Microplastic ingestion by Daphnia magna and its enhancement on algal growth,

Science of The Total Environment,
Volume 633,
2018,
Pages 500-507,
ISSN 0048-9697,

Abstract:

The rapid increase in plastic use over the last few decades
has resulted in plastic pollution in freshwater and marine ecosystems.
However, more attention has been paid to plastic pollution in marine
ecosystems than to freshwater ecosystems. This research determined
microplastic ingestion by Daphnia magna and the potential effect of
microplastics on the organism’s survival and reproduction. The study
also examined the potential of microplastics to enhance algal growth in
support of understanding effects of microplastic ingestion on the
organism. When exposed to 25, 50, and 100mg/L fluorescent green
polyethylene microbeads at size of 63–75μm, D. magna ingested
significant amount of plastic microbeads. The number of ingested beads
increased with increasing particle concentration and exposure time.
However, no significant effect on survival and reproduction was observed
although the gut of D. magna was filled with plastic microbeads. In the
algal experiment, Raphidocelis subcapitata grew more in the exposure
media with the present of plastic microbeads than without plastic
microbeads. This result suggests that plastic microbeads could serve as
substrates for R. subcapitata to grow. Raphidocelis subcapitata then
could be transferred to the organism’s gut and provided energy for
survival and reproduction. Results of the present study add to the
literature of microplastic ingestion by aquatic organisms. Caution
should be taken when interpreting hazards of microplastics based on
ingestion, such as the measurement unit and the presence of algae in the
environment.

https://drive.google.com/open?id=1nTftG0NvCpA2OD3R-RZviFxCdxewU6Bd
https://doi.org/10.1016/j.scitotenv.2018.03.176.(http://www.sciencedirect.com/science/article/pii/S0048969718309355)

The post Microplastic ingestion by Daphnia magna and its enhancement on algal growth appeared first on One Earth - One Ocean e. V..

Toxicological interactions induced by chronic exposure to gold nanoparticles and microplastics
mixtures in Daphnia magna,

Science of The Total Environment,
Volumes 628–629,
2018,
Pages 474-483,
ISSN 0048-9697,

Abstract:

The effects of emerging environmental contaminants on human and environmental health is of high concern, especially those potentially induced by mixtures. The main goal of the present study was to assess the chronic effects of mixtures of citrate stabilized ≈5 nm gold nanoparticles (AuNP) and 1–5μm microplastics (MP) on Daphnia magna.
A 21-day bioassay was carried out. The effect criteria were parental mortality, somatic growth and several reproductive parameters. AuNP induced parental mortality, reduced the total offspring and caused immobile juveniles and aborted eggs. MP induced parental mortality, delayed the first brood release, decreased the number of broods released, the total offspring, and caused immobile juveniles. All the
mixtures caused higher toxicity than AuNP and MP alone. Based on parental mortality, evidences of antagonism between AuNP and MP were observed at low concentrations of both mixture components, whereas
evidences of synergism at high concentrations were found.
Chronic (21-day) exposure of D. magna to AuNPs, MP, and their mixtures can impair development, reproduction, ultimately leading to death.

https://drive.google.com/open?id=1feyLRjOT9_UMlyAvJ_4FCLZKfp2lCk-L

https://doi.org/10.1016/j.scitotenv.2018.02.081.(http://www.sciencedirect.com/science/article/pii/S0048969718304716)

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Transgenerational effects and recovery of microplastics exposure in model populations of the
freshwater cladoceran Daphnia magna Straus,

Science of The Total Environment, Volumes 631–632, 1 August 2018, Pages 421-428, ISSN 0048-9697,

Abstract:

The environmental contamination by microplastics is a global challenge to ecosystem and human health, and the knowledge on the long-term effects of such particles is limited. Thus, the effects of microplastics and post-exposure recovery were investigated over 4 generations (F0, F1, F2, F3) using Daphnia magna as model. Effect criteria were parental mortality, growth, several reproductive parameters, and population growth rate.
Microplastics exposure (0.1 mg/l of pristine polymer microspheres 1–5 μm diameter) caused parental mortality (10–100%), and significantly (p ≤ 0.05) decreased growth, reproduction, and population growth rate leading to the extinction of the microplastics-exposed model population in the F1 generation.
Females descending from those exposed to microplastics in F0 and exposed to clean medium presented some
recovery but up to the F3 generation they still had significantly (p ≤ 0.05) reduced growth, reproduction, and population growth rate.
Overall, these results indicate that D. magna recovery from chronic exposure to microplastics may take several generations, and that the continuous exposure over generations to microplastics may cause population extinction. These findings have implications to aquatic ecosystem functioning and services, and raise concern on the long-term animal and human exposure to microplastics through diverse routes.

https://www.sciencedirect.com/science/article/pii/S0048969718308088/pdfft?md5=6fa0f832e5a8190864431ace24bb80e0&pid=1-s2.0-S0048969718308088-main.pdf

https://drive.google.com/open?id=11576m0z5uvxKc859MUCll_qFritxwJBx
https://doi.org/10.1016/j.scitotenv.2018.03.054.(https://www.sciencedirect.com/science/article/pii/S0048969718308088)

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