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I just saw a DW (Deutsche Welle the German public state own international broadcaster) short documentary on You-Tube named "How to avoid micro plastic in your food" and is about how much plastic we are eating. Please seek to time 3:46.

In that, it is explained that plastic in turn breaks in very small fragments called micro-plastic, which are less than 5mm in size.

This micro plastic in our oceans is consumed by sea creatures in turn reach our bodies through them, also we inhale tiny free plastic molecules in air through our breathing.

There is a claim in the video that we eat 5g of plastic per week, a weight equal to a credit card in such a ways.

Are we eating 5g of plastic per week through various ways knowingly or otherwise?

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    Near miss: This paper models US consumption of microplastics, but in terms of the count of particles, not their weight and I can't figure how to get from one to the other without my own, untrustworthy modelling.
    – Oddthinking
    Oct 21 at 21:06
  • Regardless of the actual amount eaten, the significant number is how much doesn't simply pass through. Oct 22 at 23:24
  • I ever more find DW videos to be extremely dubious. They tend to make wide, sweeping, claims and then resort to "experts" who are anything but and are presenting personal opinions as fact.
    – jwenting
    Oct 28 at 17:57
  • @jwenting - Hmm , but that is somewhat true about all the media outlets also . For instance BBC reel a short video site also makes such claims in their videos , I don't want to criticize anybody , but I too sense somewhat exaggeration in these short videos as I often watch them. Perhaps that is their Selling point. Make a big impact on mind of viewers in 5-10 mins and to attract and maintain viewer base. Oct 28 at 19:20
  • @SwiftPushkar ikr It's propaganda, best served in short sound bites as most of the target audience 1) can't keep their attention longer, 2) won't question them, 3) doesn't know better
    – jwenting
    Oct 29 at 3:15
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I think this is rather disputed. The 5g figure appears to have originated with Reuters Singapore based on an Australian study, and it's even pegged as a "conservatives estimate" therein.

On the other hand

researchers from Wageningen University & Research calculated that we ingest about 0.0041 mg microplastics particles a week (less than a grain of salt) and 12.3 mg in a lifetime.

i.e. that most people consume less than the equivalent of a salt crystal of plastics:

enter image description here

According to the abstract of the Dutch study that spurred that large graphic:

Microplastic (1–5000 μm) median intake rates are 553 particles/capita/day (184 ng/capita/day) and 883 particles/capita/day (583 ng/capita/day) for children and adults, respectively. [...] Simulated microplastic concentrations in stool agree with empirical data.

However, the modelling is rather involved, as it entails knowing the distribution of particles by weight etc. So I suspect there might not be agreement on this, in the literature.

According to the Canadian study found by Oddthinking, the largest single contributor appears to be bottled water (it has 22-times the plastic contents of tap water by particle count). That study says that Americans, on average, drink one 0.5L (well 0.436L) bottle of water per day, with the rest of water intake from other sources. Also

The items considered in this study were determined to have the following average microplastic concentrations: seafood = 1.48 MPs/g, sugar = 0.44 MPs/g, honey = 0.10 MPs/g, salt = 0.11 MPs/g, alcohol = 32.27 MPs/L, bottled water = 94.37 MPs/L, tap water = 4.23 MPs/L, and air = 9.80 MPs/m3.

As Oddthinking notes, it's not really clear how to translate these into weights. Assuming the particle counts are remotely proportional with with the weight, that makes bottled water the largest contributor.

But a 0.5L plastic water bottle weights like 10 grams, so there would have to fairly large leaching (on the order of 5% by weight) to drink half of the mass of one container even a week if all water drank was from such bottles (14 liters = 28 bottles), and even more leaching would be needed if only one bottle per day was drank (American average), i.e. ~20% leaching.

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    who are these people eating the equivalent of 200 credit cards per week?
    – user253751
    Oct 25 at 10:41
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    @user253751 They maxed out the credit cards and couldn't afford food.
    – Unfair-Ban
    Oct 25 at 10:48
  • @user253751 where are you getting this number from? Oct 25 at 11:41
  • @linuxUser123 the graph
    – user253751
    Oct 25 at 11:42
  • @user253751: probably nobody; the maximum values appear to have been extrapolated from excretion in rats.
    – Fizz
    Oct 25 at 17:51

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