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by irrational 332 days ago
The second leading cause of lung cancer is radon. My high schooler came home and said her science teacher said everyone should do a radon test. I scoffed, but humored her by getting a kit from Home Depot and sending it away to a lab. The results came back very high. So I purchased an electronic radon monitor and it showed almost the exact same results. Well, crap. I installed a radon mitigation system and now the numbers are almost nil.
9 comments

The difficult thing for me is that while I believe radon can cause lung cancer, I think products are often sold based on fear. “Second leading cause” doesn’t really mean anything in isolation, does it?

What slice of my mortality pie was radon before and after spending $5000? Could I spend $5000 to cut a bigger slice out of it in another way, like eating better or hiring a grizzly bear to make me exercise more often?

I think action is better than decision paralysis, but I wish I could make much more informed decisions.

For 93% of people the only cost is the $15 test kit to verify "yep, don't need to even think about it".

For the other 7% that then need to really do a cost-benefit the data is out there but you do need to go through your specific circumstances to get a meaningful number. The risk levels vary vastly (orders of magnitudes) between both the radon level and your life choices/situation, so it's relatively meaningless to share individual cost-benefit analyses.

> so it's relatively meaningless to share individual cost-benefit analyses.

yes

1. it's very affordable to fix

2. long term exposure always adds a non negligible risk

so just fix it

I'm confused why people get hung up on a cost-benefit analysis which is pretty much always guaranteed to be a net positive. Either slightly or majorly.

And if it's a rented apartment in many countries you can force your land lord to fix it with a wide arsenal of funny things you can do if they try to refuse :shrug:

What you quoted doesn't really agree with what you're stating, which is really "it's meaningful to share the cost-benefit analyses because they'll all say it's worth it".

The reason they will not all say it's worth it is because there is nothing "magical" that happens at 4.0 pCi/L. Whether that is the sensible threshold vs doing something else with your money is a very different answer for a non smoker who makes 35k/y vs a smoker who makes 250k/y.

Saw someone built his own DIY radon fan system. Think it was a clip from Swedish public service tv. He built it using 12V fans from server racks. Guess that is an option as well.
Why? Purpose built radon fans are not expensive and at most you have some pvc and fans.
Yeah, this is the correct heuristic.

Spend $15 or $100 for one or two measurements, *then* worry about cost to mitigate.

Advice also applies to mold. A lot of people worry about mold in their house. It's actually quite straightforward to determine if this is actually a problem: Home Depot sells "test kits" for a few bucks that are essentially petri dishes. Buy two of these, put one inside where you are worried and then the other outside and wait 3-4 days. If they look radically different, then send the inside one in for actual analysis, which is an additional ~$40 USD. Then and only then do you need to action and by that point you know exactly what the problem is so you don't have to pay some "expert" to sell you some massively expensive mitigation strategy that you probably don't need.
Is it common to have an invisible mould problem? Lots of people are in the situation where there is really visible mould but the problem is getting their landlord to fix it, without getting into allegations over drying clothes inside etc.
There's a lot of fear over things like black mold in the states. It's extremely rare but it can be life threatening, and it's one of those things that people see and get nervous about when they see that for instance their HVAC vent has mold spots, that they are breathing toxic air. 9 times out of 10, it's totally fine. This method mentioned above gives homeowners the peace of mind that they aren't poisoning their families accidentally for an extremely affordable price. The alternative of calling mold remediation experts in is going to be extremely pricey, and those people cannot be trusted to be upfront on whether your mold problem is 1. actually a problem and 2. actually dangerous - because they make money on selling expensive remediation solutions.
I would expect that mold can build up ie in ventilation where it remains unseen unless it literally clogs he whole system. You can't see the spores an often there is no strong foul smell.
honesty depending where you are such allegations might be very baseless & meaningless for many reasons like

- high base humidity of the place (e.g. the city where I live has a yearly avg. humidity of 70%, but specific to my apartment and ignoring the dry seasons over 80% is the norm (also for context not tropical but central EU, it's stuff like 20C+85% humidity). So airing out your room might increase air humidity...

