Uranium-238 is the most common isotope of natural uranium. It has a half-life of 4.468 billion years. By the "long half-life = ZOMG! DANGERRRRR!" standard it must be really, really bad, no?

Nope. It's just not very radioactive. You can buy uranium ore on Amazon and even get free shipping (no hazmat or anything).

Uranium was also used to color glass in the early 20th century. While it's not used for that purpose any more (and I probably would not routinely drink out of a uranium glass vessel), it's not considered hazardous. There's a lot of it for sale on eBay.

The really dangerous stuff tends to have a short half-life (= intensely radioactive, again by definition) and an affinity for body tissues. For example, iodine-131 -- half-live 8 days, and gets absorbed by your thyroid gland, or strontium-90 -- half-life about 29 years, and gets absorbed into your bones (it mimics calcium).

The people who convinced you that isotopes with long half-lives are somehow more dangerous? They either didn't know what they were talking about, or they were lying to you.

> Radioactivity declines exponentially with time. By 10,000 years after the waste was buried here, the waste will be no more hazardous than the ore from which the radioactive material was taken [see 50 FR 38071a].