195,500 particles of microplastic **per gram** of apple? 126,150 particles **per gram** of broccoli?

[Alex K Chen]

https://www.sciencedirect.com/science/article/pii/S0013935120305703

https://www.dailymail.co.uk/sciencetech/article-8459727/Microplastics-contaminating-fruit-vegetables-eat-including-apples-lettuces.html

I fainted when I read this… If there’s any source of consolation, how many particles of air pollution do we breathe in per day? (given an average µg/m³ of 10) And are the numbers *worsening* over time (this is the big uncertainty)

posting more thoughts here -https://forum.longevitybase.org/t/how-to-reduce-microplastics/126 and https://www.rapamycin.news/t/195-500-particles-of-microplastics-per-gram-of-apple-126-150-particles-per-gram-of-broccoli/4734/10

Edited January 2, 2023 by InquilineKea

[Alex K Chen]

 

Quote

 

220 million

 

The Total: 220,000,000 Particles!

Wow, we're breathing around 220 million tiny PM2. 5 particles every day, or just over 2,500 per second. Looking at their weight, in one day we're breathing 622 micrograms of PM2.May 24, 2017

 

^This is in Beijing though, so for US air pollution you can multiply it by 10/72 (also decrease for 35% of time spent outdoors). Whatever it is, even at a healthy pollution of 7.2 ug/m^3, it’s 22 million PM2.5 particles per day…

meanwhile, using this logic, if you eat a kg of an apple each day, then that’s 195 million particles of plastic PER kg… (and if you eat 3 kg of food), that’s almost 600 million particles of plastic per kg. It’s then not entirely clear if we’re exposed to more pollution from air or from our diet…

 

Edited January 2, 2023 by InquilineKea

[mccoy]

When speaking of respirable dusts (PM 2.5 is a subset of respirable dust which which has a size cutoff of 5 microns), usually concentration and not number of particle is provided (number of particles is an unknown variable since they vary in size from almost zero-aerosols to 2.5 microns).

Also, the composition of the PM2.5 fraction is fundamental. It may contain particularly biologically aggressive compounds, which can lower the thresholds for a generic PM2.5 fraction. The thresholds levels provided by EPA are the following. I 

Edited January 2, 2023 by mccoy

[Alex K Chen]

https://www.usda.gov/media/blog/2019/08/30/trees-can-do-dirty-work-waste-cleanup

(bigger trees "clean up more waste")

but this means the fruits of bigger trees may be more contaminated..

https://acsess.onlinelibrary.wiley.com/doi/full/10.1002/jeq2.20264

Vascular plants take up more MPs. Seaweed is not vascular, and MP contamination is worse in soil than oceans, so maybe eat more seaweed (it's always in plastic but now it appears that the *plastic within vegetables* is higher than the plastic transferred from the packaging..

https://en.wikipedia.org/wiki/List_of_hyperaccumulators

wow sunflowers and rapeseed hyperaccumulate A LOT...

Edited January 10, 2023 by InquilineKea

[Alex K Chen]

Quote

Our hypothesis was that microplastics were ubiquitous in the environment and that their concentration peaks follow the intensity of fertilizer use (phosphorus), soil heavy metals concentrations derived from nearby mining operations (Zn and Cu), and distance to roads and urban areas. We did find evidence of microplastic pollution in crop lands and pastures (306 ± 360 and 184 ± 266 particles kg⁻¹, respectively), but we did not observe pollution of rangelands and natural grasslands. Distance to mining operations, roads, or urban areas did not increase the microplastic particles count. Our observations contradict the common belief that microplastics are ubiquitous in the environment and relate the pollution problem more to agricultural activities

https://www.sciencedirect.com/science/article/pii/S0048969720354462

 

 

Quote

 

On crop lands where farmers use fertilizers to increase crop yields, excess application may lead to higher levels of soil nutrients (Corradini et al., 2019a; Tiecher et al., 2017). However, does fertilizer overuse concur with other environmental threats such as microplastics accumulation? In other words, does a soil managed by a farmer who only loosely adheres to best management practices have more chances of becoming polluted with microplastics? Our data suggests that this is not the case, but this is only the first time this question has been posed and taken into consideration.

Piehl et al. (2018) observed that microplastic pollution of crop lands is higher due to anthropic pressure, even when no plastic covers or microplastic-containing fertilizers are used. Unfortunately, they did not evaluate the relation between high nutrient availability and microplastic pollution as their study area was limited to half a hectare and one agricultural management regime. Similarly, the increasing body of literature that reports (micro)plastic pollution in crop lands where farmers do use plastic mulch to improve soil conditions also disregards the possible relation between (over)fertilization as an indicator of anthropic pressure—and loose application of best management practices—and microplastics accumulation (see Qi et al. (2020) for a comprehensive review on the topic). Most certainly, researchers have disregarded this connection because they have addressed only highly productive crop lands where fertilizer use is—more or less—similar across sites.

