The "never made it to WHO statistics" as the difference in cancer incidence rates and other problems after Chernobyl are so small that they are hard to distinguish from the background noise. A lot of work has gone into trying to document the actual effects, but the reality is that while there were initial large spikes in e.g. thyroid cancer among children, the cancers that spiked are ones with very high survival rates. The WHO estimates were initially very high, but keep being adjusted down because every year that goes is another year without a spike in deaths above expected levels.

The breakup of the Soviet Union caused much larger scale effects on life expectancy.