X Files did an episode where the VLF waves from NAVY sonar were to blame literally causing peoples heads to burst. Now while they took it to an extreme, the effect of feeling your head explode is real and someone sensitive to these frequencies will really feel pain...
It was also found that these NAVY VLF sonar waves were harmful to Whales and Pierce Brosnan was behind a campaign to stop the UK and US Navy experiments
http://www.savebiogems.org/whales/
Narrated by Pierce Brosnan
http://www.youtube.com/watch?v=WJEATHUXjlI