Zoonotic Diseases—Fostering Awareness in Critical Audiences

Zoonotic diseases are infectious diseases that are shared between humans and other vertebrate animals. Extension professionals often serve as consultants and educators to individuals at high risk of zoonotic diseases, such as participants in 4-H livestock projects. Effective education about zoonotic diseases begins with an awareness of the multitude of challenges that health care professionals face in diagnosing zoonotic disease. This review describes the factors that influence diagnosis of these diseases, as well as potential methods that the Extension professional can use to convert those challenges into effective educational messages

History of contaminant inputs into Lake Mead derived from sediment cores

Assessing the changes in contaminant inputs (both organic and inorganic) over time is important in determining sources and sinks of these inputs. Variations in contaminant input were assessed in four sediment cores taken in 1998 from three different parts of Lake Mead (two from Las Vegas Bay and one from Overton Arm and Virgin Basin). Sediments were analyzed for major and trace elements, radionuclides, and organic compounds. Anthropogenic contaminant concentrations are greatest in Las Vegas Bay reflecting inputs from the Las Vegas urban area, although concentrations are low compared to sediment quality guidelines and to other USA lakes. One exception to this pattern was higher mercury concentrations in the Virgin Basin core. The Virgin Basin core is in the main body of the reservoir and is influenced by the hydrology of the Colorado River, which changed after completion of Glen Canyon Dam. Major- and trace-elements in the core show pronounced shifts in the early 1960s and, in many cases, gradually return to concentrations more typical of pre-1960s by the 1980s and 1990s, after the filling of Lake Powell upstream. The Overton Arm is the sub-basin least effected by anthropogenic contaminant inputs. Cores from Las Vegas Bay taken in 2007 were analyzed for emerging contaminants and although data are still preliminary, detections of musk fragrances have been found only in the upper 10 – 15 cm of the core, indicating that these compounds either degrade with time or have only been accumulating for the past 10 – 20 years

Development of a Bilingual Training Tool to Train Dairy Workers on the Prevention and Management of Non-Ambulatory Cows

Dairy cows at risk of becoming non-ambulatory or downers represent economic losses and animal well-being issues for the dairy industry. Colorado State University researchers and Extension faculty collaborated with Colorado\u27s dairy industry to create a training tool for the early identification and management of cows at risk of becoming downers on dairy operations. The training tool is a DVD that contains a short movie, a Power Point presentation, a quiz, and links to additional Web resources. All materials are available in English and Spanish to accommodate the language differences of the predominant cultural groups employed in the dairy industry

Zinc Isotopic Signatures in Eight Lake Sediment Cores from Across the United States

Zinc is an important trace element pollutant in urban environments; however, the extent of Zn contamination and the sources of urban Zn pollution are often unclear. We measured Zn concentrations and isotopes in sediment cores collected from eight lakes or reservoirs across the United States. We paired these data with historical records of land use within each watershed to calculate a mean Zn concentration and δ⁶⁶Zn for natural (less than 5% urban land use; 123 ± 21.7 mg/kg; +0.33 ± 0.08‰, <i>n</i> = 6 lakes) and urban (greater than 70% urban land use; 389 ± 200 mg/kg; +0.14 ± 0.07‰, <i>n</i> = 3 lakes) lake sediments. The relation between Zn concentration data and Zn isotope data allows us to create a mixing model between two end members: natural and urban. The δ⁶⁶Zn of the urban end-member is consistent with Zn pollution from vehicle-related sources (tire wear and emissions). Application of this model to samples collected from lakes recording periods ranging from 5 to 70% urban land use in their surrounding watersheds indicates that the lakes and reservoirs were affected by large amounts of Zn from urban sources

Zinc Isotopic Signatures in Eight Lake Sediment Cores from Across the United States

