Comparison of heavy metal residue in selected processed canned tomato paste and bottled tomato sauce using atomic absorption spectrometry

Heavy metals are used to manufacture various types of packaging materials such as cans and glass bottle containers. Determination of heavy metal concentration presence in processed food products is crucial to identify specific possibly hazard metal contaminants and create public awareness upon consumption. A total of ten samples consisting of five different brands of canned tomato paste and bottled tomato sauce sold in Malaysia were analysed for the concentration of lead (Pb), cadmium (Cd), iron (Fe), zinc (Zn), chromium (Cr) and nickel (Ni) metals residues by Atomic Absorption Spectrometry (AAS). The average heavy metals concentration of all samples was arranged in increasing order, Cd > Ni > Cr > Pb > Zn > Fe. The highest level of metal was Fe (69.93 mg/kg) while the lowest was Cd (0.01 mg/kg). The concentration of Pb, Cr and Ni in all samples exceed the permissible limit set by the World Health Organisation 2011, the European Commission 2006 and the Malaysia Food Act and Regulation 1985 except Zn. There is a significant difference between heavy metal concentrations in canned tomato paste and bottled tomato sauce. Therefore, this study suggests efficient monitoring and inspection of both agricultural environment quality and industrial processing procedures.