Sydney Harbour seafood and dioxins

On this page

• Overview
• Facts About Dioxins and Port Jackson (Sydney Harbour/Parramatta River)
• Test results for Sydney Harbour / Parramatta River seafood

Overview

All commercial fishing in Sydney Harbour has been halted due to elevated levels of dioxins detected in some fish and seafood. The area affected includes all of Port Jackson and it's tributaries.

This is an extension of the December 2005 temporary ban on commercial catches of prawns and of other previous restrictions on fishing in certain areas such as Homebush Bay.

Recreational fishing is not closed but eating of Harbour fish should be limited (see How much can I eat?). Fish can be caught and released.

Facts About Dioxins and Port Jackson (Sydney Harbour/Parramatta River)

1. What are dioxins?

Dioxins are a group of chlorinated chemicals that originate from industrial pollution or are generated in natural processes such as bush fires. They are chemically stable and can stay in the environment for a long time. Dioxins can accumulate in the body fat of animals and humans.

2. Where do dioxins come from?

Residues of dioxins in seafood caught in Sydney Harbour/Parramatta River are likely to have their sources in contaminated sediments on the bottom of Homebush Bay. Current levels are likely due to many years of industrial activities previously along those waterways.

On land, the main source of dioxin emission in Australia is through bushfires and burning of agricultural stubble.

3. What are the health risks associated with dioxins?

We are all exposed to very low levels of dioxin, mostly via the food we eat. At those low levels, there are no known health risks.

Long term high level exposure to dioxins can sometimes cause a range of ill effects, including reproductive disorders and cancer. However, as concluded in the Food Standards Australia New Zealand Risk Assessment report on seafood from Sydney Harbour, the health risk associated with consuming seafood from Sydney Harbour/Parramatta River is low for the average Australian consumer. The Government has closed the Harbour as a precautionary measure.

4. What if I've been eating fish from Sydney Harbour?

An increased health risk associated with dioxins only occurs from long term exposure to high levels of dioxin. It is unlikely that people consuming seafood from Port Jackson would have noticeable health effects from the seafood, even if the dietary advice below is occasionally exceeded (see How much can I eat?).

NSW Health advises people to contact their doctor if they are concerned about consumption of fish from Sydney Harbour/Parramatta River. The risk is considered low.

5. I fish for recreation and I want to eat the catch. How much can I eat?

An Expert Panel has advised the Government that people can continue to eat fish from Sydney Harbour and Parramatta River providing they follow strict dietary advice.

Dietary advice:

• No seafood caught west of the Sydney Harbour Bridge should be eaten. You should release your catch.
• For seafood caught east of the Sydney Harbour Bridge generally no more than 150 grams per month should be consumed.
• Testing of popular species has allowed for more accurate dietary advice. The table below provides advice on the maximum consumption of specific species.

Table: Recommended maximum intake based on eating a single species caught east of the Sydney Harbour Bridge.

Species	Number of 150 gram serves	Amount per month
Prawns	4 per month	600g
Crabs	5 per month	750g
Bream	1 per month	150g
Dusky Flathead	12 per month	1800g
Fan-belly Leatherjacket	24 per month	3600g
Flounder	12 per month	1800g
Kingfish	12 per month	1800g
Luderick	12 per month	1800g
Sand Whiting	8 per month	1200g
Sea Mullet	1 every 3 months	50g
Silver Biddie	1 per month	150g
Silver Trevally	5 per month	750g
Tailor	1 per month	150g
Trumpter Whiting	12 per month	1800g
Yellowtail Scad	8 per month	1200g
Squid	4 per month	600g

Note: 1.) The advice in the table is provided where only one species is being eaten in the month. Each guideline number of serves is therefore the recommended total intake for the month. For example eating 150 grams of Bream and 600 grams of prawns in one month would exceed the recommended intake.

Note 2.) This table will be updated if new results become available. The last update was 19 December 2007.

6. What about commercial fishing?

The NSW Government has suspended all commercial fishing in Port Jackson (Port Jackson is the area inside Sydney Harbour, Parramatta River, Lane Cove River and Middle Harbour).

Fishers with commercial fishing licenses for the Port Jackson area with questions about compensation package should see the NSW Department of Primary Industries information page (external link) or contact that department on 1300 550 474 (local call from fixed telephones).

7. How do I know if fish I’ve bought are from Port Jackson?

All Port Jackson fish and crustaceans have been removed from sale. (Port Jackson is the area inside Sydney Harbour, Parramatta River, Lane Cove River and Middle Harbour).

8. How long do dioxins last?

Dioxins can last for decades in the environment.

Test results for Sydney Harbour / Parramatta River seafood

2007 test results

Tests by NSW Department of Primary Industries have established dioxin levels in 2 additional species: Dusky flathead and Fan-belly Leatherjackets. These have been added to the dietary advice above.

2006 test results

In 2006, the NSW Department of Primary Industries tested a range of common recreational species. These results were used by the Expert Panel to recommend the dietary advice mentioned above.

The test results for the common recreational species can be found on the NSW Department of Primary Industies website, information page (external link).

2005 Testing of Bream and Prawns

The results for both Bream and Prawns are summarised in the charts below. Please note Homebush Bay has been closed to fishing since 1989.

A number of samples were taken from each location.

There are many types of dioxins. The information below is calculated using 29 of the most toxic dioxins present and weighting each based on its toxicity.

 

Note: Further test results can be found on the NSW Department of Primary Industries website, NSW Department of Primary Industries information on dioxins (external link - See question 5).

What do the results tell me?

The results show all edible samples of seafood from Port Jackson are above the current European Union limit.

Greasyback prawns are low, but these are usually only taken for use as bait.

The European Union limit for dioxins in food is 4_TEQpicogram of dioxins per gram of seafood (marked by a green line in the charts above). This is a measure of the amount of dioxin in fish or prawn tissues. One picogram per gram is equivalent to one part per trillion.

There is no consistent international standard on dioxin levels. For example, as mentioned above, the European Union has a limit of 4_TEQpicogram of dioxins per gram of seafood , while the USA previously had a limit of 50 part per trillion although withdrew it in favour of dietary advice. Australia has no maximum standard. The Government has closed the Harbour as a precautionary measure.

The Expert Panel’s dietary information presented above was calculated from these results. This was done by averaging the result for bream and prawns across the waterway (Port Jackson) and then determining an amount of seafood from the waterway people can safely consume each month. It should be noted that occasionally exceeding this advice per month would not be likely to result in a significant health risk.

What about imported seafood?

The NSW Food Authority recently tested imported prawns and fish for dioxins. The dioxin results for the imported seafood were well below the European Union limit of less than 4_TEQpg/g for dioxin.