RESUMEN
Abstract Benzo[a]pyrene (B[a]P) is a petroleum derivative capable of inducing cancer in human and animals. In this work, under laboratory conditions, we analyzed the responses of Colossoma macropomum to B[a]P acute exposure through intraperitoneal injection of four different B[a]P concentrations (4, 8, 16 and 32 μmol/kg) or corn oil (control group). We analyzed expression of the ras oncogene and the Hypoxia-inducible factor-1 alpha (hif-1α) gene using quantitative real-time PCR. Additionally, liver histopathological changes and genotoxic effects were evaluated through the comet assay. Ras oncogene was overexpressed in fish exposed to 4, 8 of 16 μmol/kg B[a]P, showing 4.96, 7.10 and 6.78-fold increases, respectively. Overexpression also occurred in hif-1α in fish injected with 4 and 8 μmol/kg B[a]P, showing 8.82 and 4.64-fold increases, respectively. Histopathological damage in fish liver was classified as irreparable in fish exposed to 8, 16 and 32 μmol/kg μM B[a]P. The genotoxic damage increased in fish injected with 8 and 16 μmol/kg in comparison with the control group. Acute exposure of B[a]P was capable to interrupt the expression of ras oncogene and hif-1α, and increase DNA breaks due to tissue damage.
RESUMEN
OBJETIVO: Evaluar si la exposición a plaguicidas y la desnutrición crónica son factores de riesgo para daño genotóxico en menores de tres años del municipio de Luribay del departamento de La Paz. Noviembre 2008. MATERIAL Y MÉTODOS: estudio de casos y controles. 155 niños y niñas menores de tres años estudiados, habitantes de ocho poblaciones de Luribay, La Paz - Bolivia de las 15 intervenidas por el Programa de Crecimiento Comunitario (Save the Children). Se aplicó a las madres una encuesta validada y adaptada al lugar para medir la exposición a plaguicidas y se realizó a los niños(as) la técnica de citoma bucal para determinación del daño genotóxico. RESULTADOS: un 61% de las madres se dedicaba a la agricultura, de ellas un 33% fumigó al menos una vez estando embarazada y 85% no utiliza equipo de protección completo. 83% de los niños presentan daño genotóxico, de ellos 84% se encuentran expuestos a plaguicidas. Los niños no desnutridos y expuestos a plaguicidas con daño genotóxico alcanzan un total de 35%. No se encontraron diferencias significativas entre los grupos de no desnutridos y expuestos a plaguicidas con Daño Genotóxico y los niños desnutridos crónicos y expuestos a plaguicidas también con Daño Genotóxico, (no desnutridos p=1,00) (desnutridos crónicos p=0,70). Los resultados en relación a la diferencia de edad en los pacientes con y sin daño genotóxico, son significativos (p=0.05).
OBJECTIVE: to assess whether exposure to pesticides and chronic malnutrition are risk factors for genotoxic damage in children under three years of age, of the municipality of Luribay, Department of La Paz. November -2008. METHODS: case study and control. 155 boys and girls were studied from eight Luribay towns, La Paz -Bolivia out of 15 involved by the Communitarian Development Program (Save the Children). A survey was applied, validated and adapted to the location in order to measure pesticide exposure, and the buccal cytome technique was applied on children for determining genotoxic damage. RESULTS: 61 percent of the mothers dedicated themselves to agriculture, out of them a 33 percent had fumigated at least once being pregnant, and 85 percent did not use appropriate protective gear. 83 percent of the children have genotoxic damage, out of them 84 percent are exposed to pesticides. Non-malnourished children and exposed to pesticides with genotoxic damage reach 35 percent. No meaningful differences were found between the group of Non-malnourished children and exposed to pesticides with genotoxic damage and the chronic malnourished children and exposed to pesticides with genotoxic damage, (Non-malnourished p=1,00) ( chronic malnourished p=0,70). Results concerning age difference in patients with and without genotoxic damage are meaningful (p=0.05).