Calandra and Aaron - the new environmental warriors

There's an important environmental thread in 'Calandra's Spring' which impacts on the plot and the characters.  As I have been travelling around the world, particularly in Mexico, I have noticed that awareness of the issues is growing.  However, there is still a shocking disdain for keeping places free of plastic wastes, composting and air and noise quality control.  Mexico is the noisiest place in the universe!  The Big Bang would have been welcome here as an attention getter for some party or product!!  The noises, sights and smells of the place soon become annoying as they are so relentless.  Among my acquaintances, there is a high deafness rate and I worry about the next generation as car stereos, boom boxes and iPods permanently set to 'high' are the norm.  The smells of cooking, of garbage and still, fermenting water below the roads are inescapable.  What is this going to do to the evolution of the human body?  Thicker hair growth around the ears and nose perhaps?  More bone around the skull to shield the brain from the noise?  Could this be a new quest for our heroes?