Scientists shocked to find lab gloves may be skewing microplastics data

 A University of Michigan study suggests that the nitrile and latex gloves scientists commonly use could be causing microplastics levels to appear higher than they actually are.

Researchers found that these gloves can unintentionally transfer particles onto lab tools used to analyze air, water, and other environmental samples. The contamination comes from stearates, which are not plastics but can closely resemble them during testing. Because of this, scientists may be detecting particles that are not true microplastics. To reduce this issue, U-M researchers Madeline Clough and Anne McNeil recommend using cleanroom gloves, which release far fewer particles.Stearates are salt-based, soap-like substances added to disposable gloves to help them separate easily from molds during manufacturing. However, their chemical similarity to certain plastics makes them difficult to distinguish in lab analyses, increasing the risk of false positives when studying microplastic pollution.

The researchers emphasize that this does not mean microplastics are not a real problem.

"We may be overestimating microplastics, but there should be none," said McNeil, senior author of the study and U-M professor of chemistry, macromolecular science and engineering, and the Program in the Environment. "There's still a lot out there, and that's the problem."

Clough added, "As microplastic researchers looking for microplastics in the environment, we're searching for the needle in the haystack, but there really shouldn't be a needle to begin with."

The research, led by Clough, a recent doctoral graduate, was published in RSC Analytical Methods and supported by the U-M College of Literature, Science, and the Arts' Meet the Moment Research Initiative.

Unexpected Source Behind Inflated Results

The discovery began during a collaborative project examining airborne microplastics in Michigan. The effort involved researchers from multiple U-M departments, including Chemistry, Statistics, and Climate and Space Sciences Engineering. Clough and McNeil worked with collaborators such as chemistry professor Andy Ault and graduate students Rebecca Parham and Abbygail Ayala to collect air samples.

To capture particles, the team used air samplers equipped with metal surfaces that collect material from the atmosphere. These samples were then analyzed using light-based spectroscopy to identify the types of particles present.

While preparing the sampling surfaces, Clough followed standard practice and wore nitrile gloves. However, when she reviewed the results, the number of detected microplastics was thousands of times higher than expected.

Source: ScienceDaily