This project on microplastics (MPs) will be directed to assess their impact on the ecological environment, especially in the Issyk-Kul Lake. Led by Institute of Chemistry and Phytotechnologies of NAS KR, the study will be conducted by scientists from biological research institution and aims to detect lake microplastics, develop ways to control their risks on the ecosystem, and propose solutions and actions to face this environmental threat. In the Issyk-Kul Lake, the abundance and the impact of macro and micro plastic is not known. In this project, project team will collect information for this lake focusing on the water column, the lakebed, the surface and the coastline, analyzing the problem and conducting a risk assessment on these areas with regards to the impact on selected lake species. Project team will also analyse the way in which the load could mitigate and reduce this microplastic problem.
Common additives of plastics are interesting both as potential tracers of microplastics, and important because they might constitute a pollution problem if/when they are released to the environment and taken up by organisms. Plastic products and plastic waste contain different additives in order to obtain the wanted properties of the products. There are hundreds of additives in the market, and their presence in the plastics can vary largely, from a few percentages and up to 50-60%. Currently, a number problem substances used in/as additives have been identified as bearing environmental and/or health risk, notably: bisphenol A (curing agent in polycarbonate and epoxy resins), brominated flame retardants, phthalates (plasticizers), chlorinated paraffins, pentachlolorophenol, toxic heavy metals (colorants and stabilizers): Hg, Pb, Cd, Cr. Among other historically infamous persistent organic pollutants (POPs) often related to polymer products are PCB, HBCD and nonylphenols. Among important emerging pollutants being of plastic related origin, and which will turn up in some microplastic particles, are perfluoro alkyl substances and organophosphorous flame retardants. Since additives are not usually bound to the polymer matrix, are of low molecular weight, and may be present in large amounts, they often account for the major leaching and emissions of chemical substances from plastic materials.
This project will investigate the uptake and impact of microplastic additives (MPAs), develop and apply laboratory methods for simulating environmental MPs degradation, and establish a decision support framework for polymer material threat mitigation. To reflect the ubiquitous nature of MPs pollution, the project will focus on freshwater and lake ecosystems. The fate and effects of MPs and MPAs will be studied using environmental conditions and species representing these ecosystems, including species from different trophic levels and a broad range of acute and sublethal endpoints. The role of biofouling and degradation on the adsorption of POPs to MPAs and the implications for subsequent toxicity will also be investigated.
Aim of the project is to understand the fate and toxicity of microplastics (MPs) and additives (MPAs) in a range of aquatic environments and develop a decision support framework for mitigating environmental impacts. Objectives of this project are the following:
· Develop methods for simulated degradation of polymers in aquatic environments.
· Develop and apply methods for characterising polymer degradation processes and products in different aquatic environments.
· Quantify persistent organic pollutant (POP) adsorption to MPs and assess the influence of MPs on POP toxicity.
· Explore the interaction mechanism between MP/MPA and dissolved organic matter (DOM) at a molecular level.
· Quantify MPA uptake, accumulation and excretion in species from multiple trophic levels and aquatic ecosystems.
· Determine acute and sublethal effects of MPs and MPA exposure in species from multiple trophic levels and aquatic ecosystems.
· To create intellectual ecological models for ecological risk assessment and risk-based decision making for aquatic ecosystems with particular focus to Issyk-Kul Lake.
To quantify and identify microplastics, additives and POP from freshwater and lakewater samples combined use of different techniques will be used as pyrolysis-GC/MS, FTIR spectroscopy, liquid chromatography (HPLC), thermogravimetric analysis with a solid-phase extraction (TGA-SPE) and thermal desorption gas chromatography mass spectrometer (TDS-GC/MS). Fluorescence and Fourier transform infrared analysis (FTIR) will be used to track the structural changes of DOM in its interaction process with MP and MPA. Experiments will be conducted using polystyrene/bisphenol/Pb and humic acids as the representative MP/MPAs and DOM, respectively.
To measure toxicological endpoints in different model test-organisms, bioassay responses will be obtained from organisms which represent different trophic levels: (i) producers (green algae and higher plant); (ii) consumers (crustacens and protozoan, mammalian cell culture), (iii) reducers (luminescent bacteria and pure culture of micromycete). Triad-based ecological risk assessment (ERA) including chemical, biological and ecotoxicological markers and multi-criteria decision analysis (MCDA) will be used to estimate the potential risk of water from microplastics.
The proposed study is closely related to the activities of project team. The basis of the development under this project proposal is previous studies of the project participants, in particular, concerning development of system for an ecological risk assessment and risk-based decision making for anthropogenic ecosystems, with particular focus to the former uranium-producing province. Team participants have been performing large-scale studies of binding and detoxifying properties of humic substances in respect to various ecotoxicants (heavy metals, atrazine, radionuclides, nanomaterials). Moreover, author of project proposal has been working with synthetic polymers in terms of structure and properties analysis. In addition, the team has excellent scientific experience in the field of development of technical approach for ecotoxicological assessment of environments
