Microplastics – tiny pieces of plastic less than 5mm in diameter – have been found in human blood for the first time. Scientists in the Netherlands took blood samples from 22 healthy adult donors and analyzed them for particles as small as 700 nm. The researchers found that 17 out of the 22 volunteers (77.2%) had microplastics in their blood – a finding described as ‘extremely concerning’. Microplastics have been found in the brain, gut, the placenta of unborn babies, and the feces of adults and infants, but never before from blood samples.