A5066140110- Toxic Organic Pollutants Impact
- Environmental Toxicology and Ecotoxicology
- Pharmaceutical and Antibiotic Environmental Impacts
- Mercury impact and mitigation studies
- Microplastics and Plastic Pollution
- Marine Biology and Ecology Research
- Heavy metals in environment
- Analytical chemistry methods development
- Effects and risks of endocrine disrupting chemicals
- Per- and polyfluoroalkyl substances research
- Marine Biology and Environmental Chemistry
- Pesticide and Herbicide Environmental Studies
- Isotope Analysis in Ecology
- Pesticide Exposure and Toxicity
- Aquatic Ecosystems and Phytoplankton Dynamics
- Radioactive contamination and transfer
- Environmental and Sediment Control
- Environmental Chemistry and Analysis
- Coral and Marine Ecosystems Studies
- Water Quality and Resources Studies
- Aquatic Invertebrate Ecology and Behavior
- Microbial bioremediation and biosurfactants
- Water Treatment and Disinfection
- Water Quality Monitoring and Analysis
- Recycling and Waste Management Techniques
U.S. Army Engineer Research and Development Center
2015-2025
United States Army
2013-2025
United States Army Corps of Engineers
2002-2021
Cold Regions Research and Engineering Laboratory
2021
Oak Ridge Associated Universities
2021
Oak Ridge Institute for Science and Education
2021
Naval Information Warfare Center Pacific
2011-2017
Thomas Jefferson National Accelerator Facility
2017
Walker (United States)
2017
United States Geological Survey
2014
An approach for comparing laboratory and field measures of bioaccumulation is presented to facilitate the interpretation different sources data. Differences in numerical scales units are eliminated by converting data dimensionless fugacity (or concentration-normalized) ratios. The expresses metrics terms equilibrium status chemical, with respect a reference phase. When ratios plotted, degree variability within across easily visualized given chemical because their same all endpoints. Fugacity...
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...
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...
Researchers have developed numerous per- and polyfluoroalkyl substances (PFAS)-free aqueous film-forming foam (AFFF) formulations to replace PFAS-containing AFFF used for fire suppression. As part of the Department Defense's Strategic Environmental Research Development Program (SERDP), we examined direct lethal effects seven PFAS-free a on 14 aquatic species using series concentration (LC50) tests. We assessed LC10, LC50, LC90 values log–logistic logit analyses. Across all tested, discovered...
Abstract The toxicity and toxicokinetics of radiolabeled DDT its major degradation products, dichlorodiphenyldichloroethane (DDD) dichlorodiphenyldichloroethylene (DDE), were determined for the amphipods Hyalella azteca Diporeia spp. in water-only static renewal exposures. Comparison water tissue concentrations associated with decreased survival revealed large differences among three compounds. In H. azteca, ratio 10-d LR50 values (median lethal residue) DDT:DDD:DDE was 1:24:195. spp., 28-d...
Abstract An initiative within the US military is targeting replacement of traditional munitions constituents with insensitive to reduce risk accidental detonation. The purpose present study was comparatively assess toxicity 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) new 2,4-dinitroanisole (DNAN) 3-nitro-1,2,4-triazol-5-one (NTO). following exposure durations were performed Rana pipiens (leopard frog) tadpoles: TNT DNAN, 96 h 28 d; RDX, 10 d NTO, d. 96-h 50%...
Mercury-specific diffusive gradient in thin films (DGTs) were used laboratory microcosms as a biomonitoring tool to assess the lability of mercury (Hg) total and monomethylmercury Hg (MeHg), develop relationship between chemical bioavailability estuarine sediments. Time-series deployment DGTs sediments showed that sediment-bound MeHg is more labile than inorganic Hg. In subsequent experiments, deployed simultaneously with three benthic macroinvertebrates (the amphipod, Leptocheirus...
The present study evaluated polar organic chemical integrative samplers (POCIS) for quantification of conventional munitions constituents, including trinitrotoluene (TNT), aminodinitrotoluenes, diaminonitrotoluenes, dinitrotoluene, and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in a field setting. POCIS were deployed at varying distances from the commonly used explosive formulation composition B (39.5% TNT, 59.5% RDX, 1% wax) an embayment Santa Rosa Sound (Pensacola, FL, USA)....
To enable risk characterization of perfluorooctane sulfonic acid (PFOS) in extended chronic and multi-generational exposures, we assessed PFOS bioconcentration zebrafish (Danio rerio) exposed continuously to environmentally-relevant concentrations (0, 0.1, 0.6, 3.2, 20, 100 µg/L PFOS) through 180 days postfertilization (dpf) parental (P) first filial generation (F1) fish. Exposures included five replicate tanks per treatment where whole-body were measured using 20-35 fish at 14 29 dpf the P...
We investigated the accumulation of per- and polyfluoroalkyl substances (PFAS) in earthworms (Eisenia andrei). Uptake kinetics bioaccumulation factors (BAFs) were determined using a mixture 16 PFAS by exposing to spiked artificial soil for up 28 d. Two treatments used, with low treatment targeting environmentally relevant concentrations. The concentrations remained relatively unchanged during exposures statistically significant rates uptake estimated most individual PFAS. For 0.01 mg/kg...
We explored a novel technique to deploy solid-phase microextraction (SPME) fibers nondestructively measure the explosive compound 2,4,6-trinitrotoluene (TNT) and its nitroaromatic (NA) degradation products in laboratory sediment toxicity tests field sediments situ. SPME within steel mesh envelopes were exposed statically via direct burial sediment. Six fiber types (polymer coatings) tested. Polyacrylate (PA) was sufficiently durable for this application, yielded lowest detection limits,...
Corals represent symbiotic meta-organisms that require harmonization among the coral animal, photosynthetic zooxanthellae and associated microbes to survive environmental stresses. We investigated integrated-responses in scleractinian Acropora formosa response an emerging marine pollutant, munitions constituent, 1,3,5-trinitro-1,3,5 triazine (RDX; 5 day exposures 0 (control), 0.5, 0.9, 1.8, 3.7, 7.2 mg/L, measured seawater). RDX accumulated readily soft tissues with bioconcentration factors...
Abstract Previous investigations of the ecotoxicity TNT in spiked sediments noted rapid degradation and disappearance toxicant, yet little is understood regarding effects this process on toxicity subsequent derivation reference values. We conducted environmental fate studies 28‐d sediment tests with benthic oligochaete worms ( Tubifex tubifex ) at three different concentrations (440, 1,409, 4,403 nmol/g dry wt) aged for 1, 8, 29 d. Because TNT, products, partitioning to overlying water, only...