Outdoor symptoms: daily patterns in ozone

[runcyclexcski]

I have posted here about 2 weeks back asking what others thought about the reason behind their variation of asthma symptoms throughout the day (morning vs evening), especially outdoors. Sorry for the long post, just had to get this off my chest.

It's been hot and sunny here in Basel, CH, for the last 2 weeks. Even though the tree and grass pollen is mostly gone, I still feel chest-tight outside or when opening the window; and it's worse in the afternoon. Staying indoors helps; wearing an FFP mask outside (which is supposed to take care of PM2p5) does not. I always attributed the asthma on hot days to humidity, pressure, temperature, or the inefficiency of the mask to filter particulates. Then my Swiss GP told me about ozone and NO2. I knew about these triggers, but I thought that only notoriously polluted cities like London or LA should be worried.

So I checked hourly ozone data from a nearby station in Basel (located two blocks away), and it is consistently low at night (reaching a minimum at 7 am at ~20-40 ppb) and is consistently high during the day (reaching a peak at 3-4 pm at 120+ ppb, when I am starting to get tired of my chest symptoms and usually need my rescue inhaler). They have data going back to 2000, hour by hour, and the ozone periodic pattern repeats day after day; it's also worse in the summer (more sunny days) than in the winter. 60-75 ppb ozone has been shown to cause inflammation and to affect lung function: there is a rather long document about this by the US EPA (with references):

govinfo.gov/content/pkg/FR-....

I am not saying that my daily variation of asthma symptoms is all due to ozone, but I think O3 definitely contributes, and there must be synergy between pollen, O3/NO2. All my major asthma attacks in the last 3 years took place on hot sunny days, even while I was wearing an FFP2 mask (which filters the particulates, but not the O3). Having two major factors -- pollen and ozone -- at their lowest in the morning is a strong case for venturing outdoors early in the morning -- e.g. for exercising, which I really need to stay sane. Wearing a respirator with activated charcoal cartridges helps (I can even ride my bike in it), and this is consistent with the literature that claims that charcoal removes some of the ozone:

escholarship.org/uc/item/87...

In sum, it appears that every season has something to offer for the asthmatics. In the winter, it's the smoke from the burning wood and charcoal and dry/cold air (but no ozone and/or pollen). In the spring, it's the pollen, the grass-burning, and the odor of fertilizer. In the summer, it's the ozone, the pollen, and the air pollution. In the autumn... I feel mostly OK in the autumn, actually, but others mention mould from the decomposing leaves. My defenses are Xolair, steroid inhalers, the rescue inhaler, rescue steroids, an FFP2 mask (if particulates are the problem), a full respirator (when ozone or smells are a problem), staying indoors, exercising indoors, and my "safe space" in the filtered-air tent (HEPA+activated charcoal).

[Bemoresquirrel]

I’m glad that you have found a good GP. I’m not sure why ozone & asthma isn’t mentioned more often, as it is well documented.

I found out that ozone was irritating my lungs by accident, in the mid 90’s, when we were using an ioniser. We use air purifiers with carbon filters, which seems to be the only way to reduce ozone in the house (we live in a rural, predominantly arable area).

I read recently that one of the side effects of reduced vehicle emissions is ironically, an increase in ozone due to less nitric oxide in the atmosphere to suppress the ozone. This was noticeable in London during lockdown, although the hot weather also didn’t help.

You may find this interesting, it’s a much better read, than it sounds!

gov.uk/government/statistic...

[runcyclexcski in reply to Bemoresquirrel]

Thank you Rosey! I found that I can learn smth from every doctor -- no single one would know everything. This was the first time I was reminded of ozone as a trigger by a doctor...

I read the gov.uk paper, and I found it interesting that the rural ozone was somewhat higher -- I did not expect that at all. In Switzerland, ozone is lower up in the mountains which I attributed to having less traffic. I wonder if DEFRA publishes O3 data, but I have stopped trusting DEFRA data after they consistently reported air quality in Leicester as "excellent" in the winter, while my own and a colleague's measurements were showing 3x higher in PM2.5 than DEFRA's.

