; D002265:Carboxylic Ester Hydrolases; C019734:arylesterase; D000110:Acetylcholinesterase; D002091:Butyrylcholinesterase; D043303:Aryldialkylphosphatase