Assessment of Paediatric Health Risk Associated with Trace Metals and Polycyclic Aromatic Hydrocarbons (Pahs) Contamination in Cereal-Based Baby Foods from the Greater Accra Region

Abstract

Dietary intake is a major route of human exposure to contaminants. Cereal-based baby foods, which are often used to complement breastfeeding can be contaminated with toxic compounds. Consequently, the health of babies can be compromised upon exposure to such contaminants depending on the concentrations and/or as a result of contaminant bioaccumulation even at trace levels. It should be expected that cereal-based baby food must be manufactured using high-quality raw materials and the best processing technology. However, this is not often the case as contaminants such as polycyclic aromatic hydrocarbons (PAHs) and trace metals (eg. cadmium and lead among others) can be introduced into baby foods due to poor processing protocols. This work, therefore, sought to evaluate the presence of polycyclic aromatic hydrocarbons (PAHs) and trace metals in locally produced cereal-based baby foods and estimate their toxicological effect on babies. To achieve the objectives, 50 samples comprising of varying cereal compositions (maize, rice, millet, wheat) were sampled from sales outlets including major markets and hospitals in the Greater Accra region of Ghana. Samples were analyzed for metal content using atomic absorption spectrometry (AAS) following acid digestion (HNO3 - H2O2). PAHs were extracted following the QuEChERS method and analysed using Gas Chromatography-Mass spectrometry (GC/MS). The results showed contamination of both metals and PAHs in the samples. The concentrations of the metals across all the 50 samples were in a range: 0.87–34.74 mg/kg (Fe), <0.001–1.00 mg/kg (Zn), <0.003–0.92 mg/kg (Cu), <0.002–0.82 mg/kg (Cd), <0.001–0.26 mg/kg (Cr), <0.005–0.23 mg/kg (Co), <0.001–0.58 mg/kg (Pb), and <0.001– 0.20 mg/kg (Ni). The mean concentrations (mg/kg) of metals that were predominantly measured were: 8.60 (Fe), 0.06 (Pb), and 0.20 (Cd). The risk indices (HI) were in a range of 0.10–59.84, 0.13–84.53, and 0.20–123.69 for the ages 6–8 months, 9–11 months and 12–23 months respectively with cadmium as the main contributing factor to the risk index. This observation is indicative of potential child health risks. Mean concentrations of ΣPAHs (15 PAHs), ΣPAH4 [benzo(a)anthracene, chrysene, benzo(a)pyrene, and benzo(b)fluoranthene)], and benzo(a)pyrene [BaP] were 276.7 ± 256.2 μg/kg, 16.0 ± 32.2 μg/kg, and 5.0 ± 9.0 μg/kg respectively. Approximately 33.3 % of the samples analysed had concentrations of carcinogenic PAHs exceeding the FAO/WHO recommended limit of 1.0 μg/kg. The calculated carcinogenic risks (Rcar) for babies were in the ranges: 2.47 x 10 -6–1.40 x 10-5 (6–8 months) , 3.32 x 10-6–1.88 x 10-5 (9–11months), and 5.10 x 10-6 –2.88 x 10-5 (12–23 months) , while mutagenic risk (Rmut) were in the ranges: 2.47 x 10 -6–2.05 x 10-5, 3.32 x 10-6–2.75 x 10-5 and 5.10 x 10-6–4.23 x 10-5 for the ages 6–8 months, 9–11 months, and 12–23 months respectively. The health risk assessment showed that the presence of Pb, Cd, and BaP in the samples could potentially cause both carcinogenic and non-carcinogenic risks to babies in the Greater Accra region if they should be exposed via consumption of cereal-based baby foods. The outcome of such studies is necessary towards safeguarding public health, particularly babies.