Altered Hematological and Biochemical Parameters in Schoolchildren Living in an Agricultural Community of Merida State, Venezuela

Abstract

Epidemiological studies have found that children living in a pesticide treated farmland have higher risk of developing cancer or other serious health problems. Their exposure to pesticides could be limited by periodic health assessments; however, there are few biomarkers for pesticide exposure. The aim of this work was to examine the effects of chronic exposure to pesticides on hematological and biochemical parameters in farm-resident children compared to urban-resident control children. A cross-sectional study was conducted in 72 farm schoolchildren and 41 controls; a follow-up study was done two years later on 20 participants. The children underwent a clinical examination, nutritional assessment, and blood sampling for complete hemogram and biochemical analysis of liver and renal functions, lipid and glucose metabolism, plasma cholinesterase, thyroid hormones and total antioxidant capacity. A prevalence of malnutrition and undernutrition were found in both exposed and control children. The most important hematological results were thrombocytosis in 48% of farm children, increased mean lymphocyte and monocyte counts, and decreased mean neutrophil counts compared to control. Butyrylcholinesterase activity was diminished in 35% of farm children. Alterations in biochemical parameters were observed between exposed and control groups, however, most of the results were within normal limits, except for the significant decrease in total antioxidant capacity. Follow-up study 2 years later showed normalized platelet and lymphocyte counts, however, decreased neutrophil counts was still observed. This study demonstrates that children living in an agricultural community are exposed to the health hazards of pesticides. Undernutrition and improper dental hygiene affect children’s overall health status and are likely to increase their vulnerability to toxic effects of pesticides.