FTIR hyperspectral image of microplastics extracted from a soil sample

General description

The upload presents an uFTIR hyperspectral image of microplastics extracted form a soil sample taken with an Agilent Cary 620 FTIR spectrometer. The image was used to perform the benchmark test of an R package: uFTIR (https://CRAN.R-project.org/package=uFTIR).

Microplastic extraction

The sample comes from a previous study (Corradini et al, 2019) from which we take a sample testing 1.4 plastics particles per gram of soil by Zhang et al (2018) method reported in (Corradini et al, 2021a). The soil sample was suspended in ZnCl₂, stirred, centrifuged, and vacuum-filtered three times. At the end of the preparation process, a filter (Whatman(R) Anodisc Inorganic Membranes) that collected all buoyant particles was ready for the image acquisition.

Image acquisition

The \(\mu\)FTIR analysis was performed in transmission mode with a spectral resolution of 8 cm^-1 through a spectral range of 3500 - 1300 cm^-1 and 8 co-added scans. Data was recorded in absorbance (%). The microscope magnification was x4 with a pixel size resolution of 20.6 \(\mu\)m. The image comprises 64 single shots and 12Gb.

Accompanying data

We included a second folder that holds 4 images of 4 films made of 4 different plastic polymers that we took under the same conditions. We used this data to validate the accuracy of the software. The polymer films correspond to  one polyethylene bag, two plastic cups ---one made of polypropylene and the other made of polystyrene---, and a polystyrene standard film (VARIAN P/N 883-9120).

Further reading

For a closer description of the soil sample and sample preparation see Corradini et al (2021a). For a detailed description of the software see (Corradini et al, 2021b), and visit the CodeOcean computer capsule at https://doi.org/10.24433/CO.5579643.v1. The software itself is available at R-CRAN repository (https://CRAN.R-project.org/package=uFTIR).

If you reuse this image please cite

Corradini, F, N Berriot, E Huerta-Lwanga, V Geissen. 2021. uFTIR: an R package to process hyperspectral images of environmental samples captured with \(\mu\)FTIR microscopes. SoftwareX,

---

References

Corradini et al. 2021a. 2021. Microplastics occurrence and frequency in soils under different land uses on a regional scale. Science of the Total Environment, 752, 141917. 10.1016/j.scitotenv.2020.141917

Corradini et al. 2021b. uFTIR: an R package to process hyperspectral images of environmental samples captured with \(\mu\)FTIR microscopes. SoftwareX, 16, 100857. 10.1016/j.softx.2021.100857

Corradini et al. 2019. Usefulness of an opportunistic data analysis approach to evaluate if environmental regulations aim at relevant applications. Geoderma, 351, 261-269. 10.1016/j.geoderma.2019.05.007

Zhang et al. 2018. A simple method for the extraction and identification of light density microplastics from soil. Science of the Total Environment, 616-617, 1056-1065. 10.1016/j.scitotenv.2017.10.213