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Sub-micron plastics (SMPs, size < 1 µm) are potentially taken up by plants. Serious concerns arise that how far SMPs can transfer from plants into food webs. Here, we show that lettuce takes up 250 nm gadolinium labelled polystyrene (PS) and polyvinyl chloride (PVC) SMPs from the soil. The polymer type influences the biodistribution of the particles in lettuce (roots and leaves) and the number of particles transferred from the plants to insects feeding on the treated lettuce. The SMPs were further transferred from insects to insect-feeding fish to accumulate mostly in the fish liver. No Gd was released from the particles upon biotransformation (formation of protein corona on the particles) in the plants or insects. However, Gd ion was detected in fish fed with PS-SMP treated insects, indicating the possible degradation of the particles. No biomagnification in fish was detected for either type of SMPs. We conclude that plastic particles can potentially transfer from soil into food webs and the chemical composition of plastics influences their biodistribution and trophic transfer in organisms. [Display omitted] • Lettuce takes up 250 nm polystyrene and polyvinyl chloride SMPs from the soil. • SMPs transfer from lettuce → insect → fish but no biomagnification has occurred. • The polymer type influences the biodistribution of SMPs in the organisms. • The SMPs accumulate mostly in the fish liver. [ABSTRACT FROM AUTHOR]

Exposure of aquatic organisms to micro- and nano-sized plastic debris in their environment has become an alarming concern. Besides having a number of potentially harmful impacts for individual organisms, plastic particles can also influence the phenotype and performance of their offspring. We tested whether the sperm pre-fertilization exposure to nanoplastic particles could affect offspring survival, size, and swimming performance in the European whitefish Coregonus lavaretus. We exposed sperm of ten whitefish males to three concentrations (0, 100 and 10 000 pcs spermatozoa−1) of 50 nm carboxyl-coated polystyrene spheres, recorded sperm motility parameters using computer assisted sperm analysis (CASA) and then fertilized the eggs of five females in all possible male-female combinations. Finally, we studied embryonic mortality, hatching time, size, and post-hatching swimming performance of the offspring. We found that highest concentration of plastic particles decreased sperm motility and offspring hatching time. Furthermore, sperm exposure to highest concentration of plastics reduced offspring body mass and impaired their swimming ability. This suggests that sperm pre-fertilization exposure to plastic pollution may decrease male fertilization potential and have important transgenerational impacts for offspring phenotype and performance. Our findings indicate that nanoplastics pollution may have significant ecological and evolutionary consequences in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

The presence of microplastics in aquatic ecosystems has recently received increased attention. Small plastic particles may resemble natural food items of larval fish and other aquatic organisms, and create strong selective pressures on the feeding traits in exposed populations. Here, we examined if larval ingestion of 90 μm polystyrene microspheres, in the presence of zooplankton (Artemia nauplii, mean length = 433 μm), shows adaptive variation in the European whitefish (Coregonus lavaretus). A full-factorial experimental breeding design allowed us to estimate the relative contributions of male (sire) and female (dam) parents and full-sib family variance in early feeding traits, and also genetic (co)variation between these traits. We also monitored the magnitude of intake and elimination of microplastics from the alimentary tracts of the larvae. In general, larval whitefish ingested small numbers of microplastics (mean = 1.8, range = 0–26 particles per larva), but ingestion was marginally affected by the dam, and more strongly by the full-sib family variation. Microsphere ingestion showed no statistically significant additive genetic variation, and thus, no heritability. Moreover, microsphere ingestion rate covaried positively with the ingestion of Artemia , further suggesting that larvae cannot adaptively avoid microsphere ingestion. Together with the detected strong genetic correlation between food intake and microplastic intake, the results suggest that larval fish do not readily possess additive genetic variation that would help them to adapt to the increasing pollution by microplastics. The conflict between feeding on natural food and avoiding microplastics deserves further attention. Image 1 • Ingestion of 90 μm polystyrene microspheres exhibits no additive genetic variation. • Vulnerability to microsphere ingestion is mostly determined by environmental effects. • Larvae appeared to ingest microplastics along with zooplankton. • Low potential for microplastic intake to evolve independently of food intake. The present work provides the first experimental evidence that microplastic feeding tendency in the presence of zooplankton shows no significant additive genetic variation, raising the concern that fish may not be able to adapt to the presence of plastic particles by actively avoiding them in their foraging. [ABSTRACT FROM AUTHOR]

Abstract: Temporal consistency of relative standard metabolic rate (rSMR) of individual Atlantic salmon Salmo salar juveniles in three stocks was investigated. The stocks differed in their geographical origin and natal habitat (fresh water, brackish water, seawater). Oxygen consumption measurements of hatchery-reared fish hatched in February 2005 were conducted three times: in early spring 2006, in autumn 2006, and in late spring 2007. The results partly disagreed and partly agreed with earlier studies, in which temporal consistency of SMR in juvenile salmonids have been addressed. In the first period from early spring to autumn, no correlation between rSMR statuses of individuals was found whereas in the second period from autumn to late spring, fish were mainly observed to maintain their relative SMR level indicating a significant repeatability of individual rSMR status over the latter period. Furthermore, a relationship between rSMR status and life history strategy was found: post-smolts and smolts had higher SMR than non-smolts. [Copyright &y& Elsevier]