- in small apartments it's the quite often norm that the side effect of taking a show can temporary rise humidity quite a bit, even if you ventilate properly. Most bathrooms in small appartments are just not well designed wrt. this (context I'm not speaking about long hot showers, but short normal warm showers).

- in small bed rooms night sweat can rise humidity by quite a lot, mostly if you are slightly sick but anyway

- just basic flowers can raise humidity, too

excluding dry areas IMHO for most no large apartments the landlord has forsaken any right to claim it's your fault if they don't provide reasonable measurements against humidity (even if it's just a half way decent (noise wise) air humidifier. Reason: Just standard normal expected usage will cause to high humidity level even if you do air out the apartment twice a day (which depending on weather conditions you might not even be able to do)

Sadly that isn't necessary the local laws/regulations POV.

Our local library system offers these to borrow for six-week spans (or whatever the length of the testing is). It’s a one-and-done deal and you’re good for as long as you stay in your home. Batteries included.
The EPA recommends home owners mitigate with radon levels of 4 pCi/L and above, and the EPA recommends home owners mitigate ”consider” mitigation at levels 2-4. Often you will see people post radon results in the 10+ or even 50+ range, which may lead you to think 4 pCi/L is not too bad, but in fact exposure to that level is the equivalent of 8 cigarettes a day or 200 chest X-rays/year.
Given the average level of radon in the air outdoors is 10% of that, being outdoors is 20 chest x-rays per year, eh? That’s almost a cigarette per day being outdoors!

https://www.epa.gov/radon/what-epas-action-level-radon-and-w...

The EPA doesn’t make such creative claims. But the sites that do will also conveniently sell you stuff.

https://radonbegone.com/what-does-your-radon-number-mean/

https://www.nationalradondefense.com/radon-information/radon...

One cigarette a day doesn't sound that bad for you. 40-a-day smokers exist and while they're unhealthy, they're not universally dying in their fifties, so one fortieth of that effect seems small.

The biggest risk of smoking one cigarette a day is not that it will give you cancer, it's that it will give you nicotine addiction which will lead to smoking twenty a day and getting cancer. Radon exposure doesn't have that effect.

Cancer isn’t the only risk though, the 100 other things are pretty bad too. It isn’t ‘just’ that you might die of cancer, it’s the decades of leg ulcers, stroke, heart and lung disease etc.
Those are some powerful claims, do you have any links for that? Generally 2-pack smokers that started early ie in their 20s or even earlier don't live till retirement where I live, but I agree its a small sample and generally such people don't live a healthy life overall.
It’s very region specific. Just like some regions don’t have many basements, some have a lot of radon:

  Here in Maine about 36.5% of radon test results equal or exceed the Environmental Protection Agency (EPA) action level of 4 pCi/L, according to the Lung Association’s “State of Lung Cancer” report.
https://www.lung.org/media/press-releases/maine-radon-2024

If you own a basement in Maine, you should probably test it!

The indoor level of radon isn't going to be lower than outdoors. Indoors is either the same or higher than outdoors. Your level of exposure to radon will not go up by going outside. That's your background exposure level, and is already baked into the calculation of how much an effect an elevated exposure to radon in your home will have on you. Radon is a serious thing to consider, especially if your home has a basement. Radon mitigation is not a scam conspiracy.
Like any good scam, they take a legitimate issue for few and sell it to many who don’t need it.

These websites will try to tell you that the average indoor radon level is equivalent to 2.5 cigarettes per day or 66 chest X-rays per year. The EPA doesn’t make that claim though.

