Modelling mussel (<i>Mytilus spp.</i>) microplastic accumulation

Abstract

Abstract. Microplastics (MPs) are a contaminant of growing concern due to their widespread distribution and interactions with marine species, such as filter feeders. To investigate the MPs accumulation in wild and cultured mussels, a dynamic energy budget (DEB) model was developed and validated with the available field data of Mytilus edulis (M. edulis, wild) from the North Sea and Mytilus galloprovincialis (M. galloprovincialis, cultured) from the northern Ionian Sea. Towards a generic DEB model, the site-specific model parameter, half-saturation coefficient (Xk), was applied as a power function of food density for the cultured mussel, while for the wild mussel it was calibrated to a constant value. The DEB-accumulation model simulated the uptake and excretion rate of MPs, taking into account environmental characteristics (temperature and chlorophyll a). An accumulation of MPs equal to 0.53 particles per individual (fresh tissue mass 1.9 g) and 0.91 particles per individual (fresh tissue mass 3.3 g) was simulated for the wild and cultured mussel after 4 and 1 years respectively, in agreement with the field data. The inverse experiments investigating the depuration time of the wild and cultured mussel in a clean-from-MPs environment showed a 90 % removal of MPs load after 2.5 and 12 d respectively. Furthermore, sensitivity tests on model parameters and forcing functions highlighted that besides MPs concentration, the accumulation is highly dependent on temperature and chlorophyll a of the surrounding environment. For this reason, an empirical equation was found, directly relating the environmental concentration of MPs, with the seawater temperature, chlorophyll a, and the mussel's soft tissue MPs load.

Where are we? Towards an understanding of the selective accumulation of microplastics in mussels

“…A breakthrough in the detection method of microplastics with smaller particle size (1-20 μm) will also contribute to collecting field evidence of particle translocation, especially in the hemolymph. Promisingly, Stamataki et al (2020) have used a dynamic energy budget model to study the relationship between microplastics accumulation in mussels and characteristics of mussel's surrounding environment, which shows high seasonal fluctuations. This brings a new research approach and more comprehensive models can be envisaged in future studies.…”

Review on the distribution of microplastics in the oceans and its impacts: Need for modeling-based approach to investigate the transport and risk of microplastic pollution

“…Further, specific models to assess the risk of microplastic pollution on marine organisms are not available. The studies conducted so far were conducted with Genereic DEB accumulation model [185], linear regression model [186], R-Software [26] and regression model [187]. Further, it is impossible to predict the risks of ingesting microplastics by marine organisms due to lack of measured data to validate the models.…”

Dynamic Energy Budget model suggests feeding constraints and physiological stress in black-lip pearl oysters, 5 years post mass-mortality event

“…Similarly, the dose-dependent toxic effects of microplastics or phytotoxins can be computed on the basis of a variable somatic maintenance rate parameter (Pousse et al, 2019). Similar developments could be implemented in the model of P. margaritifera to account for variation in food 13 type, including the presence of natural and exotic (e.g., microplastics; Gardon et al, 2018;Stamataki et al, 2020) inorganic matter, and toxic compounds in tropical lagoons. Resolving these components will improve the model's accuracy and broaden its scope (Sangare et al, 2020).…”