Assessment of heavy metal contaminations in vegetables consume in Johor Bahru

Abstract

Trace elements such as As, Pb, Hg, Cd, Fe, Ni, Cu, and Zn from organically and inorganically grown Brasssica (B.) were determined. In this study, X-ray fluorescence (XRF) technique was used for assessing concentration level of heavy metals (HMs) and its presence from all samples. All samples were obtained from 3 hypermarkets in Johor Bahru. These sampling techniques were known as “Market Basket Study”. Approximately, 1 kg of each vegetable was used and was analysed through standard laboratory procedures. The dried samples were grounded into powder form and by using test sieve mechanism, the size of the dried samples was found to be approximately 64 µm. The prepared samples in pellets form were analyzed using Wavelength Dispersive X-Ray Fluorescence (WDXRF) which compared to Standard Reference Material (SRM 1572) Citrus Leaves. The purpose is to detect the presence of trace elements such as As, Cd, Cu, Hg, Fe, Mn, Pb and Zn and their concentration level in vegetable samples. No significant different (p<0.05) of the HMs and mineral contents concentration between organic and inorganic Brassicas were observed except for Fe concentration from leaves. The concentration of HMs and trace elements in leaves is higher compare to stem, in the order of Fe > Zn > Mn > Cu > Pb > As > Hg > Cd. The HMs mean concentration of As, Hg, Pb and Cd in Brassicas samples were in the range of 1.94 – 2.55 ppm, 0.05 – 0.07 ppm, 8.33 – 10.91 ppm and 0.02 – 0.03 ppm, respectively. These values were exceeded the permissible level as stated in Food Act 1983 except for Cd, where As (1.00 ppm), Hg (0.05 ppm), Pb (2.00 ppm) and Cd (1.00 ppm).