Choosing regulated cannabis means you get products tested for things like mould...

https://angelowlnv711.yousher.com/why-is-guessing-thc-and-cbd-levels-a-problem-for-patients

Choosing regulated cannabis means you get products tested for things like mould and pesticides, so you know what’s inside and can use safely. Unregulated cannabis doesn’t guarantee this, so potency can vary widely and contaminants may be present