Microplastics Detected in Olfactory Bulb of 8 Out of 15 Human Cadavers, Study Finds

Scientists in Brazil detected microplastics in the olfactory bulb tissue of eight out of 15 human cadavers, according to a study published September 16, 2024, in the journal JAMA Network Open. The 15 cadavers came from individuals who died between the ages of 33 and 100. Researchers identified a total of 16 plastic fibers and particles across the samples.

4 micrometers. The smallest particles were slimmer than the diameter of a human red blood cell, which measures about 8 micrometers. The most common plastic type identified was polypropylene.

Other plastics found included polyamide, nylon, and polyethylene vinyl acetate. Thais Mauad, associate professor of pathology at the University of São Paulo Medical School in Brazil and lead study author, said previous research had shown air pollution particles reach the brain through the olfactory bulb.

“Previous studies in humans and animals have shown that air pollution reaches the brain, and that particles have been found in the olfactory bulb, which is why we think the olfactory bulb is probably one of the first points for microplastics to reach the brain,” she said.

Mauad also noted widespread indoor exposure. “Propylene is everywhere, in furniture, rugs, clothes,” she said. ” Matthew Campen, a toxicologist at the University of New Mexico who has studied microplastics in the brain, said the findings were expected.

“The nose is a major point of defense to keep particles and dust out of the lungs,” he wrote. ” Campen added that the samples likely contained many nanoplastics, which range from 1 to 1,000 nanometers in size. 5 nanometers thick.

One micrometer equals 1,000 nanometers. Mounting research over the last few years has found microplastics in nearly every organ in the body, as well as in the bloodstream and in plaque that clogs arteries. A recent study showed that exposure to microplastics through drinking water over three weeks caused cognitive changes in mouse brains and that the particles crossed the blood-brain barrier.