I have fairly impaired lungs, so I am pretty sensative to molds, VOG, pollen, and other airborne pollutants (both natural and man made). I live in Waianae area and we have almost no mold. You will get mold here in tubs, toilets and sinks over time, but it is pretty manageable with keeping those areas clean and as dry as possible (ventelated). Over here, the valleys are all angled in such a way that they seem to catch and channel the vog here, and I have had a lot of issues with VOG, but not molds or pollens (mostly grasses and nonflowering tress as the natural/native plants).
When we lived in Hawaii Kai, the VOG was there at times, but nothing like the west side. Mold issues were about the same as I described for Waianae, and pollen was not bad, but a little worse than the west side.
I have a buddy who lives in Kaneoa (known him at work for more than 15 years), and they don't seem to have much VOG, but he has more mold issues and pollen and flowering plant scents are problematic for asthmatics or those with allergies. Lot of rain there!
West side of the north shore APPEARS to me to be a little wetter than the west side, but the way the island is shaped, I don't think they get much VOG, and the plants are mostly non-flowering (i.e. lower pollen issues), but commutes to employment become a challenge. I know a guy who lives up there and loves it (another work associate), but I couldn't deal with the commute - bad enough if your not so remote! Mold is comparable to what I deal with in Waianae.
Hardly a scientific study I know, but I have lived in the different areas across the south side of the island, and know well guys that live on the east and north sides too.
You could go to Mililani, but then I would say just move to inland northern CA - they are about the same, but CA is CHEAPER!
(maybe the only place some one can make that statement about CA!
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