Dredging Operations and

Environmental Research

U.S. Army Corps of Engineers


A MicroPlastic Database for SEDiments

What is MP-Sed?

MP-Sed is a database that contains MP concentrations, sizes, shapes and polymer data for sediments across the globe. The goal of this database was to compile data from peer-reviewed literature to inform anthropogenic background concentrations in dredged sediment; however, the information housed in this database has broader applications for the research community. See Calomeni et al. 2023 for more information.

mpID Continent Subdivison Country System Waterbody Zone Area Tidal Zone Test Area Sample Time Sediment Sample Method Sediment Depth (cm) Extract Sediment Wt Extract Method Extract Chemical Extract Oxidizer No. of Extracts Inspection mp range (µm) mp/kg dw MP Unit Dominant Shapes Dominant Size Colors Polymers N MP Stat Notes Data Obtained From Abbrev. Reference DOI
mpID Continent Subdivison Country System Waterbody Zone Area Tidal Zone Test Area Sample Time Sediment Sample Method Sediment Depth (cm) Extract Sediment Wt Extract Method Extract Chemical Extract Oxidizer No. of Extracts Inspection mp range (µm) mp/kg dw MP Unit Dominant Shapes Dominant Size Colors Polymers N MP Stat Notes Data Obtained From Abbrev. Reference DOI

Data downloaded for use should be credited as follows: MP-SED: A MicroPlastic Databased for SEDiments. (Year). Environmental Laboratory, U.S. Army Engineer Research and Development Center. Retrieved (Month, day, Year) from https://doer.el.erdc.dren.mil/.

Database Summary Graphs
What is a microplastic?

There are multiple definitions for microplastics or MPs that generally capture sizes ranging from 1 µm to 20 µm as the lower size limit to 500 µm to 5,000 µm as the upper size limit. Nanoplastic is a term that characterizes even smaller plastics with 0.001 µm (1 nm) as the lower size limit and 0.1 µm (100 nm) to 1 µm (1,000 nm) as the upper limit.

Graphic showing the relative size of Bacteria = 1-10µm and Human hair = 100µm. A colored strip shows the size of a nanoplastic (dark orange to light orange) ranging from 0.001-0.1µm vs. a microplastic ranging from light blue to medium blue to light blue in the range from 1-100µm. Below is the scale labeled from 1nm or 0.001µm up to 100µm. THe scale is exponential.
A series of eight square microscopic images of nanoplastics that look like small irregular bits on the slide with a pale greenish background and blue, green or clear shreds of plastic or threads of plastic in view.
Why are microplastics in sediment?

Sediments are the ultimate repository for many contaminants and solid particulate matter (natural and anthropogenic). Scientists consider sediments to have a high potential for plastic contamination. Plastic particles may enter lake and riverine sediments from municipal wastewater treatment plants (e.g. MP beads, washing of clothes made from synthetic fibers), and road (e.g. tire ware), agricultural (e.g. plastic coated agrochemicals) and stormwater (e.g. artificial turn and rubber running tracks) runoff. Plastics may enter nearshore/estuarine sediments through transport from riverine environments and beach litter. Subtidal marine sediments may experience plastic contamination from nearshore environments as well as marine sources (e.g. plastic netting). Plastics within the environment may degrade into MPs or could be initially present as MPs.

Other microplastic resources:

ToMex - A data repository for microplastic toxicity developed by the Southern California Coastal Water Research Project. Access the database: https://microplastics.sccwrp.org/

Thornton Hampton L., M. P. et al. (2022). A living tool for the continued exploration of microplastic toxicity. Microplastics and Nanoplastics. DOI: 10.1186/s43591-022-00032-4.

