Environmental Sciences and Engineering

SwRI provides engineering and scientific services to industry and government to address challenging environmental problems and to monitor the environmental impact of hazardous operations. The Institute continues to conduct environmental monitoring and laboratory analysis for several U.S. demilitarization facilities. Staff members also perform applied engineering research, assess major health and environmental risks, and develop new sampling and analytical methods. During 2001, the Institute's environmental sciences and engineering contract research and development services were certified for ISO 9002 standards.

SwRI has supported several U.S. Army programs to incinerate nearly 30,000 tons of stockpiled chemical weapons. Since 1986, staff members have provided environmental monitoring support at the Johnston Atoll Chemical Agent Disposal System (JACADS) in the Pacific. As the facility entered its final closure phase, reliable analytical methods were lacking to verify there were no residual agents. The Institute developed methods to extract and analyze samples using charcoal filter banks, concrete, coral, and water for low-level agent contamination. These methods were important for verifying decontamination of chemical agents and their corresponding breakdown products. Previous analytical methods were long and tedious, used large solvent quantities, and had poor accuracy. The SwRI method is time efficient, consistently achieves low parts-per-billion detection limits, and uses instrumentation currently onsite.

For 10 years the Institute has studied pesticide concentrations in house dust. The Institute has participated in several studies across the United States to investigate and correlate the levels and impact of pesticides found in the home.

SwRI supported the U.S. Army Program Manager for Assembled Chemical Weapons Assessment in developing alternatives to the incineration of chemical warfare agents. Institute scientists evaluated analytical methods for measuring chemical agents in a process gas stream comprised of a mixture of hydrogen, methane, phosphine, and hydrogen sulfide generated under varied moisture and temperature conditions. SwRI developed methods to monitor chemical agents at parts per trillion levels within this environment. This required that monitoring equipment be reconfigured to accommodate the hydrogen atmosphere without creating an explosion risk due to the high concentration of hydrogen in the sampled gas. SwRI countered problems with the hydrogen sulfide and phosphine, components of the gas stream which were reactive with the chemical agents and/or the sample collection media, with unique sampling techniques.

SwRI is conducting comprehensive environmental monitoring for the U.S. Army as it prepares to incinerate the chemical agent stockpiles at the Umatilla Chemical Agent Disposal Facility in northeast Oregon. In its third year of a baseline period prior to facility operation, SwRI staff members continue to monitor selected organic and inorganic environmental pollutants up to 50 miles beyond the facility. Soil is collected at 25 sites. Vegetation, invertebrates, and small mammals are also collected at 19 locations, and water is collected at four sites. The monitoring program will continue during facility operations and for at least one year after completion of hazardous waste treatment operations.

Dogs were trained to detect the presence of a common, volatile compound to determine an effective working threshold amount for the reference material. SwRI provided standardized training aids and environmental monitoring to confirm the presence and amount of the substance.

SwRI supported Lackland Air Force Base in San Antonio in a program to train dogs to detect a reference compound. The canines were trained to detect the presence of a common, volatile compound with low toxicity. The Institute provided environmental monitoring of the compound, furnished training aids containing the target compound, and helped optimize and standardize the testing and analytical procedures. These steps helped to ensure that the dogs detected the target compound and not environmental factors or artifacts from the testing. The dogs successfully detected the substance at low levels (approximately one part per billion) -- near the detection limit of the monitoring instrumentation. The Institute helped design a discrimination study that would further refine the ability of the dogs to detect a single compound over other similar substances.

The Institute continues its collaboration with the National Cancer Institute, Silent Spring Institute, University of North Carolina, Mt. Sinai School of Medicine, and the Environmental Protection Agency (EPA) in studies on non-Hodgkin's lymphoma, breast cancer, and pesticide exposure. These studies measure the concentration of common pesticides and polycyclic aromatic hydrocarbons (PAHs) in house dust. Samples were collected from seven locations across the country in Los Angeles County, the Detroit area, the state of Iowa, the Seattle area, Yuma County (Arizona), Cape Cod (Massachusetts), and Long Island. Institute scientists prepared the complex dust samples and analyzed for low-level pesticides and PAHs. In samples collected from 1996 to 1999, all seven locations had the same prevalent pesticides: permethrin, chlorpyrifos, carbaryl, propoxur, ortho-phenylphenol, methoxychlor, DDT, chlordane, and diazinon. The concentrations of permethrin and many other current use pesticides were higher in Los Angeles and Cape Cod than at the other five sites. Dust from Long Island carried the highest levels of PAHs.

A number of environmental pollutants such as dioxin, polychlorinated biphenyls, polycyclic aromatic hydrocarbons (PAHs), and N,N-dimethylamine are extremely toxic at trace levels. SwRI developed a unique clean-up process that allows the detection of PAHs at levels 10 to 20 times lower than other analytical laboratories even from difficult matrices, such as oils and tissue samples. Facilities are equipped with three state-of-the-art, high-resolution gas chromatographs/high-resolution mass spectrometers that are not only extremely sensitive but also specific in detecting the selected target pollutants. Dioxin can be detected in as little as one part per trillion in soil and five parts per quadrillion in water.

The Institute teamed with Columbia University in two separate studies to assess the inhalation exposure of pregnant women in New York City and Poland to nine PAHs and 11 pesticides. These studies are investigating the effect of prenatal exposures on brain and mental development. SwRI scientists performed simulation experiments on personal and indoor air samples to evaluate the ability of filtered polyurethane foam (PUF) to retain pesticides and PAHs during air sampling. These experiments demonstrated that the target pesticides and PAHs are retained by PUF plugs and can be measured quantitatively in personal and indoor air at the sampling rates used while allowing at least 90 days of frozen storage before extraction.

Increased concerns about methyl mercury, which can affect the central nervous system after long periods of exposure, has spurred the need for improved extraction and analytical methods for the quantitation of methyl mercury at low levels in environmental soil, water, sewage, marine sediment, and biota. If left in the environment, metallic mercury converts to the toxic form methyl mercury. During the past year, SwRI scientists were challenged to enhance techniques that increase extraction efficiencies in various matrices. In a recent study, SwRI analyzed methyl mercury in frog tissues, a mid-level food chain indicator of this contaminant. To meet the new analytical requirements, an atomic absorption spectrophotometer was modified to quantitate methyl mercury at the low (parts-per-trillion) level.

2001 Annual Report SwRI Home