Nanoparticles “highly toxic” to the Arctic ecosystem
« on: 2011-04-07 18:25:02 »
Yet anther take on our impact on the global ecology.
Tiny industrial additives found in electronics kill microbes needed for plant life
Source: NUNATSIAQ NEWS
Silver nanoparticles are used to make fabric odor-resistant — but they have the potential to be "highly toxic" to Arctic ecosytem.
By looking at soil from the Arctic, researchers from Queen’s University have discovered that nanoparticles, tiny industrial additives put into everything from socks to salad dressing and suntan lotion, may cause “irreparably damaging effects” on soil systems and the environment.
“Millions of tonnes of nanoparticles are now manufactured every year, including silver nanoparticles which are popular as antibacterial agents,” said Virginia Walker, a professor in Queen’s biology department. “We started to wonder what the impact of all these nanoparticles might be on the environment, particularly on soil.”
Nanoparticles are part of many common household products, used in electronics, DVD players, cleaning products, textiles, fuel, paints, tires, ink cartridges.
To better understand the impact of nanoparticles, researchers acquired a sample of soil from the Arctic, because they felt this soil stood the greatest chance of being uncontaminated by any nanoparticles.
But they didn’t think the impact of adding nanoparticles to this soil would be as strong as it was.
“This is particularly concerning when you consider the vulnerability of the Arctic ecosystem,” Walker said.
The researchers first examined the uncontaminated Arctic soil samples before adding three different kinds of nanoparticles, including silver, to the soil.
Manufacturers often use silver nanoparticles because their antibacterial action slows the growth of odor-causing bacteria.
The researchers then let the soil samples sit for six months to see how the addition of the nanoparticles would affect tiny microbe communities already living in the soil.
What the researchers found was both “remarkable and concerning,” says an April 6 news release from Queen’s University, with results indicating that silver nanoparticles can be classified as “highly toxic.”
The original analysis of the uncontaminated soil from the Arctic had identified a beneficial microbe that helps fix nitrogen to plants — a process that’s essential for plant growth.
But the analysis of the Arctic soil sample six months after the addition of the silver nanoparticles showed little of this important nitrogen-fixing species remained.
Laboratory experiments, detailed in a paper in the April edition of the Journal of Hazardous Materials, showed that these microbes needed for plant growth were more than a million times susceptible to silver nanoparticles than other species.
The world has a history of welcoming innovations prior to reflecting on their impact on the environment, Walker said, such as the discovery of the insecticide DDT, the use of the drug thalidomide during pregnancy, and the widespread use of synthetic fertilizers.
Nanoparticles are known to enter the food chain as well, with previous studies finding traces of nanoparticles in wild mussels.
As for the health effects of nanoparticles, these need more study, according to a 2006 report from Quebec’s Robert Sauvé research institute.
“Although the various toxicological aspects and the diversity of the nanomaterials assessed are just beginning, many deleterious effects have been documented, particularly in animals… some of these nanoparticles have shown major toxic effects,” says the “Health effects of nanoparticles” report from the Institut de recherche Robert-Sauvé en santé et en sécurité du travail.