The EPA already publishes the direct risk levels for a given pCi/L reading. Adding an intermediate step of how many cigarettes per day that is akin to is not giving you any new information (but is likely distracting you from just thinking about the risk level itself).
Has anyone ever done a meaningful cost benefit analysis for less than $15?
This is bang on why you're best off to just always start by paying the $15 to do the test and then let that drive whether there will actually be a need to cost-benefit analysis around mitigation costs.
Radon gas is a pretty big thing in construction where I live since our underground is mainly boulder clay (which apparently has or leaks or whatever a lot of radon gas). Anyway, In Denmark a little over 5000 get lung cancer every year, and 300 of thouse are from radon gas. Acording to our Kræftens Bekæmpelse (anti-cancer NGO) there may be an additional 25% risk of radon causing lung cancer if you smoke.

Since around 2000, it's been part of building regulations that you gotta build air-gapped foundations in family homes. Those who can measure radon gas are adviced to buy things to fight it, and you can reduce it to basically 0% for little money.

I never really considered it from an advertisement perspective as it's adviced by our government and non-profit NGO's. So there is that, if that helps you.

> and you can reduce it to basically 0% for little money.

which is why I'm confused by people second questioning how bad it actually is in context of _fixing_ it (not in context of a national health scope)

if there is something which is known to be quite unhealthy in a non small degree, and there is a cheap fix why wouldn't you just fix it. In the end if it's very bad, or slightly less bad or the 10th leading cause instead or whatever doesn't matter, fixing it is affordable and it's guaranteed dangerous on long term exposure so you do it.

I found most people dont know about this or think about this until there is a home purchase and home inspection -- that is when it is revealed, and typically when it is remediated as part of the purchase contingencies. If youre living in the same home for a while, you wouldnt typically know. Also, if you are a renter, you probably wont know and the landlord will probably purposefully not want to test.

In my state, the state forces some of these tests (e.g., smoke detector) as part of the sales process so at least there is some hook for testing.

Is radon mitigation affordable, though? Someone in another subthread said they got quotes between $1600 and $3000. Even the low end of that is a difficult amount to spend for a lot of people in the US. If they're going to spend it (if they even can), they're going to want to know it's going to meaningfully decrease their risk of cancer.

I'm not saying it's not worth it -- that's the point, I don't know -- but I agree with people upthread that it would be nice to have better information with which to make decisions.

I don't know where you live but where I live in the Midwestern suburbs, $3k is on the low end for almost any significant home improvement/repair project except maybe repainting a room.
Midwest here. Radon mitigation usually starts at $1k. And can go up depending if they are drilling into the slab. For most cases it’s a trivial solve.
And those repairs often get put off years or until a house sale becomes dependent on the.
It might be significantly cheaper if installed in new buildings. Even if not, it barely moves the needle compared to the total cost of building a house, and it's almost nothing spread across the lifetime of a typical building.
Relatively cheap for people that own a house
I'm with you on wanting to quantify.

https://www.epa.gov/radon/health-risk-radon

Scroll down to "Radon Risk If You Have Never Smoked". Looks pretty worthwhile to take it from "very high" to "almost nil". If "very high" was in the range of the 2nd highest level listed here, that's 2% chance. That's for lifetime exposure but there's also multiple people living in the house.

If you DO smoke, the numbers look VERY good for spending some cash to get rid of radon. (Of course you should also stop smoking.)

That’s exactly the kind of information I was seeking! If your results come back at some ridiculous level, it could make complete sense.

But if your results come back much closer to normal background levels, there’s not much you can do. Even the EPA says it’s difficult to get it below 2.

Meanwhile, lots of websites out there try to scare you into buying remediation for low values (see comment below).

It’s the perfect bogeyman. Radon. Cancer. Invisible silent killer. And I think it’s demonstrated by the vibe-based “seems like a good idea” conclusions in these comments.

I think that if you start from the belief that radon mitigation is sold based on fear, and doesn't have value, then it's easy to cling to that belief and try to dismiss or explain away or minimize information that contradicts it, and to dismiss people who see value in it as 'fear buyers' who believe in a 'bogeyman' and say 'good idea' to things which, in your opinion, might not be good ideas.

A perspective perhaps different from yours: Avoidable cancer risk isn't great, and smart people* properly weighing the facts have repeatedly judged the value of radon mitigation to exceed the costs.

