New signs are being installed around the Derwent to reiterate health advice about eating fish and shellfish from the Derwent estuary.
Director of Public Health, Dr Roscoe Taylor, said the signs in 32 locations would remind members of the public not to eat bream or shellfish from the Derwent estuary, and to limit how much other Derwent fish they eat.
"Certain fish species accumulate more mercury than others, which influences how much we can safely eat," Dr. Taylor said.
Public health advice on Derwent caught fish and shellfish:
- do not eat bream
- limit consumption of flathead and other fish to twice a week
- some people should further limit consumption to once a week, including: pregnant and breastfeeding women, women planning to become pregnant, children aged six years and younger
- if you eat fish from the Derwent it is best to avoid eating fish from other sources in the same week
- do not collect and eat wild shellfish.
When ingested, high levels of mercury can damage the nervous system. Unborn babies and young children are particularly susceptible because their brains are developing.
Derwent Estuary Program Director Christine Coughanowr said despite this advice, occasional reports suggest that locals and visitors are still harvesting shellfish from the Derwent estuary.
"As part of an ongoing awareness campaign the new signs will complement the brochure Should I eat Shellfish and Fish from the Derwent? which helps explain the current advice," Ms Coughanowr said.
Ms Coughanowr also said the current advice built on more than 20 years' of mercury monitoring in the Derwent estuary.
"Over this time we have seen industrial discharges of heavy metals fall significantly, which is testament to industry efforts to reduce historical sources of heavy metal contamination," Ms Coughanowr said.
"The source of the mercury in Derwent Estuary fish is thought to be linked to sediment contamination associated with historical discharges.
"While work is being done on a number of fronts, it may take years for the levels in sediments and seafood to fall to acceptable levels. So it is vital that regular monitoring continues and that the results are made publicly available."
Dr Taylor encouraged Tasmanians to continue to enjoy the health benefits of fish, which are a valuable source of protein, minerals, vitamin B12 and iodine, and are low in saturated fat and contain omega-3 fatty acids.
"Unfortunately, we've seen overseas that when similar advice has been issued, general consumption of fish has dropped.
This has resulted in measurably greater heart disease in that population," Dr Taylor said.
"We don't want to see that happen here, so I would encourage all Tasmanians to keep fish on the menu."
For more information on the Derwent estuary monitoring program, download the brochure Should I eat Shellfish and Fish from the Derwent? atwww.derwentestuary.org.au