Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCSB scientists examine effects of manufactured nanoparticles on soybean crops

21.08.2012
Sunscreens, lotions, and cosmetics contain tiny metal nanoparticles that wash down the drain at the end of the day, or are discharged after manufacturing.

Those nanoparticles eventually end up in agricultural soil, which is a cause for concern, according to a group of environmental scientists that recently carried out the first major study of soybeans grown in soil contaminated by two manufactured nanomaterials (MNMs).


Pictured are soybean stem, leaves, bean pods, and roots. The roots contain nodules where bacteria accumulate and convert atmospheric nitrogen into ammonium, which fertilizes the plant.

Credit: Patricia Holden

The team was led by scientists at UC Santa Barbara's Bren School of Environmental Science & Management. The team is also affiliated with the UC Center for Environmental Implications of Nanotechnology (CEIN), a $24 million collaboration based at UCLA, with researchers from UCSB, UC Davis, UC Riverside, University of Texas at El Paso, Columbia University, and other national and international partners. The results of the study are published this week in the Proceedings of the National Academy of Sciences.

"Our society has become more environmentally aware in the last few decades, and that results in our government and scientists asking questions about the safety of new types of chemical ingredients," said senior author Patricia Holden, a professor with the Bren School. "That's reflected by this type of research."

She explained that the research, which is funded by the National Science Foundation (NSF) and the U.S. Environmental Protection Agency (EPA), is helping to discover potential environmental implications of a new industry that includes nanomaterials. The ultimate goal is to help find more environmentally compatible substitutes, Holden said.

Soybean was chosen for the study due to its importance as a food crop –– it is the fifth largest crop in global agricultural production and second in the U.S. –– and because it is vulnerable to MNMs. The findings showed that crop yield and quality are affected by the addition of MNMs to the soil.

The scientists studied the effects of two common nanoparticles, zinc oxide and cerium oxide, on soybeans grown in soil in greenhouses. Zinc oxide is used in cosmetics, lotions, and sunscreens. Cerium oxide is used as an ingredient in catalytic converters to minimize carbon monoxide production, and in fuel to increase fuel combustion. Cerium can enter soil through the atmosphere when fuel additives are released with diesel fuel combustion.

The zinc oxide nanoparticles may dissolve, or they may remain as a particle, or re-form as a particle, as they are processed through wastewater treatment. At the final stage of wastewater treatment there is a solid material, called biosolids, which is applied to soils in many parts of the U.S. This solid material fertilizes the soil, returning nitrogen and phosphorus that are captured during wastewater treatment. This is also a point at which zinc oxide and cerium oxide can enter the soil.

The scientists noted that the EPA requires pretreatment programs to limit direct industrial metal discharge into publicly owned wastewater treatment plants. However, the research team conveyed that "MNMs –– while measurable in the wastewater treatment plant systems –– are neither monitored nor regulated, have a high affinity for activated sludge bacteria, and thus concentrate in biosolids."

The authors pointed out that soybean crops are farmed with equipment powered by fossil fuels, and thus MNMs can also be deposited into the soil through exhaust.

The study showed that soybean plants grown in soil that contained zinc oxide bioaccumulated zinc; they absorbed it into the stems, leaves, and beans. Food quality was affected, although it may not be harmful to humans to eat the soybeans if the zinc is in the form of ions or salts, in the plants, according to Holden.

In the case of cerium oxide, the nanoparticles did not bioaccumulate, but plant growth was stunted. Changes occurred in the root nodules, where symbiotic bacteria normally accumulate and convert atmospheric nitrogen into ammonium, which fertilizes the plant. The changes in the root nodules indicate that greater use of synthetic fertilizers might be necessary with the buildup of MNMs in the soil.

Holden commented on the likelihood of high concentrations of these nanoparticles in agriculture: "There could be hotspots, places where you have accumulation, including near manufacturing sites where the materials are being made, or if there are spills. We have very limited information about the quantity or state of these synthetic nanomaterials in the environment right now. We know they're being used in consumer goods, and we know they're going down the drain."

First author John H. Priester is a staff scientist in the Holden lab at UCSB. Other co-authors from UC CEIN are Yuan Ge, Randall E. Mielke, Allison M. Horst, Shelly Cole Moritz, Roger M. Nisbet, Joshua P. Schimel, Jose A. Hernandez-Viezcas, Lijuan Zhao, and Jorge L. Gardea-Torresdey. Co-authors Katherine Espinosa and Reid G. Palmer are affiliated with Iowa State University; Jeff Gelb is affiliated with Xradia Corporation; and Sharon L. Walker is with UC Riverside. NASA/JPL-Caltech, the USDA, and The University of Texas at El Paso were substantially involved in the research.

Gail Gallessich | EurekAlert!
Further information:
http://www.ucsb.edu

More articles from Agricultural and Forestry Science:

nachricht New insight into why Pierce's disease is so deadly to grapevines
11.06.2018 | University of California - Davis

nachricht Where are Europe’s last primary forests?
29.05.2018 | Humboldt-Universität zu Berlin

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

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

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>