ASSESSMENT OF BIOACCUMULATION OF LEAD AND CHROMIUM BY TOMATO AND SWEET PEPPERS

Abstract

Contamination of heavy metals represents one of the most pressing threats to soil and plants resources as well as human health. This study was designed to assess total contents of chromium and lead accumulated in plants of tomato and sweet peppers namely cherry, chili and red bell peppers planted on pots polluted with 10,20 and 30 mg/l Cr and 25,50 and 75 mg/l Pb separately in some pots and mixture of it in other pots. The concentration, transfer and accumulation of metals from soil to roots and shoots was evaluated in terms of Translocation (TF) and Bioaccumulation factors (BAF). The metal concentrations of Pb and Cr determined using Atomic Absorption Spectroscopy (AAS) showed that, the amount of Pb in tomato roots and shoots in dry weight varied between 1.80-106.24 mg/kg, Cr 2.40-230.97mg/kg. Cherry pepper Pb 9.9-563.30mg/kg,Cr 10.58-296.96. Chili pepper Pb 4.30-510mg/kg, Cr 0.025-320mg/kg. Red bell pepper Pb 2.05-24.42mg/kg Cr 53.19-176.23mg/kg. There were accumulation of Pb and Cr in fruits of red bell and cherry pepper, with little or no accumulation of Pb in fruit of tomatoes and chili peppers. Results of BAF and TF of Pb and Cr for most of the plants from the pots are less than one (TF < 1) meaning that they are not good accumulators of Pb and Cr. Also, the presence of Pb and Cr in pots affect the development and productivity of crops of chili, cherry and red bell peppers, but led to accumulation of the heavy metals in plants tomatoes without reducing the yield and quality of the production.