metacheck comes with a built-in data frame called retractionwatch. We update it regularly, but you can use this function to download the newest version. The download is >50MB, but this function will summarise the information into a smaller version (~0.5 MB) and delete the original file.
Details
The data come from the Crossref Labs API. Crossref is retiring that API; when it cannot be reached, Crossref's copy on GitLab (https://gitlab.com/crossref/retraction-watch-data) is used.
