Haynes, 2001:

• "Document the concentrations of trace metals and pesticides in intertidal and subtidal sediments and/or seagrasses along the Great Barrier Reef coasts;
• Investigate the toxicity of widely distributed pesticides to common seagrass species;
• Document the concentrations of pesticides in carcases of dugong stranded along the Queensland coast; and
• Carry out a risk evaluation of pollutants to the Great Barrier reef environment in general and to local dugong in particular."

"Agriculture, public health and industrial activities around the world have contributed to the widespread contamination of global ecosystems with organochlorine compounds and heavy metals (Fowler 1990; Tatsukawa et al. 1990).  Both of these types of pollutants are conservative and are essentially permanent additions to the environment (Clark 1992)."

AND

"Particulate metals in suspension and in bottom sediments are not generally directly available to aquatic organisms. (The exception to this are sediment bound metals which can be accumulated following solubilisation in the acidic juices of a sediment-feeders gut (Waldichuk 1985)).  Once solubilised in the water column, metals may be accumulated by marine invertebrates from solution via passive uptake across permeable surfaces such as gills and the digestive tract (Rainbow 1990).  Metals may also be accumulated from food."

AND

"Denton and co-workers reported metal concentrations in muscle, liver, kidney, lung and brain and in the blood of 48 dugongs collected from Torres Strait and Townsville between 1974 and 1978 (Denton et al. 1980; Denton 1981; Denton and Breck 1981).  These studies detected unusually high concentrations of Fe (iron) and Zn (zinc) in liver and high concentrations of Cd (cadmium) in kidney.  Concentrations of Cu (copper), Cd, Co (cobalt) and Ag (silver) were also elevated in the liver compared with concentrations in other species of marine mammals.  Concentrations of Fe, Zn, Cd and Co in the liver and Cd in the kidney were positively correlated with age."

AND

"A range of pollutants were detected in dugong tissues sampled along the Queensland coast between 1996 and 2000.  Liver concentrations of metals were generally similar to, or lower than those reported previously in dugong collected along the northern Australian coast and in Torres Strait (Deton et al. 1980; Denton and Breck 1981; Marsh 1989; Parry and Munksgaard 1992; Parry and Munksgaard 1993; Dight and Gladstone 1993; Gladstone 1996).  The general trend of higher average metal concentrations in mature dugong compared with younger animals found in these samples is typical of metal accumulation patterns present in marine mammals, and is associated with length of contaminant exposure (Aguiler et al. 1998; O’Shea 1999; O’Shea et al. 1999)."

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Citation and/or URL

Haynes, D. 2001, Pesticides and heavy metal concentrations: impacts on Great Barrier Reef sediments, seagrass and dugong (Dugong dugon), Ph.D thesis, University of Queensland, Brisbane, Australia.

Spatial Coverage

Great Barrier Reef

Temporal Coverage

2001

Update Frequency

Other Information

 None