Mattrygghet: Effects of micro/nanoplastics and contaminated micro/nanoplastics on food safety of fish

Overflaten til plast binder seg lett til fettløselige miljøgifter. Mikroplast har en stor overflate i forhold til volum, og kan derfor fungere som en "vektor" for forurensning, fange miljøgifter og la dem bevege seg rundt i miljøet og bli spist av dyr. Prosjektet skal delvis svare på spørsmålet om hvordan miljøgiftene binder seg til mikroplast, om de små mikroplastene tar opp mer forurensende stoffer enn større mikroplast, og hvor rask mikroplast tar opp organiske forurensninger. Mikroplast kan hemme vekst og kroppsutvikling, påvirke fiskens næringsopptak og atferd, være skadelig for reproduksjon og immunsystem, forårsake genetisk skade etc. Disse observasjonene mangler imidlertid ofte systematisk undersøkelse under kontrollerte forhold. For å vitenskapelig dokumentere denne effekten, skal prosjektet bruke mikroplast med kjente kjemiske tilsetninger og kvantitativt studere effekten av disse stoffene og mikroplast på fiskens vekst.

This project investigates microplastics (MPs) in aquatic and terrestrial environments, exploring their distribution, environmental impact, and potential threats to human health. Key outcomes include the development of advanced methods for detecting MPs, studies on their adsorption behaviors, and the assessment of their biological effects on ecosystems. 1. Analytical Methods for MP Detection The project advanced methods like Gel Permeation Chromatography (GPC) and Nuclear Magnetic Resonance (qNMR) to detect and quantify microplastics in environmental samples such as water, soil, and sediment. These high-sensitivity techniques enable precise identification of MPs at low concentrations, enhancing environmental monitoring. The ability to assess multiple media is crucial for understanding how MPs spread through ecosystems and their long-term impacts. 2. Adsorption Behavior and Environmental Implications MPs can adsorb pollutants like heavy metals and organic chemicals, which may intensify their ecological effects. The research showed that MPs with larger surface areas and those exposed to UV degradation have higher adsorption capacities. Biodegradable plastics (PBS, PBAT, PLA) displayed distinct adsorption patterns, indicating different environmental fates. These findings highlight the potential of MPs to carry harmful contaminants, compounding environmental and health risks. 3. Microplastics in Aquatic Ecosystems Field studies in Bosten Lake showed high concentrations of MPs near urban areas, linking human activity to pollution levels. Fish tissue analyses revealed MP accumulation in digestive organs, suggesting bioaccumulation through the food chain. Exposure led to physiological stress in fish, including liver damage and metabolic disturbances, raising concerns about the impacts on both aquatic life and human health through seafood consumption. 4. Biological Risks of Polluted Microplastics MPs contaminated with chemicals (e.g., dyes, antibiotics) posed greater biological risks. Pollutants leached from MPs into surrounding environments, affecting organisms and amplifying toxic effects. This emphasizes the need to assess MPs not only as pollutants but also as vectors for chemical contaminants, increasing their ecological and toxicological risks. 5. Risk Assessment and Public Health Implications The project developed a risk assessment model to evaluate the environmental and health risks of MPs, incorporating pollutant adsorption and bioaccumulation data. The potential for MPs to enter the food chain through aquatic organisms presents significant public health concerns, urging stronger regulatory measures for plastic disposal and chemical pollution.

According to the statistics by FAO, fish as a source of food provides 15% high-quality protein for 4.3 billion people. The living environment of fish is increasingly affected by micro/nanoplastics (MNPs), which leads to issues in food safety. Therefore, understanding MNPs contamination is urgent. In this proposal, the adsorption of pollutants by MNPs and their toxicity to fish will be systematically studied through elegant experimental designs. We have selected four plastics with different chemical nature, and using laboratory simulated aging, we study how MNPs particle size is related to the different chemical nature of the plastics, so as to further study the adsorption thermodynamics and kinetics of chosen pollutants on MNPs. We further plan to investigate the influence of MNPs on the growth development of crucian carp. Meanwhile, we will compare the influence of pollutant-adsorbed-MNPs on the growth development of crucian carp and analyze the distribution and enrichment characteristics of MNPs in fish tissues. MNPs are difficult to isolate and characterize. Therefore, we will further explore the possibility of developing new methodologies for quantitative analysis of MNPs. In this regard, we focus on using NMR and GPC. Norway has ambition to intensify aquaculture production to fulfill a growing demand, and a large number of Norwegian seafood will appear on dining tables in China. Therefore, it is necessary for both countries to understand the pollution degree and regularity of MNPs in fish, and guarantee the food safety. This study is composed of three main units, and all parties will use their strength to systematically study the physicochemical properties of MNPs, their developmental toxicity to fish, and their new separation and analysis methods under ideal controlled conditions in our laboratories. The research results will make a breakthrough contribution to the elaboration of the pollution mode, pollution enrichment rule and analysis methods of MNPs.