For four days in June, Viney Aneja discussed animal feces and agricultural by-products with 350 scientists from around the world in order to begin a dialogue that will affect everyone in America.
Aneja, a professor of marine and atmospheric sciences, is working beside Dean William Schlesinger of Duke’s Nicolas School to bring agricultural air quality to the forefront of national attention. And so far they have been very successful.
The main issues surround ammonia and its serious effects on air quality.
This summer, N.C. State co-hosted the first ever national conference on agricultural air quality, which took place in Potomac, Md., Chancellor James L. Oblinger gave an opening address along with Ralph Cicerone, president of the National Academy of Sciences.
“It’s an interesting interdisciplinary study across the spectrum all focusing on waste reduction,” Oblinger said about the focus of the conference. “This is what takes place when you bring all the best minds to focus on the challenge. It’s been gratifying because I think we have been very productive.”
So the problem is?
While many students and faculty are very aware of the environment in terms of global warming, agriculture lags far behind in people’s concerns.
“Our culture has thought of agriculture as an industry that is relatively green in its production,” Aneja said. “And by green I mean pollution free.”
But in actuality, agricultural emissions are serious and potentially detrimental to our air.
“I know that livestock produces a lot of methane and things like that, which affect the air,” Danny Voss, a freshman in English, said. “Large animals in large quantities, things of that nature, would cause poor [air] quality.”
Methane is a concern, but the largest interest about animal emissions is the nitrogen found in their excrements that pool in lagoons or are recycled as fertilizers. Man-made fertilizers also contain nitrogen, which forms into the compound ammonia that causes negative side effects.
Aneja identifies two major problems with ammonia.
First, once ammonia is absorbed into the atmosphere it is redistributed through rain onto crops and into waterways.
In some instances the redistribution of the ammonia can be helpful for crops by acting in its original purpose — as a fertilizer. But because the compound is basic it can also kill crops by overexposing it to the factor that is supposed to help.
Ammonia is also distributed into waterways which can kill not only plants, but also animals. For example, Hurricane Floyd caused a redistribution of ammonia from North Carolina hog farms into waterways promoting algae growth and suffocating fish. This in turn eliminated prey for eagles and osprey, according to Michael Tennesen’s 2006 article “The Crisis in Agricultural Air.”
The second major issue surrounds ammonia’s importance in creating fine particulate matter.
“Particulate matter is a pollutant which has a host of other consequences, including negative effects on human health,” Aneja said. “Ammonia is what we call a precursor to fine particulate matter formation. It is a very important ingredient. Before these operations came around there wasn’t any ammonia so you didn’t see particulant matter, but now you do. So that is a major consequence to atmospheric pollutant — something that wasn’t there before is there now.”
For people, fine particulant matter can negatively impact asthma and emphysema sufferers.
In North Carolina, the largest contributor to Aneja’s concerns are hogs and their by-products, but any commercial-sized farm creates similar problems.
“If you go to a hog farm that is eight or 10 barns — a commercial barn of 30,000 to 50,000 hogs — the waste goes into the lagoon. The waste and the feces and the urine are treated in the open, in a football field-sized place,” Aneja said. “And that leads to odor and it leads to gases that are being created and degradation that is coming out into the atmosphere.”
Animal waste is accountable for 40 percent of worldwide ammonia emissions, supported by the Jan. 17, 2006, edition of EOS — the largest circulating scientific magazine in the country published by the American Geophysical Union according to Aneja.
The culmination of efforts
The Workshop on Agricultural Air Quality: State of the Science took place June 5-8 and covered multidisciplinary interests about this new concern.
According to Aneja, the workshop was a real success.
“For the first time around the world scientists came to a workshop to discuss, debate, deliberate and focus on this emerging issue, which is a combination of environmental issues, policy issues, agriculture issues and regulatory issues which were all brought into sharp focus from 25 different countries,” he said.
One of the most important things to come out of the conference is the dialogue which determined the focuses needed to create the best science behind agricultural air quality.
Before the conference Aneja worked with Schlesinger and multiple graduate students to publish an article titled “Emerging National Research Needs for Agricultural Air Quality,” that outlined their vision for air quality in terms of science, policy and regulations, and made it available online and in hard copy to everyone attending the conference.
Currently, Aneja is still working through the 1,300 pages of scientific reports made available at the conference, but he hopes to have synthesized the data by January.
“The solution to pollution was dilution,” Aneja said. “But no longer.”