NCEI Marine Microplastics – a database repository for microplastics in marine settings by National Centers for Environmental Information, National Oceanic and Atmospheric Administration.
Access the database: https://www.ncei.noaa.gov/products/microplastics

Hannah Ritchie and Max Roser (2018). Plastic Pollution. Published online at OurWorldInData.org. Retrieved from: https://ourworldindata.org/plastic-pollution [Online Resource]

DOER Projects:

Guidance for Communicating Risks of Microplastics and Nanoplastics in Dredged Sediments

Microplastics in Dredged Material

Data Field Definitions
Field Description
Abbrev. Reference An abbreviation of the reference citation is provided.
Colors Most common colors reported.
Continent Continents, usually considered to be seven: Africa, Antarctica, Asia, Europe, North America, Australia (Oceania), and South America.
Country A distinct and self-governing geographical and political entity with defined borders and sovereignty over its territory.
Data Obtained From Refers to how the data were obtained (e.g., from table or text - table/text; from a graph - interpolate graph) and to the specific table, graph, or page number the data were obtained from as well as sample identifier (e.g., Table 2, S2-Cox).
DOI Digital Object Identifier (DOI) is a unique alphanumeric string assigned to the scientific paper or academic publication, to provide a permanent and stable link to that document on the internet. Clicking on this should use the browser search feature to find the article.
Dominant Shape Refers to the most frequently encountered microplastic shape in the sample (i.e., fiber - fbr, film - flm, foam - fm, fragment - frgmnt, sphere - sphr).
Dominant Size Refers to the most frequently encountered microplastic size (e.g., <1 mm, <2 mm).
Extract Chemical Refers to the density separation solution (e.g., zinc chloride) and density (e.g., 1.5 g/ml).
Extract Method Refers to the major steps in the microplastic extraction process (e.g., 1-sieved, 2-density separated, 3-oxidized).
Extract Oxidizer Refers to the oxidizer used to remove organics from plastics and aid in identification. Example oxidizers include hydrogen peroxide or Fenton's reagent. If no oxidizer was used this will be blank or (none).
Extract Sediment Wt Refers to the weight of sediment used for microplastic extraction and whether the sediments was dry or wet (e.g., 50 g dry).
Inspection If spectroscopy was used to confirm plastic identity the method is displayed here (e.g., Raman, FTIR, Visual Inspection Only)
mp range (µm) Refers to either the size range of microplastics detected or targeted or to the method specific limits of detection.
MP Stat Refers to the descriptive statistic used for the microplastic quantity.
MP Unit Number of microplastics per kilogram of sediment dry weight
mp/kg dw Refers to the number of microplastics extracted from a sample and normalized to kilogram of sediment dry weight.
mpID Identification number automatically generated by the database.
N Refers to the number of samples analyzed for MP Stat.
No. of Extracts Refers to the number of times the extraction method was performed for each sample (e.g., one-time 1x, 2x, 3x, etc.).
Notes The note is used to provide additional information about any entry.
Polymers Most common polymers reported.
Sample Time Refers to the year, month, (e.g., September, October) and/or season (Fall, Spring) in which the sediment sample was collected.
Sediment Depth (cm) Refers to the depth range (e.g., 0-15 cm) collected from the uppermost layers of sediment or from layers within a core (e.g., 15-20 cm) collected from sediment below the surface of a body of water.
Sediment Sample Method Method used to collect sediment sample beneath the surface of a body of water.
Subdivision Refers to a lower-level administrative or geographical unit within a country. Common types include States, Provinces or Districts.
System Refers to higher level of organization from water body, adopting terms such as Marine, Estuarine, Riverine, Great Lakes, Lakes.
Test Area Refers to a specific geographic region or location that is selected for in-depth examination, research, analysis, or investigation. It is a defined space where authors focused their efforts to collect data. (e.g., a bay inside of a larger water body).
Tidal zone Refers to areas within a waterbody using terms such as subtidal, harbor, and port.
Waterbody A term used to describe any significant body of water, such as a river, lake, ocean, sea, pond, or any other substantial collection of water.
Zone Area Refers to areas within a waterbody using terms such as coastal, bottom, floodplain, nearshore, littoral, tributary, dredge prism.
Meet the Project Development Team

Calomeni, A., Wilkens, J., Boyda, J., Kennedy, A., and McQueen, A. (2023). Microplastic and nanoplastic risks in dredged sediments: From databases to strategic responses. Proceedings of the Western Dredging Association Dredging Summit & Expo ‘23, Las Vegas, NV, USA, July 17-20, 2023.

Wilkens, J. L., McQueen, A. D., LeMonte, J. J., and Suedel, B. C. (2020). Initial survey of microplastics in bottom sediments from United States waterways. Bulletin of environmental contamination and toxicology, 104, 15-20. https://doi.org/10.1007/s00128-019-02762-3

Last updated on 12/5/2023.