Accumulation and Translocation of Chromium (Cr) and Lead (Pb) in Chilli Plants (Capsicum annuum L.) Grown on Artificially Contaminated Soil

Abstract

The current study is an endeavour to measure the bioaccumulation potentials of heavy metals in different parts of chilli plants (Capsicum annuum L.) grown in artificially contaminated soil with various concentrations of Cr and Pb. The concentrations of heavy metals were estimated by Atomic Absorption Spectroscopy (AAS) technique. The mean concentration of Cr and Pb accumulated in different parts of plants in high, medium, and low levels of contamination was in the following order: roots > leaves > shoots > fruits. Cr concentration in fruits was lower than that of the WHO standard. However, fruits grown on medium contaminated soil contained 0.695 mg/kg Cr which did not follow the safe guideline by SEPA. A significant amount of Pb was traced in fruits grown in highly contaminated soil that exceeded the standard limit set by FAO/WHO. Accumulation of Pb was higher than Cr at different levels of contamination in every part of the chilli plants. The transfer factor for Cr and Pd was found in the following order, leaves > shoots > fruits> roots and leaves > shoots > roots > fruits, correspondingly at every level of contamination. The bioconcentration factors were higher in Pb than Cr. The daily intake of metals in combination with health and carcinogenic risk indexes indicated that the edible parts of chilli plants are safe to consume as recommended by SEPA/WHO/FAO. The present study can be considered a reference for assessment and monitoring of heavy metals associated with human health risks in chilli plants at different industrially contaminated sites.