Solving Environmental Problems
Using Geospatial Analysis

Introduction

“Now I see it!” is a phrase that indicates successful communication and enlightenment. The ability to accomplish both with illustrations and maps is critical for making sense of otherwise dense and complicated technical data sets and analyses. In particular, powerful analytical tools such as advanced event-specific projection models (e.g., oil spill models), multi-media transport and fate models, and spatially-explicit wildlife exposure models, generate large and complex data sets that can be challenging to understand when presented only in tables of results without a clear geographical frame of reference. And maps alone do not do the trick.

Geospatial analyses using geographic information systems (GIS) have proven particularly helpful, offering useful visual displays of information together with underlying analytical power. GIS relies on digital maps, photographs, satellite images, and other visual media to capture user-specified geographic data. Using these base mapping and visualization tools, data sets are “overlaid” on the maps and can be presented, visualized, and analyzed in “layers.” Physical, chemical, and biological stresses on landscapes, watersheds, and coastal areas can be represented and viewed within a GIS framework and further analyzed with GIS tools. These tools can elucidate subtle changes that occur over time and that are manifested at particular spatial scales. Such information is critical for reconstructing the history of events, forecasting future trends, determining the causes of environmental problems, supporting other forensic analysis, and giving insight on possible solutions. In addition to its analytical capabilities, GIS can be used to communicate information to a broad audience. Most contemporary environmental assessment, problem-solving, and litigation support activities rely on a GIS tool as a central platform for analysis and presentation to stakeholders, including regulators, technical audiences, and juries. This enhances the utility of the underlying analyses and information for insurance cases, regulatory proceedings, voluntary environmental programs, and litigation. The versatility and value of GIS is illustrated by a variety of cases completed by our scientists over the past several years.

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The Ecological Effects of Nanomaterials: A Challenge for the Future

Nanomaterials are extremely small-scale engineered structures with at least one dimension less than or equal to100 nanometers (for reference, a nanometer equals one billionth of a meter). These materials are used or developed for numerous commercial purposes including use in semiconductors, personal care products, microelectronics, and medicines. In addition, because of their high reactivity and dispersibility, specialized nanoparticles such as nanoscale iron particles show promise in the field of environmental remediation. The unique physiochemical properties of nanomaterials that make them beneficial in these applications could also result in unexpected biological interactions. For example, when compared to larger scale forms, nanomaterials have a much larger surface area, potentially resulting in higher reactivity. Also, the smaller the particle, the longer it will remain in suspension, which may affect its environmental transport, bioavailability, and toxicity. For these reasons, it is likely that nanomaterials would affect aquatic and terrestrial organisms differently from larger scale materials. To date, very few ecotoxicity studies have been published on nanomaterials, and additional studies are needed to understand the potential for environmental effects.

Ecological receptors can be exposed to nanomaterials through inhalation, ingestion, passage across gills, passive transport, and cellular absorption. The focus of available studies has been on metal oxide particles, carbon nanotubes, and fullerenes. These initial studies have focused on high exposures to produce definite toxicity, resulting in various effects. In aquatic organisms, effects include oxidative deterioration of brain lipids, developmental and reproductive effects, effects on mobility, and lethality. Toxicity of nanoparticles has also been shown in the terrestrial environment, including crop root growth inhibition and lung damage in laboratory rodents. However, adverse effects have not been observed in all cases. For example, tests have shown that nano titanium dioxide promoted plant germination and growth, and relatively high soil concentrations of nano zinc oxide (levels up to 1,000 ppm in soil) were not toxic to earthworms. Studies are emerging that are beginning to define threshold levels for effects and relative differences in toxicity among nanomaterials. Nanoparticle behavior in environmental media (e.g., tendency to agglomerate, adhere to suspended solids or sediments) may also greatly limit actual toxicity in the environment. Additional research is needed to further understand nanomaterial uptake, toxicity, and ecological risks. Much of this research is being funded by U.S. EPA Science to Achieve Results (STAR) grants. STAR grants have been awarded to study the environmental and human health effects of engineered nanomaterials, and nanomaterials for use in environmental remediation. In 2006, 21 nanotechnology research grants were awarded for topics that included toxicology, fate, transport and transformation, bioavailability, human and ecological exposure, and life cycle assessment. These recent research solicitations include partnerships with the National Science Foundation (NSF), the Department of Energy (DOE), the National Institute for Occupational Safety and Health (NIOSH), and the National Institute of Environmental Health Sciences (NIEHS).

Nanotechnology industries and environmental managers are developing programs to consider the risks to human health and the environment as these new materials are increasingly being used and developed. In the next issue of Environmental Perspectives, we will more fully explore the state-of-the-science on the ecological effects of nanomaterials.

New Faces

Kirk O'Reilly, Ph.D.
Managing Scientist, Environmental
Bellevue, WA
Dr. Kirk O'Reilly is a Managing Scientist in Exponent's Environmental Sciences practice and is based in Bellevue, Washington. He has more than 20 years of experience investigating the interaction between environmental and biological chemistry, and spent 15 years as an in-house consultant for a major oil company. He is a recognized expert in bioremediation, environmental chemistry, and innovative remedial technologies, and played a significant role in developing the oil industry’s technical response to managing MTBE in the environment.

