For the first time, microplastics have been detected in human blood. The discovery by a team of Dutch researchers is described in the study just published in Environment International. And it reveals the finding of plastic in the blood of 77 percent of research participants.
Microplastics in blood, the way to biomonitoring
Blood makes up 6-7% of body weight in humans. It irrigates the body’s organs and is the transport route for oxygen, nutrients, and potentially even plastic particles to other tissues and organs. It is therefore an ideal matrix for conducting biomonitoring of plastic particles in humans.
The purpose of the Dutch study was to define a method useful for detecting and measuring only plastic particles in human blood, eliminating interference from other types of particles.
The plastics sought
Scientists looked for five of the most common polymers in plastic materials:
– polyethylene (PE), used in the manufacture of lids and food containers, such as water bottles that release chemicals to the water they contain, which we have reported on, (2)
– polypropylene (PP), a thermoplastic polymer widely used in the production of food containers,
– polyethylene terephthalate (PET), the most common use is in water and beverage bottling, again with the risk of chemical migration into the food, as we have seen, (3)
– materials containing polymerized styrene (PS), such as polystyrene, expanded polystyrene (EPS) and acrylonitrile butadiene styrene (ABS),
– poly(methylmethylmethacrylate) (PMMA), less common in consumption but selected by researchers because it is used in various applications within the human body (including synthetic fillers in aesthetic medicine).
These substances are found in food contact materials (MOCAs), textiles, and many everyday consumer products, including those ‘personal care products that could be ingested (e.g., PE in toothpaste, PET in lip gloss), dental polymers, drug delivery polymer nanoparticles (e.g., PMMA, PS), tattoo ink residues (e.g., acrylonitrile-butadiene styrene particles)‘, warn the study authors.
As a result, these polymers are also among the most widespread environmental plastic pollutants, found in air, water and food, uncontrollable routes of exposure (by ingestion and inhalation). (4)
Microplastics in the blood of 77% of participants
The finding of microplastics is confirmed in 77 percent of the participants, that is, in 17 of the 22 donors, in various concentrations, with an average of 1.6 µg total plastic particles/ml blood. Up to three different types of polymers were measured in a single sample.
The polymers most commonly found in the blood analyzed are.
– PET, detected in 50% of the sample (11 donors),
– PS, 36% (8 individuals),
– PE, 23% (5 people),
– PMMA, 5% (in a single donor).
The top three most present polymers are also those detected in the highest concentrations. The maximum levels are 2.4 µg/ml blood for PET, 4.8 µg/ml for PS and 7.1 µg/ml for PE.
The only polymer absent from the analysis is PP.
Public health, lack of data
Dutch study adds new piece to inspire public health policies. Currently, in fact, data on toxicological risk and human exposure to microplastics are considered insufficient for a human health risk assessment.
The scientific community, meanwhile, continues to produce evidence of exposure that is now out of control. Microplastics have been found in human feces and placenta. Animal experiments confirm.
‘In a study of acute lung exposure to nanopolystyrene spheres (20 nm) in rats, translocation of plastic particles into placental and fetal tissues was demonstrated. Bioaccumulation of small microparticles of polystyrene in the liver, kidney and intestine was observed after oral administration in mice in vivo’, report the study authors, who also report how in another mammalian study there is evidence that ‘nanometer-sized polymer vectors are able to deliver drugs across the blood-brain barrier.’
The conclusions
From animals to humans, the present study ‘supports the hypothesis that human exposure to plastic particles determines the uptake of the particles into the bloodstream.
This indicates that at least some of the plastic particles that humans come into contact with may be bioavailable and that The rate of elimination, for example, through the biliary tract, kidneys, or transfer and deposition in organs Is slower than the rate of absorption in the blood‘, the researchers conclude.
Marta Strinati
Notes
(1) Heather A. Leslie, Martin J. M. van Velzen, Sicco H. Brandsma, Dick Vethaak, Juan J. Garcia-Vallejo, Marja H. Lamoree. Discovery and quantification of plastic particle pollution in human blood. Environment International, 2022. https://doi.org/10.1016/j.envint.2022.107199.
(2) Marta Strinati. Plastic water bottles, high levels of chemical migration. GIFT(Great Italian Food Trade), 12.2.22 https://www.greatitalianfoodtrade.it/imballaggi-e-moca/borracce-in-plastica-alti-livelli-di-migrazione-di-sostanze-chimiche
(3) Marta Strinati. Recycled PET, more chemicals migrate from bottles to beverages. GIFT(Great Italian Food Trade), 3/21/22. https://www.%C3%
(4) On the pathways of human exposure to microplastics, see:
Dario Dongo, Microplastics away in the wind, contaminated even the air. GIFT(Great Italian Food Trade), 9/24/19. https://www.greatitalianfoodtrade.it/sicurezza/microplastiche-via-col-vento-contaminata-anche-l-aria
Marta Strinati, Microplastics inside fruits and vegetables. The Italian study. GIFT(Great Italian Food Trade), 6/21/20. https://www.greatitalianfoodtrade.it/sicurezza/microplastiche-dentro-la-frutta-e-la-verdura-lo-studio-italiano
Marta Strinati, Microplastics in drinking water, WHO calls for risk assessment. GIFT(Great Italian Food Trade), 8/22/19, https://www.greatitalianfoodtrade.it/sicurezza/microplastiche-nell-acqua-potabile-l-oms-chiede-valutazione-dei-rischi
Dario Dongo, Ylenia Patti Giammello, Plastics and microplastics in the Mediterranean, a cultural challenge. GIFT(Great Italian Food Trade), 8/30/19. https://www.greatitalianfoodtrade.it/progresso/plastiche-e-microplastiche-nel-mediterraneo-una-sfida-culturale
Professional journalist since January 1995, he has worked for newspapers (Il Messaggero, Paese Sera, La Stampa) and periodicals (NumeroUno, Il Salvagente). She is the author of journalistic surveys on food, she has published the book "Reading labels to know what we eat".
