dc.description.abstract |
Microplastics have been reported to be present in zooplankton, yet questions persist regarding their fate and
dynamics within biota. We selected the commercial mysid shrimp, Mesopodopsis orientalis, as the focal
zooplankton for this study due to their crucial role in our study area, the Inner Gulf of Thailand in January 2022.
We investigated the presence of microplastics in mysid bodies and fecal pellets, examining both attached
microplastics on external body parts and those ingested. In addition, we conducted microplastic feeding experiments, exposing mysids to various treatments of microplastics. The results of the field investigation indicate
that mysids exhibited an average of 0.12 ± 0.03 microplastic items/mysid from whole-body samples. The shape,
type, and color of microplastics found in mysids were similar to those present in seawater, with blue PET
microfibers being the most prevalent. Our observations on live mysids revealed that microplastics were acquired
through ingestion and adherence to appendages and exoskeletons. Microplastics were observed in mysid’s fecal
pellets at 0.09 ± 0.03 items/mysid, while microplastics adhering to the mysid’s body and appendages were
observed at 0.10 ± 0.04 items/mysid. The sizes of microplastics extracted from preserved mysids ranged from
58 μm to 4669 μm, with median of 507 μm. The laboratory experiments revealed that the presence of microalgae
enhanced microplastic ingestion in mysids; microplastics incubated with a cyanobacterium, Oscillatoria sp., and
diatom Navicula sp. significantly increased the number of microplastic particles ingested by mysids. This study
showed that microplastics can be more ingested in mysids, especially when food items are present. Microplastic
fate in these animals may involve expulsion into the environment or adherence, potentially facilitating their
transfer up the marine food web. |
vi,en |