But marijuana is notoriously expensive and difficult to obtain in Australia; this has resulted in the flourishing of the black market over the last few years. There are many risks from buying weed from the black market: patients have no guarantee what’s in the herb, and it can also contain contaminants that can make illnesses worse. The unregulated products sold in Australia’s black market are no different from those in the US black market: unidentified ratio of THC and CBD, as well as other substances that we have no idea about.