Silver nanoparticles have adverse ecological impact
Washington, Feb 28 : Researchers have demonstrated that the silver nanoparticles used in many consumer products can adversely effect plants and micro organisms.
"We're trying to come up with the data that can be used to help regulators determine the risks to the environment from silver nanoparticle exposure," Benjamin Colman, study co-author and post-doctoral fellow in Duke's biology department, was quoted as saying in the journal Public Library of Science One.
Silver nanoparticles are used in textiles, clothing, children's toys and pacifiers, disinfectants and toothpaste because they can kill bacteria, inhibiting unwanted odours, according to a Duke statement.
They work through a variety of mechanisms, including generating free radicals of oxygen which can cause DNA damage to microbial membranes without harming human cells.
These particles enter the environment as a by-product of sewage treatment plants. Too small to be filtered out, they end up in "sludge," which is then spread on the land surface as a fertilizer.
Silver nanoparticles also affected microbes, Colman said.
One enzyme that helped microbes deal with external stresses was 52 percent less active, while another enzyme that helps regulate processes within the cell was 27 percent less active.