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, 2024 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, 2024 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..

[Alex K Chen]

https://plastchem-project.org/

[Alex K Chen]

Let's just say that the easiest way to reduce MPs is semaglutide/tirzepatide. They are wrecking our ability to think, our intelligence, our ability to error-correct and self-align.

https://x.com/noor_siddiqui_/status/1792826388644508010

https://x.com/tcampbelltweets/status/1792942385317515471

Michael Woodley noticed that modern humans have lower intelligence than Victorians. This could be the reason. I know he and the alt-right people like to cite the reverse Flynn Effect (and decline of Roman Empire) due to "smarter people in cities breeding less", but we can't leave this to chance.

If you believe in cosmopsychism or Christopher Langan's theory of the universe, this also doubly applies.

We need microplastic-free certified food, and soil certified to be low-microplastics. Our soil is poisoning us.

[Alex K Chen]

https://www.sciencedirect.com/science/article/pii/S0304389421031216

Cotton and wood are biopersistent IN HUMAN TISSUE too. It's this kind of study that makes me panic about microplastics less, even *after* that infamous 2024 "microplastics in brains" study [it seems that this year is confirming our worst fears about MPs **and worse**], but it's still possible that microplastics may be unusually likely to lodge in the brain relative to wood/cotton - I don't know.

 

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The ROS production strongly depended on the individual wood types, possibly linked to different natural chemical compounds (e.g., terpenes in softwoods and polyphenolic compounds in hardwoods) (Naarala et al., 2003). However, chemicals used for wood treatment (e.g., chromate compounds) are also discussed as potential drivers of wood dust toxicity (Klein et al., 2001).

The very high bio-persistence of wood likely enhances wood dust toxicity in the lung. Biodegradation of lignin and cellulose requires enzymes found in specialized microorganisms (Slavin et al., 1981, Pérez et al., 2002, Eriksson et al., 1990). There is evidence that wood cellulose fibers persist in rat lungs even a year after exposure and that their estimated half-life is about three years (Muhle et al., 1997).

2.5. Cotton dust

A natural organic airborne pollutant is cotton dust, which is generated during the processing of cotton. It consists mainly of cotton fibers and contains bacteria, fungi, and other plant materials such as cotton stems and leaves (Ayer and Mackison, 1974). Cotton dust exposure in textile mills varies between different processes and mills; total dust concentrations in the range of about 0.1–10 mg m^-3 were observed in a study investigating five textile mills and fourteen different processes (Hammad et al., 1981).

Increased exposure of cotton industry workers to cotton dust is associated with diseases such as asthma, bronchitis, byssinosis (a disease associated with breathing difficulties and chest tightness), and unspecific respiratory problems (Castranova et al., 1996, Dangi and Bhise, 2017). A 15-year follow-up observation showed that the cumulative incidence of byssinosis was 24% among cotton textile workers. In addition, chronic bronchitis and cough were more common and persistent than in the control group (Wang et al., 2003).

Several parameters (Fig. 1E, Table 1) affect the toxicity of cotton dust. The particles in cotton dust are grouped according to their size into ‘trash’ (> 500 µm), ‘dust’ (50–500 µm), ‘micro dust’ (15–50 µm) and ‘breathable dust’ (< 15 µm) (Dangi and Bhise, 2017). Usually, the breathable fraction of cotton dust is linked to adverse effects on animal and human health (Ellakkani et al., 1984).

Mill-collected cotton dust contains a significant fraction of fragmented fibers (Fig. 1E) and large pieces of plant material. The individual cotton dust particles are often irregularly shaped (Goynes et al., 1986).

To date, there have been no investigations of the ζ-potential of breathable cotton dust.

The diseases related to cotton dust exposure are likely not directly caused by the cotton particles but primarily by bacterial endotoxins or residual pesticides adsorbed to the cotton dust, possibly releasing mediators inducing inflammations (Wang et al., 2003, Rylander, 1987, Solbrig and Obendorf, 1985). Consistently, after exposing guinea pigs to breathable cotton dust, all treated animals showed a respiratory response, whereas no response was observed when the animals were exposed to pristine cellulose powder with the same particle size distribution (Ellakkani et al., 1984).

