As of 2021, nuclear powerplant accidents killed less than 2 people per year since 1970s. As of 2018, nuclear powerplants produced 10% of energy.
WHO estimates that climate change causes 150000 deaths per year.
Fossil-fuels powerplants produce surprisingly low air pollution due to all required by law filters, technologies etc.
(Source: it's discussed in the book The Uninhabitable Earth, although I don't have a copy to hand so can't find the exact citations.)
Very minor cognitive impairment levels can happen in worst-case scenario in 2100 and assuming current increase of CO2 concentration over time, it shouldn't happen before 2300.