Assessment of aflatoxin M₁ exposure and associated determinants in children from Lahore, Pakistan

Aflatoxins are potent carcinogenic and immunomodulatory mycotoxins, and exposure may lead to deleterious effects on human health. This study aimed to detect aflatoxin M-1 (AFM(1)) as biomarker of exposure and determine associated risk factors in children attending a specialized-childcare hospital in Lahore. Urine samples collected from 238 children (1-11 years) during winter (January-mid-March 2020) and hot-humid summer (August-September 2020) were tested for AFM(1) presence using ELISA. Data on potential risk factors were also collected. Of 238 samples, 156 (65.5%) were positive for urinary AFM(1). Season was significantly associated (OR = 2.64; 95% CI = 1.49-4.79; p = 0.001) with AFM(1) positivity; prevalence was higher in hot-humid months (74.6%) than winter (57.3%). The place of living was also significantly associated (OR = 2.21; 95% CI = 1.25-3.97; p = 0.007), and urinary AFM(1) positivity was higher in urban children (71.1%) compared to rural (58.3%). Median value for creatinine-adjusted AFM(1) was 1.9 ng/mg creatinine (Q1-Q3 = 0.82-6.0 ng/mg creatinine), while non-creatinine-adjusted AFM(1) was 0.57 ng/mL (Q1-Q3 = 0.23-1.4 ng/mL). Significantly higher urinary AFM(1) levels were detected in children; age <= 2 years (p = 0.037), who consumed more milk (p = 0.048), and who presented to the nutrition clinic (p = 0.003). These findings highlight the need for an effective control program to reduce the AFM(1) burden in children.