Aflatoxin-lysine adducts in blood serum of the Malawian rural population and aflatoxin contamination in foods (groundnuts, maize) in the corresponding areas
Aflatoxin-lysine (AFB1-lys) adduct levels in blood samples collected from 230 individuals living in three districts of Malawi (Kasungu, Mchinji, and Nkhotakota) and aflatoxin B1 (AFB1) levels in groundnut and maize samples collected from their respective homesteads were determined using indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) methods. AFB1-lys adducts were detected in 67% of blood samples, with a mean concentration of 20.5 ± 23.4 pg/mg of albumin. AFB1 was detected in 91% of groundnut samples and in 70% of maize samples, with mean AFB1 levels of 52.4 and 16.3 μg/kg, respectively. All participants of this study reported consuming maize on a daily basis and consuming groundnuts regularly (mean consumption frequency per week: 3.2 ± 1.7). According to regression analysis, a frequency of groundnut consumption of more than four times per week, being female, and being a farmer were significant (p < 0.05) contributors to elevated AFB1-lys adduct levels in the blood. This is the first report on AFB1-lys adducts in blood samples of residents in Malawi. The results reinforce the urgent need for interventions, aiming at a reduction of aflatoxin exposure of the population.
KeywordsAFB1 contamination AFB1-lys adduct Exposure Women farmers Groundnuts Maize
The authors thank the National Health Science Research Committee (NHSRC), Malawi, for permitting the implementation of this study.
This study was financially supported by the McKnight Foundation (USA) and the CGIAR Research Program on Agriculture for Nutrition and Health (CRP A4NH).
Compliance with ethical standards
The study with human volunteers was approved by National Health Sciences Research Committee (NHSRC) of Malawi. All objectives of the study were clearly explained to the participants by medical professionals, and consent was obtained from each volunteer before collecting 10 ml of blood. In cases of minors, written consent was obtained from parents and guardians.
Conflict of interest
The authors declare that there is no conflict of interest.
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