This study examined the potential of polyethylene microplastic particles to act as a vector for fluoranthene on mysids. Continuously growing plastic production in last 60 years combined with improper disposal and the long durability of plastic had led of plastic becoming a serious concern as an environmental pollutant. The negative effects caused by ingestion have been reported in many studies and refers to changes in feeding behavior, death due to false satiation, damages to feeding appendages etc. The characteristic of polyethylene microplastic particles to bind hydrophobic compounds was confirmed previously in many studies. Therefore, one of the hazard for microplastic particles is to act as a carrier or vector for PAHs such as fluoranthene, potentially increasing the uptake and bioaccumulation of the PAH to in the aquatic organisms. Fluoranthene is one of the most abundant PAHs and was used as model toxicant to study changes on accumulation dynamics in the presence of microplastic particles. The test organism was Mysida sp. - a shrimp like crustacea. The experiment consisted of both - influx and efflux measurements. Influx experiment included exposure of 3 different treatments: a) fluoranthene only (Fl only), b) Co-exposure (Co-expo) and c) Incubated fluoranthene + microplastic particles (Inc Fl+MP). Each of treatments were exposure to 5 fluoranthene concentrations (100 – 500 µg/l) over 24 h period. Efflux was calculated based on measurements of fluoranthene concentrations at specific time points in mysids exposed to 300 µg/l fluoranthene concentration over 7 days period. The microplastic sorption/desorption experiment to fluoranthene was performed in order to provide context for the results from mysids. The obtained results showed that uptake rate of fluoranthene is 18-43 times higher for Co-exposure treatment than for Fl only and Inc FL+MP treatments (ku equals to 0.1044, 0.0056 and 0.0024 L g-1d-1 respectively). On the other hand, rates of loss ke are on comparable level for all treatment groups (0.0759, -0.4535, -0.3156 d-1 for Fl only, Co-expo and Inc Fl+MP respectively). This suggests that MP presence has influence on fluoranthene accumulation: uptake and elimination, and act as a vector, although results are inconclusive.
|Uddannelser||Miljørisiko, (Bachelor/kandidatuddannelse) Kandidat|