DOI: 10.5061/dryad.z612jm6nb
title: Data for: Majority of potable water microplastics are smaller than the 20 µm EU methodology limit for consumable water quality

description: This dataset provides Raman spectral data for the identification of
 microplastics (MPs) in potable water, collected from ten brands of
 polyethylene terephthalate (PET) bottled water and one tap water sample.
 The data includes Raman spectra in .sgd format (SpectraGryph Spectra File)
 for all analyzed particles, facilitating reuse for studies focused on MP
 identification and methodological validation. MP concentrations across the
 samples varied from 19 to 1,154 particles per liter (n/L), corresponding
 to 0.001 to 0.250 micrograms per liter (µg/L). While all bottled water
 samples were stored in PET containers, PET contributed to only a minor
 fraction of the identified MPs in the majority of cases. A total of 14
 different synthetic polymer types were detected, highlighting the diverse
 composition of microplastics in potable water. Notably, 98% of detected
 MPs were smaller than 20 µm, and 94% were below 10 µm, emphasizing the
 critical need to include smaller MPs in potable water assessments and
 regulatory frameworks.
description: In total, n = 660,683 particles were investigated, averaging n =
 55,057 particles per sample (~18 thousand particles per 2x2 mm grid
 subsample), including the procedural blank. All particles measuring ≥1 µm
 in area-equivalent diameter (circular model) were subject to Raman
 analysis. Raman measurements were carried out at 20°C using a Horiba
 LabRAM Soleil (Jobin Yvon, France). The samples were excited at 8% (7.2
 mW) power output with a high stability air-cooled He–Cd 532 nm laser diode
 utilizing a Nikon LV-NUd5 100x objective. The lateral resolution of the
 unpolarized confocal laser beam was on the order of 1 µm. Spectra were
 generated in the range of 200–3400 cm<sup>−1</sup> using a 600
 grooves/cm grating with a 100 µm split. The spectral resolution was on the
 order of 1 cm<sup>−1</sup>. Particles within each mosaic,
 constructed using the LabSpec6 (LS6) SmartView configuration, were
 analyzed using the Particle Finder application V2. LS6 SmartView
 determines the topography (± 50 µm) and saves the focal point of all
 particles on the captured micrograph, enabling the stage to rapidly move
 the relevant particle into focus. The micrograph is converted into an
 8-bit 0–255 greyscale image in which parameters are set by the user to
 visually separate particles from the darker filter substrate. Each
 particle was analyzed for 1 s by 2 accumulations at the above-described
 settings.
description: # Data for: Majority of potable water microplastics are smaller than the
 20 µm EU methodology limit for consumable water quality
 [https://doi.org/10.5061/dryad.z612jm6nb](https://doi.org/10.5061/dryad.z612jm6nb) ## Description of the data and file structure To evaluate the impact of this omission on the total number of detected MPs, we determined MP concentrations down to 1 µm in ten different brands of polyethylene terephthalate (PET) bottled water and one tap water sample using automated Raman microspectroscopy. We found that MP concentrations ranged from 19 to 1,154 (n/L) [0.001 to 0.250 µg/L], and although all the investigated samples of bottled water were stored in PET containers, PET accounted only for a small percentage of identified MPs in most samples. Importantly, 98 and 94% of MPs measured less than 20 and 10 µm in diameter, respectively, demonstrating the importance of small MP inclusion in potable water analyses and regulation. ### Files and variables This folder contains all spectral data related to the study. The suffix #X refers to the number of the sample. Each folder contains three spectral files e.g., Sample1(2) refers to subsample 2 of sample 1, and so on. Each file contains a bundle of thousands of spectra in .sgd format. Here, individual spectra are named 1, 2, 3, and so on, and refer to the individual particles. The morphological information related to the individual particles can be found in the supporting information file S1_Data in .xlxs format. ## Code/software Spectragryph optical spectroscopy software: [https://www.effemm2.de/spectragryph/](https://www.effemm2.de/spectragryph/) ## Access information NA