Effect of Heavy Metals on Bacterial Attachment in Soils

AbstractThe presence of both heavy metals and bacteria is frequently reported in urban storm water runoff. Adsorption and complexation of metals onto bacteria and soil takes place as storm water runoff infiltrates into the subsurface, potentially changing both bacterial and mineral surfaces, and altering the attachment of bacteria onto soil surfaces. Scanning electron microscopy and energy dispersive X-ray spectroscopy analyses were performed on soil samples equilibrated with synthetic storm water amended with copper, lead, and zinc to determine changes in the elemental content of soil. Sets of batch sorption experiments of Escherichia coli onto soil were conducted under different conditions by varying solution composition and soil exposure history. E. coli attachment increases in synthetic storm water with elevated heavy metals concentrations (Kd=0.0229  mL/mg) as opposed to nutrient buffer (Kd=0.0100  mL/mg) for the same untreated soil. For E. coli both suspended in nutrient buffer, Kd is higher when eq...