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Would you like a side of plastic with your seafood?

It seems as though you’re going to get it, whether you like it or not.

Millions of metric tons of plastic enter the oceans every year.

Just one look at the Pacific trash vortex, also known as the Great Pacific Garbage Patch, which lies between North America and Japan, is a telltale sign that we have a massive problem. But it’s the microplastics, more specifically, the nanoplastics, which are less than 100 nanometers in size, that are wreaking havoc on marine life and sneaking into our food sources.

An Australian study recently published in the journal Environmental Science & Technology has found plastic in every seafood sample it analyzed. The research suggests microplastics have invaded the food chain to a greater extent than initially thought. Lead author, Francisca Ribeiro, says, “Considering an average serving, a seafood eater could be exposed to approximately 0.7 milligrams (mg) of plastic when ingesting an average serving of oysters or squid, and up to 30 mg of plastic when eating sardines.”

Around 17% of the protein humans consume worldwide is seafood.

The findings, therefore, suggest people who regularly eat seafood are also regularly eating plastic.

The researchers purchased five varieties of seafood: five wild blue crabs, 10 oysters, 10 farmed tiger prawns, 10 wild squid, and 10 wild sardines.

Each sample was weighed and washed to remove any residue of plastic packaging before being dissected. Only the edible part of each species was tested.

The scientists placed each sample into a flask with an alkaline solvent and agitated it at 60 degrees Celsius (140° F) in a shaker incubator. Once the solvent had wholly digested the sample, the solution was analyzed for plastic. The researchers then used a technique called pyrolysis gas chromatography mass spectrometry to identify the presence of five types of plastics: polystyrene, polyethylene, polyvinyl chloride, polypropylene, and poly(methyl methacrylate), all of which are commonly found in packaging, synthetic textiles, and marine debris.

Ribeiro said of their conclusion, “Our findings show that the amount of plastics present varies greatly among species, and differs between individuals of the same species.” Explaining further, “Each of the analyzed seafood species of this study has different biological, physiological, and anatomic features and lives in different compartments of the marine environment, which influences the uptake and potential accumulation of microplastics.”

They found the following:

  • 0.04 mg of plastic per gram of tissue in squid
  • 0.07 mg in prawns
  • 0.1 mg in oysters
  • 0.3 mg in crabs
  • 2.9 mg in sardines.

All the samples contained polyvinyl chloride. The largest concentrations of plastic were composed of polyethylene.

“From the seafood species tested, sardines had the highest plastic content, which was a surprising result,” says Ribeiro. A grain of rice weighs about 30 mg, about the same amount of plastic found in a sardine.

Co-author Tamara Galloway, from Exeter University, said, “We do not fully understand the risks to human health of ingesting plastic, but this new method will make it easier for us to find out.”

The researchers suggest that plastic may make its way from an animal’s gastrointestinal tract to its edible parts during processing, including gutting — if performed incorrectly — and general handling. Plastics may also attach themselves to seafood via “airborne particles, machinery, equipment and textiles, handling, and from fish transport.”

It’s also important to note the packaging may come into play as researchers found a high concentration of plastic in sardines, noting that

the fish was purchased in bags made of low-density polyethylene, which, when opened, can result in the shedding of microplastics. They warn that these types of packaging could be an additional and significant pollutant for seafood.

Scientists have previously found microplastics and nanoplastics in sea salt, beer, honey, and bottled water. They can also deposit on food as dust particles.

So never eat seafood again? Of course not. But you SHOULD look for the freshest, wild-caught seafood you can get, while also taking steps to make sure you’re processing toxins out of your body as consistently as you should be. If you’re not sure whether you are or not, set up a time for a consultation with Joyce Gibb!