In this regard, it is important to note that not all nutrient sources—fertilizers and amendments—transport microplastics to soils. There is no evidence of inorganic fertilizers being a source of microplastics pollution. To date, the literature attributes this role only to sludge, compost, and animal dung (Corradini et al., 2019b; van den Berg et al., 2020; Watteau et al., 2018). Further research is needed to expand or revise this claim, as our data points to crop lands as being the most likely soils to receive microplastics, but did not identified the pollution source.

Almost all studies that qualify microplastics found in soils report polyethylene and polypropylene as the most common parent materials of the recovered microplastics (Qi et al., 2020). Our study follows this trend, and has added polystyrene and acrylates to the list. Our findings confirm those of Piehl et al. (2018) who qualified 12.5% of the microplastics they observed in their assessment of the German farm as polystyrene. And we are the first to report acrylates in soil samples. This polymer is used to extrude fibers so, as the most common microplastic shape we observed in our study was fibers, this relationship could be a possible explanation for why acrylates predominate in our results. Previous studies reporting microplastic fibers in soil samples have not indicated the fibers' polymer type (Corradini et al., 2019b; van den Berg et al., 2020; Zubris and Richards, 2005). This is probably because placing a fiber of less than 1 mm in the ATR unit of an FTIR is an analytical challenge. Researchers studying microplastic pollution of aquatic ecosystems solved this problem by using FTIR microscopes—as we did, although the detection of fibers along poses challenges (Primpke et al., 2019), and was a limitation that affected our observations as well.

 

 

Edited January 10, 2023 by InquilineKea

[Alex K Chen]

https://news.unl.edu/newsrooms/today/article/nebraska-study-finds-billions-of-nanoplastics-released-when-microwaving/

[corybroo]

I’d gotten used to the “They’re everywhere” headlines such as How microplastics are infiltrating the food you eat    Most of these articles mention potential risks and conjectures about the affect on human health.  So the following article caught my attention.  Effects in humans are still unproven but the findings reported in the article make such effects seem more plausible.

Nanoplastics promote conditions for Parkinson's across various lab models, study shows

Nanoplastics interact with a particular protein that is naturally found in the brain, creating changes linked to Parkinson's disease and some types of dementia.

"Parkinson's disease has been called the fastest growing neurological disorder in the world," said principal investigator, Andrew West, Ph.D., professor in the Department of Pharmacology and Cancer Biology at Duke University School of Medicine. "Numerous lines of data suggest environmental factors might play a prominent role in Parkinson's disease, but such factors have for the most part not been identified."

nanoparticles of the plastic polystyrene—typically found in single use items such as disposable drinking cups and cutlery—attract the accumulation of the protein known as alpha-synuclein.

West said the study's most surprising findings are the tight bonds formed between the plastic and the protein within the area of the neuron where these accumulations are congregating, the lysosome.

 

[Alex K Chen]

This is polystyrene, which is uniquely toxic. Other microplastics are more prevalent and less avoidable.

...except not from a 2024 CU study...

Edited January 13 by InquilineKea

[Alex K Chen]

https://time.com/6339914/plastic-alternatives-pollute/?utm_source=roundup&utm_campaign=20230202

[Alex K Chen]

https://www.sciencedirect.com/science/article/pii/S0269749123022352?via%3Dihub

This is all per gram - plant based meats produced a good fraction of MPs per gram. The vast majority - 90s - of particles were  MP.. Not sensitive enough to detect nanoplastics...

Edited January 13 by InquilineKea

[Alex K Chen]

Magnified images of the microplastics detected in the analysed samples by SEM-EDS are reported in Figure 4.

 

Figure 4

Microplastic images under a scanning electron microscope, at different magnifications.

The polymers characterization by ATR-FTIR revealed the highest matchings with three main polymers: Polyethylene low density (PE) (in 60% of the samples; best match 88.66% and 79.47% avg.), Polypropylene (PP) (in 20% of the samples; best match 78.38% and 71.46% avg.) and Polyethylene terephthalate (PET) (in 20% of the samples; best match 73.16% and 70.02% avg.) (Figure 5).

 

Figure 5

Results of the polymer’s characterization by ATR-FTIR. (A) Poly(ethylene), low density; (B) Polypropylene; (C) Poly(ethylene) terephthalate.

[Alex K Chen]

This from Turkey

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10455475/#

Whether 100k or 5 particles per **gram** is far too much

[Saul]

IMO, breathing in nanoparticles is a very bad idea for your lungs.

Much less clear is, whether or not eating foods containing nanoparticles of plastics is a significant threat to health (obviously depends ona lot of factors -- including what plastic; how big are the pieces; etc).  Animal studies would be interesting.

But I would guess:  Giving up your raw broccoli, because maybe there are inert nonoplastic particles in it, is unwise.

  --  Saul

[Alex K Chen]

https://pubmed.ncbi.nlm.nih.gov/37499389/

plastic mulches.... really common contamination source in fruits/vegetables..