Studies Of Essential And Non-Essential Elements In Cereal-Based Weaning Foods For Infants Commercially Available On The Ghanaian Market
Date
2013-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Ghana
Abstract
Cereal-based weaning foods, which abound on the Ghanaian market, are nutritionally vital in the growth and development of infants. Recent reports in scientific literature however indicate that rice and other cereals used in the manufacture of the weaning foods contribute significantly to the intake of arsenic (As), cadmium (Cd) and lead (Pb) by infants. In view of this, frequent monitoring of the cereal-based weaning foods has become imperative. The study assessed the beneficial health effects and risks posed by the consumption of cereal-based weaning foods commercially available on the Ghanaian market with respect to the essential elements (Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Se, V and Zn) and, non-essential, potentially toxic elements (As, Br, Hg, Pb and Sn). Twenty (20) different brands of weaning foods were purchased from various retail outlets in Accra and used for the study. Instrumental neutron activation analysis (INAA) and atomic absorption spectrometry [with flame atomisation (FAAS) and hydride generation (HGAAS)] were used in analysing the samples. Determination of Pb using FAAS was done following its extraction with dithizone. The analytical methods were validated using certified reference materials NIST 1568a (Rice flour) and NIST 1547 (Peach leaves). The levels (μg/g, in ranges) obtained for the elements were: As (< 0.025), Br (<0.17-402), Ca (405-2002), Cl (158-5521) and Cr (<0.03-1.23). Others are: Cu (0.83-55.80), Fe (1.07-11.78), Hg (< 0.025), K (49-3845) Mg (20-280) and Mn (0.84-38.94). The rest include: Na (13-1588), Pb (0.025-0.093), Se (0.145-0.317), Sn (35.8-91.8), V (<0.01-0.990) and Zn (0.50-7.17). The daily intakes of the essential elements were also estimated, and generally found to be lower than recommended values set either by the FAO/WHO, the European Food Safety Authority (EFSA), the US Food and Nutrition Board, or the Joint Societies for Nutrition of Germany, Austria and Switzerland. The estimated
intake levels of the non-essential, potentially toxic elements As, Hg, Sn and Pb were all lower than their respective provisional tolerable weekly intake (PTWI) values established by the Joint FAO/WHO Expert Committee on Contaminants and Food Additives (JECFA). The results indicated that the analysed food samples were generally safe for consumption with respect to their content of the non-essential elements analysed. However, the contributions of the food samples to the daily essential element needs of the infant were mostly woefully inadequate, and this may not augur well for the proper growth and development of infants that consume them.
Description
Thesis (MPhil)
Keywords
Cereal-Based Weaning Foods, Infants, Commercial, Ghanaian Market