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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 …


The Chronic Toxicity Of Titanium Dioxide Nanoparticles To The Freshwater Amphipod Hyalella Azteca, Gurkirpal S. Malhi Jan 2012

The Chronic Toxicity Of Titanium Dioxide Nanoparticles To The Freshwater Amphipod Hyalella Azteca, Gurkirpal S. Malhi

Theses and Dissertations (Comprehensive)

There has been an increased use of metal-oxide nanoparticles in both commercial and consumer products. The use of these products and waste generated during manufacture may ultimately be released into the aquatic environment and the potential for these contaminants to cause impacts must be assessed. This study examines the effect of titanium dioxide (TiO2) nanoparticles (NPs) on Hyalella azteca. Chronic toxicity exposures were conducted in 400mL of spiked test solution and contained 20 neonates. Samples collected for characterization of Ti in TiO2 NP exposure solutions were digested using ammonium persulfate as an oxidizing agent and dissolved …