Aflatoxin exposure in adults in southern and eastern Mexico in 2018: A descriptive study

To estimate the frequency of detection and levels of aflatoxin B₁-lysine adduct (AFB₁-lys), an important hepatocellular carcinoma (HCC) risk factor, in eastern and southern Mexico.

We determined serum AFB₁-lys using mass spectrometry in a representative sample of 952 adults (weighted n = 7,493,354) from five states (Campeche, Chiapas, Tamaulipas, Veracruz and Yucatán) in 2018. We calculated overall and subgroup-specific frequency of detection and 95% confidence intervals (95%CI) and median AFB₁-lys levels and quartiles.

The overall frequency of detection of AFB₁-lys was 91.9% (95%CI 88.6, 94.3). The median AFB₁-lys level was 0.172 pg/μL (Q1-Q3, 0.060-0.582). Levels differed geographically (median pg/μL, 0.361 for Veracruz and 0.061 for Yucatan) and were higher among men and older individuals. Levels were almost three times higher in rural relative to urban areas (0.317 vs. 0.123 pg/μL). We observed higher AFB₁-lys exposure in lower socioeconomic status (SES) level populations.

AFB₁-lys frequency of detection was very high and exposure levels were highest in Veracruz, men, rural areas, and among persons of lower SES. Understanding modifiable HCC risk factors in populations with unique epidemiological patterns could inform preventative interventions.