Nanoparticles in environment


Effect of water and wastewater treatment on the properties of engineered nanomaterials (ENMs) in the context of their fate, toxicity and interaction with other contaminants (SAFEnano) (H2020-MSCA-IF-2015, No. 699794) (PI - P. Oleszczuk)

Toxicity, bioaccumulation and speciation of inorganic nanoparticles in soils of different physicochemical properties (NCN Preludium, 2014/15/N/NZ9/02429) (PI: Izabela Jośko)

The aim of the project is the learning of the interactions between nanoparticles (NPs) and soil components and NPs and the living organisms.  Explanation of those mechanisms will lead to the acquisition of new knowledge and expansion of existing knowledge in the area of fate of NPs in the environment, including their bioavailability and bioaccumulation. The use of chemical and ecotoxicological methods in the research, in conjunction with the microscopic analyses verify the environmental risk resulting from the presence of NPs in soils. The acquired information will be useful for maintaining soil quality.

Research project impact In the face of intensive development of nanotechnology, apart from benefits new challenges and problems appear. Growing production and exploitation of nanoproducts determines the spread of nanoparticles (NPs) in the environment, including soils. NPs as a new contaminants needs to be deeply investigated. The assessment of bioavailability of NPs will indicate the retention duration in various soils and their potential to mobile to other elements of the environment. Additionally, the evaluation of bioaccumulation of NPs will point out a risk of food transfer. Monitoring fate of NPs in different soils will help in verify a threat of the presence of NPs in the soil environment. Thanks to planned research, the proper action (for example agrotechnical practices) maybe taken to maintain soil quality. The effective soil protection will result in proper functioning other ecosystems as well as health humans.

Selected references:

Jośko I., Oleszczuk P. The bioavailability and toxicity of ZnO and Ni nanoparticles and their bulk counterparts in different sediments. J. Soils Sediments 16 (2016) 1798–1808.

In view of the above information it is necessary to undertake research on the effect of water treatment processes on the properties of ENMs. This will not only expand our current knowledge in this area, but it will also permit the identification of actual threats related with the use of ENMs. This in turn will permit the presentation of suitable solutions for the authorities responsible for environmental safety on Europe.

The primary aim of the present study will be to attempt to estimate what changes different ENMs (coated and nanohybrids) will undergo during water and wastewater treatment and how these changes will affect ENMs fate, toxicity and interaction with other contaminants. Specifically, I will:

  1. 1.Enhance our knowledge of the ENMs transformation during water and wastewater treatment (WP1).

  2. 2.Enhance our knowledge how ENMs transformation will affect their fate in the environment on the basis of laboratory and mesocosm experiments (WP2).

  3. 3.Enhance our knowledge about interaction between well-known contaminants and ENMs (WP3).

  4. 4.Perform risk assessment of ENMs in the context of their transformation (WP4).

The proposed study will be the first which investigate how various water and wastewater treatment methods will influence the physicochemical and ecotoxicological properties of ENMs. Recognition of this problem has an extremely important aspect of cognition in a situation of increasing ENMs production. Acquired new knowledge on this topic will lead to a better understanding of the mechanisms and processes in the environment. The research will contribute to a broad base of knowledge that will be the basis for solving of known or expected future problems related to the use of ENMs.

