A University of Michigan researcher stumbled upon a crucial caveat for every study of microplastics that has been scaring us for years now. Lab gloves may have skewed the data in the research. Chemistry grad student Madeline Clough discovered that residue from latex or nitrile gloves may be unintentionally contaminating lab equipment used to measure microplastics in the air and water, thus inflating estimates of the pollution. She knew the numbers were “many thousands of times greater” than what she expected. That led to a wild goose chase of trying to figure out where the contamination was coming from, and it wasn’t long before Clough decided to look at the gloves the researchers were wearing. Particles called stearates — a kind of salt or soap — were found to be the culprits. Manufacturers coat disposable gloves with these particles to make them easier to peel from the molds used to form them. They are chemically similar at a structural level to microplastics and look nearly identical, which can lead to false positives or inflated numbers of microplastic pollution. Researchers designed a new experiment to figure out how widespread the problem is, testing seven different kinds of gloves. They found that, on average, the gloves imparted about 2,000 false positives per millimeter squared area. The team began to warn other researchers to wear cleanroom gloves and take other precautions so as not to skew the data and unknowingly make the microplastics outlook even more alarming.
