Back to Search
Start Over
Transformation of AgCl nanoparticles in a sewer system--A field study
- Source :
- The Science of the total environment. 535
- Publication Year :
- 2014
-
Abstract
- Silver nanoparticles (Ag-NP) are increasingly used in consumer products and their release during the use phase may negatively affect aquatic ecosystems. Research efforts, so far, have mainly addressed the application and use of metallic Ag(0)-NP. However, as shown by recent studies on the release of Ag from textiles, other forms of Ag, especially silver chloride (AgCl), are released in much larger quantities than metallic Ag(0). In this field study, we report the release of AgCl-NP from a point source (industrial laundry that applied AgCl-NP during a piloting phase over a period of several months to protect textiles from bacterial regrowth) to the public sewer system and investigate the transformation of Ag during its transport in the sewer system and in the municipal wastewater treatment plant (WWTP). During the study period, the laundry discharged ~85 g of Ag per day, which dominated the Ag loads in the sewer system from the respective catchment (72-95%) and the Ag in the digested WWTP sludge (67%). Combined results from electron microscopy and X-ray absorption spectroscopy revealed that the Ag discharged from the laundry to the sewer consisted of about one third AgCl and two thirds Ag2S, both forms primarily occurring as nanoparticles with diameters100 nm. During the 800 m transport in the sewer channel to the nearby WWTP, corresponding to a travel time of ~30 min, the remaining AgCl was transformed into nanoparticulate Ag2S. Ag2S-NP also dominated the Ag speciation in the digested sludge. In line with results from earlier studies, the very low Ag concentrations measured in the effluent of the WWTP (0.5 μg L(-1)) confirmed the very high removal efficiency of Ag from the wastewater stream (95%).
- Subjects :
- Environmental Engineering
Sewage
Chemistry
Laundry
Silver sulfide
Environmental engineering
Nanoparticle
Silver Compounds
Wastewater
Pollution
Silver nanoparticle
Metal
Silver chloride
chemistry.chemical_compound
Models, Chemical
visual_art
Environmental chemistry
visual_art.visual_art_medium
Environmental Chemistry
Nanoparticles
Waste Management and Disposal
Effluent
Water Pollutants, Chemical
Environmental Monitoring
Subjects
Details
- ISSN :
- 18791026
- Volume :
- 535
- Database :
- OpenAIRE
- Journal :
- The Science of the total environment
- Accession number :
- edsair.doi.dedup.....03521fdfa50de2f7feed09dc7188bf8c