Toxicity of Zn-Fe Layered Double Hydroxide to Different Organisms in the Aquatic Environment

Abstract

The application of layered double hydroxide (LDH) nanomaterials as catalysts has attracted great interest due to their unique structural features. It also triggered the need to study their fate and behavior in the aquatic environment. In the present study, Zn-Fe nanolayered double hydroxides (Zn-Fe LDHs) were synthesized using a co-precipitation method and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and nitrogen adsorption-desorption analyses. The toxicity of the home-made Zn-Fe LDHs catalyst was examined by employing a variety of aquatic organisms from different trophic levels, namely the marine photobacterium Vibrio fischeri, the freshwater microalga Pseudokirchneriella subcapitata, the freshwater crustacean Daphnia magna, and the duckweed Spirodela polyrhiza. From the experimental results, it was evident that the acute toxicity of the catalyst depended on the exposure time and type of selected test organism. Zn-Fe LDHs toxicity was also affected by its physical state in suspension, chemical composition, as well as interaction with the bioassay test medium.

Phosphorus Binding by Lanthanum Modified Pyroaurite-like Clay: Performance and Mechanisms

“…The concentrations of La at the end of the experiment were 4.5 μg/L for LMB and 2.6 μg/L for L-CMF-1.0, both meeting the surface water standard for La (10.1 μg/L) in the Netherlands . In addition, the EC 50 values of LDH for various aquatic organisms usually range from 0.10 g/L to 0.81 g/L, all higher than the optimal dosage in this study (0.05 g/L). In fact, the nature of LDHs is clay, which exhibit low to null toxicity to human health and the eco-system and sometimes are used for drug delivery to the human body .…”

Efficient Dye Degradation and Antimicrobial Behavior with Molecular Docking Performance of Silver and Polyvinylpyrrolidone-Doped Zn-Fe Layered Double Hydroxide

“…The average crystallite sizes of pristine and doped nanocomposites examined by the Debye–Scherrer formula were 25, 17.78, 18, 18.32, and 25.5 nm. The interlayer spacing of the (009) reflection plane corresponds to 2.77 Å, which exhibits a greater value than pure nanocomposites as 1.38 Å and depicts an enlargement of lattice spacing that confirms the presence of Ag as a dopant . The interlayer d -spacing d 009 plane examined through Braggs law n λ = 2 d sin θ of PVP/Zn–Fe LDH and 1, 3, and 5% Ag-doped PVP/Zn–Fe LDH is 2.33, 2.69, 2.7, and 2.7 Å, respectively.…”

Peroxydisulfate-assisted sonocatalytic degradation of metribuzin by La-doped ZnFe layered double hydroxide

“…The BET surface area (S BET ), pore volume (V m ), and average pore diameter of the La-doped ZnFe LDH were determined as 110.93 m 2 g −1 , 0.27 cm 3 g −1 , and 9.67 nm, respectively. Previous studies have reported a range of 46.9–108.8 m 2 g −1 for the S BET of ZnFe LDH [33] , [34] , [35] . La doping can enhance the contact areas of LDH by increasing the surface roughness of LDH [27] .…”