* - Probabilistically speaking, this includes many who are smarter than you and me

I never heard of the radon cancer impact before and it took me 10 minutes to find couple of representative studies done for my local region which in fact did find the positive correlation between the areas with elevated radon measurements and people living in those areas getting the lung cancer. So, not that "it could make complete sense" but it certainly makes sense. I suggest you do the same research before calling out something as important as this a scam.
$5000? I got a bunch of quotes and none came anywhere near that high and I live in a home that made it difficult to install the system (finished basement, large footprint, three stories tall, concrete outer walls (ICF), etc. I think the highest was $3,000 and the lowest $1,600. I ended up installing it myself for about $500 in materials.
That's only the initial capex though. $5,000 is a realistic swag for install + lifetime electricity + minor system maintenance.
These fans are not using $3000 in electricity over their lifetime.
I guess that depends how old you are when you install it and how long you plan to live but ~$7 per month is not at all an unrealistic electricity usage estimate for the system. 7*12*35 = $2,940.

Edit: E.g. the numbers from this site suggest, for 15 out of the 16 listed fan models, the lifetime electricity cost is likely to be significantly larger than the install cost unless you are already much older at the time you start using the system or you have extremely cheap electricity (or both) https://www.radonaway.com/radon-fan-operating-cost-calculato...

This point always amuses me. Thats like, 1 starbucks coffee a month, or 1 trip to a fast food place a month, or one extra thing at the grocery store a month, or half a movie ticket a month, or half a streaming service a month, or less than half an LLM subscription a month, I could go on for a while.

For the cost, preventing cancer seems like it's a wise investment. I say this as a cancer survivor.

The present value of $7 in 35 years is $1.45, assuming a risk free rate of 4.5%. Paying $2940 over 35 years is much more affordable than paying $2940 up front. If the goal is to be rational about risk, let's right-size the numbers. Otherwise our figures will be misleading.
That is still insanely high. The highest Ive seen for install is $650 but required quite a bit of piping to the exterior.
Just the materials cost was $500. How are they doing labor for $150?
And heating/cooling the fresh air replacing evacuated air + radon.
The air is under your slab. How would it be replaced by fresh air inside the house?
It’ll vary considerably. But I just picked a random round number that doesn’t affect the point I’m sharing.
Radon fan drawing from two basement surfaces (concrete slab crawlspace addition and original stone foundation with cement floor): $1,200.00 usd in 2020 with warrantied fan and included confirmation test kit. US mid Atlantic. The prior homeowner thought radon was a scam too. It doesn’t make sense as a scam for a one-time capital and labor purchase.
> What slice of my mortality pie was radon before and after spending $5000?

You'll never know. The same way people in the exclusion zone will never know if their thyroid cancer was always destined to be or if it really was related to the Chernobyl meltdown.

But spending (closer to $1000) to mitigate some risk from a known threat vector does seem thrifty.

> But spending (closer to $1000) to mitigate some risk from a known threat vector does seem thrifty.

No, there are a lot of known threat vectors.

I might not be in as tight with the grizzlies, but $5k a year for a personal bear trainer seems a bit low. For a regular brown bear sure, but the grizzlies are expensive
Yeah but no matter what, you gotta pay for the bear necessities.
Here is something I found comparing the risk of radon exposure to other risks. Seems like if you don't smoke the risks are much lower.

https://www.epa.gov/radon/health-risk-radon

> What slice of my mortality pie was radon before and after spending $5000? Could I spend $5000 to cut a bigger slice out of it in another way, like eating better or hiring a grizzly bear to make me exercise more often?

I wish more people thought like this. Every time I go to the GP I want to get a printout of my mortality pie based on everything they know about me.

I was actually thinking of getting one too. Is there a particular Grizzly-as-a-service offering that you recommend? I'm also considering signing up for Ostrich-as-a-service, and am really struggling with this decision.
I reckon grizzly bears have negative health side effects too... It's all a fine balancing act.
what's stopping you from getting answers for these questions?
My approach is to think carefully about exactly what I want to know, word the question that way, then throw it to the AI and pray. I think this is better than ignoring it or spending too much time on it.

