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Japan is gripped by mass allergies. A 1950s project is to blame

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Re: Japan is gripped by mass allergies. A 1950s project is to blame

#81

Post by niemandhier »

vikramkr wrote: post #58
niemandhier wrote: post #54

“Arboreal sexism” is a similar phenomenon: We prefer male trees in cities since they do not produce fruit that drop on the streets. The result is a much higher pollen load.

That's not actually a thing. Very few trees we plant have specific male vs female plants. One of the few that does that gets brought up in this context, ginko, tends to have male trees preferred because the fruit kind of reeks. Ginkgo fruit is also toxic so you really don't want masses of it getting washed into local waterways in ecosystems the tree isn't native to - not a great time for the local wildlife. A signifi…

Cool, I did not know that this is so disputed a quasi factoid. Thanks for cleaning my brain!

Germany has “Baumkataster” which are databases for public trees in cities, they save all kind of tree metadata but gender is missing …

https://hub.arcgis.com/search?tags=baumkataster

Re: Japan is gripped by mass allergies. A 1950s project is to blame

#82

Post by Tangurena2 »

DANmode wrote: post #33
dv_dt wrote: post #24

Hmm, I'm also wondering about studies about overly sanitized environments for children being correlated with higher allergy rates. I guess poking around for a good representative study, it's actually low diversity of microbial exposure, not "cleaning" per-se that is correlated - e.g this is one reason why households with dogs have lower allergy rates. A monoculture of certain tree species also implies less microbial…

It can go the other direction, too: exposure to moldy home environments gave me (now resolved) food sensitivities, dust allergies, pet-associated allergies, etc. You can definitely undertrain, or overwhelm, the immune system if not cautious!

Don't underestimate the amount of cockroach debris present in a modern home. There's a positive correlation between asthma and in-home roach population.

Re: Japan is gripped by mass allergies. A 1950s project is to blame

#83

Post by mattmcknight »

reeredfdfdf wrote: post #35
INTPenis wrote: post #34

Earlier quoted context omitted.

Pollen allergies have definitely skyrocketed in Sweden. We used to be able to sit in an office and work all year without hearing people sniffle and sneeze. Now it's like an epidemic, at least half the office is affected.

Probably we can blame higher hygiene standards, or some other environmental factor for it. Forests haven't changed much in past decades. Here in Finland I've never been affected by any kind of tree pollen at all, but somehow timothy grass pollen gives me horrible symptoms, forcing me to take antihistamine most of the summer. I lived my childhood near farmland and forests, so definitely got exposed to both forms of po…

Perhaps we can blame exposure to actual pathogens which resemble the pollen in some way, triggering a misdirected immune system response.

Re: Japan is gripped by mass allergies. A 1950s project is to blame

#84

Post by dathinab »

flohofwoe wrote: post #14

Hmm, most German forests are also vast monoculture 'tree farms' and have been for the last 250 years (also caused by large scale deforestation in the centuries before). In the Ore Mountains we also have those yellow clouds of pollen coming off spruce trees every few years, covering everything with a thin yellow dust layer, yet I'm not aware that the number of people with pollen allergies is exceptionally high (oth, m…

one one had Japan seem to have quite bad luck with the specific tree(s) mass planted

but also on the other hand in Germany problems with allergies are very common and a pretty big deal for many people, it's just that we got used to it

but also while Germany has not-very-diverse "tree farms" for a very long time, the level of monoculture got way worse in the last 70-100 years AFIK, especially after WW2 the only way to cope with the extreme high demand was to mostly plant very fast growing trees. I.e. mostly spruce and pine.

Idk. if allergies got worse due to this and we just didn't notice because of having so much bigger problems (like many cities lying in ashes) or if Germany always had similar bad allergy problems. But this WW2 induced increase in monoculture is still a huge problem even ignoring allergies as this made German forests especially susceptible to things like pests and adding stress from climate change has lead to mass dying of trees in some regions.

Re: Japan is gripped by mass allergies. A 1950s project is to blame

#85

Post by the_af »

INTPenis wrote: post #59
reeredfdfdf wrote: post #35

Earlier quoted context omitted.

Probably we can blame higher hygiene standards, or some other environmental factor for it. Forests haven't changed much in past decades. Here in Finland I've never been affected by any kind of tree pollen at all, but somehow timothy grass pollen gives me horrible symptoms, forcing me to take antihistamine most of the summer. I lived my childhood near farmland and forests, so definitely got exposed to both forms of po…

Yes timotej is my allergy as well. And I got it as an adult, in 2009. So 26 years without any allergies, then suddenly, one summer in Helsingborg, the air was thick with pollen. I remember the smell was like cheese doodles in the air, musty. Once I got back from an errand in the city my face was leaking, I walked to the pharmacy with blurry vision to get my first antihistamines. Ever since then every year june is a n…

Once you get sensitized, it gets worse every year, right?

