Plastic mulching films, commonly used in agriculture to protect crops and improve growing conditions, can break down over time into tiny plastic fragments called microplastics (MPs). These particles, which range in size from 1 μm to 5 mm, are increasingly found in soils. While previous research has shown that MPs can affect soil organisms like springtails, many of those studies use idealized, uniform plastic particles that don’t reflect the mixed shapes and sizes actually found in the environment.
This study set out to understand whether more realistic MPs—produced by artificially aging real agricultural mulching films—could harm a common soil-dwelling insect, Folsomia candida, also known as the springtail. The researchers tested two types of plastics: a biodegradable plastic made from a starch-PBAT blend, and a more conventional plastic made from LLDPE (linear low-density polyethylene). The springtails were exposed to these particles through the soil over five generations, to observe any potential long-term effects on survival, growth, or reproduction.
The exposure concentrations used reflected what might realistically occur in agricultural soils, ranging from very low to high levels. Across all generations, and at all concentrations, the microplastics did not appear to negatively impact the springtails’ ability to survive or reproduce.
In summary, the findings suggest that, under the tested conditions, microplastics derived from commonly used mulching films may not pose a significant toxic risk to Folsomia candida, even after extended exposure over multiple generations. However, further research may be needed to assess other species and more complex environmental scenarios.
Read the full study here: https://www.sciencedirect.com/science/article/pii/S0048969724052471?via%3Dihub