"How Much Microplastic Is Found in Fish Fillets?"
Microplastic pollution of our waterways may not just represent a threat
to marine ecosystems but also to human health.
It’s evident we’re exposed to microplastic pollutants in seafood,
which may create a food safety risk,
but is there some seafood less contaminated than others?
The first published study looked at mollusks.
Eating an average serving of mollusks you consume around 90 plastic particles,
whereas an average serving of oysters may contain only around 50.
As a result, the annual dietary exposure for European shellfish consumers
can amount to 11,000 swallowed microplastics per year,
though we don’t yet know what kind of risk this would carry.
Of course, due to their persistent nature,
microplastic abundance is only going to get worse.
It is inevitable that humans eating seafood will ingest
at least some microplastics, particularly when the entire creature is consumed,
such as mussels, oysters, and small fish, so, what, like sardines?
We didn’t know… until now.
Contamination with microplastics and mesoplastics,
which are like little pieces of plastic larger than a millimeter.
They looked at 20 brands of canned sardines from 13 countries
over four continents and only found plastic particles in about one in five.
They suggested the disparity may have been due
to improper gutting in the contaminated samples.
But in mammals, at least, ingested microplastics can get through
the gut wall and circulate throughout the body
and even cross the placental barrier.
So, do microplastics actually make it into the muscles of the fish,
like a fish fillet?
Let’s find out.
If you compare the level of microplastics in eviscerated flesh
versus the organs, surprisingly, sometimes the flesh
actually contained higher microplastic loads than the excised organs,
which highlights that evisceration does not necessarily
eliminate the risk of microplastic intake by consumers.
Microplastics of all “colors, shapes, and sizes
were detected in all investigated fish muscle samples;”
so, they do actually get into the flesh.
So, the average intake of microplastics from eating flathead,
grouper, shrimp, scad, or barracuda may be
in the hundreds per 300 gram serving or just in the dozens
of plastic particles in a two-ounce child serving.
Besides the plastic itself, the particles may release
absorbed pollutants like PCBs, and also release plastics chemical additives
like BPA, which collectively may cause
hormone disruption, cancer risk, and DNA damage.
Hence, although there is no standard tolerable dose
for microplastics ingestion, as well as information on exact toxicity
of different plastic types in the human body,
taking weekly servings of these kinds of fish may threaten
the health of consumers, especially vulnerable groups
including pregnant and breastfeeding women and children.
In the US, anthropogenic debris, meaning man-made materials,
were found in a quarter of individual fish
and in two-thirds of all fish species tested,
and also about a third of individual shellfish samples,
demonstrating that man-made debris has infiltrated
the aquatic food chain up to the level of humans via seafood.
Because this debris is associated with a cocktail of pollutants,
this validates the concern that the “debris may be transferring
[these chemicals] to humans via diets containing fish or shellfish,
raising important questions regarding the bioaccumulation
and biomagnification of chemicals, and consequences for human health.”
Now this study also included non-plastic debris like foams, film, and fibers,
but we know now that the ingestion of microplastics
appears to be a widespread and pervasive
phenomenona across a number of commercially important
mollusks, crustaceans, and fish.
So, the potential for humans, as top predators,
to consume microplastics as contaminants in seafood is very real,
and its implications for health need to be considered.
“Despite the existence of considerable uncertainties and unknowns,
there [may already be] a compelling case for urgent actions
to identify, control, and, wherever possible,
eliminate key sources of microplastics
before they [ever make into our oceans.]”