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Effects of Triclosan, Triclocarban, and Caffeine Exposure on the Development of Amphibian Larvae.

Description: Triclosan and triclocarban are antimicrobials found in numerous consumer products, while caffeine is the most commonly consumed stimulant by humans. This study was undertaken to determine the effects of triclosan, triclocarban, and caffeine on the development and physiology of amphibian larvae. LC50 values of triclosan and triclocarban were determined after 96 hours for three North American larval species: Acris crepitans blanchardii, Bufo woodhousii woodhousii, Rana sphenocephala, and for a common amphibian developmental model: Xenopus laevis. Amphibian larvae were most sensitive to triclosan and triclocarban exposure during early development based upon 96-hour LC50 values. Heart rates for X. laevis and North American larvae exposed to triclosan were variable throughout development. However, significantly lower heart rates were observed in all larvae exposed to triclocarban. Metabolic rates of X. laevis and R. sphenocephala larvae exposed to triclosan were significantly affected in larvae exposed to ½ LC50 and the LC50 concentration. Metabolic rates of X. laevis larvae exposed to triclocarban were significantly affected by exposure to ½ LC50 concentrations in three of four stages investigated. No significant differences were observed in North American larvae exposed to triclocarban. Tissue uptake, lipid uptake, tissue bioconcentration factor (BCF) and lipid BCF of triclosan and triclocarban were investigated in three developmental stages of X. laevis, and in one developmental stage of B. woodhousii woodhousii, and R. sphenocephala. For most tissue and lipid uptake values, a significant increase was observed as exposure concentration increased. Tissue and lipid BCF values were dependent upon both stage and species. Chronic and acute effects of caffeine were determined in X. laevis larvae. Acute 96-hour LC50 values in four developmental stages were > 75,000 ug L-1 caffeine and heart rates were significantly different at the two earliest developmental stages. Larvae chronically exposed to caffeine reached metamorphosis at the same time as controls. Changes in ...
Date: August 2009
Creator: Palenske, Nicole Marie
Partner: UNT Libraries

Effects of Methanol, Atrazine, and Copper on the Ultrastructure of Pseudokirchneriella Subcapitata (Selenastrum Capricornutum).

Description: The toxicity of methanol, atrazine, and copper to Pseudokirchneriella subcapitata (Korshikov) Hindák historically referred to as Selenastrum capricornutum Printz were determined following 96 hrs growth in a modified Goram's growth media. Methanol and atrazine inhibited fluorescence readings in the cultures by 50% (IC50) at concentrations of 2% and 82 µg/l respectively. These toxicity values compared favorably to other published reports. The IC50 for copper was 160 µg/l which is substantially higher than reported values. This is understandable because of the high chelating capacity of Goram's media. The use of stereologically derived relative volume in the chloroplasts, mitochondria, lipid bodies, phosphate bodies, and nucleus was investigated to determine if it could be used as a sensitive endpoint in toxicity tests. The volume fractions for the chloroplasts and mitochondria were normally distributed in control cells while the nuclei, phosphate bodies, and lipid bodies were not. The chloroplasts were the most dominate organelle occupying a mean relative volume of 46% and mitochondria occupied a mean relative volume of 3%. The nucleus and phosphate bodies occupied a median relative volume of 7% and 2% respectively. The lipid bodies were rare in section profile and no meaningful median relative volume could be calculated. Up to the 82nd percentile of sectioned profiles contained no recognizable lipid bodies. The use of relative volume was not a sensitive endpoint for use in toxicity tests. No significant differences in relative volume could be detected in the nucleus or phosphate bodies following any treatment. Limited differences were detected in the mitochondria, chloroplasts, and lipid bodies. The only significant differences that appear to be biologically significant occurred in methanol treated cells where an increase in the lipid bodies' relative volume was apparently concentration dependent. Significant differences in the relative volume of mitochondria and chloroplasts do not appear to be biologically significant.
Date: May 2004
Creator: Garrett, David C.
Partner: UNT Libraries

[News Script: Defendant drugged, hearing postponed]

Description: Script from the WBAP-TV station in Fort Worth, Texas, covering a news story about the postponing of the trial of Joseph D'Angelo, accused of raping an 11-year-old Dallas girl, due to his being given paraldehyde as a sedative in his cell beforehand.
Date: April 9, 1956
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Suppression of immune functions by PCBs in the earthworm Lumbricus terrestris

Description: This research is part of an effort to develop non-mammalian surrogate immunoessays with the earth worm Lumbricus terrestris to assess immunotoxic potential of xenobiotics to mammals. The objective was to determine if earthworm immunoessays, namely E- and S- rosette formation and phagocytosis, are sensitive to a known mammalian immunotoxin, the PCB Arclor 1254.
Date: May 1989
Creator: Rodriguez Grau, Jorge Luis
Partner: UNT Libraries

The State of the Hudson 2009

Description: This report describes the environmental quality of the Hudson River and its watershed, including issues such as pollution, population growth, and biodiversity. The report also describes the habitats of estuaries, watersheds, and rivers in general.
Date: 2009
Creator: New York (State). Hudson River Estuary Program.
Partner: UNT Libraries

