title: Differential effect of solar light in increasing the toxicity of silver and titanium dioxide nanoparticles to a fish cell line and zebrafish embryos.
abstract: The increasing use of silver (Ag) and titanium dioxide (TiO2) nanoparticles (NPs) in consumer products and their inevitable seepage into the environment prompted us to investigate their potential toxicity to a fish cell line (BF-2) and zebrafish embryos under dark and Simulated Solar Light (SSL) exposure conditions. Using high throughput screening (HTS) platforms, we showed that the oxidative stress-dependent cytotoxicity and embryonic toxicity of NPs were significantly increased upon exposure to SSL. While, the toxicity of TiO2 NPs under SSL exposure could be explained by hydroxyl radical generation, the enhanced toxicity of Ag NPs under SSL exposure was due to surface oxidation and physicochemical modification of Ag NPs and shedding of Ag+, leading to an increased bioavailability of silver. Our observations that solar light could induce physicochemical transformation of TiO2 and Ag NPs and enhance their toxic potential emphasizes the need for conducting future toxicity studies under environmentally relevant exposure conditions to guide decision making on the safe handling of NPs.
authors.affiliation: Centre for Sustainable Nanotechnology, School of Chemical and Life Sciences, Nanyang Polytechnic , Singapore 569830.
authors.forename: Saji
authors.initials: S
authors.lastname: George
authors.forename: Hannah
authors.initials: H
authors.lastname: Gardner
authors.forename: Eng Khuan
authors.initials: EK
authors.lastname: Seng
authors.forename: Hengky
authors.initials: H
authors.lastname: Chang
authors.forename: Chunyan
authors.initials: C
authors.lastname: Wang
authors.forename: Crystal Hay
authors.initials: CH
authors.lastname: Yu Fang
authors.forename: Mark
authors.initials: M
authors.lastname: Richards
authors.forename: Suresh
authors.initials: S
authors.lastname: Valiyaveettil
authors.forename: Woon Khiong
authors.initials: WK
authors.lastname: Chan
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004625:Embryo, Nonmammalian; D053768:Metal Nanoparticles / Q000528:radiation effects / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects*; D012834:Silver / Q000493:pharmacokinetics / Q000528:radiation effects / Q000633:toxicity*; D013472:Sunlight; D014025:Titanium / Q000493:pharmacokinetics / Q000528:radiation effects / Q000633:toxicity*; D015027:Zebrafish
chemical_list: C009495:titanium dioxide; D012834:Silver; D014025:Titanium