Evaluating direct and indirect effects of nanoplastic particles on Daphnia magna under environmental conditions using artificial wetland mesocosms
(2021) BIOM02 20211Degree Projects in Biology
- Abstract
- Plastics pollution is increasing every year in aquatic ecosystems and with it, an ever-increasing number of micro- and nano-sized plastic particles. It has been shown that these particles find their way into the food-chain after being consumed by organisms at lower trophic levels, such as the zooplankter Daphnia magna. Previous studies have shown negative effects on the reproduction, development, and survival of D. magna. However, most studies have only evaluated the effects under laboratory conditions and have not considered how the toxicity may vary under natural conditions. For this, a mesocosm approach was used to evaluate the effects of nanoplastic particles (NP) on the behavioral responses and population dynamics of D. magna, as well... (More)
- Plastics pollution is increasing every year in aquatic ecosystems and with it, an ever-increasing number of micro- and nano-sized plastic particles. It has been shown that these particles find their way into the food-chain after being consumed by organisms at lower trophic levels, such as the zooplankter Daphnia magna. Previous studies have shown negative effects on the reproduction, development, and survival of D. magna. However, most studies have only evaluated the effects under laboratory conditions and have not considered how the toxicity may vary under natural conditions. For this, a mesocosm approach was used to evaluate the effects of nanoplastic particles (NP) on the behavioral responses and population dynamics of D. magna, as well as the uptake of particles and possible indirect effects through the food source (phytoplankton algae). D. magna individuals were exposed to negatively charged polysterene (PS) nanoparticles of about 80 nm size with a core made of gold at an approximate concentration of 0.2 mg/l for a chronic exposure of 10 weeks under environmental conditions with a mesocosm approach. The gold core in the particles allowed the determination of the uptake and fate of these using “inductively coupled plasma mass spectrometry” (ICP-MS) to measure the gold concentration. The swimming behavior was evaluated as the immediate response to ultraviolet (UV) radiation exposure. The population dynamics and algae biomass were followed every week throughout the exposure. No direct effects were found on behavior or population dynamics. Nonetheless, an uptake of nanoparticles by D. magna individuals was observed and significant effects of the NP treatments on algae biomass were found, that could potentially lead to a possible indirect effect on D. magna in the long run. The fluctuations in the concentration of particles and their interaction with the ecosystem might have played an important role in the toxicity levels observed. This study shows a glimpse of what could be the effect of nanoplastic particles in wetland ecosystems. (Less)
- Popular Abstract
- Effects of nanoplastics in a Zooplankton species (Daphnia magna) under environmental conditions
Plastic production is increasing every year and with it the number of plastic debris found in the aquatic ecosystem. These debris can be of different sizes including micro- and nano-sized particles. The latter have been found to be more toxic than bigger particles and this is because their small size allows them to pass biological barriers like the cellular membrane. In the ecosystem, the nanoplastic particles can be ingested by filter-feeder organisms like Daphnia magna that is a direct link between primary producers and higher trophic levels in freshwater ecosystems. Thus, nanoplastic particles could find their way into the food-chain and... (More) - Effects of nanoplastics in a Zooplankton species (Daphnia magna) under environmental conditions
Plastic production is increasing every year and with it the number of plastic debris found in the aquatic ecosystem. These debris can be of different sizes including micro- and nano-sized particles. The latter have been found to be more toxic than bigger particles and this is because their small size allows them to pass biological barriers like the cellular membrane. In the ecosystem, the nanoplastic particles can be ingested by filter-feeder organisms like Daphnia magna that is a direct link between primary producers and higher trophic levels in freshwater ecosystems. Thus, nanoplastic particles could find their way into the food-chain and affect the ecosystem. Furthermore, the behavior of these particles in the environment is not known deeply, and it will depend on their type, their surface properties, their size, among other. So, it is of great importance to study how nanoplastics will behave under natural conditions and how these will affect the aquatic biota.
A good approach for studying this is by evaluating natural responses of organisms like D. magna exposed to nanoplastic particles under realistic conditions or the more realistically possible under a control environment. For this, mesocosms were built as “mini-wetlands ecosystems” in individual aquariums, with all the elements that can be present in a natural wetland. There, the organisms were exposed to nanoplastics for 10 weeks and during that time different aspects were evaluated, such as: the changes in population size (population dynamics), the swimming behavior of individuals in response to a natural stressor (ultraviolet radiation (UV)), the uptake of particles by the organisms and possible indirect effects of in the food source (effects on the microalgae populations). No effects were found after being exposed to nanoplastics in the population dynamics or in the swimming behavior of the organisms. However, in the latter there was seen to be a possible trend where the exposed individuals swam shallower and were less protected from the UV radiation. Also, the particles were found to be taken up by the organisms and the food source (microalgae) was significantly affected at the last week of exposure to nanoplastics.
The toxicity of pollutants like nanoparticles seems to depend in the concentration and/or duration of the exposure, in the exposure conditions (laboratory or natural), and in the different aspects of the particles. Mostly, under natural conditions these particles may interact with other elements or particles which could increase or decrease its toxicity towards the organisms. Which is the case for this study, where the particles were most likely interacting in a natural environment with other elements, which has seen to possibly decrease their toxicity. Additionally, the exposure concentrations were constantly changing because to simulate a real wetland ecosystem, the system had a constant flux of water that could flush the particles away. Thus, this probably allowed the individuals to recover from the particles’ toxicity. In conclusion, no significant effects of nanoplastics in the life cycle of D. magna were found but it is possible that these two factors might have played an important role in the toxicity levels observed. This shows a glimpse of what happens with nanoplastics in natural wetland ecosystems.
Master’s Degree Project in Biology: Aquatic Ecology, 30 credits, 2021
Department of Biology, Lund University
Advisor: Mikael Ekvall
Aquatic Ecology division (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9069181
- author
- Rivas, Pierina Isabella
- supervisor
- organization
- course
- BIOM02 20211
- year
- 2021
- type
- H2 - Master's Degree (Two Years)
- subject
- language
- English
- id
- 9069181
- date added to LUP
- 2021-12-16 13:25:57
- date last changed
- 2021-12-16 13:25:57
@misc{9069181,
abstract = {{Plastics pollution is increasing every year in aquatic ecosystems and with it, an ever-increasing number of micro- and nano-sized plastic particles. It has been shown that these particles find their way into the food-chain after being consumed by organisms at lower trophic levels, such as the zooplankter Daphnia magna. Previous studies have shown negative effects on the reproduction, development, and survival of D. magna. However, most studies have only evaluated the effects under laboratory conditions and have not considered how the toxicity may vary under natural conditions. For this, a mesocosm approach was used to evaluate the effects of nanoplastic particles (NP) on the behavioral responses and population dynamics of D. magna, as well as the uptake of particles and possible indirect effects through the food source (phytoplankton algae). D. magna individuals were exposed to negatively charged polysterene (PS) nanoparticles of about 80 nm size with a core made of gold at an approximate concentration of 0.2 mg/l for a chronic exposure of 10 weeks under environmental conditions with a mesocosm approach. The gold core in the particles allowed the determination of the uptake and fate of these using “inductively coupled plasma mass spectrometry” (ICP-MS) to measure the gold concentration. The swimming behavior was evaluated as the immediate response to ultraviolet (UV) radiation exposure. The population dynamics and algae biomass were followed every week throughout the exposure. No direct effects were found on behavior or population dynamics. Nonetheless, an uptake of nanoparticles by D. magna individuals was observed and significant effects of the NP treatments on algae biomass were found, that could potentially lead to a possible indirect effect on D. magna in the long run. The fluctuations in the concentration of particles and their interaction with the ecosystem might have played an important role in the toxicity levels observed. This study shows a glimpse of what could be the effect of nanoplastic particles in wetland ecosystems.}},
author = {{Rivas, Pierina Isabella}},
language = {{eng}},
note = {{Student Paper}},
title = {{Evaluating direct and indirect effects of nanoplastic particles on Daphnia magna under environmental conditions using artificial wetland mesocosms}},
year = {{2021}},
}