I actually do think of this. Given that we have little to no cell signal, no big power lines and no above-ground power lines, I figure my exposure is less than most Americans.
But I sometimes ponder that we DO get radio and TV and Starlink and occasional cell signals not to mention home wifi and all that. We are doing a massive population-level experiment. Most of this is very low energy, of course, but some isn't and...
It was found that children living in homes as far as 600 m from power lines had an elevated risk of leukemia. An increased risk of 69% for leukemia was found for children living within 200 m of power lines while an increased risk of 23% was found for children living within 200 to 600 m of the lines.
https://bcmj.org/bccdc/living-near-power-lines-bad-our-healthNow how much power is in a high-tension line? I'm not sure. Normally for a point source, energy (heat, sound, light, EM) decreases as a cube of distance as it expands to fill a sphere. With power lines, I guess it must be a square of distance. So 200m away would be mean a 40,000-fold decrease compared to 1m away, like you might experience if charging your car. The biggest lines run at 3GW. So 3GW at 200m is the equivalent of 76.5kw at 1m.
I'm not an electrical engineer and those are limit cases using what is purported to be the highest energy lines in the world. Still...