What are the tiny black dots found in human blood samples?

The tiny black dots found in human blood samples are particles of carbon and other chemicals from the incomplete burning of fuel, known as PM 2.5, which are a component of air pollution.

How much air pollution could be transported in the blood?

Researchers estimate that up to 80 million red blood cells could be transporting pollution around an adult's body.

Where do air pollution particles go in the body?

Scientists believe that particles of pollution may wiggle through the lining of blood vessels and lodge in various organs throughout the body.

Home / Health / Microscopic Black Dots in Your Blood: Air Pollution's Toll

Microscopic Black Dots in Your Blood: Air Pollution's Toll

7 Feb

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Summary

Tiny black particles from air pollution were seen stuck to red blood cells.
Researchers estimate 80 million red blood cells could transport pollution.
Pollution deposits have been found in placentas and may lodge in organs.

Microscopic Black Dots in Your Blood: Air Pollution's Toll

A groundbreaking experiment has revealed the presence of air pollution directly within human bloodstreams. Tiny black particles, identified as carbon from incomplete fuel combustion (PM 2.5), were found attached to red blood cells after volunteers spent just 10 minutes near busy London traffic. Researchers estimate that this could amount to 80 million red blood cells carrying pollution throughout the body.

While levels in the blood decrease after two hours of clean air, the particles' ultimate destination is a major concern. Scientists hypothesize they may pass through blood vessel linings and accumulate in organs, potentially explaining links between air pollution and health issues beyond the lungs, including in the brain and developing fetuses. Black carbon deposits have been found in placentas, suggesting widespread distribution.