I would never use an ionizer -- there is an EPA article explicitly recommending against ozone-generators. I know this from my lab work: we use UV lamps to sanitize tissue culture hoods, and I would get sick every time I would get a sniff of that air. I remember the smell very well.

epa.gov/indoor-air-quality-...

"Ozone Generators that are Sold as Air Cleaners"

"Some vendors suggest that these devices have been approved by the federal government for use in occupied spaces. To the contrary, NO agency of the federal government has approved these devices for use in occupied spaces. Because of these claims, and because ozone can cause health problems at high concentrations, several federal government agencies have worked in consultation with the U.S. Environmental Protection Agency to produce this public information document."

[Bemoresquirrel in reply to runcyclexcski]

I loved the mountain air when I visited Switzerland, if only they could export it!

Thanks for the link, my short lived experience with an ioniser was in the mid 1990’s & we soon realised it was a bad idea, both respiratory wise & the mess they make! Personally, I don’t think they should still be selling them for domestic use.

[Gwalltarian]

Despite everything you do to avoid triggers and everything you take to reduce your reaction to asthmatic stimuli you do seem to be very sensitive and still very reactive asthmatically. I wonder if there’s some medication like antihistamines, mast cell inhibitors, leukotrine inhibitors or something like spiriva that might help. Have you thought of trying hypnotherapy to reduce your anxiety - I’m going to see if that can help me.

[runcyclexcski in reply to Gwalltarian]

>>>I wonder if there’s some medication like antihistamines, mast cell inhibitors, leukotrine inhibitors or something like spiriva that might help.

I am on Trimbow, it has the Spireva component. Antihistamines, montelukast etc have no effect.

[Gwalltarian]

Ironic that reduction in NOx causes an increase in ozone particularly in sunny weather! Some of the research linked to above, did suggest that a lower NOx level is followed by a higher ozone level - also associated with VOCs - but eventually achieving lower ozone too. Perhaps the thinner air in the mountains together with less NOx pollution means there’s less oxygen available for ozone production. TB patients used to be sent to the Swiss mountains to provide an environment for recovery.

[DollyDutchGirl]

Earlier this year, I was fortunate to take a weeks cruise to the Norwegian Fjords. The air was truly beautiful - and so clear. As I had literally just recovered from an horrendous asthma attack - that had taken over 5 weeks to begin to feel a little better, I truly appreciated the wonderful clear air.. My GP had been unsure whether or not I’d be able to travel - but thanks to him providing high dosages of antibiotics plus oral steroids - and an emergency pack of each to take with me, I was able to travel and, with my husband taking great care of me, had a wonderful time….😊

[runcyclexcski in reply to DollyDutchGirl]

Congrats on the great trip to Norway! Did you notice the difference when you got back? I have been to NO several times (including an Easter trip to Geilo for xc skiing), and I agree about the air. I would not dare taking such a long trip at the moment, I need to build up the courage. It usually takes a several months without chest tightness to start any long-term planning.

[DollyDutchGirl]

Thank you for your kind response to my post, it is appreciated - and yes, I definitely did notice a difference when I returned home. In hot weather, especially when the pollen is very high - I simply have to stay indoors with the windows shut…🤦‍♀️🤦‍♀️. The beautiful spring air of the fjords was truly wonderful. Unfortunately, I couldn’t live there because the bitterly cold winter air would just about finish me off…😂🤣 I’ve also found that early spring - and early autumn are now the best times for me to travel….and to avoid summer in very hot countries - and to avoid winter in very cold places. I was only diagnosed with asthma 4 years ago at the tender age of 73 - and have been very fortunate, in having lived an exciting life, travelling and enjoying extended holidays in amazing places around the world - so now, I don’t really mind being restricted to travel at times when the climate isn’t too extreme….😊

[mikeh36ma]

Thanks for your detailed analysis. do you think that air-bourn fungi could also be a contributer.

[runcyclexcski]

Mikeh -- fungi spores are above 5 micron in size, these should be taken care of by respirators.