This dataset entails two components: 1) an agricultural soil survey on fields covered with plastic mulch film to determine drivers of microplastic enrichment and identify microplastic types in China, Egypt, India, Sri Lanka, and Vietnam; 2) an inter-laboratory comparison of microplastic quantification and identification across Australia, China, Egypt, India, Sri Lanka, UK, and Vietnam. The data was generated from 2022 to 2025. We recorded the following data: Part 1 - Soil Survey - Site specific metadata on plastic use and farm practices - Environmental data (precipitation, temperature) - Soil data (pH, EC, nutrients, classification, texture) - Microplastic quantification - Microplastic identification - Metadata for each participating laboratory Part 2 - Inter-laboratory standard comparison - Metadata for each participating laboratory - Polymer identification of known polymer standards - Microplastic recovery rates of known reference standard mediums Full details about this dataset can be found at https://doi.org/10.5285/c0407da7-acd0-4f5f-a1f3-5516206ba787