Data from: Physiological and histopathological effects of polystyrene and polyethylene terephthalate microplastics and their binary mixture in a ground beetle (Blaps polychresta)
Data files
Jul 10, 2026 version files 22.88 KB
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File_SI_Raw_data_updated.xlsx
13.72 KB
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README.md
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Abstract
Microplastic (MP) contamination of soils is increasing, yet mechanistic evidence for mixture toxicity in terrestrial insects remains limited. We investigated the sub-chronic (30-day) dietary effects of polystyrene (PS-MP), polyethylene terephthalate (PET-MP), and their binary mixture (1% PS + 1% PET; total 2% w/w) on the ground beetle Blaps polychresta. Endpoints included defecation rate, digestive enzyme activities (amylase and protease), oxidative stress biomarkers (ROS, CAT, SOD), and histopathological alterations in the midgut and testis. Survival was unaffected; however, PS and PET individually reduced defecation rate, whereas the mixture did not further exacerbate gut motility impairment. All treatments significantly altered digestive physiology, with increased amylase and reduced protease activity, the strongest imbalance occurring in the mixture group. ROS levels were elevated in both midgut and testicular tissues, accompanied by significant upregulation of CAT and SOD, indicating oxidative stress–mediated responses. Histological investigation revealed epithelial disruption and muscle disorganization in the midgut, and degeneration of testicular follicles, vacuolization, pyknosis of spermatocytes, and reduced follicular integrity. Trypan blue staining confirmed increased cellular damage in the testes following MP exposure. Testicular follicle diameter decreased in PS- and PET-exposed beetles, indicating impaired spermatogenesis. Overall, chronic ingestion of PS and PET disrupts digestive and male reproductive physiology through oxidative stress–linked mechanisms, with mixture exposure intensifying several biochemical and histopathological effects. These findings highlight the importance of incorporating polymer interactions into terrestrial insect risk assessments.
Dataset DOI: 10.5061/dryad.tht76hff8
Description of the data and file structure
The dataset was generated from a controlled laboratory experiment designed to evaluate the physiological, biochemical, and histopathological effects of microplastic exposure in the ground beetle Blaps polychresta. Adult male beetles were collected from Tanta University, Egypt, and maintained under standardized laboratory conditions before being exposed for 30 days to diets containing polystyrene (PS) microplastics, polyethylene terephthalate (PET) microplastics, or a binary mixture of both polymers (1% PS + 1% PET; total concentration 2% w/w). A control group was maintained under identical conditions without microplastic exposure.
The experiment consisted of four treatment groups (Control, PS, PET, and PS+PET, represented as "Mix" in data files), each represented by three independent biological replicates. Each replicate contained 30 beetles housed in separate experimental units. Microplastics were generated from commercial plastic products, micronized, sieved to obtain particles within the microplastic size range, and chemically verified using ATR-FTIR spectroscopy.
Data collected included survival, defecation rate, digestive enzyme activities (amylase and protease), oxidative stress biomarkers (reactive oxygen species, catalase, and superoxide dismutase) measured in both midgut and testicular tissues, and multiple histopathological endpoints. Histological analyses assessed structural alterations in the midgut and testes, while trypan blue staining and ImageJ-based image analysis were used to quantify testicular cell damage and follicle diameter. Statistical analyses included one-way ANOVA and factorial two-way ANOVA to evaluate both individual polymer effects and interactions between PS and PET exposure. The dataset provides mechanistic information on digestive dysfunction, oxidative stress, and reproductive toxicity associated with environmentally relevant microplastic contamination in terrestrial ecosystems.
Files and variables
File: File_SI_Raw_data_updated.xlsx
Description:
Raw and processed data collected from a 30-day laboratory exposure experiment investigating the effects of polystyrene (PS) microplastics, polyethylene terephthalate (PET) microplastics, and their binary mixture on the ground beetle Blaps polychresta.