Question: Where does radon related mortality rank versus other mortality factors in the United States?

<AI "reasons" a bit>

...

Summary: Radon in perspective

Category / Cause Approx. Deaths per Year (U.S.) Rank / Context

Heart disease ~680,000 #1 overall cause of death

Cancer (all causes) ~613,000 #2 overall cause

Chronic lower respiratory disease ~145,000 #5 overall (includes COPD, etc.)

Lung cancer due to radon ~20,000–21,000

Subset of cancer deaths; about 3–4%

Toxic agents (inc. radon, pollutants) ~55,000 ~2.3% of all deaths (includes radon part)

So AI says it's a bit less than 1% of preventable deaths (or something) annually. Probably puts it in the top 150 causes or so. What you want to do with that hypothesis, or whether you want to spend time sanity checking it, is up to you. Hitting the gym to avoid heart disease is like 35 times more important. A radon home testing kit to eliminate uncertainty about this particular <1% risk is a one time cheap thing though.

What the hell would someone downvote this for lol. Freaking Hacker News
Why bring up the AI at all, if you're also making those claims and vouching for that info?
Folks, check out your local library, ours has radon test devices.
Same (Canada).
I’d argue that the leading cause is actually genetics. I come from a long line of people who smoked like chimneys from their teens until their 90s, with no cancers. My mother has spent her life in harsh sun with no sunscreen, and looks like an old handbag, but has entirely clear skin - but her partner, who wears strong sunblock, hats, and all the rest, has had skin cancer twice. So have two of his kids.

Meanwhile, my father’s second wife’s family have pretty much all had or succumbed to lung cancer. None of them smoke, and unless they all coincidentally chose radon-riddled homes in different corners of the U.S., there’s no correlative environmental cause - which leaves genetics.

Is it genetics or probability distribution? If it is genetics, shouldn't the native american be the most immune to smoking? (genuinely asking if there is such a data)
> Although there are over 50 identifiable hereditary forms of cancer, less than 0.3% of the population are carriers of a cancer-related genetic mutation and these make up less than 3–10% of all cancer cases.[

Took me 5 seconds of research. But keep arguing. Opinions are more important than facts.

And you base your conclusion on top of the sample size of what, N=10?
No, on the fact that there are plenty of known variants which increase the chance of lung cancer quite dramatically - moreso than smoking.

It’s not just lungs - things like FAP make your chance of getting colon cancer in your lifetime near to 100%, regardless of how many ginseng enemas you have or whatever the hell else you do.

Variants like TP53 (Li-Fraumeni) or EGFR mutations have measurable, population-level impacts on cancer risk.

Genetics loads the gun. Being alive then pulls the trigger.

> No, on the fact that there are plenty of known variants which increase the chance of lung cancer quite dramatically - moreso than smoking.

But didn't you just say that it is the genetics and not the radon and/or smoking? Can you give some examples of those "plenty of known variants" for lung cancer?

EGFR, as mentioned - it’s the most common cause of lung cancer in East Asian women.

TP53, as also mentioned - gives you a >90% chance of cancer of any variety in a lifetime. 50% by age 30.

Smoking presents about a 20% lifetime risk - and that’s without adjusting for genetic predispositions like CHRNA3/5 which increase nicotine addictiveness and promote tumorigenisis, or BRCA2, or CHEK2, which diminish DNA repair capabilities.

Quite strong claims. I would be interested to read more about those. Do you have any references you can point out? A quick research on EGFR and TP53 suggested they are more related to colorectal cancer and not the lung cancer.
"The second leading cause of lung cancer is radon"

Perhaps. I smoked for 30 years and I lived on and off in Devon for at least 15 years.

There is a bloody great pluton underneath Dartmoor in Devon and Bodmin in Cornwall and so on. Hence lots of lovely granite and radon and stuff.

