Use of Morus alba-Bombyx mori as a useful template to assess Pb entrance in the food chain from wastewater

Abstract

This study focused on a 75-d microplot experiment to access lead (Pb) entrance into the terrestrial ecosystem using Morus alba (mulberry) and Bombyx mon (silkworm) as pollution indicator sources. The Pb (II) mobility in different systems was in the following order: synthetic effluents> soil> plant> larva> larvafecal. The Pb (II) mobility from an inorganic source to different life forms was found to be highly dependent on soil pH and the concentration of Pb in synthetic effluents. At lower concentrations, Pb was less lethal to B. mori larvae. Fifth instars of B. mori were found to be more tolerant to toxicity caused by Pb compared with lower instars. M. alba was not a hyperaccumulator plant because Pb (II) concentration was <1,000 mg/kg at all soil pHs and Pb (II) concentrations in effluents. The maximum amount of Pb(II) detected in soil, mulberry leaves, silkworm larvae, and silkworm feces was 326.5 ± 0.04,42.78 ± 0.02,61.24 ± 0.02, and 22.3 ± 0.02 mg/kg, respectively. © 2009 Entomological Society of America.