Gladstone Fish Health Investigation 2011 - 2012 - Western Basin ...

Department of Science, Information Technology, Innovation and the Arts5. Are the concentrationsof contaminants inn crab andfish tissuefrom Gladsttone similar to thosee from otherQueensland estuarine and near-coastal locations?Measured concentration of contaminants in tissues collected from aquatic organisms can be usedto assess overall environmental exposure too contaminants over time, and may indicate exposure oforganisms to contaminants that are not identified from discrete grab sampling. Comparisons ofcontaminants in tissues of the same speciess collected from different areas may indicate variation inthe contaminant exposure. Five contaminannts (aluminium, arsenic, copper, molybdenum, and zinc)were found, during thewater quality monitoring program(DERM 2011; 2 DERMM 2012 a, b, c EHP2012a, b, d, e, f, g, h, i; DSITIA 2013a, b), too have exceeded the Australian A and New Zealandwater quality guidelines (ANZECC and ARMCANZ 2000).5.1.Mud CrabComparison of the pooled metal and metalloid concentrations in mud m crab hepatopancreas fromeach trip inthis study indicated significant differences between trips but theree was generally noconsistent pattern between trips apart from concentrations of barium and selenium. Barium wassignificantly higher in the mud crab hepatopancreas at reference sites s compared to GladstoneHarbour sites for bothtrips and selenium was significantly higher at a Gladstone sites for both trips(Table 9). Copper andzinc were significantlyy higher at the Gladstone Harbour sites in Trip 1, butthere was no significant difference in Trip 2. Iron was significantlyhigher in Trip 2 at the Gladstonesites. Chromium and lead were significantlyhigher at the reference sites in Trip 1, and cadmiumand mercury were significantly higher in Tripp 2. This may reflect slightly different areas from whichthe crabs were collected. In order to put these results inperspective at a larger scale, comparisonswere madewith historical data collected in estuarine and near coastal locations.Comparison of concentrations off metals andd metalloidsin the hepatopancreas of mud crabscollected from the Gladstone Port Development Area (Gladstone Port) P and the Narrows (GladstoneNarrows) in2012 (Figure 1) showed that crabs from these sites did not have higher level of metalsand metalloids in theirhepatopancreas compared to mud crabs collected fromm other estuarine andnear-coastal regions of eastern Queenslandd (Figure 2 to Figure 12). Mean measuredconcentrations of aluminium, arsenic, barium, cadmium, chromium, iron, mercury, nickell andselenium ( Figures 2 to6 and Figures 8 to 11) in the Port Development Area tended to liein thelower half of the measured concentrations of samples collected along the eastern coast ofQueensland. Mean measured concentrations of copperand zinc ( Figure 7 and 12) in thePortDevelopment Area were in the upper half of f the historical data. Andersen (2003) also found thesetwo metalsto be elevated in crabhepatopancreas in Gladstone Harbour compared to a referencesite at Ayr.A direct comparison of the hepatopancreasmetal concentrations from the current studycannot be made with data presented in Andersen (2003) as in the latter the data were reported aswet weight. The concentration off zinc measured in the crab hepatopancreas in the PortDevelopment Area in 2012 was lower than that reported by Mortimer (2000) in the Gladstone area,although the concentration of copper in the hepatopancreas was higher. h Angel et al. (2012) foundthe copperconcentration in water in Gladstone Harbour had increased from previous studies andsuggested this was caused by increased shipping. Measured concentrationsof mercury in the PortDevelopment Area were in the higher half off the historical dataset, , but were much lower thanmeasured concentrations in mudcrabs fromthe Tully, Herbert, and Gordon catchments(Figure 9).Silver was not measured in mud crab hepatopancreasin the previous studiess and so historicalPage 12