The danger of acoustic ELF waves below 10 Hertz in my opinion is neglected,
some say there's no danger, some say there's not enough research but then
you learn that acoustic ELF waves are used as weapons by secret service and homeland securers to keep demonstrators calm or out of reach.
It is said that directed high energy acoustic ELF waves can damage or totally destroy inner organs and may cause instant heart attacks.
In the music business they implement acoustic ELF beats into rhythms to influence the audience.
Remember, way back then, as reported in the Bible:
The Trumpets of Jericho were used to destroy walls.
While the focus is on the dangers of electro-magnetic waves
the acoustic waves might be an equal source of far reaching troubles.
The interaction of high and low pressure weather systems can cause long acoustic waves and affect the mood of humans, for example.
Probably our environment is 'polluted' by acoustic waves we don't see and don't hear but that affect body and soul and maybe even the brain functions.
Just a few thoughts ad hoc.