Public Release:  Spring rains bring life to Midwest granaries but foster Gulf of Mexico 'Dead Zone'

American Chemical Society

NEW ORLEANS, April 9, 2013 -- The most serious ongoing water pollution problem in the Gulf of Mexico originates not from oil rigs, as many people believe, but rainstorms and fields of corn and soybeans a thousand miles away in the Midwest. An expert on that problem -- the infamous Gulf of Mexico "Dead Zone" -- today called for greater awareness of the connections between rainfall and agriculture in the Midwest and the increasingly severe water quality problems in the gulf.

Keynoting a symposium at the 245th National Meeting & Exposition of the American Chemical Society, the world's largest scientific society, Nancy N. Rabalais, Ph.D., emphasized that oil spills like the 2010 Deepwater Horizon disaster, claim a terrible toll. Sometimes, however, they overshadow the underlying water pollution problem that has been growing more and more severe for almost 40 years.

"The Dead Zone is a vast expanse of water, sometimes as large as the state of Massachusetts, that has so little oxygen that fish, shellfish and other marine life cannot survive," Rabalais explained. "The oxygen disappears as a result of fertilizer that washes off farm fields in the Midwest into the Mississippi River. Just as fertilizer makes corn and soybeans grow, it stimulates the growth of plants in the water -- algae in the Gulf. The algae bloom and eventually die and decay, removing oxygen from the water. The result is water too oxygen-depleted to support life."

An oceanographer and executive director of the Louisiana Universities Marine Consortium, Rabalais spoke at a special symposium organized by 2012 ACS President Bassam Z. Shakhashiri, Ph.D. Abstracts of other presentations in the event, titled "Water: A Grand Challenge for Science and Society," appear below.

"Shortages in availability of water suitable for drinking, agriculture and industry are the common denominator in some of the great global challenges facing society in the 21st century," Shakhashiri said. "More than 1 billion people already lack access to reliable supplies of clean water. Climate change, surging population growth and other factors stand to make matters worse. I hope this symposium helps engage scientists in seeking solutions that help sustain Earth and its people."

Rabalais described how the Dead Zone is getting larger and more desolate, with lower concentrations of oxygen dissolved in the water. The Gulf also seems to be more sensitive to the nitrogen and phosphorous fertilizers that wash down the Mississippi River and the Atchafalaya River today than it was in the past. Concentrations of fertilizer that caused a relatively small amount of oxygen depletion now are having a more profound effect.

Fish and shellfish either leave the oxygen-depleted water or die, causing losses to commercial and sports fisheries in the Gulf, she noted. Dead fish sometimes wash up onto beaches, with a negative impact on recreational activities and tourism.

Oil spills and other local pollution compound those negative effects on marine life, Rabalais noted. By day 77 of the Deepwater Horizon disaster, for instance, the oil slick had covered about one-third of the Dead Zone, making it even more inhospitable.

The amounts of phosphorus fertilizer compounds in the Lower Mississippi have doubled and nitrogen compounds have tripled nitrogen over the last 50 years, Rabalais said. Oxygen levels in the Dead Zone have declined in parallel.

Rabalais pointed out that advances in chemistry and other fields do promise solutions. Fertilizers that stay in the soil and resist runoff, for instance, could have a big impact. Genetically modifying crops so that they produce some of their own fertilizer could also help with the problem.

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Abstracts

Water is life and is to be celebrated

Nancy N. Rabalais, Ph.D., Louisiana Universities Marine Consortium, 8124 Highway 56, Chauvin, LA, 70344, United States, 985-851-2801, nrabalais@lumcon.edu

Every day I do, but I annually bring water from the Gulf of Mexico dead zone to a water ceremony at the Unitarian church in Baton Rouge where it is combined with waters from others from all over the world and locally. Some of the water is retained in the urn for the next year's ceremony. Each year I bring my intent to continue to work for water quality in the Mississippi River watershed and its coastal ocean. The distances and seeming disconnects are large, but surprisingly short for a drop of water from the Gulf of Mexico to be transported inland and then flow with other droplets down the river to the ocean.

