Oral Presentation Society of Environmental Toxicology and Chemistry Australasia 2021

Trace element concentrations in liver and muscle tissue of white sharks (Carcharodon carcharias) from the east coast of Australia (#52)

Julia L Smith 1 , Victor Peddemors 2 , Jason van de Merwe 1 , William Bennett 3 , Frederic Leusch 1 , Liesbeth Weijs 1
  1. Australian Rivers Institute, School of Environment and Science, Griffith University, Gold Coast campus, Southport, Queensland, Australia
  2. NSW DPI Fisheries, Sydney Institute of Marine Science, Mosman, New South Wales, Australia
  3. Coastal and Marine Research Centre, School of Environment and Science, Griffith University, Gold Coast campus, Southport, Queensland, Australia

Sharks play a crucial predatory role in aquatic ecosystems, but many species and populations are highly vulnerable to a wide range of anthropogenic stressors. While some of the largest threats include fishing mortality and climate change, sharks may also be affected by pollution. White sharks (Carcharodon carcharias) typically accumulate considerable amounts of pollutants in their tissues due to their apex position in the food web, long life span, large size and lipid-rich livers, potentially causing risks to individual, population, and/or species health. Although some trace elements have been monitored in shark species across the world, there is a lack of research on contaminant concentrations in sharks from Australia. The objectives of this study were to assess baseline levels of both essential and non-essential elements in white shark tissues, compare tissue concentrations to those reported for other white shark populations, and to determine if tissue concentrations vary due to size and sex. Paired liver and muscle samples from female (n = 37) and male (n = 30) white sharks with total lengths between 1.62 m to 4.65 m were collected from 2013 to 2020 in collaboration with the New South Wales Shark Meshing (Bather Protection) Program (NSW SMP) and the Queensland Shark Control Program (QSCP). Several elements, including arsenic, cadmium, chromium, cobalt, copper, lead, manganese, mercury, molybdenum, nickel, selenium, vanadium, and zinc, were measured in tissues using microwave-assisted dissolution followed by inductively coupled plasma – mass spectrometry (ICP-MS). Baseline concentrations and trends in this study will not only contribute to the future biomonitoring of these elements in white sharks but will also provide a foundation for future research assessing the effects of trace elements on their health. Since sharks are exposed to other anthropogenic stressors, understanding the health of these species is important for future conservation and management.