Behavior of engineered nanomaterials (ENMs) in the environment differs from the pathways observed for larger particles. Due to the special properties of ENMs and a wide range of their applications, attempts are made to estimate the fate of ENMs in the environment and transformations during their use and storage. The release of ENMs may occur during the use of materials containing nanoparticles, their processing or disposal and storage. It is assumed that the major part of ENMs gets into the environment with wastewater. During their transport and release into the environment, ENMs may undergo different transformations, e.g. oxidation and reduction, dissolution, adsorption, biotransformation, aggregation, and deposition. Those transformations may lead to changes in the properties of ENMs. As released ENMs will firstly get into wastewaters, one can expect that they will be subject to various processes of transformation there. Moreover, ENMs are commonly produced with an organic capping agent or stabilizer. Moreover recent focus on material synthesis and development at the nano-scale shows a clear shift from single material processing toward hierarchical assemblages (nanohybrids). Transformations of the material (coated and nanohybrids) can therefore affect the core material, the capping agent, or both. While publications tracing the fate of ENMs during wastewater treatment appear more and more frequently we currently lack sufficient knowledge of the types, rates, and extent of transformations expected for ENMs. By extension, we also fail to understand the impact of those transformations on the fate, transport, and toxicity of ENMs. To correctly forecast the environmental and human health risks associated with these materials, we must endeavor to broaden our knowledge of the transformations of ENMs. The latest research shows  that in wastewater treatment plants certain ENMs may undergo the processes of sulfidation, which has a detoxifying effect on ENMs. However other research demonstrated that sulphur and selenium in some metal sulphides and metal selenides (major components of quantum dots) are susceptible to oxidation that may release soluble toxic metal ions such as Cd. To date, studies on the impact of various processes on the transformation of ENMs are mainly focused on sulfidation. Broader description of the problem is not possible because other data does not exist in this area of research, especially when it comes to the transformation of nanoparticles in wastewater treatment plants. To our best knowledge the study will be the first in this area. Underestimation of the risk related to ENMs may create a serious threat to the environment. Our latest studies also demonstrated that treatment of CNTs with H2O2 and/or UV affected their properties. This effect, however, was different depending on the functionalization of CNTs and also on the factor used (UV and/or H2O2). H2O2 plays a key role as a factor modifying the surface of CNT-OHs, whereas the properties of CNT-COOHs were most affected by UV rays. A shortening of the nanotubes, exfoliation, the opening of their ends (Figure), and changes in the surface charge were observed as a result of the action of UV and/or H2O2. The changes in observed parameters may influence the stability of the aqueous suspensions of CNTs and adsorption of 

Selected references:

  1. (1)Czech B., Oleszczuk P., Wiącek A. Advanced oxidation (H2O2 and/or UV) of functionalized carbon nanotubes (CNT-OH and CNT-COOH) and its influence on CNTs stabilization in water and tannic acid solution. Environ. Pollut. 200 (2015) 161-167.

  2. (2)Czech B., Oleszczuk P., Wiącek A. Barczak M. Water treatment by H2O2 and/or UV affects carbon nanotubes (CNTs) properties and fate in water and tannic acid solution. Environ. Sci. Poll. Res. 22 (2015) 20198-20206.

  3. (3)Czech B., Oleszczuk P. Sorption of diclofenac and naproxen onto MWCNT in model wastewater treated by H2O2 and/or UV. Chemosphere 149 (2016) 272-278.

Influence of the addition of CNT on photocatalytic properties of TiO2 in the removal of pharmaceuticals

from water and wastewater (2017/01/X/ST4/00199) (Miniatura, NCN) (PI - dr Bożena Czech)

The presence of pharmaceuticals in water and treated wastewater indicates that the currently applied wastewater treatment methods are ineffective in the removal of those pollutants. There is a need to develop new methods of pharmaceutical removal from water matrix. Among various tested, Advanced Oxidation Processes seem to be the most effective. They enable to remove most of organic and inorganic pollutants using different oxidizing agents. During photocatalysis, both the reduction and oxidation of pollutants occurs on the surface of the photocatalyst (mainly TiO2). Despite numerous  advantages, TiO2 possesses a main drawback: it is active only under UV irradiation. In the last years a lot of studies have been performed to obtain a new TiO2 based photocatalyst active under visible light irradiation. Addition of multiwalled carbon nanotubes (MWCNT) into TiO2 results in increased number of active sites, reduced e-/h+ recombination and increased visible light induced activity. Previous studies have been performed over SiO2-TiO2 modified by the addition of carboxyl functionalized MWCNT (0.15-17.8 wt%). The high activity of tested nanocomposites in the removal of model pollutants (phenol, methyl orange) during UV or Vis irradiation was also confirmed during carbamazepine removal. As the addition of MWCNT–COOH caused an increase of the activity of TiO2 nanocomposites, it seems to be interesting to determine the effect of other carbon nanotubes on TiO2 visible light induced photocatalytic activity. During the project various carbon nanotubes (SWCNT, MWCNT, MWCNT-OH) will be added to TiO2. The obtained nanocomposites will be characterized and tested during removal of pharmaceuticals from water. The toxicity of untreated and finally treated wastewater will performed using Vibrio fischeri as reference water organism.

Selected references:

  1. (1)B. Czech, W. Buda, P. Oleszczuk, MWCNT–TiO2–SiO2 nanocomposites possessing the photocatalytic activity in UVA and UVC, Appl. Catal. B Environ. 162 (2015) 564–572.

  2. (2)B. Czech, W. Buda, Photocatalytic treatment of pharmaceutical wastewater using new multiwall-carbon nanotubes/TiO2/SiO2 nanocomposites, Environ. Res. 137 (2015) 176–184.