Levels of aflatoxin M1 and selected heavy metals in the breast milk of lactating mothers in Owerri, Nigeria
Date
2020-02
Authors
Journal Title
Journal ISSN
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Publisher
Federal University of Technology, Owerri.
Abstract
Mother's breast milk which is the basic diet for infants is loaded with proteins, fats, carbohydrates and essential minerals which are necessary for proper nutrition of the infant. Regrettably, breast milk is also a likely source of aflatoxins and toxic metals which are unsafe for the breastfeeding child. In Nigeria, there is a paucity of information on aflatoxin and toxic heavy metals exposure, especially in the southeast region. In the present study, we assessed the level and frequency of breast milk AfM1 and some heavy metals as biomarkers of
maternal exposure. Breast milk samples were collected from a selected group of 40 lactating mothers of infants attending the Federal Medical Centre Owerri, Imo State, between June and August 2019. Some heavy metals (Pb, Cd, Cr, Cu, Zn, Fe, As, and Hg) were analyzed using Atomic Absorption Spectrophotometry while AfM1 levels were assessed by HPLC with
fluorescence detection after aflatoxin extraction. The mean (±standard deviation) concentration of AfM1 in the breast milk samples was 4.02±1.12 ng/L and 100% of all the samples contained AfM1 at 2.33 – 7.08 ng/L. AfM1 concentration was positively and significantly (p<0.01) associated with the daily consumption of cassava-based foods, groundnut oil, maize, tomatoes and dry fruit (p<0.05). No significant association (p>0.05) was observed between AfM1 concentration in breast milk with employment status and educational level in nursing mothers. The mean (±standard deviation) values of these heavy metals were Cd: 0.029±0.013 mg/L, Cr: 0.019±0.011 mg/L, Cu: 0.035±0.013 mg/L, Fe: 0.049±0.039 mg/L, Pb: 0.038±0.013 mg/L and Zn: 0.009±0.008 mg/L. The result of the estimated daily intake of breast milk by the breastfed infants shows that heavy metals such as Pb, Fe, and Cd are ingested more daily than other metals analyzed. There was a weak positive but non-significant correlation between heavy metal content and daily intake of maternal diet except for beans where a significant correlation (p<0.01) was found with Cr, Cu and Zn. A weak positive but non-significant correlation was also observed between exposure to heavy metals such as Cu, Fe and Pb and maternal diets. None of the samples exceeded the national and international legal regulatory limit for AfM1 and the selected heavy metals in breast milk except for chromium. Generally, their presence still poses a health risk.
Description
The master's thesis contains tables and figures
Keywords
Aflatoxin M1, heavy metals, breast milk, infants, Department of Biochemistry, exposure, Nigeria
Citation
Ekeanyanwu, C. L. (2020). Levels of aflatoxin M1 and selected heavy metals in the breast milk of lactating mothers in Owerri, Nigeria (Unpublished Master's Thesis). Federal University of Technology, Owerri, Nigeria