Potential Master projects offered in collaboration with NIVA
The following projects will be offered (details found below):
Toxicological effects of persistent pollutants in an avian in vitro bioassay............................... 2
Assessment of thyroxin mimics in the environment .................................................................. 2
DNA-damage and repair in liver cells from fish ........................................................................ 3
Determination of biomarker expression in earthworms earthworms or fish after exposure to
nanoparticles............................................................................................................................... 3
Determination of biomarker expression in earthworms or fish after exposure to ionizing
radiation. ..................................................................................................................................... 4
Combined toxicity of compounds to algae and fish ................................................................... 4
Microarray-assisted assessment of the toxicity of oil and oil components to the common
mussel. ...................................................................................... Error! Bookmark not defined.
Microarray-assisted assessment of the toxicity of oil and oil components to the marine
zooplankton Calanus Finmarchicus. .......................................................................................... 5
Chemical modulation of hormone transport in Arctic birds ...................................................... 5
Characterisation of road run-off by a suite of in vitro bioassays ............................................... 6
Toxicological effects of persistent pollutants in an avian in
vitro bioassay
Background: persistent pollutants are deposited worldwide through long range atmospheric
transport and accumulate in Artic species including birds and mammals. An in vitro bioassay
based on chicken hepatoma cells will be developed in order to study the effects of persistent
pollutants on birds and understand the mechanism of toxicity of single chemicals and complex
mixtures.
Objective: one to two master studies will be offered to establish and use a chicken hepatoma
cell line to determine the toxicity of single chemicals and complex mixtures relevant for
temporal and Arctic exposure scenarios. The toxicity endpoints that will be studied by one
student include acute toxicity, biotransformation (phase-I and phase-II biotranformation), and
endocrine disruption (estrogenicity). Another student will measure the cellular gene
expression by a combination of Microarray and rtPCR. The data generated will be used to
understand the mechanisms of toxicity of typical pollutants encountered by birds
Workplace: The work will be conducted at the Norwegian Institute for Water Research
(NIVA) in collaboration with scientists at the UMB.
Contact: Dr. Knut-Erik Tollefsen (e-mail: ket@niva.no, phone: 92218466).
Assessment of thyroxin mimics in the environment
Background: Thyroxin mimics have rapidly emerged as a new group of endocrine disruptors
potentially affecting the growth and development of vertebrates. The endocrine disrupting
activity of these exogenous compounds is believed to be caused by direct interaction with and
modulation of intracellular thyroid receptors (TRs) and through modulation of the production,
transport and biotransformation of the thyroid hormones L-thyroxin (T4) and tri-iodothyronin
(T3) or their precursor hormones.
Objective: A master study will be offered to study the presence of thyroid hormone disrupters
in various environmental compartments such as sediments and surface water from both
freshwater and marine habitats using a thyroid hormone sensitive cell culture and inhibition of
T3 and T4 to their plasma hormone transport proteins. The work will consist of some
optimization of methods for use on complex environmental samples followed by screening
existing samples for endocrine disrupting activity.
Workplace: The work will be conducted at the Norwegian Institute for Water Research
(NIVA) and IPM (UMB).
Contact: Dr. Knut-Erik Tollefsen (e-mail: ket@niva.no)
DNA-damage and repair in liver cells from fish
Background: a high number of chemicals, UV light and ionizing radiation are known to
cause DNA damage and act as potential precursors for cancer development. Damage to DNA
is the first sign of damage and may thus be used as a biomarker for more adverse effects in
vitro as well as in vivo.
Objective: optimize a rapid high-throughput method for DNA damage and repair assessment
in fish in vitro and in vivo experimental models. Compare with established methods such as
the COMET method after exposure to chemicals, UV and ionizing radiation.
Workplace: The experimental work and some of the practical work will be conducted at
NIVA and analysis of COMET will be performed in collaboration with Dr. Gunnar Brunborg
at the National Institute for Public Health.
.
Contakt: Knut-Erik Tollefsen (ket@niva.no, tlf: 92218466)
Determination of biomarker expression in earthworms or
fish after exposure to nanoparticles.
Background: nanoparticles are introduced to the environment and may potentially cause
effects to terrestrial and aquatic species such as earthworms and fish. These effects may cause
induction/suppression of biomarkers for toxicity.
Objective: A master study is offered to optimize, evaluate and determine how exposure to
nanoparticles affect gene expression in earthworms or fish by a combination of microarray
and quantitative rtPCR analysis to determine gene expression.
Workplace: The experimental work will be conducted at UMB and analysis performed at
NIVA. The Master student will collaborate with a post doc. and possible also another master
student at UMB in optimizing the methodology.
Contacts: Dr. Knut-Erik Tollefsen (e-mail: ket@niva.no) and Professor. Debroah Oughton
(e-mail: Deborah.oughton@umb.no).
Determination of biomarker expression in earthworms or
fish after exposure to ionizing radiation.
