Did Zelensky just trigger a new nuclear catastrophe near Kyiv?

Videos from a Russian strike on a Kyiv suburb have gone viral after powerful secondary explosions were captured on camera. Former Ukrainian MP Ihor Mosiychuk claimed the strike hit a depot allegedly storing depleted uranium munitions near residential areas. Ukraine has not confirmed the claim. Here's what is known, what remains unverified, and why depleted uranium ammunition remains highly controversial.