Rapid Detection of Nanoplastic Contamination in Plastic Labware by Dynamic Light Scattering Highlights Variations in Experimental Precision

Nanoplastics (NPs) are emerging contaminants of environmental
concern,
raising significant alarms due to their prevalence and potential health
risks. Unlike larger microplastics, NPs are challenging to detect
due to their nanodimensions and the reliance on labor-intensive methods
such as nanoparticle tracking analysis (NTA) or scanning electron
microscopy (SEM). This underscores the urgent need for rapid and accessible
detection methods. To address these challenges, we employed dynamic
light scattering (DLS), a widely used technique for measuring nanoparticle
sizes, to rapidly quantify NP concentrations and sizes. Using DLS,
we demonstrated the prevalence of NPs originating from laboratory-based
plastic consumables such as microcentrifuge tubes, cryovials, and
Petri dishes. Notably, routine actions, including pipet-tip scraping
against plastic labware during sample handling, can introduce NPs
into solutions. Moreover, physical or chemical procedures, especially
sonication and liquid nitrogen treatment, further exacerbate the NP
release. This interfered with experimental outcomes, including skewing
of DNA and iron nanoparticle concentrations. Our material analysis
revealed that the NPs were made of polystyrene and polypropylene,
which correlated to manufacturers’ product details. Hence,
our study highlights an under-recognized NP source that compromises
research integrity while contributing to global NP pollution, thus
emphasizing the need for sustainable laboratory practices and robust
contamination control.