Toxic metals such as Cd, Cr, Pb and Hg, in trace amounts, enter the
   human body through food products. One of the main sources is the
   corrosion of the metal made apparatus, which are used in the process of
   food production. Tomato paste with an average pH value of 4.6 capable of
   containing such elements.

          The effect of metallic apparatus on the concentration of toxic metals in 
   tomato paste was evaluated. For this purpose 50 samples of tomato, 25
   samples of tomato juices and 61 samples of tomato pastes were collected ,
   and digested with nitric acid. Cadmium and chromium were determined,
   using atomic absorbtion (AA), lead (Pb) were determined using
   diphenylcarbazid and spectrophotometer. Mercury (Hg) was determined
   using cold vapor AA. Statistical method , ANOVA and Dunken tests  were
   used for data analysis. The percent of recovery of the methods were also
   determined.

         The results of the study indicated that the recovery of the methods were
   over than 93 percent, using the spiked samples of 1 and 5 PPM of the
   metals. The results of the study also showed that the concentration of the
   Cd, Cr, and Pb were below the standard level in home made tomato paste 
   samples.  The concentration of  Hg in all samples were below the standard
   level and the detection limit of the instrument used. The study also revealed
   that absence of Hg in all samples could be because of the lack of this
   element in the percent impurity of the apparatus used .

          Statistical analysis showed the significant differences between the
   methods of preparation of  tomato paste which confirm the role of non-
   standard apparatus in increasing the concentration of toxic elements in
   tomato paste.