University of Michigan researchers discovered nitrile and latex gloves used in labs unintentionally contaminate microplastic samples with stearates, salts chemically similar to plastics. These residues create false positives when measuring airborne or waterborne microplastics, potentially inflating pollution estimates. The study, published in *RSC Analytical Methods*, revealed cleanroom gloves release far fewer stearates, offering a solution to skewed data.

Stearates, used to coat gloves for easier removal from molds, mimic polyethylene microplastics in appearance and structure. In experiments, standard gloves introduced ~2,000 false positives per square millimeter, overwhelming lab results. Researchers emphasized that while contamination exists, the true scale of microplastic pollution remains unclear due to these artifacts. The team developed microscopy and spectroscopy techniques to differentiate stearates from genuine plastics, enabling retroactive analysis of tainted datasets.

The findings underscore the need for specialized equipment in microplastic research. Cleanroom gloves, devoid of stearate coatings, are now recommended for lab work. Lead author Madeline Clough noted, "We’re searching for a needle in a haystack that shouldn’t exist," highlighting the urgency of accurate data. Co-author Anne McNeil called for chemists to lead the field, stressing that plastic ubiquity demands expertise in molecular differentiation.

This breakthrough could reshape environmental science methodologies. By identifying contamination sources, researchers can recalibrate past studies and improve future monitoring. The work, funded by the University of Michigan’s Meet the Moment Research Initiative, demonstrates how technical adjustments—like glove selection—can refine global pollution assessments.