title: Does water chemistry affect the dietary uptake and toxicity of silver nanoparticles by the freshwater snail Lymnaea stagnalis?
abstract: Silver nanoparticles (AgNPs) are widely used in many applications and likely released into the aquatic environment. There is increasing evidence that Ag is efficiently delivered to aquatic organisms from AgNPs after aqueous and dietary exposures. Accumulation of AgNPs through the diet can damage digestion and adversely affect growth. It is well recognized that aspects of water quality, such as hardness, affect the bioavailability and toxicity of waterborne Ag. However, the influence of water chemistry on the bioavailability and toxicity of dietborne AgNPs to aquatic invertebrates is largely unknown. Here we characterize for the first time the effects of water hardness and humic acids on the bioaccumulation and toxicity of AgNPs coated with polyvinyl pyrrolidone (PVP) to the freshwater snail Lymnaea stagnalis after dietary exposures. Our results indicate that bioaccumulation and toxicity of Ag from PVP-AgNPs ingested with food are not affected by water hardness and by humic acids, although both could affect interactions with the biological membrane and trigger nanoparticle transformations. Snails efficiently assimilated Ag from the PVP-AgNPs mixed with diatoms (Ag assimilation efficiencies ranged from 82 to 93%). Rate constants of Ag uptake from food were similar across the entire range of water hardness and humic acid concentrations. These results suggest that correcting regulations for water quality could be irrelevant and ineffective where dietary exposure is important.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain.
authors.forename: Ana López-Serrano
authors.initials: AL
authors.lastname: Oliver
authors.affiliation: U.S. Geological Survey, Menlo Park, CA, USA. Electronic address: mcroteau@usgs.gov.
authors.forename: Marie-Noële
authors.initials: MN
authors.lastname: Croteau
authors.affiliation: John Muir Institute of the Environment, University of California, Davis, CA, USA.
authors.forename: Tasha L
authors.initials: TL
authors.lastname: Stoiber
authors.affiliation: School of Geography, Earth and Environmental Science, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom; School of Public Health, University of Indonesia, Depok, West Java 16424, Indonesia.
authors.forename: Mila
authors.initials: M
authors.lastname: Tejamaya
authors.affiliation: School of Geography, Earth and Environmental Science, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
authors.forename: Isabella
authors.initials: I
authors.lastname: Römer
authors.affiliation: School of Geography, Earth and Environmental Science, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom; Center for Environmental Nanoscience and Risk, University of South Carolina, 29036 SC, USA.
authors.forename: Jamie R
authors.initials: JR
authors.lastname: Lead
authors.affiliation: U.S. Geological Survey, Menlo Park, CA, USA; John Muir Institute of the Environment, University of California, Davis, CA, USA.
authors.forename: Samuel N
authors.initials: SN
authors.lastname: Luoma
mesh_terms: D000818:Animals; D005618:Fresh Water / Q000737:chemistry*; D006812:Humic Substances; D008195:Lymnaea / Q000187:drug effects; D053768:Metal Nanoparticles / Q000032:analysis / Q000633:toxicity*; D012834:Silver / Q000378:metabolism* / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*
chemical_list: D006812:Humic Substances; D014874:Water Pollutants, Chemical; D012834:Silver
keywords: Bioavailability; Dietborne uptake; Freshwater invertebrate; Silver nanoparticles; Water chemistry