Papers

Plastics in the Marine Environment

This review traces nearly 50 years of research on plastic contamination in the oceans, from early sightings of debris to the current understanding of microplastic pollution spanning all marine habitats. Researchers highlight that plastics have been found in sizes from microns to meters, in locations from the sea surface to the deep ocean floor. The study emphasizes that despite growing awareness, significant gaps remain in understanding the full ecological and chemical impacts of marine plastic pollution.

The United States’ contribution of plastic waste to land and ocean

Researchers found that the United States generated the largest amount of plastic waste of any country in 2016 at 42 million metric tons, with a significant portion being illegally dumped or exported to countries with poor waste management. The study estimates that between 0.91 and 2.24 million metric tons of U.S. plastic waste ended up in the environment, highlighting the need for improved domestic waste reduction strategies.

Sunlight-Driven Photochemical Removal of Polypropylene Microplastics from Surface Waters Follows Linear Kinetics and Does Not Result in Fragmentation

Researchers tracked what happens to small polypropylene microplastics when exposed to sunlight over extended periods. The study found that sunlight steadily breaks down the plastic into dissolved organic carbon following a predictable linear pattern, and importantly, this process did not cause the microplastics to fragment into smaller particles, suggesting photodegradation may actually reduce rather than multiply microplastic pollution at the water surface.

Toward the Integrated Marine Debris Observing System

Researchers proposed a framework for an integrated marine debris observing system that would combine remote sensing, in situ measurements, and computer modeling to monitor plastic pollution globally. The study outlines how optical sensors, satellite imagery, and citizen science programs could work together to track debris sources, pathways, and accumulation patterns. The system aims to support policy decisions and operational cleanup efforts by providing reliable long-term data on the state of ocean plastic pollution.

A global inventory of small floating plastic debris

Researchers compiled a global inventory of small floating plastic debris from ocean surface sampling expeditions, estimating the total abundance and mass of floating microplastics and identifying the major oceanic accumulation zones.

The effect of wind mixing on the vertical distribution of buoyant plastic debris

Researchers modeled and measured how wind mixing affects the vertical distribution of buoyant plastic debris in the ocean, finding that turbulent mixing drives plastics below the surface and explains why surface sampling underestimates total plastic concentrations.

Microplastics segregation by rise velocity at the ocean surface

This study modeled the competing forces of particle buoyancy and turbulent mixing that control the vertical distribution of microplastics in the ocean surface layer, finding that particle rise velocity is the key variable that segregates plastic types and determines how they distribute relative to surface and subsurface measurements.

All is not lost: deriving a top-down mass budget of plastic at sea

Using a top-down mass budget approach, this study estimated how much plastic is present in the ocean by accounting for known inputs and fragmentation processes. The analysis helps identify where plastic mass is "missing" — whether through burial, beaching, or degradation — a key question for understanding the long-term fate of ocean plastic pollution.

The biogeography of the Plastisphere: implications for policy

This review examined the biogeography of the "plastisphere" — the communities of microorganisms living on floating plastic debris — and discussed its implications for marine policy. Because plastic surfaces carry unique, potentially invasive microbial communities across ocean basins, the authors argue that plastic pollution represents a vector for biological invasions with policy significance.

Accelerated degradation of low-density polyethylene in air and in sea water

UV-accelerated weathering of low-density polyethylene in air and floating in seawater was compared using FTIR depth profiling, finding that oxidation was diffusion-controlled in both media and localized to a thin surface layer, but that seawater slowed the overall degradation rate.

Distribution of Surface Plastic Debris in the Eastern Pacific Ocean from an 11-Year Data Set

Analysis of over 2,500 plankton net tows in the eastern Pacific Ocean from 2001 to 2012 documented a persistent plastic accumulation zone in the North Pacific subtropical gyre corresponding to the predicted convergence zone of ocean currents. The 11-year dataset reveals the long-term stability of this "garbage patch" and its distinct seasonal and interannual variability.

