One possible risk caused by mains voltages?

-- proliferation of electrical and electronic devices in the home, leading to a

surprising and shocking bill at the end of the month;

-- excessive current flowing in an inadequately sized conductor, leading to

overheating and possible fire;

-- grave mortal danger to a human person, caused by placing his body in-circuit

between the mains supply and a grounded point.

Note that none of these risks is "caused by" the mains voltage. Any risk is due

to careless and inattentive handling of the mains supply by people responsible

for its proper use. In this respect, mains voltage is no more risky than a car,

a bottle of sleep aid tablets, a pistol, or a discarded banana peel.