Tag Archives: seafood

FactCheck: do Australians with an average seafood diet ingest 11,000 pieces of plastic a year?

The Conversation

Britta Denise Hardesty, CSIRO

Well, if you’ve got an average seafood diet in Australia today, you’re probably ingesting about 11,000 pieces of plastic every year. – Dave West, National Policy Director and founder of environmental group, Boomerang Alliance, speaking with a Fairfax video journalist.

Australians are growing increasingly aware of the real danger posed by the vast amount of plastic dumped in our seas every year. It’s an important issue, so it’s crucial we get the facts right.

Ahead of a Senate committee hearing on the threat of marine plastic pollution in Australia, Dave West from the environmental group Boomerang Alliance told a Fairfax video journalist that an average seafood diet in Australia would result in ingesting about 11,000 pieces of plastic a year.

Is that accurate?

Checking the source

When asked for a source to support his assertion, West referred The Conversation to a BBC article published in October 2015 that said:

Prof Tamara Galloway of Exeter University quotes research estimating that anyone consuming an average amount of seafood would ingest about 11,000 plastic particles a year.

The Conversation asked Galloway, a professor of ecotoxicology, to clarify and provide sources. She said by email:

The stats came from another published paper, by [Belgium-based researchers] Van Cauwenberghe and Janssen in which the authors had made a Fermi estimate (or order of magnitude estimate) based on their field data for cultured shellfish.

Professor Galloway also said she had co-written a commentary article for the journal PNAS which

covers a similar topic, but includes some data from another paper too, in which the authors found even higher concentrations of microplastics in seafood. Clearly, there is going to be variation in the levels of contamination depending on location and local sources of pollution, ocean conditions, etc. This does suggest however, that the Van Cauwenberghe results are not just a one-off.

You can read Professor Galloway’s full reply here.

The 2014 Van Cauwenberghe and Janssen paper to which Galloway refers was published in the journal Environmental Pollution.

However, that paper does not show that anyone consuming an average amount of seafood would ingest about 11,000 plastic particles a year. The figure of 11,000 is an upper-end estimate for Europeans who eat quite a lot of molluscs. The paper estimates that:

European top consumers will ingest up to 11,000 microplastics per year, while minor mollusc consumers still have a dietary exposure of 1800 microplastics year.

In that paper, the researchers note that shellfish consumption differs greatly among countries.

In Europe, for instance, mollusc consumption can differ over a factor of 70 between consumers and non-consumers. European top consumers can be found in Belgium (elderly), with a per capita consumption of 72.1g day, while mollusc consumers in France (adolescents) and Ireland (adults) have the lowest per capita consumption: only 11.8g day for both countries.

The researchers also noted that

The presence of marine microplastics in seafood could pose a threat to food safety, however, due to the complexity of estimating microplastic toxicity, estimations of the potential risks for human health posed by microplastics in food stuffs is not (yet) possible.

What does this mean for the average Australian seafood consumer?

The 11,000 figure applies to an estimate for “European top consumers” of molluscs, not an average Australian seafood diet.

We don’t yet have all the data needed to make a good estimate of how much plastic an average Australian seafood consumer ingests per year.

The Boomerang Alliance’s Dave West acknowledged the limitations of applying the 11,000 figure to Australia, telling The Conversation by email that:

Only comment I’d make is that I agree the comment referring to Australia rather than a generic average seafood diet was clumsy.

Small plastic particles can be ingested by bivalves (such as mussels, cockles, oysters, pipi and scallops) and remain there for some time. And these bivalves can be eaten by larger predators, pushing the plastic up the food chain.

It’s worth noting the important difference between eating fish and shellfish. Unless you’re eating sardines and anchovies, humans don’t typically consume the digestive tract of a fish (where plastics would be found). But if you’re eating molluscs and shellfish, particularly from urban centres, you may be adding plastic to your diet.

Australians are not the world’s top shellfish consumers, trailing behind Belgium, most East Asian countries, the US and many European nations.


There is insufficient published research to support the statement that a person with an average seafood diet in Australia today is probably ingesting about 11,000 pieces of plastic every year.

The 11,000 figure applies to an estimate for “European top consumers” of molluscs, not an average Australian seafood diet. This is an important issue that needs more attention. – Britta Denise Hardesty


This article is factually correct and represents a sound analysis.

In fact, our own studies found levels of microplastics in mussels from the Dutch coast that are one order of magnitude higher than those reported in the 2014 Belgian study by Van Cauwenberghe and Janssen: 13.2 particles per gram of mussel.

However, it should be noted that microplastics are everywhere and that humans are broadly exposed to them through the food. For example, microplastics have been recently detected in a range of terrestrial products such as milk, beer, honey and sea salt. Therefore, an analysis and assessment of the potential health risk of microplastics for humans should comprise dietary exposure from a range of foods across the total diet, in order to assess the contributing risk of contaminated marine food items.

