Aflatoxin exposure in breastfeeding children has yet to be extensively explored in the southeastern region of Kenya, which is prone to aflatoxin outbreaks, and the assessment of potential risks may be underestimated. We determined the aflatoxin exposure of children 0-6 months and the outcome of weight-for-age z-scores as part of a larger cross-sectional study involving 170 randomly selected mother-child dyads. A semi-structured questionnaire was used to collect information on breastfeeding practices. Children’s weights were also measured. Breast milk samples of 48 lactating mothers and their children's urine were collected from households whose food samples were collected for aflatoxin analysis. Aflatoxin levels were determined using enzyme-linked immunosorbent assays. The Statistical Package Software for Social Sciences (version 27) and Palisade's @Risk software were used for analysis. Exclusively breastfeeding children were 44.1% (75/170). The prevalence of aflatoxin M1 in breast milk was 77.1% (37/48) (concentration 35 ng/l; SD, 0.0), and the mean intake was 0.47 mg/kg b.w.t/day. All urine (100%) had aflatoxin M1 (mean 0.39 ng/ml (SD, 0.16). The exposure levels through breast milk were alarmingly high (margin of exposure < 10000) regardless of breastfeeding status, with complementary feeding potentially increasing the risks. Mothers' diets significantly contributed to aflatoxin M1 in breast milk and urine (p = 0.01). Socioeconomic status, household size, and age of lactating mothers were not significant predictors of aflatoxin M1 exposure (p > 0.05). Aflatoxin M1 exposure did not influence the weight-for-age z-scores (pall > 0.05). The results indicate high exposure levels among children 0-6 months, and breastfeeding practices could be one of the under-evaluated risk factors.

The authors have declared no competing interest.

This work was partially financed by the EU-funded Novel Staple Food-Based Strategies to Improve Micronutrient Status for better Health and Development in Sub-Saharan Africa (INSTAPA) Project under the Kenya Country Leadership of Dr. Alice Mboganie Mwangi.

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Ethical issues at all stages were considered in the study by obtaining ethical clearance (P454/08/2013) from Kenyatta National Hospital/the University of Nairobi-Ethical Review Committee (KNH/UoN-ERC).

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The data is available on figshare platform as a dataset (Aflatoxin in food, breast milk of lactating mothers, and urine of children below 6 months and associated data). DOI:10.6084/m9.figshare.28247918

https://doi.org/10.1111/mcn.13493