Zinc is an important trace element pollutant in urban environments; however, the extent of Zn contamination and the sources of urban Zn pollution are often unclear. We measured Zn concentrations and isotopes in sediment cores collected from eight lakes or reservoirs across the United States. We paired these data with historical records of land use within each watershed to calculate a mean Zn concentration and δ⁶⁶Zn for natural (less than 5% urban land use; 123 ± 21.7 mg/kg; +0.33 ± 0.08‰, <i>n</i> = 6 lakes) and urban (greater than 70% urban land use; 389 ± 200 mg/kg; +0.14 ± 0.07‰, <i>n</i> = 3 lakes) lake sediments. The relation between Zn concentration data and Zn isotope data allows us to create a mixing model between two end members: natural and urban. The δ⁶⁶Zn of the urban end-member is consistent with Zn pollution from vehicle-related sources (tire wear and emissions). Application of this model to samples collected from lakes recording periods ranging from 5 to 70% urban land use in their surrounding watersheds indicates that the lakes and reservoirs were affected by large amounts of Zn from urban sources

Identification of Contamination in a Lake Sediment Core Using Hg and Pb Isotopic Compositions, Lake Ballinger, Washington, USA

Concentrations and isotopic compositions of Hg and Pb were measured in a sediment core collected from Lake Ballinger, near Seattle, Washington, USA. Lake Ballinger has been affected by input of metal contaminants emitted from the Tacoma smelter, which operated from 1887 to 1986 and was located about 53 km south of the lake. Concentrations and loadings of Hg and Pb in Lake Ballinger increased by as much as three orders of magnitude during the period of smelting as compared to the pre-smelting period. Concentrations and loadings of Hg and Pb then decreased by about 55% and 75%, respectively, after smelting ended. Isotopic compositions of Hg changed considerably during the period of smelting (δ202Hg = -2.29‰ to -0.38‰, mean -1.23‰, n = 9) compared to the pre-smelting period (δ202Hg = -2.91‰ to -2.50‰, mean -2.75‰, n = 4). Variations were also observed in 206Pb/207Pb and 208Pb/207Pb isotopic compositions during these periods. Data for Δ199Hg and Δ201Hg indicate mass independent fractionation (MIF) of Hg isotopes in Lake Ballinger sediment during the smelting and post-smelting period and suggest MIF in the ore smelted, during the smelting process, or chemical modification at some point in the past. Negative values for Δ199Hg and Δ201Hg for the pre-smelting period are similar to those previously reported for soil, peat, and lichen, likely suggesting some component of atmospheric Hg. Variations in the concentrations and isotopic compositions of Hg and Pb were useful in tracing contaminant sources and the understanding of the depositional history of sedimentation in Lake Ballinger

Zn and Cu Isotopes As Tracers of Anthropogenic Contamination in a Sediment Core from an Urban Lake

In this work, we use stable Zn and Cu isotopes to identify the sources and timing of the deposition of these metals in a sediment core from Lake Ballinger near Seattle, Washington, USA. The base of the Lake Ballinger core predates settlement in the region, while the upper sections record the effects of atmospheric emissions from a nearby smelter and rapid urbanization of the watershed. δ66Zn and δ65Cu varied by 0.50‰ and 0.29‰, respectively, over the 500 year core record. Isotopic changes were correlated with the presmelter period (~1450 to 1900 with δ66Zn = +0.39‰ ± 0.09‰ and δ65Cu = +0.77‰ ± 0.06‰), period of smelter operation (1900 to 1985 with δ66Zn = +0.14 ± 0.06‰ and δ65Cu = +0.94 ± 0.10‰), and postsmelting/stable urban land use period (post 1985 with δ66Zn = 0.00 ± 0.10‰ and δ65Cu = +0.82‰ ± 0.12‰). Rapid early urbanization during the post World War II era increased metal loading to the lake but did not significantly alter the δ66Zn and δ65Cu, suggesting that increased metal loads during this time were derived mainly from mobilization of historically contaminated soils. Urban sources of Cu and Zn were dominant since the smelter closed in the 1980s, and the δ66Zn measured in tire samples suggests tire wear is a likely source of Zn

Water Quality in the Trinity River Basin, Texas, 1992-95 (USGS Circular 1171)

TextThis report is intended to summarize major findings that emerged between 1992 and 1995 from the water-quality assessment of the Trinity River Basin Study Unit and to relate these findings to water quality issues of regional and national concern. The information is primarily intended for those who are involved in water resource management.U.S. Department of the Interior, USGSCenter for Research in Water Resource