Pollution Particles Hitch Ride on Red Blood Cells, Putting Organs at Risk

According to a study published on October 2, 2025, tiny air pollution particles are hitching a ride on red blood cells, enabling them to travel throughout the body and potentially cause harm to major organs. Researchers from Queen Mary University of London recruited 12 adults to spend an hour next to a busy London street, finding that the participants had two to three times more pollution particles attached to their red blood cells after the exposure.

The study provides the first clear evidence of how these microscopic particles, produced by motor vehicles and industrial emissions, are able to infiltrate the body's vital systems. "We're finding more and more evidence that air pollution particles are making their way into many different organs of the body and now we have clear evidence of how that could be happening," said lead researcher Dr. Jonathan Grigg.

To confirm the findings, the researchers also exposed human and mouse red blood cells to diesel exhaust in the lab, observing the same phenomenon of particles sticking to the cells. Analysis showed the particles contained metals like iron, copper, and chromium from car emissions, as well as materials from brake and tire wear.

Encouragingly, the study also found that wearing a face mask designed to filter out particle pollution can prevent these particles from reaching the bloodstream. "We were surprised to find how well an FFP2 face mask prevents these very tiny particles from reaching and attaching to blood cells," Grigg said.