Yes, time spent indoors, and the West's obsession with anti-septic environments. I bought a little cabin on a lake in NJ after moving from NY. I didn't bother s

Yes, time spent indoors, and the West's obsession with anti-septic environments. I bought a little cabin on a lake in NJ after moving from NY. I didn't bother sealing every crack and nook with sealant given my energy bill was reasonable, and I liked the fresh air exchange over time. Friends moved up there and built air-tight houses with all the modern materials with foams, glues, carpet backing, tiling and other products that need a significant time to off gas, trap particulate and moisture, and as we now know, mold can thrive on almost anything with moisture. Anecdotal, but it seemed they were at the doctor's office 2 to 3x per year vs. my kids only going for checkups. People are now hypersensitive to so many things, and I believe a lot is due to this approach to what it means have a healthy home and household. I have raised 4 children, and aside from some mildly annoying hayfever for a very short period for 2 of them, they are mostly non-allergic and I am grateful, have no medicinal allergies. I also think we have grown a bit hypochondriacal and have actually fed into this phenomenon. There are even studies claiming 50% more likelihood to contract MS if you are exposed to the solvents or chemicals in paint thinners and household cleaning solutions. Even "organic" products in large amounts do not bode well for most people's health, so housing construction that claims to be "organic" with low VOC elements used sometimes doesn't even address the need for sufficient air exchange with fresh air over environmental ratings on windows, appliances, etc. Somewhere in the middle there is a happy medium from my natural materials, drafty cabin, and an air-tight, "organic" material house. We had mold in the attic and it was black and after reading about it back in the late 90s early 2000s I went up and cleaned the rafters with Clorox (yes, chlorine, I know. My nuclear solution!). and opened the once-closed off ceiling to the attic. I put in skylights and opened up the A-frame for more air and light. Nobody in my family at the time, including my newborns seems to have suffered from having lived with this black mold, but evidently, there are many and I am not sure how prevalent dangerous black mold is from your generic black mold, but as I have said earlier, anything in too large a quantity can be deleterious to your health. Too much grain dust in the air would irritate you too and in high enough concentrations probably kill you over time!