Sheet 1: Defecation
| Variable | Description | Unit |
|---|---|---|
| Treatment | Experimental treatment | - |
| Fecal pellet | Average fecal pellets produced per beetle per day | pellets beetle⁻¹ day⁻¹ |
Sheet 2: Digestive Enzymes
| Variable | Description | Unit |
|---|---|---|
| Treatment | Experimental treatment | - |
| Amylase | Midgut α-amylase activity | ng mL⁻¹ |
| Protease | Midgut protease activity | ng mL⁻¹ |
Sheet 3: Midgut Oxidative Stress Biomarkers
| Variable | Description | Unit |
|---|---|---|
| Treatment | Experimental treatment | - |
| ROS midgut | Reactive oxygen species level in midgut tissue | nmol mg⁻¹ tissue |
| CAT midgut | Catalase activity in midgut tissue | U mg⁻¹ |
| SOD midgut | Superoxide dismutase activity in midgut tissue | U mg⁻¹ |
Sheet 4: Testis Oxidative Stress Biomarkers
| Variable | Description | Unit |
|---|---|---|
| Treatment | Experimental treatment | - |
| ROS testis | Reactive oxygen species level in testicular tissue | nmol mg⁻¹ tissue |
| CAT testis | Catalase activity in testicular tissue | U mg⁻¹ |
| SOD testis | Superoxide dismutase activity in testicular tissue | U mg⁻¹ |
Sheet 5: Histopathology and Cellular Damage
| Variable | Description | Unit |
|---|---|---|
| Treatment | Experimental treatment | - |
| Intensity | Integrated staining intensity of trypan blue measured using ImageJ | arbitrary units (A.U.) |
| Follicle diameter | Maximum transverse diameter of testicular follicles | µm |
Abbreviations
| Abbreviation | Definition |
|---|---|
| MP | Microplastic |
| PS | Polystyrene microplastic |
| PET | Polyethylene terephthalate microplastic |
| PS+PET | Binary mixture of polystyrene and polyethylene terephthalate microplastics |
| ROS | Reactive oxygen species |
| CAT | Catalase |
| SOD | Superoxide dismutase |
| PBS | Phosphate-buffered saline |
| FTIR | Fourier-transform infrared spectroscopy |
| ImageJ | Open-source image analysis software |
Missing values
No data points were excluded from the statistical analyses.
Missing values, if present in the dataset, are indicated as:
NA = Not Available
Blank cells were not used to represent missing values.
Code/software
The dataset is provided in Microsoft Excel (.xlsx) format and can be accessed using a range of free and open-source software packages. Recommended software includes:
- LibreOffice Calc (version 7.0 or later)
- Apache OpenOffice Calc (version 4.1 or later)
- R (version 4.3 or later) with the packages:
- readxl
- tidyverse
- ggplot2
- dplyr
- Python (version 3.10 or later) with the packages:
- pandas
- numpy
- matplotlib
- scipy
No proprietary software is required to view or analyze the data, although Microsoft Excel (version 2016 or later) can also be used.
Workflow
The raw data were recorded in Microsoft Excel spreadsheets and organized by experimental endpoint. Data files contain measurements from laboratory exposure experiments evaluating the effects of polystyrene (PS) microplastics, polyethylene terephthalate (PET) microplastics, and their binary mixture on the ground beetle Blaps polychresta.
Statistical analyses were performed using GraphPad Prism version 8.0.1 (GraphPad Software, La Jolla, California, USA). The analytical workflow included:
- Data organization and quality checking.
- Assessment of normality and homogeneity of variance.
- One-way ANOVA followed by post hoc multiple-comparison tests.
- Two-way factorial ANOVA to evaluate the independent and interactive effects of PS and PET exposure.
- Generation of figures and summary statistics.
Microscopy images were processed and analyzed using ImageJ (National Institutes of Health, USA; version 1.54 or later). ImageJ was used to quantify trypan blue staining intensity and measure testicular follicle diameter after calibration with image scale bars.
No custom code, scripts, macros, or software packages were developed specifically for this study. All analyses were conducted using the software packages listed above, and the published results can be reproduced directly from the supplied datasets.
Access information
The dataset associated with this study is publicly available through the repository in which this record is deposited.
The data were generated specifically for this study and are not derived from any external datasets. Therefore, no third-party data sources, licenses, or access restrictions apply.
Additional information regarding experimental procedures, data collection, and statistical analyses can be found in the associated research article:
ElKholy S., Elfarnawany A., and Al Naggar Y. Physiological and Histopathological Effects of Polystyrene and Polyethylene Terephthalate Microplastics and Their Binary Mixture in a Ground Beetle (Blaps polychresta).