Avoiding and reducing microplastic false positives from dry glove contact.

Area of Science:

• Environmental Science
• Analytical Chemistry
• Materials Science

Background:

• Accurate quantification of microplastics is crucial for understanding and mitigating pollution.
• Standard laboratory gloves (nitrile, latex) can release stearate residues, mimicking microplastic spectra.
• This contamination leads to significant overestimation of microplastic abundance in environmental samples.

Purpose of the Study:

• To identify and quantify microplastic contamination from common laboratory gloves.
• To develop and validate methods for differentiating glove-derived stearate contamination from actual microplastics.
• To provide solutions for correcting existing spectral datasets and improving future microplastic quantification.

Main Methods:

• Analysis of non-volatile residues from nitrile and latex gloves using spectral techniques.
• Comparison of spectral data from glove residues and microplastics.
• Development of data processing workflows to identify and remove stearate spectral signatures.
• Application of workflows to contaminated environmental microplastic datasets.

Main Results:

• Nitrile and latex gloves caused a mean of 2000 false positives per mm² due to stearate contamination.
• Nitrile cleanroom gloves significantly reduced contamination, yielding a mean of 100 false positives per mm².
• Proposed workflows successfully differentiated stearate contamination from microplastics in spectral data.
• The methods effectively reduced microplastic false positives, especially for particles <10 µm.

Conclusions:

• Common laboratory gloves are a significant source of microplastic contamination, inflating abundance estimates.
• Implementing cleanroom gloves and specific spectral analysis workflows is essential for accurate microplastic quantification.
• These findings and methods will improve the reliability of environmental microplastic data and pollution assessments.