Evaluation of Liver Biomarker Levels in Farmers Occupationally Exposed to Pesticides: A Cross-Sectional Study

Background/Objectives: Occupational pesticide exposure is a recognized hepatotoxic hazard; however, biomonitoring data characterizing liver function among Vietnamese agricultural workers remain scarce. This study compared serum hepatic biomarkers between pesticide-exposed fruit farmers (exposed group) and a non-exposed reference group (unexposed group) in a northern province in Vietnam, and evaluated whether biomarker alteration varied with cumulative exposure duration. Methods: A cross-sectional study using convenience sampling was conducted from April to October 2022 among 150 adults, comprising 100 fruit farmers with ≥1 year of direct occupational pesticide exposure and 50 unexposed controls. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total and indirect bilirubin, alpha-fetoprotein (AFP), and glucose were quantified using clinical laboratory assays. Multivariable linear regression models, adjusting for age, sex, and body mass index (BMI), were used to evaluate associations between pesticide exposure duration and biomarker levels. Results: Pesticide-exposed farmers had significantly higher mean concentrations of ALT (28.88 vs. 22.36 U/L, p = 0.002), AFP (3.06 vs. 1.16 ng/mL, p < 0.001), total bilirubin (9.93 vs. 7.74 μmol/L, p < 0.001), and indirect bilirubin (8.40 vs. 5.26 μmol/L, p < 0.001) than unexposed controls. While mean AST did not differ (p = 0.105), the proportion of abnormal AST cases was significantly higher among exposed individuals (23% vs. 8%, p = 0.043). After adjustment for age, sex, and BMI in multivariable linear regression models, prolonged exposure (>10 years) remained modestly associated with higher AFP and bilirubin levels (p < 0.05), while associations with ALT and AST were not statistically evident (p > 0.05). Conclusions: These findings suggest a possible association between occupational pesticide exposure and subclinical hepatic alterations, supporting calls for regular health surveillance and enhanced protective measures among fruit farmers.