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Full-Text Articles in Pharmacology, Toxicology and Environmental Health

Toxicity Of The Technology Critical Elements Germanium And Yttrium To Daphnia Magna And Hyalella Azteca And The Influence Of Toxicity Modifying Factors, Rashid Shah Jan 2022

Toxicity Of The Technology Critical Elements Germanium And Yttrium To Daphnia Magna And Hyalella Azteca And The Influence Of Toxicity Modifying Factors, Rashid Shah

Theses and Dissertations (Comprehensive)

Technology critical elements (TCEs) are increasingly used in high and green technologies but there is little aquatic toxicity data for TCEs, particularly in fresh water. The objective of this study was to investigate the toxicity of two TCEs, Ge and Y, to Daphnia magna and Hyalella azteca and to understand the role of natural organic matter and cations on toxicity modification. Testing followed standard methods. The 48 h EC50 for D. magna was 11.6 (95% CI of 9.64-13.8) mg Ge/L based on measured dissolved concentrations at test end. The addition of NOM at 10 mg DOC/L resulted in a significant …


Nickel And Copper Mixture Toxicity To Daphnia In Soft Water, Prachi Deshpande Jan 2016

Nickel And Copper Mixture Toxicity To Daphnia In Soft Water, Prachi Deshpande

Theses and Dissertations (Comprehensive)

Industrially important metals, such as Cu and Ni, sometimes are present at elevated concentrations in lakes, including those in the Sudbury, ON region. Although they are essential metals, their divalent-cation state (Cu2+ and Ni2+) can be toxic at high concentrations in the water. The free-ion toxicity of each of these metals has been studied in isolation, but rarely as a mixture. The economic importance of Cu2+ and Ni2+ makes them essential to study in the context of mixture toxicity. The objectives were to: (1) determine Cu and Ni mixture toxicity to Daphnia through acute LC50 …


Do Toxicity Modifying Factors Influence Acute Or Chronic Toxicity Of Thulium To Hyalella Azteca?, Alexandria H. Loveridge Jan 2016

Do Toxicity Modifying Factors Influence Acute Or Chronic Toxicity Of Thulium To Hyalella Azteca?, Alexandria H. Loveridge

Theses and Dissertations (Comprehensive)

The industrial demand for rare earth elements (REEs) is growing and as a result, environmental exposure is a concern. Very little is understood about the toxicity of REEs in aquatic environments. The objective of this research is to evaluate the acute and chronic toxicity of Tm and to also understand the toxicity modifying influence of dissolved organic matter (DOM) and cationic competition (Ca2+, Mg2+ and Na+). Furthermore, the aim of this study was to determine linkages between Tm bioaccumulation, growth and survival during chronic exposures. Standard methods (Environment Canada) were followed for both 96h acute and 14d chronic tests, in …


Carbon Nanomaterials In Freshwater Ecosystems: An Chronic, Multi-Generational, And Genomic Assessment Of Toxicity To Daphnia Magna, Devrah Anne Arndt May 2014

Carbon Nanomaterials In Freshwater Ecosystems: An Chronic, Multi-Generational, And Genomic Assessment Of Toxicity To Daphnia Magna, Devrah Anne Arndt

Theses and Dissertations

Carbon nanomaterials are synthesized with a variety of core structures and surface chemistries to make them more biocompatible for application in different industries, but variation in core structure and functionalization can change the toxicity of carbon nanomaterials to organisms. In addition, current literature is dominated by data from acute toxicity assays, but meta-data is necessary to improve our understanding of nanomaterial toxicity. This project identifies specific core structures and surface chemistries that make carbon nanomaterials more and less toxic using chronic toxicity assays and multi-generational assays to generate a dataset on the sub-lethal impacts of nanomaterials to Daphnia magna. In …


The Effects Of Sodium Lauryl Sulfate On The Abundance Of Producers And Grazers In Aquatic Communities Using Freshwater Microcosms, Stephanie R. Shipley Apr 2014

The Effects Of Sodium Lauryl Sulfate On The Abundance Of Producers And Grazers In Aquatic Communities Using Freshwater Microcosms, Stephanie R. Shipley

Honors College Theses

With increases in environmental awareness, industry has responded with products that reduce negative impacts on aquatic ecosystems. Sodium lauryl sulfate (SLS), a rapidly degrading chemical commonly found in cleaners labeled as ‘environmentally friendly,’ has been shown to have low toxicity in single species toxicity tests. However, that organisms have different sensitivities to SLS suggests a need for measuring effects at the community level. We exposed communities of microalgae (Chlorella sp.) and invertebrate grazers (a benthic snail, Elimia sp. and pelagic microcrustacean Daphnia magna) to 0, 0.5 or 1.5 mgL-1 SLS. Water quality and invertebrate abundance were measured …


Evaluating Acute Toxicity Of Cadmium To Chironomid Using Hemoglobin As A Molecular Biomarker, Jun Taek Oh Jan 2009

Evaluating Acute Toxicity Of Cadmium To Chironomid Using Hemoglobin As A Molecular Biomarker, Jun Taek Oh

Seton Hall University Dissertations and Theses (ETDs)

Effects of cadmium (Cd), a heavy metal contaminant, on hemoglobin were investigated in aquatic midge fly larvae of the Family, Chironomidae. In this study, chironomid populations from one polluted site, Kearny Marsh, New Jersey, two reference sites, North East Creek, and Bass Harbor, ME, and a laboratory population were taxonomically identified and tested for their sensitivity to Cd. Heavy metals in tissue, water and sediment were analyzed using Atomic Absorption Spectroscopy. Water quality at each site was assessed by measuring pH, dissolved oxygen (DO), oxidation-reduction potential ( eH), salinity and temperature. Hemoglobin proteins in individual larvae were easily detected using …


Effects Of Ethanol On The Toxicity And Metabolism Of Acetonitrile And Acrylonitrile, Nancy Ochoa-Garza Aug 2002

Effects Of Ethanol On The Toxicity And Metabolism Of Acetonitrile And Acrylonitrile, Nancy Ochoa-Garza

Theses and Dissertations - UTB/UTPA

This study examined the effects of ethanol on the toxicities and metabolism of two aliphatic nitriles: acetonitrile and acrylonitrile (one unsaturated and one saturated aliphatic nitrile, respectively) in male Sprague-Dawley rats at four different time intervals. Toxicity signs were apparent in all animals given the nitrile dosage, but those treated with ethanol dosages showed signs of toxicity earlier than those treated with glucose dosages. Both of the nitrites were metabolized to cyanide and thiocyanate. The concentration levels of each metabolite was apparent at 2 and 3 g/kg ethanol dosage for acetonitrile and 3 and 4.5 g/kg ethanol dosage for acrylonitrile …