Although it is evident that humans are exposed to microplastics through their diet and the presence of microplastics in seafood could pose a threat to food safety, our understanding of the fate and toxicity of microplastics in humans constitutes a major knowledge gap that deserves special attention. – Dick Vethaak

Have you ever seen a “fact” worth checking? The Conversation’s FactCheck asks academic experts to test claims and see how true they are. We then ask a second academic to review an anonymous copy of the article. You can request a check at checkit@theconversation.edu.au. Please include the statement you would like us to check, the date it was made, and a link if possible.

The ConversationBritta Denise Hardesty, Senior Research Scientist, Oceans and Atmosphere Flagship, CSIRO

This article was originally published on The Conversation. (Reblogged by permission). Read the original article.


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Like eating fish? It’s time to start caring where it comes from

The Conversation

By Carissa Klein, The University of Queensland

Australians love seafood. Whether it’s fish and chips by the seaside or prawns on the barbie at Christmas, it’s integral to many of our traditions and social gatherings. Yet very little of the seafood we consume is sustainable. For a country that has such a love affair with the ocean, I find this perplexing.

The health of the world’s oceans and its fisheries are in decline, and this applies to one of Australia’s most precious icons, the Great Barrier Reef. Although there a range of actions required to reverse this decline, one simple thing that anyone can do is stop eating unsustainable seafood.

But why isn’t this already happening? There’s a lack of awareness and action, as will hopefully be highlighted by the new SBS documentary series What’s the Catch?. The good news is that there are simple things we can do about this problem.

Sustainable seafood can be defined in various ways, but as Australia’s Sustainable Seafood Guide (and its counterparts around the world) makes clear, sustainability is not only about the status of individual species stocks, but the impact of fishing on our oceans, which includes the broader effects of fishing on habitats and ecosystems.

Three key steps to sustainability

Here are three key things that are needed to shift Australia’s love for seafood from unsustainable to sustainable.

1. Leadership from the marine conservation community

As a marine conservation scientist, I’m continuously struck by the prevalence of unsustainable and/or unlabelled seafood at science and conservation meetings and social gatherings.

This observation prompted me and some colleagues to assess the sustainability of seafood served at seven marine ecology and conservation meetings held in Australia (attended by over 4000 people from around the world). To score them, we used a publicly available guide which considers population stock status and the impact of fishing or aquaculture method.

Our results showed that seafood was served at all the meetings, and at more than half of the meetings at least one unsustainable species was on offer. Only about a third of the meetings offered a sustainable choice. If marine conservationists struggle to eat sustainable seafood at their own meetings, what hope is there for everyone else?

Marine scientists and conservationists urgently need to turn science into action, and to lead by personal example.

2. Easily accessible sustainable seafood

As a consumer of seafood, I want sustainable options. However, I usually find that the average fish and chip shop or restaurant has few (sometimes no) sustainable options on the menu.

There are restaurants that specialize in sourcing sustainable seafood (such as Swamp Dog in Brisbane); a great initiative but all too rare. What we need is to be able to head to the local fish and chip shop, perhaps after a day at the beach, and reliably find sustainable choices.

And as much as we need easy access to sustainable seafood, we also need there to be no access to clearly unsustainable seafood. For example, it’s common to see Orange Roughy on menus, despite it listed widely as an unsustainable choice and even listed as “conservation dependent” under Australia’s Environmental Protection and Biodiversity Conservation Act.

Another problem with sourcing sustainable seafood is inconsistency in seafood guides. Fish that your local supermarket claims is sustainable may not be labelled as such in other guides. Who do you trust? I usually end up walking away empty-handed, but who can blame shoppers for going ahead and buying it anyway if they’re told it’s a responsible choice?

In some ways, the problem is similar to the difficulty of finding a range of organic vegetables at the local fruit and veg shop or supermarket. One way that this has been addressed in agriculture is through “fruit and veg box” schemes, in which you choose a provider you trust to supply you with sustainably grown (organic and local) vegetables.

Similar schemes for seafood, such as this one in Santa Barbara, California, are still rare. There’s no doubt that a project like this would help consumers in Australia eat more sustainable seafood.

3. Stronger labelling laws

Unlike in Europe, Australia’s seafood labelling laws are weak. When you order cooked seafood, you can’t be sure of where it is coming from (Australia or overseas) or what species you are eating, despite what the vendor tells you.

You may have thought your last order of barramundi was a good choice – either sustainably farmed or locally caught. But more than two-thirds of the barramundi consumed in Australia is imported.

If we can’t rely on labels in fish and chip shops or restaurants, how can we choose sustainable options? This is the focus of the Label My Fish and of the new SBS series.

Australia is viewed as a global leader in marine conservation by many other countries, primarily due to the rezoning of the Great Barrier Reef Marine Park in 2004, which set aside 33% of its area as no-take zones. This reputation is now at stake.

To be a true leader, Australians will need to make some serious modifications to the seafood market to ensure that it is more sustainable. As stated by the Centre for Policy Development’s recent report on fisheries management, “Australia could be a leader in sustainable seafood production”.

But first we have to care what’s on our plate.

The ConversationCarissa Klein does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published on The Conversation. (Republished with permission). Read the original article.

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