Summary
Read the full fact sheet- People who fish in the Lower Yarra and Maribyrnong rivers need to be careful about eating their catch.
- Industrial pollutants including chemicals known as polychlorinated biphenyls (PCBs) may be found in high levels in certain fish, including eel and black bream.
- This advice is for people who fish in the Lower Yarra and Maribyrnong rivers – contact your local council for information and referral if you fish in other waters.
On this page
- About fish
- Fish from the Lower Yarra and Maribyrnong rivers
- Ask your council for advice in other areas
- Polluted waters – the risk of PCBs
- Eating fish from flood affected waters
- Health effects of PCBs
- Reduce the risks of consuming PCBs
- PFAS in fish
- Shop-bought fish and mercury
- Health benefits of eating fish
- Where to get help
About fish
Fish are an important part of a healthy diet. They are high in protein and other essential nutrients, low in saturated fat and contain omega-3 fatty acids.
In general, the benefits of eating fish greatly outweigh any risks.
Fish from the Lower Yarra and Maribyrnong rivers
People who fish in the Lower Yarra and Maribyrnong rivers need to be careful about eating their catch.
The risks of eating your catch can be reduced if you make sensible choices about the type and amount of fish you eat.
Ask your council for advice in other areas
This fact sheet offers advice to people who fish in the Lower Yarra and Maribyrnong rivers. If you fish in other waters, please contact your local council for information and referral.
Polluted waters – the risk of PCBs
Over time, urban waterways can become polluted with chemicals. Fish may take up some of these chemicals into their bodies. There are several chemicals that can build up in fish. The main ones that can be a problem in the lower Yarra and Maribyrnong rivers are polychlorinated biphenyls (PCBs).
PCBs were used from the 1930s to the 1970s in industrial products. They have now been phased out, but they stay in the environment for a long time.
Mercury may also be found in certain Victorian inland waters where it was once used for gold extraction. Mercury can also remain in the environment for a long time.
PCBs can build up in the human body. If a person eats large amounts of contaminated fish, these PCBs may affect their health.
Women who are pregnant or may become pregnant are the most likely to be affected. PCBs in a mother’s body can affect the development of her unborn baby’s brain.
Young children are also at increased risk.
Eating fish from flood affected waters
Water from floods is usually contaminated and not safe for fishing. The Environment Protection Authority Victoria monitors the water quality results of flood-impacted waterways.
Do not eat fish from flood waters or flood impacted rivers.
Health effects of PCBs
Some of the known health effects of PCBs include:
- learning problems and developmental delay in children
- skin complaints such as acne or rashes
- liver problems
- changes to the immune system
- changes to the hormone system, including impaired functioning of the thyroid gland.
The potential health effects of low level exposure to PCBs are complex and still need further investigation.
Eels pose the greatest risk of PCBs
Chemicals such as PCBs tend to concentrate in the fatty parts of a fish’s body. Eels have a higher fat content than other fish, so tend to carry higher amounts of PCBs.
A 2005 study of contaminants in fish from the Lower Yarra and Maribyrnong rivers showed 2 in every 15 eels exceeded the maximum safe limit of PCB levels.
A more detailed study in 2006 found PCB levels in eels and fish tested did not exceed the maximum safe limit.
In 2009, a study of contaminants in the Lower Yarra showed a decrease in median PCB levels in black bream fish compared to the 2006 study results.
Black bream are higher in PCBs than other species of fish, while mullets have comparatively lower levels of PCBs than eels and black bream.
Reduce the risks of consuming PCBs
Risk reduction tips include:
- Women of childbearing capacity and children aged less than 16 years should not eat caught eels. Everyone else should limit eating the eels they catch to one serve per month.
- Women of childbearing capacity and children aged less than 16 years should limit eating other caught fish to one serve per month. Everyone else should limit eating the fish they catch to 4 serves per month.
- The above recommendations apply to 150g serves of fish. Weigh your fish portions to make sure you are not exceeding 150g per serve.
- Try to eat smaller, younger fish, as these are likely to have fewer pollutants than older, larger fish. However, make sure the fish are within legal size limits.
- Clean and cook fish properly. Remove skin, fat and internal organs before cooking, because some chemicals concentrate in the fatty parts.
- Grill or bake fish instead of frying.
Remember that these precautions only apply to fish caught from the Lower Yarra or Maribyrnong rivers. These precautions do not apply to shop-bought fish.
PFAS in fish
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a group of over 4,000 types of manufactured chemicals, including:
- perfluorooctane sulfonate (PFOS)
- perfluorooctanoic acid (PFOA)
- perfluorohexane sulfonate (PFHxS).
Products containing PFAS include carpets, non-stick cookware, and in the past, fire-fighting foams. We are likely to be exposed to low levels of PFAS, mostly from eating food or drinking water containing PFAS. This is unlikely to be harmful to our health.
Animal studies have shown some links between PFAS exposure and health effects, but there is no consistent evidence that PFAS are harmful to human health at levels found in the environment.
Australian health-based guidance values for PFOS, PFHxS and PFOA in food, drinking water and recreational waters have been set for use in site investigations.
Testing of fish in Victorian waterbodies has shown varying PFAS concentrations, with some exceeding health-based guidance values for food.
In May 2019, a risk assessment of PFAS levels in fish caught from the Maribyrnong river led to an alert recommending fish caught from the Maribyrnong river upstream of Solomons Ford in Avondale Heights to Deep Creek at Bulla and within all of Arundel Creek not be consumed.
PFAS can persist for a long time, both in the environment and in humans, so as a precaution, it is recommended that exposure to PFAS be minimised when possible.
Shop-bought fish and mercury
A well-balanced diet that includes fish can have lots of benefits for health, including heart health, and children’s growth and development. However, some fish you buy may have increased levels of mercury.
Mercury is a metal that can build up in the human body, and damage the nervous system and kidneys. If pregnant women have too much mercury in their body, their children may be at risk of learning problems and developmental delays.
Generally, mercury from most fish sold in Australia is not a health risk for healthy adults and children, when eaten in reasonable amounts.
Fish that are predatory (eat other fish), large and are at the top of the food chain tend to contain more mercury. Pregnant women, women of child-bearing age and young children (under 6 years) should eat predatory fish such as shark (flake) or swordfish no more than once a fortnight. For the rest of the population, this is no more than once a week.
Health benefits of eating fish
Some of the many health benefits of eating fish once or twice every week include:
- lowered blood pressure
- boosted levels of ‘good’ blood cholesterol
- reduced risk of heart disease
- reduced risk of dementia.
Where to get help
- Your GP (doctor)
- Your local council
- Environment Protection Authority Victoria Tel. 1300 372 842
- 2009 Lower Yarra river fish study, Environmental Protection Authority Victoria.
- FAQs for polychlorinated biphenyls (PCBs), Agency for Toxic Substances and Disease Registry, Department of Health and Human Services, US.
- Consumption advice for recreationally caught fish, 2021, Environment Protection Authority Victoria.
This page has been produced in consultation with and approved by: