Building biology / Healthy building / Ecological building

I have long wondered what is always meant by "ecological building" or "healthy building" or building biology. Sometimes I read statements like, in a new house, dozens of toxic substances are built in and one should better pay attention to building biology.

I have searched and researched, but I haven't noticed anything that really distinguishes "normal building" from building biologically harmless building. My first suspects, plastics like multilayer composite pipes or insulation, are apparently completely okay.

Some people address the topic of electromagnetic smog. Ok. Then the whole house is wrapped in some kind of electromagnetic smog cage. Of course, you shouldn't run cables across the bedroom or under the bed—clearly.

Now, for the first time, I noticed a point that is really considered worrisome. Apparently, the usual construction foam is anything but healthy. However, the opinion is also expressed that 48 hours after use all toxic substances have escaped and evaporated.

It is then recommended to stuff interior doors, the front door, and the windows at the edge area (wood fiber? mineral wool? stone wool? jute?) instead of foaming them with construction foam. Is there any truth to that? Where else is construction foam still used?

Do you know of any other areas that unquestionably fall under building biology and are not just a feeling?

I would be more concerned about prefabricated houses from the 70s than about new builds (wood preservatives, asbestos). Electrosmog and mobile phone radiation are significantly overrated (and no one wants to do without them anyway). Smoking, fine dust, mold, radon in the basement, etc. are certainly more worrisome.

Of course it is true that there is much more harmful stuff to be found in old houses. But especially in new construction, more and more companies are involved, so that naturally everything is top only with them and one would have to worry about building biology safety etc. with competitors. Therefore, I wonder what it means, for example, to build well according to building biology in 2016/2017 vs. standard construction methods!?

General abandonment of anything that can off-gas, use of building materials with a favorable CO2 balance, shielding of radiation sources (=electronics), avoidance of petroleum-based materials... perhaps also preserving craft traditions, focusing on durability

In the case of a controlled residential ventilation system, there is then no problem at all, right?

... at least if the house is not located on a main road ...

Basic rules of building biology include the natural regulation of moisture. This, in my opinion, already excludes controlled residential ventilation.

More can be found on the website of the Building Biology Association (verband-baubiologie.de/baubiologie/grundregeln-der-baubiologie/).

How this is then implemented concretely (which building materials, which companies) would be interesting ... ;-).