0
Article Tier 2 Marine & Wildlife Sign in to save

Aging of microplastics promotes their ingestion by marine zooplankton

Environmental Pollution 2017 467 citations

AI summary Read the abstract

Researchers tested whether marine zooplankton prefer microplastics that have been aged in seawater over pristine ones, hypothesizing that biofilm formation makes particles more attractive. They found that several copepod species and life stages did indeed ingest aged microplastic beads at higher rates than new ones. The study suggests that natural biofilm coating on ocean microplastics may make them resemble food, increasing the likelihood that marine organisms will consume them.

Polymers
Study Type Environmental

Microplastics (<5 mm) are ubiquitous in the marine environment and are ingested by zooplankton with possible negative effects on survival, feeding, and fecundity. The majority of laboratory studies has used new and pristine microplastics to test their impacts, while aging processes such as weathering and biofouling alter the characteristics of plastic particles in the marine environment. We investigated zooplankton ingestion of polystyrene beads (15 and 30 μm) and fragments (≤30 μm), and tested the hypothesis that microplastics previously exposed to marine conditions (aged) are ingested at higher rates than pristine microplastics. Polystyrene beads were aged by soaking in natural local seawater for three weeks. Three zooplankton taxa ingested microplastics, excluding the copepod Pseudocalanus spp., but the proportions of individuals ingesting plastic and the number of particles ingested were taxon and life stage specific and dependent on plastic size. All stages of Calanus finmarchicus ingested polystyrene fragments. Aged microbeads were preferred over pristine ones by females of Acartia longiremis as well as juvenile copepodites CV and adults of Calanus finmarchicus. The preference for aged microplastics may be attributed to the formation of a biofilm. Such a coating, made up of natural microbes, may contain similar prey as the copepods feed on in the water column and secrete chemical exudates that aid chemodetection and thus increase the attractiveness of the particles as food items. Much of the ingested plastic was, however, egested within a short time period (2-4 h) and the survival of adult Calanus females was not affected in an 11-day exposure. Negative effects of microplastics ingestion were thus limited. Our findings emphasize, however, that aging plays an important role in the transformation of microplastics at sea and ingestion by grazers, and should thus be considered in future microplastics ingestion studies and estimates of microplastics transfer into the marine food web.

More Papers Like This

Article Tier 2

Microplastic pollution in aquatic environments may facilitate misfeeding by fish

AI summary Read the abstract

Researchers found that biofilm formation on microplastic surfaces in freshwater environments facilitates fish misidentification of plastics as food, with the probability of capture increasing significantly as biofilm aging progressed over weeks.

Article Tier 2

The role of microbe-microplastic associations in marine Nematode feeding behaviors

AI summary Read the abstract

Researchers found that microbial biofilms growing on microplastics influenced marine nematode feeding behavior, with nematodes showing preferential consumption of biofilm-coated particles, suggesting that microbial colonization plays a key role in why organisms ingest microplastics.

Article Tier 2

The plastic Trojan horse: Biofilms increase microplastic uptake in marine filter feeders impacting microbial transfer and organism health

AI summary Read the abstract

Researchers found that microplastics colonized by microbial biofilms, which better represent environmental conditions, are ingested at higher rates by marine filter feeders than clean, virgin microbeads typically used in laboratory studies. The biofilm coating also introduced potentially harmful bacteria into the organisms that consumed them. The study suggests that previous research using pristine microplastics may have underestimated both the uptake rate and biological risks of microplastic ingestion in marine ecosystems.

Article Tier 2

Species-specific microplastic ingestion responses to biofilm in Eastern Tropical Pacific zooplankton

AI summary Read the abstract

Scientists studying tiny ocean creatures (zooplankton) found that whether these organisms eat microplastic particles depends on both the species and whether the plastic has a coating of algae and bacteria (called biofilm) on it — one species preferred coated plastic, another preferred bare plastic, and a third didn't care either way. Since zooplankton are at the base of the ocean food chain, this matters because it shows microplastic pollution can enter marine food webs in unpredictable ways, which is relevant to understanding how plastics may eventually work their way up to the seafood humans eat.

Article Tier 2

The Behavior of Planktonic Copepods Minimizes the Entry of Microplastics in Marine Food Webs

AI summary Read the abstract

Researchers found that planktonic copepods across all major feeding behaviors ingested microplastics at rates up to ten times lower than similar-sized microalgae, suggesting that copepod feeding strategies naturally limit the entry of microplastics into marine food webs.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper