Skip to main content

LUP Student Papers

LUND UNIVERSITY LIBRARIES

Effects of the selective serotonin reuptake inhibitor (SSRI) sertraline on life history parameters and population growth rate of Daphnia magna

Röös, Ingrid (2013) BION14 20122
Degree Projects in Biology
Abstract
Abstract

This study tested the effect of environmental concentrations of the selective serotonin reuptake inhibitor (SSRI) sertraline on the life history of Daphnia magna and how individual-level responses could predict effects on population growth rate. Individual-level responses related to reproduction, growth and feeding were quantified in a 39-day bioassay and used in a life-table matrix. Although no significant effect of sertraline in the concentration range of 0.012-120 µg/l on the life history parameters was found, there was a 15-60 % decrease of juvenile grazing in sertraline treatments. There was also a 20-64 % decrease of population growth rate of D. magna affected by sertraline. The results indicate that there is a possible... (More)
Abstract

This study tested the effect of environmental concentrations of the selective serotonin reuptake inhibitor (SSRI) sertraline on the life history of Daphnia magna and how individual-level responses could predict effects on population growth rate. Individual-level responses related to reproduction, growth and feeding were quantified in a 39-day bioassay and used in a life-table matrix. Although no significant effect of sertraline in the concentration range of 0.012-120 µg/l on the life history parameters was found, there was a 15-60 % decrease of juvenile grazing in sertraline treatments. There was also a 20-64 % decrease of population growth rate of D. magna affected by sertraline. The results indicate that there is a possible effect of chronic exposure of sertraline on life history and population growth rate of D. magna populations.

Popular science summary:

Do anti-depressants affect life-history of water fleas?

The presence of pharmaceuticals in aquatic environments has become a growing environmental concern and since pharmaceuticals are designed to have a biological effect on humans they are likely to affect other organisms as well. Sertraline is a common antidepressant that affects levels of the neurotransmitter serotonin in the body. Serotonin is found in many different types of animals and sertraline could therefore affect all these animals as well.

Water-fleas are small crustaceans and the species used in this study, Daphnia magna, is often used to test toxicity of different compounds. Effects of sertraline, and of the similar compound fluoxetine, on the reproduction of D. magna have been found but these results have not been connected to changes in population growth rate (λ).

In this study, D. magna were exposed to five concentrations of sertraline (120, 12, 1.2, 0.12 and 0.012 µg/l). Survival, time to first reproduction, number of offspring and broods produced, size of offspring, juvenile feeding and adult size were investigated. The reproduction and survival results were then used in a simple life-table model to predict changes in λ.
Results
There was no significant effect of sertraline on any of the reproduction parameters, survival or adult size. However, there was a decrease in juvenile feeding when the daphnids were exposed to sertraline. There was also a 20% decrease in λ.

The decreased juvenile feeding could affect growth rate and reproduction, even though no such effects were found in this study. That could be because only adult size were measured. Also, the reason why no effect on reproduction was seen could be because the daphnids that I used did not reproduce as normal. My daphnids had an average brood size of 1.8, which is very low for a species that can get 100 offspring/brood.

A 20% decrease in λ could have a large effect on the population but it depends on the original value of λ. A population growth rate of one indicates that the population is stable. A value above one indicates that the population is increasing, below one the population is heading towards extinction. If λ is close to one a 20% decrease could be the difference between an increasing or decreasing population. However, in this study, λ was well above one. Therefore, the effect of the decrease would not be as large.

If there is an effect of sertraline and other SSRI’s on λ of D. magna it could affect the balance of species in a freshwater community, potentially resulting in a larger impact on the entire ecosystem.

Handledare: Olof Berglund and Melanie Hedgespeth
Master´s Degree project 45 credits in Ecotoxocology 2013
Department of Biology., Lund University (Less)
Please use this url to cite or link to this publication:
author
Röös, Ingrid
supervisor
organization
course
BION14 20122
year
type
H2 - Master's Degree (Two Years)
subject
language
English
id
3810317
date added to LUP
2013-06-11 13:45:59
date last changed
2013-06-11 13:45:59
@misc{3810317,
  abstract     = {Abstract

This study tested the effect of environmental concentrations of the selective serotonin reuptake inhibitor (SSRI) sertraline on the life history of Daphnia magna and how individual-level responses could predict effects on population growth rate. Individual-level responses related to reproduction, growth and feeding were quantified in a 39-day bioassay and used in a life-table matrix. Although no significant effect of sertraline in the concentration range of 0.012-120 µg/l on the life history parameters was found, there was a 15-60 % decrease of juvenile grazing in sertraline treatments. There was also a 20-64 % decrease of population growth rate of D. magna affected by sertraline. The results indicate that there is a possible effect of chronic exposure of sertraline on life history and population growth rate of D. magna populations. 

Popular science summary:

Do anti-depressants affect life-history of water fleas?

The presence of pharmaceuticals in aquatic environments has become a growing environmental concern and since pharmaceuticals are designed to have a biological effect on humans they are likely to affect other organisms as well. Sertraline is a common antidepressant that affects levels of the neurotransmitter serotonin in the body. Serotonin is found in many different types of animals and sertraline could therefore affect all these animals as well.

Water-fleas are small crustaceans and the species used in this study, Daphnia magna, is often used to test toxicity of different compounds. Effects of sertraline, and of the similar compound fluoxetine, on the reproduction of D. magna have been found but these results have not been connected to changes in population growth rate (λ). 

In this study, D. magna were exposed to five concentrations of sertraline (120, 12, 1.2, 0.12 and 0.012 µg/l). Survival, time to first reproduction, number of offspring and broods produced, size of offspring, juvenile feeding and adult size were investigated. The reproduction and survival results were then used in a simple life-table model to predict changes in λ.
Results
There was no significant effect of sertraline on any of the reproduction parameters, survival or adult size. However, there was a decrease in juvenile feeding when the daphnids were exposed to sertraline. There was also a 20% decrease in λ. 

The decreased juvenile feeding could affect growth rate and reproduction, even though no such effects were found in this study. That could be because only adult size were measured. Also, the reason why no effect on reproduction was seen could be because the daphnids that I used did not reproduce as normal. My daphnids had an average brood size of 1.8, which is very low for a species that can get 100 offspring/brood.

A 20% decrease in λ could have a large effect on the population but it depends on the original value of λ. A population growth rate of one indicates that the population is stable. A value above one indicates that the population is increasing, below one the population is heading towards extinction. If λ is close to one a 20% decrease could be the difference between an increasing or decreasing population. However, in this study, λ was well above one. Therefore, the effect of the decrease would not be as large.

If there is an effect of sertraline and other SSRI’s on λ of D. magna it could affect the balance of species in a freshwater community, potentially resulting in a larger impact on the entire ecosystem.

Handledare: Olof Berglund and Melanie Hedgespeth
Master´s Degree project 45 credits in Ecotoxocology 2013
Department of Biology., Lund University},
  author       = {Röös, Ingrid},
  language     = {eng},
  note         = {Student Paper},
  title        = {Effects of the selective serotonin reuptake inhibitor (SSRI) sertraline on life history parameters and population growth rate of Daphnia magna},
  year         = {2013},
}