Relative exposure to microplastics and prey for a pelagic forage fish

Researchers quantified the relative exposure of Northern Anchovy to microplastics versus their natural zooplankton prey in the California Current, finding a median ratio of 1 microplastic per 3,399 zooplankton. Juvenile anchovies had a higher relative microplastic exposure than adults, and offshore habitats and winter conditions were associated with peak exposure.

Gooseneck barnacles ( Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre

Researchers examined the gut contents of gooseneck barnacles (Lepas spp.) collected from floating debris in the North Pacific Subtropical Gyre and found that all individuals had ingested microplastic particles. The findings demonstrate that suspension-feeding invertebrates colonizing floating plastic debris are directly exposed to and ingest microplastics, representing a pathway for plastic entry into open-ocean food webs.

Plastic Marine Pollution in the Gulf of Maine

A long-running monitoring program in the Gulf of Maine, tracking microplastics in plankton nets since 1987 alongside 20 years of shoreline cleanup data, found low but persistent concentrations of small floating plastic particles and continued accumulation of larger plastic debris on remote coastlines. The study suggests that microplastics represent a compounding environmental stressor for a marine ecosystem already under pressure from rapid ocean warming, and recommends policies targeting littering and at-sea plastic disposal.

The future of ocean plastics: designing diverse collaboration frameworks

This paper drew on an international workshop of early career ocean professionals to propose diverse collaboration frameworks for stakeholder engagement in ocean plastic pollution research, emphasizing inclusive, cross-disciplinary approaches to addressing marine plastic challenges.

Contrasting Size Dependence of Photochemical Lifetimes of Polypropylene and Expanded Polystyrene Microplastics in Surface Waters

Researchers found that photochemical dissolution of polypropylene and expanded polystyrene microplastics in surface waters does not scale linearly with surface-area-to-volume ratio as particle size decreases. Instead, the two polymers show contrasting size-dependent photochemical lifetimes, suggesting particle size and polymer type must both be considered when modeling plastic persistence in aquatic environments.

Passive buoyant tracers in the ocean surface boundary layer: 2. Observations and simulations of microplastic marine debris

Using ocean computer models calibrated against real-world observations, this study showed how wave mixing and other physical processes push buoyant microplastics below the ocean surface, explaining why less plastic is detected at the surface than expected. These models are critical for estimating where microplastic pollution is truly accumulating in the ocean.

Evidence for the Influence of Surface Heat Fluxes on Turbulent Mixing of Microplastic Marine Debris

This oceanographic study found that microplastic concentrations at the ocean surface increase during daytime heating and decrease at night when temperature-driven turbulence pulls floating plastics deeper. The findings help explain why surface measurements of ocean plastic may underestimate total plastic loads in the water column.

INTO THE MED: Searching for Microplastics from Space to Deep-Sea

Teen activism leads to local laws banning single-use plastics: a two-year experiential learning journey

High school students in Massachusetts spent two years petitioning their local government to ban thin plastic bags and single-use plastic water bottles under 1 liter, ultimately succeeding and demonstrating how youth environmental activism combined with civic education can translate global plastic pollution concerns into tangible local policy change.

Far more microplastics floating in oceans than thought

Peer Review #1 of "Gooseneck barnacles (Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre (v0.1)"

This peer review evaluated a study on microplastic ingestion by gooseneck barnacles (Lepas spp.) in the North Pacific Subtropical Gyre, where researchers examined the gastrointestinal tracts of 385 barnacles associated with floating debris in this plastic-accumulating region. The study was the first to document microplastic ingestion by a rafting invertebrate in the gyre, revealing that plastic exposure extends through the entire floating debris community.

Peer Review #2 of "Gooseneck barnacles (Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre (v0.1)"

This second peer review also evaluated the gooseneck barnacle microplastic ingestion study from the North Pacific Subtropical Gyre, providing independent scientific assessment of the methodology and findings. The peer review process ensures that published research on microplastic ingestion by marine organisms meets scientific standards before contributing to the evidence base.

Using Physical and Chemical Characteristics of Floating Microplastics to Investigate Their Weathering History