We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microplastics in groundwater: evaluation of sampling methods
Summary
Researchers evaluated three groundwater sampling techniques — peristaltic pump, bladder pump, and stainless-steel bailer — for their potential to contaminate samples with microplastics, conducting laboratory controls by passing MP-free deionized water through each device and filtering through 63 micron stainless-steel sieves to assess method-specific contamination.
There is no standardized methodology for sampling microplastics (MPs) in aquifers, highlighting the need for research to develop procedures that ensure the collection of representative samples free from interference. This study evaluated groundwater sampling techniques (peristaltic pump, bladder pump, and stainless-steel bailer) and their influences on sample contamination by MPs. Laboratory equipment controls were conducted, involving the passage of MP-free deionized water through the equipments, followed by concentration with a stainless-steel sieve (63 μm mesh) and filtration on mixed cellulose ester membrane filters. The particles were analyzed under a stereomicroscope for morphological characterization (size, shape, and color). MPs were detected in all controls, with peristaltic pumps exhibiting the highest count (40 MPs), followed by bladder pumps (25 MPs) and stainless-steel bailers (23 MPs), with fibers in transparent and blue colors. The higher presence of MPs in peristaltic and bladder pumps is possibly due to plastic materials in their composition, while MPs in the stainless-steel bailer suggest that previous equipment cleanliness is crucial. The bailer was chosen for groundwater sampling from the Bauru Aquifer System, São Paulo, Brazil. Five liters of groundwater were sampled along with field controls. A significant number of MPs were detected in the groundwater, consisting of fibers (transparent, blue, black, and red), and blue fragments. In the controls, the quantities were significant relative to the total observed in the groundwater sample. However, the field control simulated the time that the sieve remained exposed to the atmosphere during sampling, making it impossible to quantify the MPs resulting from atmospheric deposition. Therefore, equipment cleaning and atmospheric particle deposition are crucial aspects of MPs sampling in groundwater as they greatly influence sample contamination. Further studies are needed to establish a standard for sampling MPs in groundwater, allowing for interference-free samples and representative collection at flow rates suitable for these analyses. Also see: https://micro2024.sciencesconf.org/559055/document