Evaluating the Life-History Responses of Adult Invasive (Bithynia tentaculata) and Native (Physa gyrina) Snails Exposed to a Cu-Based Pesticide (EarthTec® QZ).

The faucet snail, Bithynia tentaculata, is an invasive snail that facilitates outbreaks of waterfowl disease in the Upper Mississippi River of the United States. In response, there is interest in identifying strategies that mitigate its population and spread. In this study we assessed the effects of a copper (Cu) molluscicide, EarthTec® QZ, at three concentrations (0, 0.

A Pilot Evaluation of the Toxicity of EarthTec® QZ on Invasive (Bithynia tentaculata) and Native (Physa gyrina) Snail Species from the Upper Mississippi River.

We used a comparative approach to investigate the effects of a copper-based pesticide (EarthTec® QZ) on embryos of an invasive snail (Bithynia tentaculata) and a native snail (Physa gyrina). Embryos were exposed to one of three treatments: control (0 mg/L Cu), low-dose (0.1 mg/L Cu), or high-dose (0.

Developmental Toxicity of Triclosan in the Presence of Dissolved Organic Carbon: Moving Beyond Standard Acute Toxicity Assays to Understand Ecotoxicological Risk.

Triclosan (TCS) is an ionizable synthetic antimicrobial that has been found to be a persistent environmental contaminant with potential for bioaccumulation. Standard laboratory assays have shown that TCS is toxic to aquatic organisms; however, varied environmental conditions could impact this risk. For example, we would predict that sorption to dissolved organic carbon (DOC) in natural surface waters would reduce the bioavailability and, therefore, toxicity of TCS.

Probing the primary mechanisms affecting the environmental distribution of estrogen and androgen isomers.

Land application of animal manure has been identified as a source of natural and synthetic hormone contaminants that are frequently detected down-gradient of agricultural operations. Much research on the environmental fate of hormones has focused on the structural isomers most biologically active in mammals, e.g.

Ciprofloxacin sorption by dissolved organic carbon from reference and bio-waste materials.

Amphoteric pharmaceuticals are released to the environment in treated wastewater, medicated aquaculture feed, and through land disposal of livestock wastes and municipal biosolids. These wastes are rich in dissolved organic carbon (DOC), which may bind and potentially enhance pharmaceutical transport in the environment. To assess this potential, the antimicrobial ciprofloxacin (CIP) was chosen as a model amphoteric pharmaceutical to quantify DOC-water sorption coefficients (K(doc), L kg(-1)DOC) for four reference humic materials with varying chemical properties, digested and undigested municipal biosolids, treated municipal wastewater, and beef lagoon wastewater.

Partitioning of fluorotelomer alcohols to octanol and different sources of dissolved organic carbon.

Interest in the environmental fate of fluorotelomer alcohols (FTOHs) has spurred efforts to understand their equilibrium partitioning behavior. Experimentally determined partition coefficients for FTOHs between soil/water and air/water have been reported, but direct measurements of partition coefficients for dissolved organic carbon (DOC)/water (K(doc)) and octanol/ water(K(ow)) have been lacking. Here we measured the partitioning of 8:2 and 6:2 FTOH between one or more types of DOC and water using enhanced solubility or dialysis bag techniques, and also quantified K(ow) values for 4:2 to 8:2 FTOH using a batch equilibration method.

Combined effects of a herbicide (atrazine) and predation on the life history of a pond snail, Physa gyrina.

We investigated the combined effects of chronic pesticide exposure and predation on the life-history traits of Physa gyrina. Results show that atrazine and predation can impact snail immune function, reproduction, and survival. This work emphasizes the need to assess sublethal life-history responses to multiple stressors over biologically relevant timescales.

Soil microbial community responses to additions of organic carbon substrates and heavy metals (Pb and Cr).

Microcosm experiments were conducted with soils contaminated with heavy metals (Pb and Cr) and aromatic hydrocarbons to determine the effects of each upon microbial community structure and function. Organic substrates were added as a driving force for change in the microbial community. Glucose represented an energy source used by a broad variety of bacteria, whereas fewer soil species were expected to use xylene.