No abstract

By taking a life cycle approach to study the potential for silver nanoparticle (AgNP) release from functionalized textiles, we can estimate the relative importance of different phases to the release of Ag over time.

Increasing use of silver nanoparticles (AgNPs) in consumer products has raised concerns about the potential impacts of AgNPs on the environment. This study aimed to assess the potential release of AgNPs from textiles due to sequential washing. Different types of fabrics including cotton, polyester (PES), and cotton blended with PES (called TC) were coated with 4-5 nm AgNPs and used in the sequential washing experiments with Milli-Q water at neutral pH and with commercial detergent at alkaline pH. Similar experiments were also run-on consumer textile products washed with Milli-Q water. The percent Ag remaining on the products after washing was also investigated. The initial Ag contents ranged from 254 to 350 μg Ag/g of the product in lab-prepared fabrics and from 1.2 to 44 μg Ag/g of the product in consumer products. After 20 wash cycles, 48 to 72 % of Ag was lost from the prepared fabrics washed with Milli-Q water, while a greater loss of 84-94 % of Ag occurred after washing the prepared fabrics with commercial detergent. The Ag released during the washing process is present dominantly in particulate form. In the consumer products after 20 washes with Milli-Q water, the percent Ag remaining was found to be around 46 to 70 %. Statistical analysis of the Ag release rate between consumer products and lab-prepared fabrics in Milli-Q washing water by independent t test showed no significant difference after 20 washing cycles (p > 0.05).

The use of nanosilver as an antibacterial agent for various products has increased, especially so, in textiles. This study aims to investigate the potential of Ag to leach from commercial products which contain nano-Ag by using the toxicity characteristic leaching procedure (TCLP) test in accordance with USEPA method 1311. Eight nano-Ag products were purchased from the market. Only those products that are likely to be disposed of in a landfill after end use were selected. Nano-Ag fabrics of different concentrations were also prepared at the laboratory scale, and the TCLP test was performed on them as well. The current study assumes that the new products were discarded without use. The Ag content was quantified by inductively coupled plasma-mass spectroscopy (ICP-MS) and ranged from 0.95 to 2.82 μg/g of the product in the commercial products and from 1.49 to 350 μg/g of the product in the lab-prepared fabrics. In the TCLP test results, Ag concentrations ranged from 4.3 to 64.9 μg/L in the commercial products and from 28.9 to 28,381 μg/L in the lab-prepared fabrics. The results also indicate that the amount of Ag released depends on the type of the fabrics. Additionally, the size of the nano-Ag released in percentage is different for each prepared fabric. This study can help in understanding the amount of Ag released during the disposal phase of a product in a landfill.