Background: Ionizing radiation may affect various terrestrial organisms and potentially
cause adverse effects in terrestrial and aquatic species such as earthworms and fish.
Expression of biomarkers for toxicity may provide predictive assessment of effects and
identify the mechanisms of toxic action.
Objective: A master study is offered to optimize, evaluate and determine the gene expression
by microarrays and quantitative rtPCR analysis in earthworms or fish after exposure to
ionizing radiation.
Workplace: The experimental work will be conducted at UMB and analysis performed at
NIVA. The Master student will collaborate with a post doc. and possible also another master
student at UMB in optimizing the methodology.
Contacts: Dr. Knut-Erik Tollefsen (e-mail: ket@niva.no) and Professor. Debroah Oughton
(e-mail: Deborah.oughton@umb.no).
Combined toxicity of compounds to algae and fish
Background: environmental pollutants occur as complex mixtures in the environment and
determination of the role of combined toxicity of complex mixtures are rarely acknowledged
and to even lesser degree described.
Objective: study combined toxicity of organic compounds in one or more of the following
experimental systems: marine or freshwater algae, fish liver cell culture and/or whole fish.
The choice of methods will depend on test system chosen and the experience of the potential
candidate. Some potential endpoints may be chronic growth inhibition (algae), as well as
estrogenicity, EROD induction and gene expression by rtPCR and/or microarrays (fish in
vitro and in vivo assays).
Workplace: The experimental work will be conducted at NIVA and UMB and analysis
performed at NIVA. The master student will collaborate with a Ph.D. working at NIVA to
perform the work.
Contacts: Dr. Knut-Erik Tollefsen (e-mail: ket@niva.no).
Microarray-assisted assessment of the toxicity of oil and
oil components to the marine zooplankton Calanus
Finmarchicus.
Background: Calanus Finmarchicus is a marine copepod inhabiting temporal and arctic
waters and the species is frequently used to determine the effect of oil and oil-related
compounds to the North Sea. Development and evaluation of molecular tools for assessing the
(gene) expression of biomarkers for toxicity in this species may provide predictive tools for
determining potential effects of oil exploration in the North Sea and Barents Sea.
Objective: study pure chemicals and complex samples ability to induce induction/suppress
biomarker (gene) expression by a combination of microarrays and quantitative rtPCR
analysis.
Workplace: The experiments will be conducted at Sintef, Materials and Chemistry
(Trondheim) and analysis to be performed at NIVA.
Contact: Dr. Knut-Erik Tollefsen (e-mail: ket@niva.no, phone: 92218466).
Chemical modulation of hormone transport in Arctic birds
Background: persistent pollutants are deposited worldwide through long range atmospheric
transport and accumulate in Artic species including birds and mammals. Some of these
chemicals are well known endocrine disruptors. Recent studies suggest that interference with
the hormone transport of steroids and thyroid hormones may cause endocrine disruption and
studies that target these hormone disruptors in Arctic birds is highly warranted.
Objective: a master study will be offered to study the interaction and modulation of hormone
transport and transport proteins in arctic species such as the Glacous gull, black-legged
kittiwakes, and Northern fulmar. The studies will include characterisation of the hormone
binding sites, competitive studies with various persistent pollutants, measurement of
circulating hormone binding proteins and their free fraction in plasma. The data generated
will be used to unravel the mechanisms of toxicity of typical Arctic pollutants encountered by
Arctic birds
Workplace: The work will be conducted at the Norwegian Institute for Water Research
(NIVA) in collaboration with scientists at UMB and the Norwegian Polar Institute. It is
anticipated that the practical work also will include a field trip to Svalbard to assist in
biological sampling.
Contact: Dr. Knut-Erik Tollefsen (e-mail: ket@niva.no, phone: 92218466).
Characterisation of road run-off by a suite of in vitro
bioassays
Background: Road run-off after snow melting or tunnel washes is potential contributors to
pollution contribution to the terrestrial and aquatic environment. The run-off are highly
complex mixtures of ionorganic and organic compounds that may exhibit a wide variety of
different effects.
Objective: a master study will be offered to characterise the toxicity of the organic pollutants
present in road run-off after performing tunnel washes and melting of contaminated snow
from heavy trafficked raods. The toxicity characterisation will be conducted by a battery of in
vitro bioassays including some of the following: assessment of acute toxicity in a fish cells,
assessment of sub-lethal effects in the yeast estrogen screen (estrogens and anti-estrogen), the
yeast androgen screen (androgens and anti-androgens), arylhydrocarbon receptor (AhR)
active compounds, and thyroxin-disrupting compounds (T-screen and TTR competitive
binding assay).
Workplace: The work will be conducted at the Norwegian Institute for Water Research
(NIVA) in collaboration with scientists at UMB and statens Vegvesen. It is anticipated that
the practical work also will a field/sampling trip as well as detailed laboratory work at the
NIVA ecotoxicological laboratory.
Contact: Dr. Knut-Erik Tollefsen (e-mail: ket@niva.no, phone: 92218466).