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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).
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RESEARCH ARTICLE
Release of silver nanoparticles from fabrics
during the course of sequential washing
Pawena Limpiteeprakan
1
&Sandhya Babel
1
&Jenyuk Lohwacharin
2
&Satoshi Takizawa
2
Received: 11 April 2016 / Accepted: 16 August 2016 /Published online: 26 August 2016
#Springer-Verlag Berlin Heidelberg 2016
Abstract 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 cot-
ton, polyester (PES), and cotton blended with PES (called TC)
were coated with 45 nm AgNPs and used in the sequential
washing experiments with Milli-Q water at neutral pH and
with commercial detergent at alkaline pH. Similar experi-
ments 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 8494 % of Ag occurred after washing
the prepared fabrics with commercial detergent. The Ag re-
leased 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 ttest showed no significant
difference after 20 washing cycles (p>0.05).
Keywords Consumer products .ICP-MS .Nanotechnology .
Silver nanoparticles .Textile s .Wa shing test
Introduction
Silver nanoparticles (AgNPs) are applied on textiles to avoid
infections that can be caused by pathogenic microorganisms
andtoeliminatethegrowthofodor-causingbacteria
(Gorensek and Recelj 2007). However, the impact of using
AgNPs in consumer products and the potential impacts of Ag
ions released during long-term usage is still not clear
(Schluesener and Schluesener 2013). AgNPs may be
discharged into the aquatic environment during their life cy-
cle, including the synthesis, manufacturing, use, and disposal
phases (Köhler et al. 2008). For instance, during the use phase,
the released AgNPs may enter wastewater treatment plants
through spent washing water (Benn et al. 2010; Farkas et al.
2011) because AgNPs are washed out from Ag containing
clothes during washing cycles (Griffitt et al. 2008;Geranio
et al. 2009; Windler et al. 2013; Mitrano et al. 2014). The
estimated releases of AgNPs in 2012 from wastewater treat-
ment plants into surface water were reported to be 1.76
tons/year in the EU region (Sun et al. 2014). The analysis of
substance flow from products to water by Mueller and
Nowack (2008) showed that the release of nanoparticles re-
sulted in an AgNP concentration of 0.03 μg/L in natural wa-
ters. AgNPs release Ag ions that are toxic even at low con-
centrations (0.1 to 5 μg/L) to many living organisms including
Responsible editor: Thomas D. Bucheli
Electronic supplementary material The online version of this article
(doi:10.1007/s11356-016-7486-3) contains supplementary material,
which is available to authorized users.
*Sandhya Babel
sandhya@siit.tu.ac.th
1
School of Biochemical Engineering and Technology, Sirindhorn
International Institute of Technology, Thammasat University, Pathum
Thani 12121, Thailand
2
Department of Urban Engineering, University of Tokyo,
Tokyo 113-8656, Japan
Environ Sci Pollut Res (2016) 23:2281022818
DOI 10.1007/s11356-016-7486-3
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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