The increasing use of platinum in different forms including engineered nanoparticles (PtNPs) in a wide range of industrial applications and in particular in automotive catalysts is leading to a rising concern about their release and fate in the environment. This study investigates for the first time the uptake and fate of PtNPs by plants. Two model organisms Lepidium sativum and Sinapis alba were exposed to 70 nm PtNPs. An enzymatic digestion method was developed in order to extract intact PtNPs from the different plant tissues, optimizing different parameters in order to obtain the highest number of nanoparticles. Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) was developed to provide information about nanoparticle size, nanoparticle number concentration and the presence of dissolved platinum in the samples. The enzymatic treatment allowed the extraction of PtNPs from the different tissues without changing their oxidation or aggregation state. The presence of PtNPs at the nominal size in all tissues from both plants was observed. PtNPs with higher sizes than the nominal one were observed as well, suggesting the occurrence of an aggregation process. The presence of platinum in the dissolved form was not detected.
1 September 2019 in Science of The Total Environment
The growing use of nanoparticles in a wide range of products has resulted in their release into the aquatic environment; therefore, an understanding of the toxic effects of nanoparticles on aquatic organisms is of permanent importance. The aim of this study was to evaluate the toxicity of silver and platinum nanoparticles toward the freshwater microalga, Pseudokirchneriella subcapitata. Algal growth and photosynthetic pigments were determined to quantitate the effects of varying concentrations of Ag and Pt nanoparticles. The silver nanoparticles were much more toxic than the platinum ones. The concentrations causing total inhibition of algal growth were 5.0 and 22.2 mg L−1, respectively. Similar results were obtained by analyzing the concentration of photosynthetic pigments in P. subcapitata exposed to nanoparticles. Thus, simple spectrophotometric determination of chlorophyll is a convenient tool for the analysis of nanoparticle toxicity to algae.
Nanotechnology is a dynamically developing field of scientific and industrial interest across the entire world, and the commercialization of nanoparticles (NPs) is rapidly expanding. Incorporation of nanotechnologies into a range of manufactured goods results in increasing concern regarding the subsequent release of engineered NPs into the environment. One of the biggest threats of using NPs is the transfer and magnification of these particles in the trophic chain. The aim of the studies was the evaluation of the distribution of TiO2 NP contamination in the aquatic ecosystem under laboratory conditions. Bioaccumulation of TiO2 NPs by plants (Elodea canadensis) and fish (Danio rerio) in the source of contamination was investigated. The studies were focused on the consequences of short-term water contamination with TiO2 NPs and the secondary contamination of the components of the investigated model ecosystem (plants, sediments). It was found that in the fish and the plants exposed to NP contamination, the amount of Ti was higher than in the control, indicating an effective bioaccumulation of NPs or ions originating from NPs. It was clearly shown that the NPs present in the sediments are available to plants and fish. Additionally, the aquatic plants, an important trophic level in the food chain, can accumulate NPs and be a source of NPs for higher organisms. It was concluded that even an incidental contamination of water by NPs may result in long-term consequences induced by the release of NPs.
Nanoparticles (NPs) are commonly used, and concerns about their possible adverse effects are being voiced as well. However, little is known about the fates of NPs released to the environment. The aim of the study was to (i) evaluate the ability of Sinapis alba and Lepidium sativum plants to take up platinum nanoparticles (Pt-NPs) and translocate them to aboveground organs, (ii) compare the accumulation efficiency of different forms of platinum and (iii) identify the forms in which platinum is stored in plant tissues. Plants were cultivated on medium supplemented with different concentrations of Pt-NPs and [Pt(NH3)4](NO3)2. Platinum content in plants was determined using inductively coupled plasma mass spectrometry. For the identification of the presence of Pt-NPs in plant tissues, gamma spectrometry following iron irradiation was applied. It was found that L. sativum and S. alba are tolerant to applied concentrations of Pt-NPs and have an ability to take up platinum from the medium and translocate it to aboveground organs. The highest concentration of platinum was observed in plant roots (reaching 8.7 g kg−1 for S. alba). We tentatively conclude that platinum is accumulated as nanoparticles. The obtained results suggest future application of plants for phytoremediation and recovery of noble metal nanoparticles.
18 December 2018 in Journal of Analytical Atomic Spectrometry
In recent years, the increasing use of zinc oxide nanoparticles (ZnO NPs) in many consumer products and industrial applications made them a new potential source of zinc in the environment. After their release into the environment, ZnO NPs can undergo different transformations which are still poorly understood and may influence their potential toxicity. This study investigates for the first time the fate of zinc, supplied in the form of ZnO NPs and ZnCl2, taken up by a model edible plant (lettuce, Lactuca sativa L.) by means of different mass spectrometry techniques. Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) analysis showed the rapid dissolution of ZnO NPs in the growth medium used for cultivation of lettuce, confirming that only dissolved zinc, not intact NPs, is taken up by plants. Taking into account that the beneficial or toxic effects of zinc depend on its form accumulated by plants, it is crucial to identify the chemical forms of zinc and their distribution in edible plant tissues. Therefore, the second part of this work was focused on the study of zinc speciation in plants cultivated with ZnCl2 by using hyphenated techniques. The proposed approach based on two-dimensional chromatographic (size exclusion – SEC and hydrophilic interaction – HILIC) separation with parallel ICP-MS and ESI-qTOF-MS/ESI-FT-Orbitrap-MS detection allows the determination and identification of minor zinc complexes at environmentally relevant concentrations. Nicotianamine (NA) is shown to be the major ligand binding zinc in lettuce leaves, and the Zn–NA complex is responsible for more than 70% of the total zinc content extracted from lettuce leaves by means of ammonium acetate buffer.