A lot of environmental headaches are allergies or pollution, and a good chunk of those are things in your own house - for example dust mites or fumes from plastics/paint/carpet.
Theres a (pretty sure it's) Billy Connolly (comedian) story about buying a house and the previous owners kept getting sick: something to do with the floor varnish.
Sorry, cant look it up right now- im driving and the heavy rain on the autobahn is making me late. My own fault for drinking until 5 this morning, i guess.
A lot of environmental headaches are allergies or pollution, and a good chunk of those are things in your own house - for example dust mites or fumes from plastics/paint/carpet.