I moved to Germany as an adult from a completely separate biome, and I’ve got terrible problems with allergies I never had in my home country
Same here. Some of the worst seasonal allergies I've ever had was while living in Germany. I'm not sure what exactly was responsible; my guess at the time was some sort of grass but I don't know for sure.
Yes. I relate myself with that. If i am in Italy, France, Spain, Portugal, Poland, no issues.. in Germany, i have terrible problems with allergies too.
> from a completely separate biome
You were off planet‽
I wonder to what degree it's about what you are used to. I grew up in Germany and never had allergies. However, after a few years in the Pacific Northwest I developed seasonal allergies that get worse every year.