A5010253865- Environmental Toxicology and Ecotoxicology
- Nanoparticles: synthesis and applications
- Toxic Organic Pollutants Impact
- Aquatic Invertebrate Ecology and Behavior
- Pharmaceutical and Antibiotic Environmental Impacts
- Heavy metals in environment
- Mercury impact and mitigation studies
- Pesticide and Herbicide Environmental Studies
- Electrochemical Analysis and Applications
- Water Quality and Resources Studies
- Microplastics and Plastic Pollution
- Aquatic Ecosystems and Phytoplankton Dynamics
- Fish Ecology and Management Studies
- Coal and Its By-products
- Water Quality and Pollution Assessment
- Marine and coastal ecosystems
- Pesticide Exposure and Toxicity
- Analytical chemistry methods development
- Per- and polyfluoroalkyl substances research
- Healthcare and Environmental Waste Management
- Risk and Safety Analysis
- Orthopaedic implants and arthroplasty
- Graphene and Nanomaterials Applications
- Marine Biology and Environmental Chemistry
- Nanotechnology research and applications
United States Geological Survey
2014-2025
Columbia Environmental Research Center
2017-2024
University of Illinois Urbana-Champaign
2020
U.S. Army Engineer Research and Development Center
2008-2018
University of Mississippi
1997-2017
United States Army
2006-2015
United States Army Corps of Engineers
2002-2014
Virginia Tech
2009-2010
Luna Innovations (United States)
2009-2010
Arkansas State University
2010
For decades, we have known that chemicals affect human and wildlife behavior. Moreover, due to recent technological computational advances, scientists are now increasingly aware a wide variety of contaminants other environmental stressors adversely organismal behavior subsequent ecological outcomes in terrestrial aquatic ecosystems. There is also groundswell concern regulatory ecotoxicology does not adequately consider behavior, primarily lack standardized toxicity methods. This has, turn,...
Carbon nanotubes (NTs) may be among the most useful engineered nanomaterials for structural applications but could difficult to study in ecotoxicological evaluations using existing tools relative with a lower aspect ratio. Whereas hydrophobicity and van der Waals interactions of NTs suggest aggregation sedimentation aquatic systems, consideration regarding how surface modifications influence their environmental fate toxicology is needed. Surface (e.g., functional groups coatings) are...
This investigation applied novel techniques for characterizing and fractionating nanosilver particles aggregates relating these measurements to toxicological endpoints. The acute toxicity of eight suspensions varying primary particle sizes (10-80 nm) coatings (citrate, polyvinylpyrrolidone, EDTA, proprietary) was assessed using three aquatic test organisms (Daphnia magna, Pimephales promelas, Pseudokirchneriella subcapitata). When 48-h lethal median concentrations (LC50) were expressed as...
The potential exists for laboratory personnel to be exposed engineered carbon-based nanomaterials (CNMs) in studies aimed at producing conditions similar those found natural surface waters [e.g., presence of organic matter (NOM)].The goal this preliminary investigation was assess the release CNMs into atmosphere during handling and sonication environmentally relevant matrices.We measured fullerenes (C60), underivatized multiwalled carbon nanotubes (raw MWCNT), hydroxylated MWCNT (MWCNT-OH),...
Few studies have considered the environmental impacts of impurities and byproducts associated with low-efficiency nanomanufacturing processes. Here, we study composition aquatic toxicity low-purity, as-produced fullerenes (C60) metallofullerene waste solids, both which were generated via arc-discharge synthesis. Scanning electron microscopy energy dispersive X-ray spectroscopy (SEM-EDX) inductively coupled plasma mass (ICP-MS) used to characterize metals solid test materials aqueous...
Abstract Nano‐sized aluminum is currently being used by the military and commercial industries in many applications including coatings, thermites, propellants. Due to potential for wide dispersal soil systems, we chose investigate fate effects of nano‐sized oxide (Al 2 O 3 ), oxidized form nano aluminum, a terrestrial organism. The toxicity bioaccumulation micron‐sized (50–200 µm, nominal) (11 nm, Al was comparatively assessed through acute subchronic bioassays using earthworm, Eisenia...
Studies investigating the impact of particle size and capping agents on nanosilver toxicity in pristine laboratory conditions are becoming available. However, relative importance known environmental mitigating factors for dissolved silver remains poorly characterized context with existing predictive models. This study investigated implications freshly prepared versus stored 20 100 nm stocks to freshwater zooplankton (Ceriodaphnia dubia) presence absence organic carbon (DOC). Results...
Nanoparticles are of concern because widespread use, but it is unclear if metal nanoparticles cause effects directly or indirectly. We explored whether polyvinylpyrrolidone-coated silver (PVP-AgNPs) through intact dissolved silver. Females the model species fathead minnow (Pimephales promelas) were exposed to either 4.8 μg/L AgNO3 61.4 PVP-AgNPs for 96h. Microarray analyses used identify impacted receptors and toxicity pathways in liver brain tissues that confirmed using vitro mammalian...
Nanomaterials and their associated technologies hold promising opportunities for the development of new materials applications in a wide variety disciplines, including medicine, environmental remediation, waste treatment, energy conservation. However, current information regarding effects health risks with nanomaterials is limited sometimes contradictory. This article summarizes conclusions 2008 NATO workshop designed to evaluate wide-scale implications (e.g., benefits, risks, costs) use on...
Knowledge gaps in nanomaterial fate and toxicity currently limit the ability of risk assessments to characterize environmental implications nanomaterials. This problem is further complicated by lack standardized characterization preparation methodologies for researchers gain needed information assist assessors. In present study, data were generated determine if multiwalled nanotube (MWNT) are altered engineered surface modifications or different dispersal methods. While dissolved organic...
As the production and applications of silver nanoparticles (AgNPs) increase, it is essential to characterize fate effects in environmental systems. Nanosilver materials may settle from suspension; therefore, authors' objective was utilize environmentally relevant bioassays study impact, bioaccumulation, tissue distribution, uptake, depuration AgNPs on a sediment-dwelling invertebrate, Lumbriculus variegatus. Hydrodynamic diameters uncoated 30-nm, 80-nm, 1500-nm AgNP powders polyvinyl...
Aqueous film-forming foams historically were used during fire training activities on Joint Base Cape Cod, Massachusetts, and created an extensive per- polyfluoroalkyl substances (PFAS) groundwater contamination plume. The potential for PFAS bioconcentration from exposure to the contaminated groundwater, which discharges surface water bodies, was assessed with mobile-laboratory experiments using plume a nearby reference location. on-site continuous-flow 21-day exposures male female fathead...
The toxicity of the explosives 2,4,6-trinitrotoluene (TNT); hexahydro-1,3,5-trinitro-1,3,5-triazine (royal demolition explosive [RDX]); and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (high-melting [HMX]), was evaluated in spiked sediment with two freshwater invertebrates. midge Chironomus tentans amphipod Hyalella azteca demonstrated significant toxic effects after exposure to TNT its degradation products, 1,3,5-trinitrobenzene (TNB) 2,4-diamino-6-nitrotoluene (2,4-DANT). Significant...