Plasma Cholinesterase Levels and Health Symptoms in Peruvian Farm Workers Exposed to Organophosphate Pesticides

  • Hector C. Cataño
  • Elizabeth Carranza
  • Carlos Huamaní
  • Antonio F. Hernández


The purpose of this study was to examine plasma cholinesterase (PChE) changes and the adverse health effects associated with chronic low-dose exposure to organophosphates (OPs) in a Peruvian agricultural population. A cross-sectional study with a clinical interview and blood tests was performed among 213 farm workers from two subtropical valleys in Peru. The control group consisted of 78 nonexposed workers from the same areas. PChE levels from the two exposed subgroups (pesticide applicators and other agricultural jobs) were significantly lower than those of controls (1554 ± 315 U/l, 1532 ± 340 U/l, and 1787 ± 275 U/l, respectively). Fifteen percent of the exposed population reported a past poisoning by pesticides, all of them needing medical evaluation and treatment. They had significantly lower PChE levels as compared to those without this antecedent. Approximately 61% of the exposed workers reported pesticide-related symptoms, but no significant difference was found in their PChE as compared to workers without symptoms. On the other hand, the use of personal protective equipment (PPE) was significantly associated with higher PChE levels and with a lower risk of reporting pesticide-related symptoms, which supports the benefit from using appropriate protective measures. In conclusion, data indicate that farm workers exposed to OPs in developing countries need to be monitored by means of PChE and an examination of their clinical status, which would allow identification of farm workers most at risk from pesticide toxicity. The use of correct PPE is highly recommended.



We thank Percy Herrera and Carlos Cabrera for their technical help. This study was partially funded by Fundación Instituto Hipólito Unanue (Grant number 880/2004-CC-CD).


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Hector C. Cataño
    • 1
  • Elizabeth Carranza
    • 2
  • Carlos Huamaní
    • 3
  • Antonio F. Hernández
    • 4
  1. 1.Laboratorio de Biología Molecular, Instituto de Química Biológica, Microbiología y BiotecnologíaFacultad de Farmacia y Bioquímica, Universidad Nacional Mayor de San MarcosJardín BotánicoPerú
  2. 2.Laboratorio de Bioquímica. Instituto Nacional de Biología AndinaFacultad de Medicina, Universidad Nacional Mayor de San MarcosLimaPerú
  3. 3.Dirección Ejecutiva de Prevención y Control de Riesgos Ocupaciones y Ambientales, Centro Nacional de Salud Ocupacional y Protección del Ambiente para la Salud (CENSOPAS)Instituto Nacional de Salud (INS)LimaPeru
  4. 4.Department of Legal Medicine and ToxicologyUniversity of Granada Medical School18071-GranadaSpain

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