I always say no because receipts have been shown to commonly contain BPA and other cancer-causing/endocrine-disrupting chemicals that can be absorbed through your skin. The data seems to be mixed on whether or not the dermal uptake is significant enough to pose a threat, but I just don’t want to take the chance.

If you have to have a receipt, try to touch it for the least amount of time possible, avoid touching the printed side, and keep it in a container or Ziploc bag in your main bag or somewhere else.

https://www.snopes.com/fact-check/receipt-paper-harmful/
https://www.ecocenter.org/our-work/healthy-stuff-lab/reports/receipt-deceit-toxic-chemicals-receipt-paper/test-results
https://www.sciencedirect.com/science/article/pii/S0160412020319863
https://pubmed.ncbi.nlm.nih.gov/33313651/
https://ehp.niehs.nih.gov/doi/10.1289/isee.2013.S-2-37-02

Repos are archived by the maintainer, but I find these really helpful resources:

https://github.com/dylanaraps/pure-bash-bible https://github.com/dylanaraps/pure-sh-bible