Life Sciences Commons^™

Contaminants Of Emerging Concern: Effects Of Known Neuroactive Agents, Antibiotics, And Chemically Uncharacterized Photodegredates On Behavior And Physiology Of Daphnia Pulex, Vibhuti Matta

Wayne State University Theses

Emerging contaminants such as pharmaceuticals and personal care products (PPCPs), herbicides, pesticides, plasticizers, fire retardants, polycyclic aromatic hydrocarbons (PAHs), and other organic waste are increasingly being detected in surface water and ground water. These contaminants can enter into the environment through wastewater treatment plant effluent and agriculture runoff. Many of these emerging contaminants tend to be biologically active at very low concentrations, typically occur in water as part of complex mixtures, and may impact biota at concentrations not detected using traditional toxicity tests (e.g. LC 50 tests).

This study focuses on utilizing novel Daphnid optical bioassays to examine the toxicity …

Species - Dependent Cardiac And Motor Responses To Cholinergic Stimulation In Daphnia Pulex And Daphnia Magna, Bryan James Hannan

Wayne State University Theses

The role of acetylcholine (ACh) in regulating the activity of the heart and `feeding current' driven by the beating thoracic appendages of Daphnia pulex and Daphnia magna was evaluated using acetylcholinesterase inhibitors (AChE-I) and muscarinic receptor agonists. Single animals, tethered to a stainless steel pin, were tested in a watertight aquatic chamber that allowed free movement of appendages and swimming antennae. Heart contraction rate and the rate of thoracic appendage beating were quantified optically by measuring fluctuating changes in light-intensity caused by movement. Physostigmine, neostigmine, oxotremorine, pilocarpine as well as nicotine were used to study ACh and AChE. Atropine was …