Almost all of the 50-100,000 civilians killed as a consequence of the Gulf War were killed by Saddam Hussein putting down an insurgency. (Direct civilian losses by the hands of the invading force were less than 4,000.) That the U.S. gave the impression they would support an insurgency and then left those people to be slaughtered by Hussein became a not insignificant piece of moral propaganda used by Dick Cheney, Ahmed Chalabi (leader of the pseudo-government in exile), and others to justify the Iraq War.
IOW, the talking point that those deaths were the fault of the U.S. invasion was ultimately used to have another go, resulting in even more deaths. We should be really careful about making moral equivalencies. Yes, in a very real sense the Gulf War was a but-for cause, and being mindful of how such campaigns can upset regional stability to the detriment (in absolute terms) of civilian life is important, but that's definitely not the same thing as having killed those people directly.
EDIT: If you were referring to the carcinogenic effects of depleted uranium, the evidence has been extremely equivocal even to this day. Unsurprising given the insane confounders, such as all the other unchecked chemicals used in the environment in such areas, not to mention the after effects of actual physical violence of a particular war, as well as ongoing violence populations typically suffer under autocratic regimes (including actual chemical weapons repeatedly deployed by Hussein). Plus there's the general anti-nuclear hysteria one must account for, which creates a selection bias in whom and what is studied by those with an axe to grind. All of which is to suggest a very small epidemiological effect at best. In violence ravaged areas the least of anybody's worries, and certainly nothing that could even remotely rise to the same level of concern as unleashing a military on a population, using any kind of weaponry. Anybody seriously concerned about depleted uranium in Iraq should probably steer clear of Ukrainian agricultural products for quite awhile given the nasty chemicals being currently dispersed across Ukrainian fields from weaponry and fires. But we both know that's a mostly irrational (i.e. disproportionate) concern even if theoretically plausible.