Silver nanoparticles (AgNP) are one type of contaminant that can enter treatment wetlands (Wiesner 2006) and impact the overall treatment efficacy. Grazing by filter feeding zooplankton, such as Daphnia magna, is critical to treatment wetland functioning (Ismail 2019), but the effects of AgNP on zooplankton are not fully understood, especially at environmentally relevant concentrations. In this study, the bioaccumulation kinetics of dissolved and nanoparticulate Ag in D. magna exposed to environmentally relevant Ag concentrations were characterized using isotopically labelled Ag as a tracer. References: Wiesner MR, Lowry GV, Alvarez P, Dionysiou D, Biswas P. 2006. Assessing the Risks of Manufactured Nanomaterials. Environmental Science & Technology 40:4336-4345. Ismail NS, Blokker BM, Feeney TR, Kohn RH, Liu J, Nelson VE, Ollive MC, Price SBL, Underdah EJ. 2019. Impact of Metazooplankton Filter Feeding on Escherichia coli under Variable Environmental Conditions. Applied and Environmental Microbiology 85: e02006-02019.

Ionic silver (Ag+) is being investigated as a residual biocide for use in NASA spacecraft potable water systems on future crewed missions. This water will be used to irrigate future spaceflight crop production systems. We have evaluated the impact of three concentrations (31 ppb, 125 ppb, and 500 ppb) of ionic silver biocide solutions on lettuce in an arcillite (calcinated clay particle substrate) and hydroponic (substrate-less) growth setup after 28 days. Lettuce plant growth was reduced in the hydroponic samples treated with 31 ppb silver and severely stunted for samples treated at 125 ppb and 500 ppb silver. No growth defects were observed in arcillite-grown lettuce. Silver was detectable in the hydroponic-grown lettuce leaves at each concentration but was not detected in the arcillite-grown lettuce leaves. Specifically, when 125 ppb silver water was applied to a hydroponics tray, Ag+ was detected at an average amount of 7 ug/g (dry weight) in lettuce leaves. The increase in Ag+ corresponded with a decrease in several essential elements in the lettuce tissue (Ca, K, P, S). In the arcillite growth setup, silver did not impact the plant root zone microbiome in terms of alpha diversity and relative abundance between treatments and control. However, with increasing silver concentration, the alpha diversity increased in lettuce root samples and in the water from the hydroponics tray samples. The genera in the hydroponic root and water samples were similar across the silver concentrations but displayed different relative abundances. This suggests that ionic silver was acting as a selective pressure for the microbes that colonize the hydroponic water. The surviving microbes likely utilized exudates from the stunted plant roots as a carbon source. Analysis of the root-associated microbiomes in response to silver showed enrichment of metagenomic pathways associated with alternate carbon source utilization, fatty-acid synthesis, and the ppGpp (guanosine 3'-diphosphate 5'-diphosphate) stringent response global regulatory system that operates under conditions of environmental stress. Nutrient solutions containing Ag+ in concentrations greater than 31 ppb in hydroponic systems lacking cation-exchange capacity can severely impact crop production due to stunting of plant growth.

We propose to develop a new highly sensitive instrument to confirm the existence of the so-called nano-dust particles, characterize their impact parameters, and measure their chemical composition. Simultaneous theoretical studies will be used to derive the expected  mass and velocity ranges of these putative particles to formulate science and measurement requirements for the future deployment of  the proposed Nano-Dust Analyzer (NDA) 

Early dust instruments onboard Pioneer 8 and 9 and Helios spacecraft detected a flow of submicron sized dust particles coming from the direction of the Sun. These particles originate in the inner solar system from mutual collisions among meteoroids and move on  hyperbolic orbits that leave the Solar System under the prevailing radiation pressure force. Later dust instruments with higher  sensitivity had to avoid looking toward the Sun because of interference from the solar wind and UV radiation and thus contributed  little to the characterization of the dust stream. The one exception is the Ulysses dust detector that observed escaping dust particles  high above the solar poles, which confirm the suspicion that charged nanometer sized dust grains are carried to high heliographic  latitudes by electromagnetic interactions with the Interplanetary Magnetic Field (IMF). Recently, the STEREO WAVES instruments  recorded a large number of intense electric field signals, which were interpreted as impacts from nanometer sized particles striking the  spacecraft with velocities of about the solar wind speed. This high flux and strong spatial and/or temporal variations of nanometer  sized dust grains at low latitude appears to be uncorrelated with the solar wind properties. This is a mystery as it would require that  the total collisional meteoroid debris inside 1 AU is cast in nanometer sized fragments. The observed fluxes of inner-source pickup ions  also point to the existence of a much enhanced dust population in the nanometer size range. 

This new heliospherical phenomenon of nano-dust streams may have consequences throughout the planetary system, but as of yet no dust instrument exists that could be used to shed light on their properties.  We propose to develop a dust analyzer capable to detect and  analyze these mysterious dust particles coming from the solar direction and to embark upon complementary theoretical studies to  understand their characteristics. The instrument is based on the Cassini Dust Analyzer (CDA) that has analyzed the composition of  nanometer sized dust particles emanating from the Jovian and Saturnian systems but could not be pointed towards the Sun. By  applying technologies implemented in solar wind instruments and coronagraphs a highly sensitive dust analyzer will be developed and  tested in the laboratory. The dust analyzer shall be able to characterize impact properties (impact charge and energy distribution of  ions from which mass and speed of the impacting grains may be derived) and chemical composition of individual nanometer sized  particles while exposed to solar wind and UV radiation. The measurements will enable us to identify the source of the dust by  comparing their elemental composition with that of larger micrometeoroid particles of cometary and asteroid origin and will reveal  interaction of nano-dust with the interplanetary medium by investigating the relation of the dust flux with solar wind and IMF  properties. 

Complementary theoretically studies will be performed to understand the characteristics of nano-dust particles at 1 AU to answer the  following questions:  - What is the speed range at which nanometer sized particles impact

Data base includes SEM and digital photo images of aged nanomaterials, FTIR and UV-Vis spectroscopy data, contact angle of water on aged surfaces. This dataset is associated with the following publication: Zepp, R., E. Ruggiero, B. Acrey, M.J.B. Davis, C. Han, H. Hsieh, K. Vilsmeier, W. Wohlleben, and E. Sahle-Demessie. Fragmentation of polymer nanocomposites: modulation by dry and wet weathering, fractionation, and nanomaterial filler. Environmental Science: Nano. RSC Publishing, Cambridge, UK, 7: 1742-1758, (2020).

Data collected in a series of laboratory experiments conducted with the model freshwater snail Lymnaea stagnalis exposed to dissolved platinum (Pt), or polyvinylpyrrolidone coated platinum nanoparticles (PtNPs) of five different nominal hydrodynamic diameters in the presence (or absence) of natural organic matter (NOM) are presented in this data release. Files include 1) a data dictionary describing the variables; 2) exposure characteristics of the experimental solutions; 3) Pt concentrations in the experimental organisms; and 4) QA/QC performed during the analysis. Format of the files is comma delimited (*.csv).

The data set describes the characterization of organosilica nanoparticle thin films used to adsorb PCBs from laboratory water and a sediment collected near Anniston Alabama. Data not shown here for the porewater and sediment PCB concentrations can be found in Appendix 1 of Ingersoll et al. 2014 (http://dx.doi.org/10.3133/sir20135125) Bulk sediment chemistry was obtained from Table A1-3a.Porewater estimated from solid phase microextraction fibers was obtained from Table A1-3c. The concentration of PCB in Lumbriculus variegatus was obtained from Table A1-3e.

Degradation kinetics of nanocomposite in the environment. Nano-polymer composites are exposed to sunlight and oxidizing conditions that cause weathering of the polymers, leading to degradation and the release of nanoparticles. This dataset is associated with the following publication: Han, C., E. Sahle-Demessie, A. Zhao, T. Richardson, and J. Wang. Environmental aging and degradation of multiwalled carbon nanotube reinforced polypropylene. CARBON. Pergamon Press Ltd., New York, NY, USA, 129: 137-151, (2018).

This data package was created 2025-12-03 08:20:34 by NPSTORET and includes selected project, location, and result data. Data are from Ernest A. Matson's (University of Guam's Marine Laboratory) 1990 Technical Report (#93) entitled "Effects of the Agat, Agana, and Northern District Wastewater Effluents on Receiving Water Quality (Chemistry and Bacteriology) and the Effects of the Agat Effluent on Success of Sea Urchin Egg Fertilization". Data contained in WAPA_NPSTORET_BE.ACCDB (NPSTORET back-end file) were filtered to include: Organization: - WAPA: War in the Pacific National Historical Park Project: - WAPA0009: Effects of the Agat and Agana Wastewater Effluents on Receiving Water Quality Station: - Include Trip QC And All Station Visit Results Value Status: - Accepted or Certified (exported as Final) or Final The data package is organized into five data tables: - Projects.csv - describes the purpose and background of the monitoring efforts - Locations.csv - documents the attributes of the monitoring locations/stations - Results.csv - contains the field measurements, observations, and/or lab analyses for each sample/event/data grouping - HUC.csv - enumerates the domain of allowed values for 8-digit and 12-digit hydrologic unit codes utilized by the Locations data table - Characteristics.csv - enumerates the domain of characteristics available in NPSTORET to identify what was sampled, measured or observed in Results Period of record for filtered data is 1989-02-09 to 1989-12-12. This data package is a snapshot in time of one National Park Service project. The most current data for this project, which may be more or less extensive than that in this data package, can be found on the Water Quality Portal at: https://www.waterqualitydata.us/data/Result/search?project=WAPA0009&mimeType=csv&zip=yes&dataProfile=biological&providers=STORET

This data package was created 2025-12-03 08:20:34 by NPSTORET and includes selected project, location, and result data. Data are from Ernest A. Matson's (University of Guam's Marine Laboratory) 1990 Technical Report (#93) entitled "Effects of the Agat, Agana, and Northern District Wastewater Effluents on Receiving Water Quality (Chemistry and Bacteriology) and the Effects of the Agat Effluent on Success of Sea Urchin Egg Fertilization". Data contained in WAPA_NPSTORET_BE.ACCDB (NPSTORET back-end file) were filtered to include: Organization: - WAPA: War in the Pacific National Historical Park Project: - WAPA0009: Effects of the Agat and Agana Wastewater Effluents on Receiving Water Quality Station: - Include Trip QC And All Station Visit Results Value Status: - Accepted or Certified (exported as Final) or Final The data package is organized into five data tables: - Projects.csv - describes the purpose and background of the monitoring efforts - Locations.csv - documents the attributes of the monitoring locations/stations - Results.csv - contains the field measurements, observations, and/or lab analyses for each sample/event/data grouping - HUC.csv - enumerates the domain of allowed values for 8-digit and 12-digit hydrologic unit codes utilized by the Locations data table - Characteristics.csv - enumerates the domain of characteristics available in NPSTORET to identify what was sampled, measured or observed in Results Period of record for filtered data is 1989-02-09 to 1989-12-12. This data package is a snapshot in time of one National Park Service project. The most current data for this project, which may be more or less extensive than that in this data package, can be found on the Water Quality Portal at: https://www.waterqualitydata.us/data/Result/search?project=WAPA0009&mimeType=csv&zip=yes&dataProfile=biological&providers=STORET