Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Silver nanoparticles may adversely affect environment

28.02.2013
In experiments mimicking a natural environment, Duke University researchers have demonstrated that the silver nanoparticles used in many consumer products can have an adverse effect on plants and microorganisms.

Fifty days after scientists applied a single low dose of silver nanoparticles, the experimental environments produced about a third less biomass in some plants and microbes.

These preliminary findings are important, the researchers said, because little is known about the environmental effects of silver nanoparticles, which are found in textiles, clothing, children's toys and pacifiers, disinfectants and toothpaste.

"No one really knows what the effects of these particles are in the environment," said Benjamin Colman, a post-doctoral fellow in Duke's biology department and a member of the Center for the Environmental Implications of Nanotechnology (CEINT).

"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 exposures," Colman said. CEINT's research is funded by the National Science Foundation and the Environmental Protection Agency

Previous studies have involved high concentrations of the nanoparticles in a laboratory setting, which the researchers point out, doesn't represent "real-world" conditions.

"Results from laboratory studies are difficult to extrapolate to ecosystems, where exposures likely will be at low concentrations and there is a diversity of organisms," Colman said.

Silver nanoparticles are used in consumer products because they can kill bacteria, inhibiting unwanted odors. 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.

The main route by which these particles enter the environment is as a by-product of sewage treatment plants. The nanoparticles are too small to be filtered out, so they and other materials end up in the resulting wastewater treatment "sludge," which is then spread on the land surface as a fertilizer.

For their studies, the researchers created mesocosms, which are small, man-made structures containing different plants and microorganisms meant to represent the environment. They applied sludge with low doses of silver nanoparticles in some of the mesocosms, then compared plants and microorganisms from treated and untreated mesocosms after 50 days.

The study appeared online Feb. 27 in the journal PLOS One.

The researchers found that one of the plants studied, a common annual grass known as Microstegium vimeneum, had 32 percent less biomass in the mesocosms treated with the nanoparticles. Microbes were also affected by the nanoparticles, Colman said. One enzyme associated with helping 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. The overall biomass of the microbes was also 35 percent lower, he said.

"Our field studies show adverse responses of plants and microorganisms following a single low dose of silver nanoparticles applied by a sewage biosolid," Colman said. "An estimated 60 percent of the average 5.6 million tons of biosolids produced each year is applied to the land for various reasons, and this practice represents an important and understudied route of exposure of natural ecosystems to engineered nanoparticles."

"Our results show that silver nanoparticles in the biosolids, added at concentrations that would be expected, caused ecosystem-level impacts," Colman said. "Specifically, the nanoparticles led to an increase in nitrous oxide fluxes, changes in microbial community composition, biomass, and extracellular enzyme activity, as well as species-specific effects on the above-ground vegetation."

The researchers plan to continue to study longer-term effects of silver nanoparticles and to examine another ubiquitous nanoparticle – titanium dioxide.

The rest of the team were Duke's Christina Arnaout, Claudia Gunsch, Curtis Richardson, Emily Bernhardt, Bonnie McGill and Justin Wright; Sarah Anciaux of Coe College, Iowa; Michael Hochella and Bojeong Kim of Virginia Tech University; Gregory Lowry and Brian C. Reinsch of Carnegie Mellon University, Pittsburgh; Jason Unrine at the University of Kentucky; and Liyan Yin of Wuhan Botanical Garden, China.

Richard Merritt | EurekAlert!
Further information:
http://www.duke.edu

More articles from Ecology, The Environment and Conservation:

nachricht Protecting fisheries from evolutionary change
27.04.2016 | International Institute for Applied Systems Analysis (IIASA)

nachricht From waste to resource – how can we turn garbage into gold?
27.04.2016 | DLR Projektträger

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Erste Filmaufnahmen von Kernporen

Mithilfe eines extrem schnellen und präzisen Rasterkraftmikroskops haben Forscher der Universität Basel erstmals «lebendige» Kernporenkomplexe bei der Arbeit gefilmt. Kernporen sind molekulare Maschinen, die den Verkehr in und aus dem Zellkern kontrollieren. In ihrem kürzlich in «Nature Nanotechnology» publizierten Artikel erklären die Forscher, wie bewegliche «Tentakeln» in der Pore die Passage von unerwünschten Molekülen verhindern.

Das Rasterkraftmikroskop (AFM) ist kein Mikroskop zum Durchschauen. Es tastet wie ein Blinder mit seinen Fingern die Oberflächen mit einer extrem feinen Spitze...

Im Focus: Nuclear Pores Captured on Film

Using an ultra fast-scanning atomic force microscope, a team of researchers from the University of Basel has filmed “living” nuclear pore complexes at work for the first time. Nuclear pores are molecular machines that control the traffic entering or exiting the cell nucleus. In their article published in Nature Nanotechnology, the researchers explain how the passage of unwanted molecules is prevented by rapidly moving molecular “tentacles” inside the pore.

Using high-speed AFM, Roderick Lim, Argovia Professor at the Biozentrum and the Swiss Nanoscience Institute of the University of Basel, has not only directly...

Im Focus: 2+1 ist nicht immer 3 - In der Mikro-Welt macht Einigkeit nicht immer stark

Wenn jemand ein liegengebliebenes Auto alleine schiebt, gibt es einen bestimmten Effekt. Wenn eine zweite Person hilft, ist das Ergebnis die Summe der Kräfte der beiden. Wenn zwei kleine Teilchen allerdings ein weiteres kleines Teilchen anschieben, ist der daraus resultierende Effekt nicht notwendigerweise die Summe ihrer Kräfte. Eine kürzlich in Nature Communications veröffentlichte Studie hat diesen merkwürdigen Effekt beschrieben, den Wissenschaftler als „Vielteilchen-Effekt“ bezeichnen.

 

Im Focus: 2+1 is Not Always 3 - In the microworld unity is not always strength

If a person pushes a broken-down car alone, there is a certain effect. If another person helps, the result is the sum of their efforts. If two micro-particles are pushing another microparticle, however, the resulting effect may not necessarily be the sum their efforts. A recent study published in Nature Communications, measured this odd effect that scientists call “many body.”

In the microscopic world, where the modern miniaturized machines at the new frontiers of technology operate, as long as we are in the presence of two...

Im Focus: Winzige Mikroroboter, die Wasser reinigen können

Forscher des Max-Planck-Institutes Stuttgart haben winzige „Mikroroboter“ mit Eigenantrieb entwickelt, die Blei aus kontaminiertem Wasser entfernen oder organische Verschmutzungen abbauen können.

In Zusammenarbeit mit Kollegen in Barcelona und Singapur verwendete die Gruppe von Samuel Sánchez Graphenoxid zur Herstellung ihrer Motoren im Mikromaßstab. D

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

UFW-Fachtagung im Vorzeichen von Big Data und Industrie 4.0

03.05.2016 | Veranstaltungen

analytica conference 2016 in München - Foodomics, mehr als nur ein Modebegriff?

03.05.2016 | Veranstaltungen

Diabetes Kongress 2016: Diabetes schädigt das Herzkreislauf-System

02.05.2016 | Veranstaltungen

 
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Hepatitis C-Virus missbraucht den Fettstoffwechsel der Leber

03.05.2016 | Biowissenschaften Chemie

UFW-Fachtagung im Vorzeichen von Big Data und Industrie 4.0

03.05.2016 | Veranstaltungsnachrichten

Ein starkes Team: B2RUN und moove bringen Firmen in Bewegung

03.05.2016 | Unternehmensmeldung