This is the SW of England (UK). Radon emanates out of the earth and pools in cellars and the like and is a major health hazard. Ideally you know about the hazard and dissipate it. A simple fan will do the job.

I'm not sure it is the second leading cause of lung cancer. There are plenty of other pollutants to worry about.

I think Radon exposure is a serious matter, but its concentration in the USA either is probably overrated OR indeed you have a local geological problem. In Europe we even have the tradition of Radon Therapy for certain pathologies in Spa. Of course, one should do these therapies under medical consultation.

https://www.alpentherme.com/en/therapy-health/therapy/radon-...

> How radon works: Cellular repair in the body is stimulated, the number of free radicals is reduced.

Yikes! Not only are free radicals increased, because you're being bombarded with ionizing radiation, but any cellular repair stimulated is because of the cellular damage done!*

I have to assume "the number of free radicals is reduced" is intentionally written awkwardly and in a passive voice, to avoid adding "...after the "radon therapy" stops.

* - And it's not gonna be a net positive!

Many physical therapies work on the principle of the stimulus and some net effects happen after that is stopped. Even fasting diets work like this according to specialists like Walter Longo: the best part happens when you stop the fasting and start eating again. You could argue something similar happens when you finish the certain exposure to radon after a trip to Bad Gastein.
> You could argue something similar happens when you finish the certain exposure to radon

I could, but then I'd be arguing something I don't believe, and have no evidence to support!

I don't know that it would be worth it to entertain a hypothesis that, as far as I can tell, nobody here believes and has evidence to support.

The hormesis hypothesis has not been widely proven, but it has not disproved either. It's still a working hypothesis. And yes, patients sometime work with hypothesized therapies, especially if conventional therapies don't work for them or they get many adverse effects from them.
If I told you that hitting yourself in the dick with a hammer was good for you, would you have as much support and deference for The Schwanzhammertherapie Hypothesis as you do for hitting yourself all over with ionizing radiation? After all, I can't find any studies disproving it.

Here is how Schwanzhammertherapie works: 'cellular repair in the body is stimulated, the number of dick hammerings is reduced'.

In the early 20th century America also used to have lots of radiation therapy providers. It's quackery, and harmful quackery at that.

Just because you have a tradition of something doesn't mean it's effective. Or safe. Or wise.

People with rheumatological diseases beg to differ. I understand nowadays it's a little bit odd, given the more sophisticated technological therapies that exist, but getting exposure to radon in certain calculated doses is how it was supposed to work.

I agree that the mechanism of "radiation hormesis" is kind of weak, but it has not been disproved as quackery either. https://en.wikipedia.org/wiki/Radiation_hormesis

Absolutely bunk science with no real evidence supporting. It’s like saying autism is created from vaccines.

A lot of the US has radon exposure. I don’t how people come out saying things like you do but at the end of the day it’s exposure to radiation. I have seen it all, people will say it only impacts children or the elderly. Or that it’s an overblown conspiracy. Radon is radioactive, I am sure there are discussions on safe exposure levels but mitigation is so inexpensive and normalized why risk it.

Not on the same level as autism correlated to vaccines. And radiation hormesis has not been disproved as "bunk science" as far as it is widely known.

https://en.wikipedia.org/wiki/Radiation_hormesis

Nothing you have said in this thread has been supported by studies. Everything is a hypothesis or proposal. I would expect if this was real that there would be more concrete evidence over the decades, yet none exist. Maybe it’s not a falsified hypothesis but it’s at best a hypothesis. I am much more into the proven by a study science and medicine and not feelings.
Actually there are many (admittedly weak or low in n) studies in Europe, which show some benefit. I will post some titles later, check this space.

I agree that there are no big prospective studies and probably will never anymore be, because there is really no interest or gain from big pharma. The big time of physical therapies was last century and all studies, at least in Germany, stop by the 90s.