Great Lakes Restoration Initiative Action Plan

Description: This action plan articulates the most significant ecosystem problems for the Great Lakes, and describes efforts to address them. The five areas are toxic substances, invasive species, health and pollution, wildlife and habitat preservation and restoration, and finally a component that covers accountability and evaluation.
Date: February 21, 2010
Creator: United States. Council on Environmental Quality.
Partner: UNT Libraries

Environmental Agents Control Act

Description: The government of the Republic of China (Taiwan) passed this law to protect the environment and human health from harm by toxic chemicals or microbial preparations, including pesticides, fungicides, as well as certain synthetic chemicals.
Date: unknown
Creator: China (Republic : 1949- ). Huan jing bao hu shu
Partner: UNT Libraries

Drinking Water Management Act

Description: This law was passed by the Republic of China (Taiwan) to safeguard public health by protecting drinking water resources from pollution by dumping, logging, industry, nuclear waste, ranching, recreation, mineral exploration and extraction, transportation, and other activities.
Date: January 27, 2006
Creator: China (Republic : 1949- ). Huan jing bao hu shu
Partner: UNT Libraries

Toxic Chemical Substances Control Act

Description: This law was passed by the government of the Republic of China (Taiwan) to protect human health and the environment by controlling the production and handling of toxic chemicals.
Date: January 3, 2007
Creator: China (Republic : 1949- ). Huan jing bao hu shu
Partner: UNT Libraries

Clearing the Waters: A focus on water quality solutions

Description: This report discusses global water issues and offers a variety of proposals for countering the degradation of freshwater ecosystems for the benefit of public health and the environment.
Date: March 2010
Creator: Palanaippan, Meena; Gleick, Peter H.; Allen, Lucy; Cohen, Michael J.; Christian-Smith, Juliet; Smith, Courtney et al.
Partner: UNT Libraries

Dust from Africa Leads to Large Toxic Algae Blooms in Gulf of Mexico, Study Finds. [Press release].

Description: This press release summarizes the findings of a new study. Saharan dust clouds travel thousands of miles and fertilize the water off the West Florida coast with iron, which kicks off blooms of toxic algae. The research was partially funded by a NASA grant as part of ECOHAB: Florida (Ecology and Oceanography of Harmful Algal Blooms), a multi-disciplinary research project designed to study harmful algae.
Date: August 28, 2001
Creator: NASA News
Partner: UNT Libraries

How Healthy is the Upper Trinity River?: Biological and Water Quality Perspectives

Description: This conference report contains discussions and papers from a symposium hosted at Texas Christian University, in Fort Worth, Texas, examining the ecological health of the Upper Trinity River, and the impacts of various human activity, such as agriculture, urbanization, and waste management. The papers cover the effect of water quality on urban rivers, long-term water quality trends in the Trinity River, solutions that may improve water quality in the river, as well as biological, agricultural and waste-water issues.
Date: 1990
Creator: Jensen, Ric
Partner: UNT Libraries

A Water Quality and Ecological Survey of the Trinity River, Volume 2

Description: This volume of the report represents the technical findings of a study conducted on the ecological makeup of the Trinity River. The data presented includes: ambient toxicity test results and survival rates, United States Geological Survey (USGS) flow data, water quality data, as well as sediment quality data.
Date: November 1989
Creator: University of North Texas. Institute of Applied Sciences.
Partner: UNT Institute of Applied Sciences

Biodegradation of Certain Petroleum Product Contaminants in Soil and Water By Selected Bacteria

Description: Soil contamination by gasoline underground storage tanks is a critical environmental problem. The results herein show that in situ bioremediation using indigenous soil microorganisms is the method of choice. Five sites were selected for bioremediation based on the levels of benzene, toluene, ethylbenzene and xylene and the amount of total petroleum hydrocarbons in the soil. Bacteria capable of degrading these contaminants were selected from the contaminated sites and grown in 1,200 I mass cultures. These were added to the soil together with nutrients, water and air via PVC pipes.
Date: December 1995
Creator: Nevárez-Moorillón, Guadalupe Virginia
Partner: UNT Libraries

Effect of pH on the persistence and toxicity of cyfluthrin to Chironomus tentans

Description: The effect of pH upon the aquatic toxicity of cyfluthrin was determined in 48 h static acute toxicity tests using 2nd instar Chironomus tentans larvae. Tests were conducted in both dechlorinated tap water and lake water of pH 8.0, 7.2, and 6.6. After 48 h, immobilized and dead larvae were removed and replaced with 2nd instar larvae to assess the persistence of toxicity. Midges were cultured in water adjusted to the pH values used in testing.
Date: May 1992
Creator: Hambleton, Faith Ann (Faith Ann Elizabeth)
Partner: UNT Libraries

Toxicological assessment studies of the in vitro and in vivo effects of methyl 2-chloro-2-propenoate [methyl (α)-chloroacrylate]

Description: the toxic effects resulting from acrylic monomer exposure can pose as occupational risk factors for those involved in the manufacture, distribution, and use of the monomer and as potential risk factors for those accidentally exposed. This study is a toxicological assessment of the in vivo (intact animal) and in vitro (isolated human cell culture) responses to acute methyl (α)-chloroacrylate (MCA) exposure.
Date: August 1984
Creator: McClure, Fred Leland
Partner: UNT Libraries

[News Clip: Chemicals]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 10 P.M.
Date: June 9, 1980
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections