Detecting microplastics in human blood

• A study by researchers from The Netherlands has examined blood samples of 22 persons, all anonymous donors and healthy adults, and found plastic particles in 17 of them.
• The size of the particles that the group looked for was as small as about 700 nanometres.
• This is really small and it remains to be seen if there is a danger of such particles crossing the blood cell walls and affecting the organs.

What are microplastics?

• Microplastics are tiny bits of various types of plastic found in the environment.
• The name is used to differentiate them from “macroplastics” such as bottles and bags made of plastic.
• There is no universal agreement on the size that fits.

What were the plastics that the study looked for in the blood samples?

• The study looked at the most commonly used plastic polymers.
• These were polyethylene tetraphthalate (PET), polyethylene (used in making plastic carry bags), polymers of styrene (used in food packaging), poly (methyl methylacrylate) and poly propylene.
• They found a presence of the first four types.

How was the study conducted?

• In the study, blood from 22 adult healthy volunteers was collected anonymously, protected from contamination, and then analysed for its plastic content.
• The size of the bore in the needle served to filter out microplastics of a size greater than desired.
• This was compared against suitable blanks to rule out a pre-existing plastic presence in the background.

What are the key results of this study?

• The study found that 77% of tested people carried various amounts of microplastics above the limit of quantification.
• They found in each donor, on average, 1.6 micrograms of plastic particles per millilitre of the blood sample.
• It is a helpful starting point for the further development of analytical studies for human matrices research.

Significance of the study

• Making a human health risk assessment in relation to plastic particles is not easy due to the lack of data on the exposure of people to plastics.
• Hence studies like this one are important.
• Validated methods to detect the tiny (trace) amounts of extremely small-sized (less than 10 micrometre) plastic particles are lacking.
• Hence this study, which builds up methods to check the same, is important.
• Owing to the small size of the participants, the study results cannot be taken as such to mould policy etc, but the method and demonstration are useful in explaining that such a possibility of finding microplastics in the blood exists.

Does the presence of microplastics in blood have health impacts?

• It is not yet clear if these microplastics can cross over from the bloodstream to deposit in organs and cause diseases.
• The study points out that the human placenta has shown to be permeable to tiny particles of polystyrene.
• Experiments on rats where their lungs were exposed to polystyrene spheres led to translocation of the nanoparticles to the placental and foetal tissue.
• Oral administration of microplastics in rats led to the accumulation of these in the liver, kidney and gut.
• Further studies need to be carried out to really assess the impact of plastics on humans.