Microplastics and sorbed contaminants – Trophic exposure in fish sensitive early life stages

Abstract

The present study evaluated very small microplastic particle (MPs) transfer to zebrafish and marine medaka larvae via prey experimentally exposed to MPs from the onset of feeding. Larvae were fed Paramecium or Artemia nauplii loaded with fluorescent 1-5 or 10-20 μm MP. Pollutant accumulation was analyzed by optically tracking of benzo [a]pyrene (BaP) and recording cyp1a transcription. Paramecium transferred 1-5 μm particles only, whereas Artemia efficiently transferred both MPs. Although zebrafish and medaka larvae fed from the onset of active food intake (2-3 dph, respectively) on Paramecium and from days 6-7 post-hatch on Artemia nauplii, neither MP accumulation nor translocation to tissues was detected. MP egestion started within few hours after ingestion. Cyp1a induction and fluorescent analyses proved BaP bioavailability after transfer via Paramecium and Artemia. Unicellular or plankton organisms ingest contaminants via MPS and transfer effectively these to sensitive early life-stages of vertebrates, giving rise to whole-life exposure.

Effects of microplastics on the feeding rates of larvae of a coastal fish: direct consumption, trophic transfer, and effects on growth and survival

“…This is consistent with high rates of ingestion of both microplastic colors by brine shrimp (see “ Results ” section) and the idea that brine shrimp nauplii are fairly indiscriminate eaters. Other studies have shown that ingestion of nanoplastics and microplastics by zooplankton is common (Cole et al 2013 ; Desforges et al 2015 ; Sun et al 2017 ; Cousin et al 2020 ), and that retention of microplastics is fairly low (Wang et al 2019 ), zooplankton as a group may be particularly susceptible to the negative effects of microplastic pollution. It is becoming increasingly clear that microplastics may be transferred up the food web (e.g., Setälä et al 2014 ; Cousin et al 2020 ; Hasegawa and Nakaoka 2021 ; Stienbarger et al 2021 ), more studies of the ecological effects of trophic transfer are needed.…”

“…Other studies have shown that ingestion of nanoplastics and microplastics by zooplankton is common (Cole et al 2013 ; Desforges et al 2015 ; Sun et al 2017 ; Cousin et al 2020 ), and that retention of microplastics is fairly low (Wang et al 2019 ), zooplankton as a group may be particularly susceptible to the negative effects of microplastic pollution. It is becoming increasingly clear that microplastics may be transferred up the food web (e.g., Setälä et al 2014 ; Cousin et al 2020 ; Hasegawa and Nakaoka 2021 ; Stienbarger et al 2021 ), more studies of the ecological effects of trophic transfer are needed. Our study found immediate effects on growth and a trend toward greater mortality when larval fish consume zooplankton that have ingested microplastics.…”

“…Although it was not part of our study, ingested microplastics that stay in the gut may interfere with feeding. Residence times of microplastics in the gastrointestinal tract are not well known, and egestion can occur as soon as several hours after microplastics exposure (Cousin et al 2020 ) and may take up to 49 days for total egestion in some species (e.g., Seriolella violacea ) depending on the size and type of microplastic (Mazurais et al 2015 ; Ory et al 2018 ). Mazurais et al ( 2015 ) reported that there was little effect of microplastic ingestion on sea bass larvae because of its high potential for egesting microplastics.…”

“…Although it was not part of our study, ingested microplastics that stay in the gut may interfere with feeding. Residence times of microplastics in the gastrointestinal tract are not well known, and egestion can occur as soon as several hours after microplastics exposure (Cousin et al 2020) and may take up to 49 days for total Fig. 4 Effects of trophic transfer of microplastics.…”

Influence of Particle Size on Ecotoxicity of Low-Density Polyethylene Microplastics, with and without Adsorbed Benzo-a-Pyrene, in Clam Scrobicularia plana

“…In addition to physical stress afforded by the ingestion of MPs resulting in laceration, inflammation processes and starvation, impacts are also devoted to the intake of additive or sorbed hazardous chemical contaminants adsorbed onto MPs’ surface, thus becoming a carrier for transporting and releasing substances in marine organisms [ 10 , 11 , 12 , 13 ].…”