Since my teenage years I was mildly allergic to pollen, and now in my adulthood it seems to be getting progressively worse. Each spring is worse than the previous one, and the antihistamines do less effect (or so I subjectively feel).

Re: Japan is gripped by mass allergies. A 1950s project is to blame

#86

Post by croes »

reeredfdfdf wrote: post #35
INTPenis wrote: post #34

Earlier quoted context omitted.

Pollen allergies have definitely skyrocketed in Sweden. We used to be able to sit in an office and work all year without hearing people sniffle and sneeze. Now it's like an epidemic, at least half the office is affected.

Probably we can blame higher hygiene standards, or some other environmental factor for it. Forests haven't changed much in past decades. Here in Finland I've never been affected by any kind of tree pollen at all, but somehow timothy grass pollen gives me horrible symptoms, forcing me to take antihistamine most of the summer. I lived my childhood near farmland and forests, so definitely got exposed to both forms of po…

Trees react to climate change.

After droughts some release more pollen as a survival reaction

Re: Japan is gripped by mass allergies. A 1950s project is to blame

#87

Post by Tangurena2 »

OutOfHere wrote: post #44

Doesn't pollen also have to do with the "gender" of the trees? In gendered trees, male trees emit pollen and female trees intercept pollen. Not all species of trees are gendered (dioecious) but various are. If reforestation uses male trees at the expense of female, then pollen count will be higher. Urban developers who make the mistake of using male trees, because they don't drop fruit/berries/seed pods, will make th…

Most trees (about 75%) contain both male & female flowers. Of the rest, about half are species with separate male/female trees and about half have separate male/female flowers (on the same tree).

Re: Japan is gripped by mass allergies. A 1950s project is to blame

#88

Post by anotherevan »

Allergies are weird. I definitely became more sensitive to hay fever after a gastric bypass.

I have a friend who for no apparent reason developed strong allergies in their sixties. Particularly to goats milk.

So much so that they will not go to a restaurant that has goat milk products (e.g.: halloumi cheese) in their kitchen due to one too many visits to the hospital emergency ward.

Re: Japan is gripped by mass allergies. A 1950s project is to blame

#89

Post by moritzwarhier »

dv_dt wrote: post #24

Hmm, I'm also wondering about studies about overly sanitized environments for children being correlated with higher allergy rates. I guess poking around for a good representative study, it's actually low diversity of microbial exposure, not "cleaning" per-se that is correlated - e.g this is one reason why households with dogs have lower allergy rates. A monoculture of certain tree species also implies less microbial…

I wonder why we focus so much on this claim, when there are many studies giving other plausible explanations.

> Living less than 75 m from the main road was significantly associated with lifetime allergic rhinitis (AR), past-year AR symptoms, diagnosed AR, and treated AR. The distance to the main road (P for trend=0.001), the length of the main road (P for trend=0.041), and the proportion of the main road area (P for trend=0.006) had an exposure-response relationship with allergic sensitization. A strong inverse association was observed between residential proximity to the main load and lung function, especially FEV1, FEV1/FVC, and FEF25-75.

Effect of Traffic-Related Air Pollution on Allergic Disease: Results of the Children's Health and Environmental Research - PMC - https://pmc.ncbi.nlm.nih.gov/articles/PMC4446634/

> The most serious issue might be the growing trend in sensitization to pollen, especially in urban settings (7, 8); in fact, people living near heavy traffic are affected with pollen-induced respiratory allergies more than those in rural districts (9). The sudden rise in environmental pollutant levels due to industrial development and urban motor vehicle traffic has affected air quality and consequently, the severity and mortality from allergic diseases (10). Some evidence suggests that air pollution might cause new cases of asthma as well (9, 11).

Interaction Between Air Pollutants and Pollen Grains: The Role on the Rising Trend in Allergy - https://pmc.ncbi.nlm.nih.gov/articles/PMC5941124/

This doesn't mean that exposure to biodiversity doesn't play a role, but when it comes to explaining the differences between rural and urban settings, this explanation seems more plausible to me than the hand-wavey claims about people supposedly cleaning their apartments more in cities.

Personally, I have seasonal asthma associated with pollen, since childhood, and I'm from a big city.

I have a much harder time walking next to a busy road in allergy season than being somewhere more rural, even when there are birch trees right in the vicinity of where I am, one of my allergenes.

It's not b/w of course though, the pollen can trigger it not only in the city. But then it's usually very mild.

My asthma is seasonal, allergy-associated, and still, the worst stressor I experience is pollution and car exhaust. Well, the worst unavoidable stressor.

Alcohol also seems to do bad things to my allergy response.

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