I think you're referring to nitrosamines, and according to Robert Nilsson who is a professor at Stockholm University, there is "no proof of correlation between snus and cancer"[1] and indeed in 2002, the warning labels had to be changed,[2] and today "only" reads (my translation): "This tobacco product harms your health and is addictive", which is a far cry from the EU mandated warning on cigarettes that goes more like "Smoking kills", with some variants.

[1]: https://www.dagensmedicin.se/artiklar/2012/05/26/snus-bor-in...

[2]: https://www.snusbolaget.se/snusjournalen/snus-och-halsa-del-...