Dr. O'Reilly provided litigation support in toxic tort suits, and managed projects focused on the remediation of soils, sediments, and groundwater, as well as on improving industrial wastewater treatment. Treatment targets included crude oil, refined products, chlorinated solvents, wood treatment compounds, pesticides, and fertilizers. He developed innovative methods for monitoring the transformation and assessing the risk of petroleum. He has also conducted toxicity identification evaluations on refinery effluents. Experienced working within the constraints of the RCRA and NPDES programs, Dr. O’Reilly promotes the use of strategic site assessments to reduce costs while improving quality. He has participated in collaborative research projects with regulators at the federal, state, and local level, and taught technical courses sponsored by regulatory agencies, universities, and industrial trade groups. He is trained in administrative, environmental, and water law.

Recent/Upcoming Publications

Boehm, P.D., D.S. Page,
J.M. Neff, and C.B. Johnson. 2007. Potential for sea otter exposure to remnants of buried oil from the Exxon Valdez oil spill. Environ. Sci. Technol. A, DOI: 10.1021/es070829e.

Chan, W.R., and W.J. Shields. 2007. Deposition of dioxin in attics from backyard burning. Organohal. Comp. 69:722–725.

Chan, W., W. Nazaroff, P. Price, and A. Gadgil. 2007. Effectiveness of urban shelter-in-place–II: Residential districts. Atmos. Environ. (in press).

Mearns, A.J., D.J. Reish, P.S. Oshida, M. Buchman, T. Ginn, and R. Donnelly. 2007. Effects of pollution on marine organisms. Water Environ. Res. 79(10):2102–2160.

Levy, J. (ed.). 2007. Landmark opinions, perspectives on the Supreme Court’s NSR and climate change rulings. EM.

Murphy, B. 2007. Age-dating gasoline spills when information is limited. Environ. Foren. (8)3:199–204.

Shock, S.S., B.A. Bessinger, Y.W. Lowney, and J.L. Clark. 2007. Assessment of the solubility and bioaccessibility of barium and aluminum in soils affected by mine dust deposition. Environ. Sci. Technol. 41(13):4813–4820; (Article) DOI: 10.1021/es0703574.

Recent/Upcoming Conferences & Presentations

Nineteenth Annual Texas Environmental Superconference
Austin, TX
August 1–3, 2007
Global warming models: Strengths and weaknesses.
Levy, J.

American Bar Association Section of Environment, Energy, and Resources 15th Annual Section Meeting
Pittsburgh, PA
September 26–29, 2007

Assessing environmental liabilities of international legacy operations.
Bigham, G., and C. Menzie.

SETAC Hudson-Delaware Chapter Workshop on Environmental Risk Assessment of Metals and Metalloids
Camden, NJ
October 26, 2007

Mercury in the metals risk assessment framework.
Henry, B., G. Bigham, and C. Menzie.

Principles for metals risk assessment: U.S. EPA Framework.
Menzie, C.

SETAC North America 28th Annual Meeting
Milwaukee, WI
November 11–15, 2007

Soil lead risk for grit ingesting birds: A simple methodology to estimate the number of grit size lead particles in soils and sediment.
Kierski, M., C. Menzie, and E.A. Ferguson.

Dinitrotoluene and di-n­buytlphthalate exposure and effects evaluation for birds at Badger Army Ammunition Plant.
Kierski, M., C. Menzie, and C. Carroll.

Clutch morphology and the timing of exposure impact the susceptibility of aquatic insect eggs to esfenvalerate.
Johnson, K.R., P.C. Jepson, and J.J. Jenkins.

Variation in soot carbon-water partition coefficients: Native versus added PAHs.
Thorsen, W.A., and D. Shea.

Bioavailability of sediment-associated contaminants.
Session chairs:
Kane Driscoll, S., and J. Steevens.

Use of site-specific equilibrium partitioning sediment benchmarks for polycyclic aromatic hydrocarbon mixtures to predict toxicity of sediments at former manufactured gas plants.
Kane Driscoll, S.B., B. Amos, M.E. McArdle, C. Menzie, and A.J. Coleman.

Uncertainty plagues the decision’s quality. Interactive debate:
C. Menzie versus P. Calow.

The fiddly details of uncertainty—Mathematics, statistics, hypotheses. Interactive debate:
K. von Stackelberg versus Wayne Landis.

Lack of complete exposure pathways for metals in natural and FGD gypsum.
Yost, L., S.S. Shock, J.J. Noggle, Y. Lowney, S.E. Holm.

Evaluation of potential for mercury volatilization from gypsum products using flux chamber tests.
J.J. Noggle, S.S. Shock, N. Bloom, and L.J. Yost.

Using the target lipid model as an approach to assess tissue residues and the response of baseline toxicants in fish and aquatic invertebrates.
McElroy, A., M. Baron, S.K. Driscoll, T. Preuss, T. Parkerton, and J. Steevens.

AGU Fall Meeting
San Francisco, CA
December 10–14, 2007

Measurement of mercury concentrations in marsh drainages over a tidal cycle.
Henry, B., and G.N. Bigham.