Positive Health Online

Abstract

FINGER and COLLEAGUES, 1. Institute for Sustainability & Innovation, College of Engineering and Science, Victoria University, PO Box 14428, Melbourne, Victoria 8001, Australia. Annett.Finger@live.vu.edu.au ; 2. Institute for Marine and Antarctic Studies, 20 Castray Esplanade, Battery Point, Tasmania 7004, Australia; 3. Research Department, Phillip Island Nature Parks, PO Box 97, Cowes, Victoria 3922, Australia; 4. School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia; 5. Institute for Sustainability & Innovation, College of Engineering and Science, Victoria University, PO Box 14428, Melbourne, Victoria 8001, Australia; 6. RMIT University, School of Science, GPO Box 2476, Melbourne, Victoria, Australia studied and determined the concentration of heavy metals – arsenic, cadmium, mercury, lead and selenium – in fish species in St Kilda, Melbourne, Australia.

Background

Piscivorous species like the Little Penguin (Eudyptula minor) are particularly at risk of being negatively impacted by pollution due to their heightened exposure through aquatic food chains.

Methodology

Therefore, determining the concentration of heavy metals in the fish prey of seabirds is an essential component of assessing such risk. In this study, we report on arsenic, cadmium, mercury, lead and selenium concentrations in three fish species, which are known to comprise a substantial part of the diet of Little Penguins at the urban colony of St Kilda, Melbourne, Australia.

Results

Metal concentrations in the fish sampled were generally within the expected limits, however, arsenic and mercury were higher than reported elsewhere. Anchovy (Engraulis australis) and sandy sprat (Hyperlophus vittatus) contained higher Hg concentrations than pilchard (Sardinops sagax), while sandy sprat and pilchard contained more selenium. We present these findings together with metal concentrations in Little Penguin blood and faeces, sampled within weeks of the fish collection. Mercury concentrations were highest in the blood, while faeces and fish prey species contained similar concentrations of arsenic and lead, suggesting faeces as a primary route of detoxification for these elements. We also investigated paired blood - faecal samples and found a correlation for selenium only.

Conclusion

Preliminary data from stable isotope ratios in penguin blood indicate that changes in penguin blood mercury concentrations cannot be explained by trophic changes in their diet alone, suggesting a variation of bioavailable Hg within this semi-enclosed bay.

References

Finger A1, Lavers JL2, Dann P3, Kowalczyk ND4, Scarpaci C5, Nugegoda D6, Orbell JD5. Metals and metalloids in Little Penguin (Eudyptula minor) prey, blood and faeces. Environ Pollut. 223:567-574. doi: 10.1016/j.envpol.2017.01.059. Epub 2017 Jan 31. Apr  2017.