Serum Levels of Circulating Immune Complexes and Nitric Oxide in Farmers Exposed to Pesticides in Southwestern Nigeria
DOI:
https://doi.org/10.51152/jbarbiomed.v11i1.256Keywords:
Pesticide exposure, Circulating immune complexes, Nitric oxide, Oxidative biomarkers, Immunotoxicity, Occupational exposureAbstract
The widespread use of pesticides in agriculture has raised significant concerns about their long-term health effects, particularly among chronically exposed farmworkers. This study investigated the serum levels of circulating immune complexes (CICs) and nitric oxide (NO) in pesticide-exposed farmers in Southwestern Nigeria, exploring their role as biomarkers of immune activation and oxidative stress. A case-control study design was employed involving 50 farmers with ≥10 years of pesticide exposure and 39 unexposed controls. CIC and NO levels were quantified using polyethylene glycol precipitation and Griess reagent assays, respectively. Data were analyzed using Mann-Whitney U and Kruskal-Wallis tests. Correlations were evaluated using Spearman’s rho. Farmworkers demonstrated significantly higher CIC levels (87.21 ± 60.34 Eq/ml) compared to controls (60.16 ± 40.74 Eq/ml; p < 0.05). NO levels were also markedly elevated in exposed farmers (88.74 ± 35.92 µM) relative to controls (53.41 ± 22.79 µM; p < 0.05). A significant positive correlation was found between NO levels and duration of pesticide exposure (r = 0.489, p < 0.001), while a negative correlation existed between CIC levels and exposure duration (r = –0.367, p < 0.05). Chronic pesticide exposure is associated with heightened immune complex accumulation and oxidative stress, predisposing farmworkers to immune dysregulation and potential long-term health risks. Regular biomonitoring using CIC and NO may offer early insight into pesticide-induced immunotoxicity.
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