Biomonitoring of Dietary Mycotoxin Exposure and Associated Impact on the Gut Microbiome in Nigerian Infants

Mycotoxins are toxic chemicals that adversely affect
human health.
Here, we assessed the influence of mycotoxin exposure on the longitudinal
development of early life intestinal microbiota of Nigerian neonates
and infants (NIs). Human biomonitoring assays based on liquid chromatography
tandem mass spectrometry were applied to quantify mycotoxins in breast
milk (n = 68) consumed by the NIs, their stool (n = 82), and urine samples (n = 15), which
were collected longitudinally from month 1–18 postdelivery.
Microbial community composition was characterized by 16S rRNA gene
amplicon sequencing of stool samples and was correlated to mycotoxin
exposure patterns. Fumonisin B1 (FB1), FB2, and alternariol monomethyl ether (AME) were frequently quantified
in stool samples between months 6 and 18. Aflatoxin M1 (AFM1), AME, and citrinin were quantified in breast milk samples
at low concentrations. AFM1, FB1, and ochratoxin
A were quantified in urine samples at relatively high concentrations. Klebsiella and Escherichia/Shigella were dominant in very early
life stool samples (month 1), whereas Bifidobacterium was dominant between months 3 and 6. The total mycotoxin levels
in stool were significantly associated with NIs’ gut microbiome
composition (PERMANOVA, p < 0.05). However, no
significant correlation was observed between specific microbiota and
the detection of certain mycotoxins. Albeit a small cohort, this study
demonstrates that mycotoxins may influence early life gut microbiome
composition.