Toxicity assessment of plants raised in sludge amended soil.

Abstract

Background: Sludge is being used as a soil supplement. Its amendment in soil has shown improvement in soil fertility, hence supporting plant growth and productivity. Toxicity assessment of crops raised in sludge amended is required before recommending it as a soil supplement with great potential. Methods: Toxicity of plants raised in sludge amended soil was evaluated by in vitro and in vivo studies. In vivo studies involved feeding tests with different doses of plant extract while in vitro studies were conducted where cell lines were treated with different doses of plant extract. Results: Male albino rats fed with different doses (50, 100 and 500 mg kg-1 body wt.) of aqueous plant extract (14 days) did not showed any significant differences in urea, creatinine and enzymes such as serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), aspartate aminotransferase (AST), alanine amino transferase (ALT), alkaline phosphate (ALP) in comparison to control. Lipid peroxidation (LPO), antioxidants viz. catalase, peroxidase, glutathione S-transferase, glutathione measured for liver and kidney tissues showed no differences within the treatments. Cytotoxic effect of ethanolic plant extract was measured via MTT assay in HeLa cell lines. Results showed no significant growth inhibition in cells treated with plant extract. Studies suggested that extract of plants raised in sludge amended soil did not pose any toxicity to animals, provided sludge is not composed of toxicants.