An interesting article to read about the different approaches in Europe and America is this: https://journals.sagepub.com/doi/10.2203/dose-response.06-00...

Please don’t I won’t read them. I already saw the overview ok Wikipedia. Some studies that may suggest hormesis, most of them flawed. Everything is either a proposal or hypothesis. Absolutely it should be studied but those radiation spas are bunk science for now.
Bogoljudow VM (1988) The clinical aspectsof radon therapy. Y Phys Med Baln Med Klim (Sonderheft 1) 17: 59-66

Pratzel et al (1933) Wirksamkeitsnachweis von Radonbädern im Rahmen einer kurortmedizinischen Behandlung des cervicalen Schmerzsyndroms. Phys Rehab Kur Med 3: 76-82

And I found many more particularly from a certain Gunther R who has published a lot in Germany between the 70s and 90s with minor studies referenced. As said before, this is a dying tradition and no one cares to redo the experiments with better conditions, unfortunately. But until proven otherwise, it's all we have.

Thank you for proving my point. These are at best a hypothesis that no global body has approved. Is the LNT model overly strict? Probably. But is there strong evidence that low doses are beneficial? Nope.
I am super uneducated on this, but I thought radon was only a concern for people with brick homes or basements?
It has more to do with the land you’re built on, though basements make it worse.
I have a brick house and a basement, and I have no radon mitigation system, and I live in an area where radon is generally a concern (southeast Michigan.)

Over the last couple years I've had some AirThings sensors collecting data. Last month:

- The one-day average radon concentration detected by the basement sensor crossed over 3 pCi/L once... for a very brief period. Around 80% of the time, the one-day average radon concentration detected by the basement sensor was below 2 pCi/L.

- The one-day average radon concentration detected by the main floor sensor never reached 3 pCi/L and was rarely above 2 pCi/L.

In fact, since January, the main floor sensor has still never reached 3 pCi/L even once, or really gotten all that close. The basement sensor, on the other hand, has reached 4 pCi/L three times this year, with a peak at 5.1 pCi/L for a brief period in May.

I hardly ever check this data, but it is nice to have it. I guess it would probably be wise to double check some other way to make sure that the AirThings sensors are outputting good information, but I have little reason to doubt it.

As long as I'm interpreting the data right, though, it suggests that despite having some of the worst case scenarios for my house, actually it's fine. So I guess it really does depend mostly on the land you're built on. (That, and, you should probably just check instead of guessing.)

My understanding is that a radon reading of 2 is the upper bound for reasonable regular exposure. If you're seeing above that, I'd be inclined to look into mitigation.
I'm not an expert but I've read enough to know this is not a serious concern. If you were to see a reading above 2.6 pCi/L from a one-time test, that would be more concerning, but what I'm actually seeing is occasional jumps above 2.6 pCi/L that last less than a day from continuous monitoring. We're talking events that last on the order of hours for a few days a year... I can open a damn window. The vendor for my sensor recommends taking action if the level is above 4 pCi/L for an entire month, but for me it's barely above 2.6 pCi/L at all. In some months neither sensor ever gets above that.

I think on the contrary if you have a tendency to worry too much things like continuous monitoring systems might not be the best thing for your mental health. I actually was pretty worried since I'm a mild hypochondriac and a friend told me that they got obsessed with CO2 monitoring after getting one. Thankfully for me it has mostly been an occasional curiosity since there's nothing too concerning.

So what is the necessary levels of exposure to have some kind of long term implications? With hand wavy claims to drive fear that certainly will make a pump in radon kits + drive more radon mitigation systems.

I've always been under the impression that there was radon in basements since it settles down there ... maybe the correlation is people who spend long periods of time in the basement with radon exposure (thats a guess fwiw).

Canada has a great website about radon:

https://www.canada.ca/radon

https://takeactiononradon.ca/

My daughter wanted to live in the basement area, so I had it tested for radon even though I guess radon is less common where I live. It came back negative, so I feel okay about it...man, the things you need to remember to think about in life.
What's a radon mitigation system like?