Aflatoxin exposure and cognitive performance in Mexican adolescents.

BACKGROUND

Aflatoxins are neurotoxic compounds that can cross the blood-brain barrier and have detrimental effects on developing brains. Human studies examining associations between aflatoxin exposure and cognitive outcomes, particularly during adolescence, remain limited.

OBJECTIVE

To examine the association between aflatoxin exposure and neurobehavioral and cognitive performance among Mexican adolescents.

METHODS

Participants included adolescents from the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) cohort. Aflatoxin-albumin adducts were measured in serum using the Enzyme-Linked Immunosorbent Assay (ELISA) method. Cross-sectional analyses examined associations between aflatoxin exposure and neurobehavioral performance measured using the Conners Continuous Performance Test, Third Edition (Conners CPT-3), at the early teen visit (N = 472). We also examined whether baseline aflatoxin exposure at the early teen visit was associated with cognitive performance at the late teen visit (N = 444) using three tests from the NIH Toolbox Cognition Battery (NIHTB-CB): Flanker, List Sorting, and Pattern Comparison. Multivariable linear regression models estimated associations between log-transformed aflatoxin-albumin adduct levels and cognitive outcomes. CPT-3 models were adjusted for school grade, body mass index (BMI), and socioeconomic status (SES), whereas NIHTB-CB models were adjusted for age, sex, school grade, BMI, and SES.

RESULTS

Mean (SD) age at the early- and late-teen visits was 14.3 (2.1) and 16.3 (2.1) years, respectively. Median serum aflatoxin-albumin adduct level was 126.5 ng/mL (IQR: 101-163). Higher baseline aflatoxin exposure was significantly associated with lower List Sorting scores (β = -2.84; 95% CI: -5.50, -0.16; P = 0.038). No significant associations were observed for other outcomes.

CONCLUSION

Higher aflatoxin exposure was prospectively associated with lower working memory performance among Mexican adolescents. These findings suggest a potential adverse association between aflatoxin exposure and cognitive function during adolescence that warrants further investigation in longitudinal studies.