SMELLY SOCKS

In 2012 scientists started a study of silver nanoparticles in the water at the federal Experimental Lakes Area of Ontario. In 2013 there was a delay as the existence of this facility was uncertain. However, with the decision to continue the ELA the study also continued.

Silver nanoparticles are used in some socks, athletic clothing and in industry. The clothing is treated with nanosilver for its antimicrobial properties to keep it from smelling. But when it is laundered, this study discovered that silver particles escape into the environment and are harmful to fish.

Yellow perch experienced reduced consumption and metabolism rates and their populations declined. The study will soon be published in the Archives of Environmental Contamination and Toxicology.

Chris Metcalfe, senior author of this study and Director of the Institute for Watershed Science at Trent University said the silver particles “got distributed around the lake and stayed quite a while…good for the experiment but not good for the fish.”

Canadian guidelines limit the amount of silver to a maximum of 0.25 parts per million for mining operations and Metcalfe thinks that could also apply to nanosilver. “I would counsel provincial and federal governments to start monitoring water downstream from wastewater treatment plants.”

The study found that half of the tiny particles remained suspended and half sank to the lake bottom. During the spring some bottom particles became resuspended. Nonosilver entered the fish almost immediately and accumulated rapidly leading to their decline.