Cotton is likely very bio-persistent, possibly contributing to its chronic toxicity, because it contains a large amount of cellulose. As already mentioned in the section on wood dust, the degradation of cellulose requires enzymes that are only present in specialized microorganisms (Eriksson et al., 1990). In rat and mouse lungs in vivo, cellulose fibers were very persistent and had an estimated half-life of up to 3 years (Muhle et al., 1997, Ilves et al., 2018). Consistently, in lung airway lining fluid and phagolysosomal fluid in vitro, there were no significant signs of degradation of cellulose after up to 9 months of exposure (Stefaniak et al., 2014).

2.6. Hay dust

Exposure to hay dust has been linked to occupational diseases of the lung. Apart from organic debris, pollen and toxins such as endotoxins and mycotoxins are significant contaminants in hay dust (Séguin et al., 2010). The exposure levels to hay dust vary broadly. For example, during the operation of a bedding chopper, the total dust level was found to be in the range of about 10–70 mg m^-3 (Olenchock et al., 1990). Farmer’s increased exposure to hay dust can lead to various respiratory symptoms; most prominently, the inhalation of dust from moldy hay can lead to the so-called farmer’s lung disease (Gregory and Lacey, 1963, Siegel et al., 1991). Farmer’s lung disease is the most common form of extrinsic allergic alveolitis; it is classified into an acute, subacute, and chronic stage (Reboux et al., 2007). Interestingly, also farm animals like dairy cows exposed to hay dust displayed asthma-like symptoms (Siegel et al., 1991).

The physicochemical properties of hay dust (Fig. 1F, Table 1) may contribute to its toxicity. For example, about 95% of hay dust particles are smaller than 5 µm, enabling them to enter the bronchioles upon inhalation (Séguin et al., 2010, O’Connor et al., 2013). Their shape is primarily spherical, although irregularly shaped and rod-like particles also occur in hay dust(O’Connor et al., 2013). It is not known whether their shape affects the hay dust particles’ toxicity. To date, there have been no investigations of the ζ-potential of hay dust particles.

The most prominent parameter affecting hay dust toxicity are microorganisms, endotoxins, and mycotoxins associated with the hay dust (Séguin et al., 2010). Usually, these are the cause of the farmer’s lung disease (Reboux et al., 2007, Cano-Jiménez et al., 2016). Since not the hay itself but inhaled microorganisms cause farmers' lung disease, studies focus on identifying relevant antigens present in the hay dust. The primary treatment of the disease is avoiding the antigens (Cano-Jiménez et al., 2016).

Moreover, like cotton, hay mainly consists of cellulose, likely making it very bio-persistent (Eriksson et al., 1990, Muhle et al., 1997, Ilves et al., 2018, Stefaniak et al., 2014).

2.7. Comparability of non-plastic microparticles and MP

In this section, we focused on different non-plastic microparticles of various materials that potentially determine their physicochemical properties. Some of these non-plastic microparticles are chemically more related to MP than others. For example, wood, cotton, and hay (2.4 Wood dust, 2.5 Cotton dust, 2.6 Hay dust) consist mainly of cellulose, an organic polymer, and are therefore more similar to MP than asbestos or silica, which are inorganic crystals (2.1 Asbestos, 2.2 Silica dust). MP, usually consisting of synthetic polymers, is a diverse group of contaminants with a wide range of physical and chemical properties (Rochman et al., 2019). However, although chemically very different, the physicochemical properties governing the different non-plastic and plastic microparticles’ interactions with cells and tissues might still be comparable (Table 1). Similarities of particles in size, shape, ζ-potential, adsorbed molecules and microorganisms, and bio-persistence may explain similarities in their toxicity and the underlying toxicological mechanisms. Therefore, a comparison of the properties and toxicology of non-plastic particles with MP can improve the understanding of the role of physicochemical properties in MP toxicity.

 

 

Wood cellulose fibers persist in rat lungs after 1 year, higher bio-persistence compared to asbestos. Estimated half-life about 3 years (Muhle et al., 1997)

Edited October 21, 2024 by Alex K Chen