Bioaccumulation but no biomagnification of silver sulfide nanoparticles in freshwater snails and planarians

Metal transfer to sediments, invertebrates and fish following waterborne exposure to silver nitrate or silver sulfide nanoparticles in an indoor stream mesocosm

“…While the Ag 2 S form is less toxic than pristine Ag NPs (e.g., to Chironomus riparius (Lee et al, 2016); adult zebra fish, Danio rerio (Devi et al, 2015)), it is not clear if the bioaccumulation hazard remains for Ag 2 S NPs. In at least one study with rainbow trout, Ag 2 S NPs were much less bioavailable than either the metal salt or Ag NPs (Clark et al, 2019a), with similar observations made in snails and planarians (Silva et al, 2022). However, in fish at least, nanoparticles arising from the Ag 2 S NP exposure were also detected in the internal organs (Clark et al, 2021), indicating that some bioaccumulation of particulates occurred.…”

“…The planarians and the chironomid larvae (Table 1) showed much higher Ag concentrations than the oligochaete worms, with a clearer time-dependent Ag accumulation from both the AgNO 3 and Ag 2 S NPs treatment, respectively. There are only a few reports on the bioaccumulation of metals in planarians, and only one recent study on Ag from the same laboratory that conducted the mesocosm experiment reported here (Silva et al, 2022). Nonetheless, for Cd, the planarian, Dugesia japonica showed metal accumulation with the induction of metallothionein inferring metal chelation inside the tissue (Wu et al, 2011).…”

“…In our previous work, Ag 2 S NPs, as the most relevant environmental transformation (form) of Ag NPs, was explored for its bioaccumulation potential in single species studies on: dicotyledonous crop, Khodaparast et al (2022); wheat crop, Lahive et al (2021); earthworms, Baccaro et al (2019); meal worms, Khodaparast et al (2021); planarians, Silva et al (2022); aquatic snails, Silva et al (2020) and trout, Clark et al (2019a).…”

Emerging investigator series: metal nanoparticles in freshwater: transformation, bioavailability and effects on invertebrates

“… 125 Recent work highlights the higher Ag bioaccumulation potential in the Ag + treatment compared with Ag 2 SNP exposures, but no biomagnification was observed from the freshwater snail Physa acuta to the planarian Girardia tigrina . 129 To fully mimic the real environmental scenario with a food chain with more than three species, another study constructed a freshwater ecosystem (including clam C. fluminea , snail P. acuta , and water flea D. magna ) and determined the bioaccumulation and biomagnification of CeO 2 NPs via long-term exposure. Results found that bioaccumulated Ce in all tested species was negatively correlated with its trophic level, showing no biomagnification of CeO 2 NPs through this food web.…”

Comparative study of the sensitivity of two freshwater gastropods, Lymnaea stagnalis and Planorbarius corneus, to silver nanoparticles: bioaccumulation and toxicity

“…Two types of endpoints were assessed in the gastropods following exposure to AgNPs: 1) bioaccumulation and 2) biological responses. The exposure time (7d) was chosen because this time had previously been shown to allow for Ag accumulation (Croteau et al, 2011b;Silva et al, 2022) and could trigger biological responses of freshwater gastropods to metal NPs (Ma et al, 2017). Gastropods were not fed during the whole exposure to minimize faecal scavenging.…”