Datazoo

Title: Ingested Nano- and Microplastic Particle Lengths and Surface Areas, dissected from salp guts, analyzed with Epifluorescence microscopy, collected aboard multiple cruises SEAPLEX in 2009, SKrillEx I in 2014, and SKrillEx II in 2015.
Abstract: Salps were collected on SKrillEx I and II during nightly transects in 202-μm mesh bongo tows, towed to approximately 200 m depth, and samples were preserved in 5% formaldehyde buffered with sodium tetraborate. We also used zooplankton samples collected on the August 2009 SEAPLEX cruise, where samples were collected using a manta net, 333-μm mesh, towed for 15 minutes at the surface, with samples preserved in 5% formaldehyde buffered with sodium tetraborate. Salps were identified to species, life history phase (oozooid or blastozooid), and measured for zooid length. The length of the stomach was measured, noted for degree of fullness, and dissected from each salp. Dissected salp stomachs were cut in half and placed in 15 mL of Milli-Q water for at least 24 hours to soften and release gut contents. The contents were then vacuum-filtered onto 5-μm pore polycarbonate filters with an additional 70 mL of Milli-Q water to aid in filtration. Those filters were analyzed with modified epifluoresecence microscopy techniques for microplastic particles. All microplastic particles were analyzed for plastic shape, length, surface area, and fluorescence.

Keywords: ecology, fluorescence, marine, oceans, particulates, plankton, California Current, epifluorescence microscopy, Microplastics, North Pacific Subtropical Gyre, salps, Microfibers
LTER Data System Record: http://dx.doi.org/10.6073/pasta/95be897e03d594bb679d3c6f7380ba75

Projects: California Current Ecosystem LTER
Creators: Brandon, Jennifer (jbrandon@wildbeaconconsulting.com)
Contact: CCE LTER Information Manager (ccelter.im@gmail.com)
Other Personnel: Sala, Linsey Method development and data analysis
Freibott, Alexandra Epifluorescence Microscopy expert

Data

table	lengths Secondary datatable of dataset, containing lengths of all plastic types ingested by salps collected on SEAPLEX, SKrillEx I, and SKrillEx II	Rows: 135 Columns: 25	View / Download
table	areas Secondary datatable of dataset, containing areas of all plastic types ingested by salps collected on SEAPLEX, SKrillEx I, and SKrillEx II	Rows: 134 Columns: 25	View / Download

Methods

Salp collection and dissection

Salps were collected on SKrillEx I and II during nightly transects with 202-μm mesh bongo nets, towed to approximately 200 m depth, and samples were preserved in 5% formaldehyde buffered with sodium tetraborate. We also used zooplankton samples collected on the August 2009 SEAPLEX cruise, where samples were collected using a manta net, 333-μm mesh, towed for 15 minutes at the surface, with samples preserved in 5% formaldehyde buffered with sodium tetraborate. Salps were identified to species, life history phase (oozooid or blastozooid), and measured for zooid length. The length of the stomach was measured, noted for degree of fullness, and dissected from each salp. It was also noted whether a fecal pellet could be seen forming at the end of the gut. We made the dissection incision above the top of the stomach so that no ingested material was released during dissection. Mucous nets and upper esophagus contents were not examined because any plastics found in these regions may have been consumed during net feeding or entered the salp’s oral siphon while in the sample jar and might not reflect in situ consumption of mini-microplastics.

Salp gut content analysis

Dissected salp stomachs were cut in half and placed in 15 mL of Milli-Q water for at least 24 hours to soften and release gut contents. The contents were then vacuum-filtered onto 5-μm pore polycarbonate filters with an additional 70 mL of Milli-Q water to aid in filtration. To avoid airborne contamination, the salps were kept in sealed sample jars until dissection, dissections were done carefully with salps out of sealed jars for as short of time as possible, salps were dissected in clean glass labware, exposed to continual ventilating air to avoid airborne fiber contamination, and then dissected guts were immediately placed in sealed scintillation vials until slide preparations. The filtering apparatus was all glass, so the filter never came in contact with laboratory plastic. A small volume of Milli-Q water was added to promote a good seal to the 20-μm support filter and sample filter. After seawater sample filtration, residual microplastics adhering to the aluminum foil were rinsed onto the sample filter with Milli-Q water. The 47 mm polycarbonate filter was then separated from the backing filter with metal forceps, mounted on a 50 mm glass slide with immersion oil on top, and two cover slips, 24 x 50mm, No. 2 thickness, applied to the slide.

Nano- and Microplastic Abundance

Using modified techniques of the Landry Lab's nano- and microplankton abundance, nano- and microplastic abundance will be measured. Slides will not be stained with any fluorochromes during filtration. These slides will be analyzed for plastic types (long fibers, short fibers, and fragments) with a Zeiss Axiovert 200 microscope equipped with a fully motorized stage and Apotome imaging workstation for automated processing, 3-D reconstruction and extended-field focus. Imaging software then estimates equivalent spherical diameters (ESD) and normalized particle size distributions (log ESD vs. log size; ~1000 particles/analysis). The length, area, type, and fluorescence of every particle is recorded.

California Current Ecosystem LTER

Ingested Nano- and Microplastic Particle Lengths and Surface Areas (SEAPLEX, SKrillEx I, and SKrillEx II)

Data

Methods

Protocols