Faculty of Science, Engineering and Built Environment
School of Life and Environmental Sciences
The proximate and ultimate effects of endocrine disruption in birds
Participants: Dr Katherine L Buchanan (PI), Prof Lee Astheimer
Aims and background: Endocrine disrupting chemicals (EDCs) are natural and synthetic hormone mimics which bind with hormone receptors, causing either upregulation or down regulation of transcription. They are of significant public concern. Indeed, the Intergovernmental Forum on Chemical Safety (Ottawa, 1997) obliges government members to promote research into this area. EDCs have been linked to morphological and behavioural changes in a range of aquatic organisms including reptiles, amphibians, birds and most dramatically in fish. As a result, this is a priority funding area for research funding councils and a highly active area of scientific research (9,000+ ISI publications). KLB has recently demonstrated that birds and bats are at risk from a range of known EDCs when they forage at sewage treatment works, due to bioaccumulation of EDCs within invertebrate prey (Markman et al 2007, Park et al 2009). The chemicals which have been identified in invertebrates living in or emerging from the sewage treatment beds include 17β-estradiol (natural estrogen), dibutylphthalate, dioctylphthalate, and bisphenol-A (plasticisers) and 17α-ethinylestradiol (synthetic estrogen from pharmaceutical contraception). Experimental administration of these chemicals at ecologically relevant dose levels, and in combinations that birds encounter them, shows that exposed birds have reduced immunocompetence, but enhanced song complexity due to hypermasculinisation within the brain (Markman et al 2008). These chemicals may well have undocumented population level effects.
Scientific significance and innovation: Globally, there has been relatively little work on the exposure of terrestrial animals to EDCs. This project seeks to quantify the exposure levels of Australian birds for the first time. The student will examine bird foraging behaviour at Werribee Sewage Treatment Works (STW) to quantify possible routes of transfer. The student will build a collaboration with Melbourne Water, which will ensure a future ARC Linkage application. Samples will be analysed in collaboration with Prof Neil Barnett and Xavier Conlan at Deakin University to quantify the levels of known endocrine-disrupting chemicals. Focal observations of marked birds will be used to quantify intake rates while foraging and exposure levels. In addition, the student will perform the first examination of transgenerational effects of exposure to endocrine disrupters in birds. EDCs are hypothesised to alter levels of DNA methylation causing epigenetic effects, but this remains uninvestigated in birds.
Potential national benefit and strategic alignment with the aims of the CIE: This project is aligned with the aims of the CIE in that it addresses the impact of anthropogenic chemicals with wild birds and the consequent evolutionary changes. This area is of research interest to water companies attempting to minimise the environmental impact of sewage processing. Potential ARC Linkage partners (Melbourne Water, EPA, Barwon Water) have been identified and they have expressed considerable interest in the project. Prof Lee Astheimer has valuable and relevant expertise in the area of endocrine disruption.
Markman, S., I. A. Guschina, S. Barnsley, K. L. Buchanan, D. Pascoe, C. T. Müller (2007) Chemosphere 70, 119-125.Markman, S., Leitner, S., Catchpole, C.K., S. Barnsley, D. Pascoe, C. T. Müller, and K. L. Buchanan (2008) Pollutants PLoS One 3(2): e1674. Park, K.J., C.T. Müller, S. Markman, O. Swinscow-Hall, D. Pascoe and K.L. Buchanan (2009) Chemosphere
