Hazard assessment of a silver nanoparticle in soil applied via sewage sludge

Abstract

Background: Silver nanoparticles (AgNPs) are widely used in many fields of application and consumer products due to their antibacterial properties. The aim of this study was to prepare a hazard assessment for one specific AgNP in soil, incorporated via sewage sludge (the sewage sludge pathway). The effects of pristine AgNPs on microorganisms, plants and earthworms were first determined in screening tests. Long-term tests over 140 days were then conducted with AgNPs added to soil via sewage sludge. AgNPs were incorporated into the sludge through a simulated sewage treatment plant (STP) over 10 days to allow transformation to occur and also by manual spiking over 2 h. The results of the most sensitive organism from the long-term tests, the soil microorganisms, are presented.

Collembola Reproduction Decreases with Aging of Silver Nanoparticles in a Sewage Sludge-Treated Soil

“…Several studies (e.g., Hänsch and Emmerling, 2010;Feng et al, 2013;Schlich et al, 2013b; have shown that AgNP at environmentally relevant concentrations below 1 mg Ag kg −1 cause adverse effects to soil organisms of various trophic levels (McKee and Filser, 2016). Predicted environmental concentrations of AgNP in soil and sludgeamended soil differ between studies, but all lay in the ng to µg Ag kg −1 soil range.…”

“…The focus in ecotoxicological testing of AgNP in soil has, thus far, been more on microorganisms (Schlich et al, 2013b;Engelke et al, 2014;McKee and Filser, 2016), earthworms (Heckmann et al, 2011;Shoults-Wilson et al, 2011a;Schlich et al, 2013a;van der Ploeg et al, 2014;Novo et al, 2015), enchytraeids (Gomes et al, 2013(Gomes et al, , 2015Ribeiro et al, 2015;Bicho et al, 2016) and nematodes (Roh et al, 2009;Meyer et al, 2010). Collembola have received less attention.…”

“…During production, use and disposal AgNP can be emitted and enter the environment via several pathways; soils are considered a major sink of NP (Keller and Lazareva, 2014). AgNP accumulate in sewage sludge of waste water treatment plants (WWTP) which is applied to agricultural soils as fertilizer (Tourinho et al, 2012;Batley et al, 2013;Schlich et al, 2013b). Some plant protection products and fertilizers also include AgNP and enter terrestrial ecosystems via application to crops (Mishra and Singh, 2015).…”

“…During the WWTP processing transformations and modifications of the pristine AgNP take place (Kim et al, 2010). Hence, WWTP simulations allow the nanoparticles and ions to be exposed to possible transformation reactions, thus providing maximum environmental relevance (Schlich et al, 2013b).…”

Nanopharmaceuticals: Tiny challenges for the environmental risk assessment of pharmaceuticals

“…It cannot presently be concluded whether the total residue approach, which covers metabolites and the transformation products of a human medicinal product and considers the ecotoxicity of the parent compound, is applicable for nanopharmaceuticals. Aging, alteration, or transformation of the nanomaterials are recognized as important processes influencing the ecotoxicological effects observed [52][53][54][55].…”