Cross-sectional assessment of infants’ exposure to toxic metals through breast milk in a prospective cohort study of mining communities in Ghana

Abstract

BackgroundAlthough breastfeeding of infants is recommended globally, the fact that maternal toxic metal stores are mobilised into breast milk implies infants, whose mothers live and work in mining communities, are at risk of multiple exposure to mining related toxic metals, such as Lead (Pb), Mercury (Hg), Cadmium (Cd) and Arsenic (As), through breast milk intake, in addition to in utero exposure.MethodA total of 114 mother-baby pairs, recruited from two community hospitals servicing mining communities in two different regions in Ghana (57 each), were involved in this study. When the babies were 3 months old, the amount of breast milk intake, concentrations of selected toxic metals in the breast milk and therefore the amount of toxic metals exposure through breast milk were determined. The study also, determined the amount of these toxic metals in the hair and urine of each mother-baby pair at 3 months postpartum.ResultsBased on the amounts of milk intake and non-milk oral intakes (geometric mean of 0.701 (95% CL 0.59–0.81) Kg/day and median of 0.22 Kg/day respectively), 90% of the babies were determined to have been exclusively breastfed. The amounts of most of the toxic metals in breast milk were higher than the WHO set limits and for 46.4%, 33.3% and 4.4% of the babies, their intake of As, Hg and Pb respectively were above the WHO provisional tolerable daily intake (PTDI) values.ConclusionAn appreciable proportion of babies living within the communities served by the Mangoasi Community Hospital in the Obuasi Municipality of the Ashanti Region and the Dompime Health Centre in the Tarkwa Municipality of the Western Region were exposed to Hg, As and Pb through breast milk in excess of what they should and these may have health implication for the infants and therefore calls for interventions.

Essential and toxic elements in human milk concentrate with human milk lyophilizate: A preclinical study

“…Toxic organic substances, as well as toxic trace elements, which have been accumulate in the tissues of mothers can cross the mammary glands, exposing newborns to postnatal contamination through HM intake. Potential damage to neonatal growth and development caused by these toxic elements may be severe and permanent ( Bansa et al, 2017 ; Bassil et al, 2018 ; Bastos et al, 2018 ; Gil and Hernández (2015) ; Letinić et al, 2016 ; Rebelo and Caldas, 2016 ). Early exposure to excessive amounts of these potentially toxic elements can contribute to long-term adverse health effects, such as neurodevelopmental disorders and damage to immune and respiratory functions ( Cao et al, 2016 ; Heyer and Meredith (2017) ).…”

Double Burden of Malnutrition: Toxic Metals in Breast Milk May Limit the Amounts of Micronutrients Available to Infants through Breast Milk

“…Additionally, although the interaction of these elements (toxic and micronutrient) have been studied and reported for water, different body organs and body fluids, particularly blood, the interaction between these elements may defer depending on the body target, because different proteins, which are the carriers of these elements, are present in these different targets. This study wherefore, analyzed breast milk specimens collected from lactating mothers living and working in two mining areas in Ghana; these specimens have been previously shown to contain As, Hg, Pb at levels above the WHO provisional tolerable daily intake (PTDI) values, and Cd at levels below the PTDI [14]. In respect of the current micronutrient study, the amounts of Cu and Zn were used because these are thought to be biologically regulated [11], and also that their levels in breast milk may be affected by the presence of these toxic metals.…”

“…At enrolment, data on mother and infant demographic characteristics and locator information were collected with a structured questionnaire, by a one-on-one interview-based questionnaire administration (detail reported by Bansa et al, [14]). Participating mother-baby pairs were subsequently followed-up when the babies attained the ages of 3, 6, 9 and 12 months for specimen collection.…”

“…As depicted in Table 2 [14]), an infant's intake of each micronutrient was calculated relative to its body weight; the summary of these is reported as The amounts of these micronutrients excreted through urine by both the mothers and infants were very similar ( ranged between 0.01 and 0.1 mg/L of urine, the amounts of Se and Zn excreted ranged between, below detection limits (BDL) and 0.007, BDL and 0.008 mg/L of urine respectively. Table 4 presents the descriptive statistics of the amounts.…”

“…Therefore, following our earlier analysis of breast milk obtained from mothers living and working in mining communities in Ghana, for which As, Hg and Pb were above the WHO provisional tolerable daily intake (PTDI) values, for some of the breast milk samples [14], it was necessary for the further analysis of these breast milk samples to determine the amounts of micronutrients they contain.…”