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Biomonitoring: EPA Needs to Coordinate Its Research Strategy and Clarify Its Authority to Obtain Biomonitoring Data

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Biomonitoring, which measures chemicals in people's tissues or body fluids, has shown that the U.S. population is widely exposed to chemicals used in everyday products. Some of these have the potential to cause cancer or birth defects. Moreover, children may be more vulnerable to harm from these chemicals than adults. The Environmental Protection Agency (EPA) is authorized under the Toxic Substances Control Act (TSCA) to control chemicals that pose unreasonable health risks. GAO was asked to review the (1) extent to which EPA incorporates information from biomonitoring studies into its assessments of chemicals, (2) steps that EPA has taken to improve the usefulness of biomonitoring data, and (3) extent to which EPA has the authority under TSCA to require chemical companies to develop and submit biomonitoring data to EPA."
Date: April 30, 2009
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Biomonitoring: EPA Could Make Better Use of Biomonitoring Data

Description: Testimony issued by the Government Accountability Office with an abstract that begins "Biomonitoring, which measures chemicals in people's tissues or body fluids, has shown that the U.S. population is widely exposed to chemicals used in everyday products. Some of these have the potential to cause cancer or birth defects. Moreover, children may be more vulnerable to harm from these chemicals than adults. The Environmental Protection Agency (EPA) is authorized under the Toxic Substances Control Act (TSCA) to control chemicals that pose unreasonable health risks. One crucial tool in this process is chemical risk assessment, which involves determining the extent to which populations will be exposed to a chemical and assessing how this exposure affects human health This testimony, based on GAO's prior work, reviews the (1) extent to which EPA incorporates information from biomonitoring studies into its assessments of chemicals, (2) steps that EPA has taken to improve the usefulness of biomonitoring data, and (3) extent to which EPA has the authority under TSCA to require chemical companies to develop and submit biomonitoring data to EPA."
Date: February 4, 2010
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Final Technical Report

Description: The Center of Excellence for Hazardous Materials Management award was used to establish the organization and initiate investigations of hazardous waste issues along the U.S.-Mexico border. Scientific investigations conducted during the execution of this grant contributed significant data and established new sampling protocols to the dimension, frequency and severity of hazardous materials (e.g., heavy metals) along the U.S.-Mexico border. Additionally, new protocols and assessments with distinct Homeland Security implications were embedded thus establishing a baseline that will be significant for related investigations in the future.
Date: December 28, 2009
Creator: Lynn, Douglas C. & Restani, Marco, Ph.D
Partner: UNT Libraries Government Documents Department

Integrating Long-Term Avian Studies with Planning and Adaptive Management: Department of Energy Lands as a Case Study.

Description: Long-term bio-monitoring of avian communities have been initiated, but they often lack a management component. Integration of the managers needs at an early stage is suggested as a means to increase the use of the data. Variation in community structure is important in understanding impacts. In addition, reference site must be carefully selected.
Date: October 1, 2000
Creator: Burger, J.
Partner: UNT Libraries Government Documents Department

Evaluation of City of Denton Sub-Watershed by Benthic Macroinvertebrate Field Experimental Approach

Description: In this study, two different field experiments were designed to assess the relative influence of urbanization on benthic communities. During spring and summer, four urban and one reference sites from Denton County, Texas were selected for benthic macroinvertebrate evaluation. Statistically significant differences in colonized benthic macroinvertebrate taxa on artificial substrates were observed among the four urban sites and the reference site. Oligochaetes and chironomids were the dominant taxa at all sites. Identification of chironomid larvae at the subfamily and genus level to detect differences between sites had higher statistical power than the evaluation based on total chironomids. At the reference site, Caenis, Cladotanytarsus, Orthocladius, and Ceratopogonidae were the dominant taxa, while the urban sites were dominated by Dero, Physella, Ancylidae, Chironomus, Dicrotendipes, Glyptotendipes, Polypedilum, Pseudochironomus, Stenochironomus, and Tanytarsus. These differences may have been dependent upon differences in hydrologic regime and water quality between sites. Significant differences (ANOVA, p < 0.01) in water quality parameters (alkalinity, hardness, nitrates, phosphates, chlorides, sulfates, calcium, magnesium, potassium, and triazine) were found among water samples collected from the reference and urban sites. During the transfer period, most of the Ephemeroptera and Trichoptera taxa and a few other taxa disappeared from artificial substrates that were colonized at the reference site and then moved to the urban sites. Also, local abundant taxa from the urban site significantly (t test, p < 0.05) increased in number on the transferred artificial substrates. Seasonal differences in colonization patterns were also observed between the spring and summer experimental periods, which indicate that temporal variation is equally important, as is the anthropogenic effect in benthic community evaluation. Field survival and growth experiments using Erpetogomphus designatus larvae were designed to detect differences between evaluated sites. Larvae were collected from the reference site, measured in the laboratory, and exposed at the urban sites for ...
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Date: August 2006
Creator: Mahato, Mahendra
Partner: UNT Libraries

Macroinvertebrate Community Structure as an Indicator of Watershed Health in the Upper Trinity River Basin, North Central Texas

Description: This study describes macroinvertebrate community structure and assesses its potential in detecting point and non-point sources of disturbance associated with rural and urban areas in the Upper Trinity River Basin. Geospatial techniques were used to quantify landuse within the watershed in a GIS. At rural sites near the headwaters of the Trinity River, collector-gathering burrowers that are adapted to minimal flow comprised the majority of taxa. Destinies of taxa compositions at downstream sites increased and shifted toward psammophilic and rheophilic invertebrates, including primarily collector-filtering clingers, that are characteristic of shifting sand habitats in large prairie rivers. Benthic community structure generally benefited from point source impacts including wastewater treatment plant effluents that maintained higher flow. Community indices were negatively associated with forest landuse and positively associated with urban landuse. Partial CCA determined that flow and landuse contributed equally to species dispersions. Comparisons with historical biomonitoring studies in upper Trinity River Basin indicate improved watershed health.
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Date: May 2000
Creator: Stephenson, Jaynie M.
Partner: UNT Libraries

Integrating GIS with Benthic Metrics: Calibrating a Biotic Index to Effectively Discriminate Stream Impacts in Urban Areas of the Blackland Prairie Eco-Region

Description: Rapid Bioassessment Protocols integrate a suite of community, population, and functional metrics, determined from the collection of benthic macroinvertebrates or fish, into a single assessment. This study was conducted in Dallas County Texas, an area located in the blackland prairie eco-region that is semi-arid and densely populated. The objectives of this research were to identify reference streams and propose a set of metrics that are best able to discriminate between differences in community structure due to natural variability from those caused by changes in water quality due to watershed impacts. Using geographic information systems, a total of nine watersheds, each representing a different mix of land uses, were chosen for evaluation. A total of 30 metrics commonly used in RBP protocols were calculated. Efficacy of these metrics to distinguish change was determined using several statistical techniques. Ten metrics were used to classify study area watersheds according to stream quality. Many trends, such as taxa presence along habitat quality gradients, were observed. These gradients coincided with expected responses of stream communities to landscape and habitat variables.
Date: December 2003
Creator: Earnest, Steven F. P.
Partner: UNT Libraries