Metals Add To Lake Macquarie Fish Defect Risk

[Catchin Jack]

Found this in the Newcastle Herald, here's the link if you want to read it but also putting it in here. Newcastle Herald

HEAVY metal contamination in Lake Macquarie fish is at levels that cause fish deformities and impair their reproduction, a study has found.

Lake Macquarie fish had elevated levels of of selenium, lead, cadmium and zinc in muscle and gonad tissues, a NSW Department of Environment and Climate Change and University of Canberra study said.

A separate University of Sydney report has found that heavy metal contaminants are spreading from the lake's north to its south.

Lake Macquarie City Council said it would consider erecting more warning signs around the lake.

Hunter New England Health said it was OK to eat the lake's contaminated fish, as long as they were not consumed in large quantities.

But the health authority has urged people to be cautious about eating fish caught around power stations and Cockle Creek, where the contaminants are most prevalent.

In the first study, metals in yellowfin bream, silverbiddy, trumpeter whiting and two goby species were compared with the same species in Port Stephens, Forster's Wallis Lake and St Georges Basin at Jervis Bay.

Lake Macquarie fish were found to have "significantly higher" selenium, lead and cadmium concentrations than fish from the other lakes.

Zinc levels in fish were also high, but not considered as bad as other metals.

High levels of heavy metals were in the lake's sediments.

"These metals are a legacy of more than 100 years of industrial activity . . . and urban development," the study said.

This included the former Pasminco lead and zinc smelter at Boolaroo in the lake's north, coal-fired power stations at Eraring in the lake's west and Vales Point to the south.

Selenium levels in the muscle and reproductive tissues of Lake Macquarie fish were "just below or the same as concentrations shown to impair the reproductive success of freshwater fish populations in the United States".

"It would have been expected that some increase in rates of fish larvae deformities would be found lake-wide," the study said.

Hunter New England Health public health physician Dr David Durrheim said health authorities had considered the effects of humans eating Lake Macquarie fish contaminated with heavy metals.

"The metal most prevalent across the lake was selenium, all the others were below levels that one could be concerned about in fish," Dr Durrheim said.

"An adult weighing 70 kilograms would have to eat more than 1.35 kilograms a week of Lake Macquarie fish before you started getting into an area exceeding conservative guidelines [for selenium]."

For children, the figures were proportionally decreased.

"One would have to take in more than 17 times the national mean intake of fish to get up to the levels to be concerned about selenium," Dr Durrheim

said.

Cheers,

Leo

[bluebottle18]

What about testing the prawns caught in the lake. Would they be affected by the pollution.

[steze]

I never knew Lake Macquarie was ever like that. Always thought it was just cooks, georges etc.