The imperative science needs for health-related water research and education

Joan B. Rose, Ph.D., Michigan State University, Department of Fisheries and Wildlife, 480 Wilson Road, Natural Resources Bldg Rm 13, East Lansing, MI, 48824, United States , 517-432-4412, rosejo@msu.edu

Linking advances in genomics research, mathematics and earth sciences as well as novel engineering technologies is imperative in order to create a future of globally safe water. To address the major challenges in managing the growing amounts of animal and human waste water pollution; protecting water resources and restoring an economically vital coastline, we will need to invest in the characterization of our water microbiological communities and shift the pollution science paradigm toward an understanding of risk and resilience under global change.

Water sustainability in a changing world

Jerald L. Schnoor, Ph.D., The University of Iowa, Department of Civil and Environmental Engineering, The University of Iowa, Iowa City, Iowa, 52242, United States , 319-335-5649, jschnoor@engineering.uiowa.edu

Water is a vital renewable resource for society which is increasingly stressed by multiple demands for water supply, agriculture, industry, recreation, and ecosystem needs. Changes in water supply and demands for water are driven by population growth, climate and land use change, and our energy choices (such as biofuels, oil sands, and shale gas). In this talk, we discuss the drivers affecting water sustainability and potential solutions including: adapting to a changing water world, direct and indirect potable water reuse, resilient water infrastructure, and more holistic management of the water cycle. This paper also describes research at Clear Creek watershed (270 km2), a tributary of the Iowa River in eastern Iowa, to create an environmental observing facility and intelligent digital watershed (IDW) for better water management and prediction.

Future of urban water systems: Technological and institutional challenges

David Sedlak, Ph.D., University California, Berkeley, Department of Civil and Environmental Engineering, 657 Davis Hall, University of California, Berkeley, Berkeley, CA, 94720, United States , 510-643-0256, sedlak@berkeley.edu

The complex infrastructure that cities rely upon for water supply, treatment and drainage are struggling to keep up with the combined effects of climate change, population growth, underinvestment in maintenance and a growing recognition of the impacts of contaminants that cannot be removed easily by existing treatment processes. Technological solutions to these problems that employ the latest developments in materials science, chemistry, biology and electronics are capable of greatly enhancing the performance of these systems. However, the success of these next generation technologies will depend upon their integration into the institutions responsible for urban water management.

Convergence of nanotechnology and microbiology: Emerging opportunities for water disinfection, integrated urban water management, and risk assessment

Pedro J. Alvarez, Ph.D., Rice University, Department of Civil and Environmental Engineering, 6100 Main Street, MS 519, Houston, TX, 77005, United States , 713-348-5903, alvarez@rice.edu

The extraordinary properties of some nanomaterials offer leapfrogging opportunities to develop next-generation applications for drinking water disinfection and safer wastewater reuse (e.g., photocatalytically-enhanced disinfection, biofouling-resistant membranes, and biofilm- and corrosion-resistant surfaces). The multifunctional and high-efficiency processes enabled by nanotechnology are broadly applicable in both industrialized and developing countries, by enabling the retrofitting of aging infrastructure and the development of high performance point-of-use devices that facilitate differential water treatment and reuse. On the other hand, the use of nanomaterials in commercial products is outpacing the development of knowledge and regulations to mitigate potential risks associated with their release to the environment. Therefore, it is important to understand how engineered nanoparticles interact with microorganisms, which form the basis of all known ecosystems and provide critical environmental services such as nitrogen cycling. The convergence of nanotechnology with environmental microbiology could expand the limits of technology, enhance global health through safer water reuse, and contribute towards sustainable and integrated water management. This presentation will consider the antibacterial mechanisms of various nanomaterials within the context of environmental implications and applications. Research needs to steward ecologically responsible nanotechnology will also be discussed.

Confronting the water challenge: Dow technologies increase the flow

William F. Banholzer, Ph.D., The Dow Chemical Company, Executive Department, 2030 Dow Center, Midland, MI, 48674, United States , 989-636-0718, mbiehler@dow.com

Dow is a leader in purification, separation and chemical technology, with a longstanding legacy of technology innovation for improving water quality and utilization. Communities throughout the world depend on Dow reverse osmosis membrane technology for desalination and water reclamation. Dow has also made investments that are solving the water-borne disease crisis by bringing affordable, potable water through deployment of low-cost, community-based water systems. In addition, new processes for chemical production have been deployed that dramatically reduce wastewater production, helping to preserve freshwater resources.

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