CSIRO finds rising dissolved metal levels in Gladstone Harbour

SHANGHAI,May. 10 -- According to the preliminary data from the General Administration of Customs, China's imports of unwrought copper and copper semis were 375,258 mt during April, with YTD imports from January to April at 1,735,958 mt, up 48.8% YoY. China's imports of scrap copper were 370 kt during April, with YTD imports from January to April at14.3 million mt, up 4.1% YoY.

A three day study of Gladstone Harbour prepared by the CSIRO has found levels of heavy metal contamination were below water quality guidelines.

The CSIRO has noted the rising dissolved aluminium and copper levels in Gladstone Harbour and has recommended extra fish tissue samples be taken due to the high public interest.

A separate state government study released last month found dissolved aluminium levels at three of the 19 tests sites above water safety levels.

The CSIRO study, conducted over three days in December at 21 collection sites near dredging operations was funded by the Gladstone Ports Corporation which is dredging the harbor. It found the concentrations of dissolved arsenic, cadmium, cobalt, chromium, copper, manganese, nickel, lead and zinc were below water quality guidelines.

However, it found the level of dissolved aluminium was higher than the water quality guidelines used in Australia and New Zealand at the majority of sites sampled. Also, the study found the level of copper had increased since previous CSIRO studies. The increases put the level for dissolved copper only marginally below the safety levels for the metal.

The report said that the dissolved copper concentrations were noticeably higher than the concentrations measured in the CSIRO surveys in December 2003 and 2004 indicating increased inputs of these metals from various sources."

Mr Simon Apte CSIRO's principal researcher said that there were no guidelines for aluminium dissolved in marine waters in the United States or Europe. Australia had tighter water quality guidelines which had a tier of concern levels below set standards. There are no formal guidelines for aluminium in Australia but the concentrations that we measured were above the concern level which is a very conservative level. That should trigger further investigations just to confirm that the aluminum levels don't pose any threat to marine life.

Dr Apte said that aluminium which occurred naturally from the soils, could be very toxic in fresh water but was rarely toxic in marine waters. The world's largest alumina factory, Queensland Alumina Limited has been based at Gladstone since 1967. Fish could get gill infections from high levels of dissolved aluminium but the levels of dissolved aluminium were not of biological concern.

He said that in terms of the increasing dissolved copper concentrations in the harbor waters, the study recommended further research into anti fouling paints being used on boats. There are a number of sources of copper in Port Curtis including release from antifouling paints applied to boats. Given the increased shipping activity in the harbor it is likely that this source of copper has increased over recent years.

Dr Apte said that the research showed slight increases in nickel and copper but not to levels that we should be worried about. It was clear fish tissue sampling from Gladstone Harbour should be made public. The reason why we raised this is because clearly the public is very concerned at fish disease and how this is related.