Levels of toxic and trace metals in the breast milk of lactating mothers in Abeokuta, Ogun State, Nigeria

Background and objectives: Breast milk is an essential source of nutrients and energy for infants. The study analyzed for the levels of essential, toxic and rare earth elements in the breast milk of lactating mothers within Abeokuta metropolis. Materials and methods: Thirty-seven (37) breast milk samples were collected with consents of lactating mothers at Ogun State General Hospital in Abeokuta. The samples were digested using standard method and analyzed for essential, toxic and rare earth elements using Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The data were subjected to descriptive analysis. Results: The results showed higher concentrations of toxic elements than essential elements in the breast milk of lactating mothers, where five toxic metals: Ag, Ti, V, Pb and Ba were observed to be present in 11, 14, 15, 17 and 23 breast milk samples respectively. Two essential (P and S) and two toxic (Cd and Hg (except sample 19)) elements were observed to be present in all the breast milk samples. Rare Earth Elements (except Sr, U and Rb) were below the detection limit of the instrument. Though three breast milk samples (12, 14 and 17) were observed safe, they contained two toxic (Cd and Hg) and a rare earth trace (Rb) element. Conclusion: It could be concluded that despite the inherent benefits of human breast milk with essential elements to the infants, it can still be a source of toxic and trace earth metals contamination.