B.Sc. (Honours), Trinity College Dublin
M.Sc., University College Dublin
Arafura Timor Research Facility
23 Ellengowan Drive,
Brinkin NT 0810
Telephone: (08)8920 9250
The Effects of Endocrine Disrupting Chemicals On Molluscs in Darwin Harbour.
Supervisors: Prof. Karen Gibb (CDU), Prof. David Parry (AIMS), Sue Codi King (AIMS), Dr Keith McGuinness.
An increase in the number of cases of developmental and reproductive impairment reported in overseas wildlife populations has sparked intense research into the potential for chemical contaminants to disrupt normal hormonal (endocrine) function in animals (Hogan et al. 2005). Along with the nervous system, the endocrine system is one of two communication systems that regulate all responses and functions of the body. Chemicals that interfere with the normal functioning of the endocrine system are termed endocrine disrupting chemicals (EDCs) (Ying and Kookana 2002).
EDCs are of high environmental relevance since many essential physiological processes which impact on an organism's health, such as growth and development, stress response, and ultimately reproduction and population developement are controlled by hormones (Scholz and Mayer, 2008). The risks of EDCs to Australian populations and ecosystems are currently unknown because there has not yet been sufficient research, with Australia lagging behind Europe and North America in endocrine disruption research (Ying and Kookana 2002).
This project will focus on measuring the bioaccumulation of endocrine disrupting chemicals (EDCs) in molluscs and associated effects on physiological and biochemical functioning. In order to do this two species of aquatic mollusc with contrasting feeding strategies (the benthic feeder Telescopium telescopium and the filter feeding Indo-west Pacific rock oyster Saccostrea spp.) will be sampled from impacted (sewage outfall sites) and non-impacted sites in the Darwin Harbour region. The tissues of impacted and non-impacted organisms will be analysed in order to:
- Identify and quantify a number of proven endocrine disrupting chemicals.
- Assess the prevalence of a suite of histopathological markers as indicators of effects.
- Identify proteins that are differentially expressed in tissue with elevated EDCs compared to controls that could be used in future to identify biomarkers of EDC exposure.
The analysis that will be carried out during this project is divided into different stages which represent increasing levels of complexity of the issue of EDCs in the aquatic enviornment. Step 1 is establishing at what level EDCs are present in the environment; step 2 is establishing if and at what levels EDCs are bioaccumulating in mollusc tissue; step 3 is establishing if the presence of EDCs in tissue results in histopathological effects and; step 4 identifying differentially expressed proteins in exposed shellfish that could be used in future to identify biomarkers of EDC exposure.
Hogan A., Peck M., Van Dam R. & Kennett R. (2005) Screening for endocrine disrupting activity in surface waters of Kakadu National Park. Ecological Management & Restoration 6, 219-21.
Scholz S. and Mayer I. (2008) Molecular biomarkers of endocrine disruption in smal model fish. Molecular and Cellular Endocrinology 293: 57-70.
Ying G.-G. & Kookana R. (2002) Endocrine Disruption: An Australian Persepective. Water 42-5.