Ok, here is a topic I know quite a bit about. Household mains in Australia, although 240V (the more dangerous kind) is a vanishingly small proportion of electrical deaths:
https://www.erac.gov.au>95% of deaths are from distribution infrastructure, only a tiny percent are from interaction with 240V.
We do have international standards for electrical hazards like the Test and Measurement standard 61010. That has within it various graphs for "acceptable" exposures:
maximum single fault duration (dry conditions): 110V AC 200ms, 240V AC 40ms, 5x shorter exposure
normal (non fault) accessible capacitance: 110V DC 4uF 24mJ, 240V DC 1.5uF 43mJ, higher energy permissible for higher voltage!
It is not always a clear cut more = worse, or a steady relationship. How about:
"Effects of current on human beings and livestock" IEC 60479
Median body impedance, hand to hand (dry): 100V 1725ohm 60mA, 225V 1225ohm 200mA
Its those (median) currents where the difference lies. 110V is unlikely to produce heart or breathing arrest even with a sustained exposure, while 240V is almost certainly going to interrupt essential body functions unless the exposure is limited in duration to only a few to a dozen cycles of the line frequency.
Hence residual current devices cutting off power in 200ms (matching the 240V line for the 60479 standard) and them being mandated in all consumer settings.