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The surprising 2 aspect to me are: first, how the healthcare community mute down the causes of diseases such as hypertension. A former colleague told me how his doctor whispered to him that his stay in that big city is not long enough to have cause hypertension, which can be caused or exacerbated by air pollution. Studies have demonstrated a link between exposure to air pollutants and elevated blood pressure, which is a key risk factor for hypertension. Long-term exposure to particulate matter (PM2.5 and PM10) and nitrogen dioxide (NO2) was associated with increased blood pressure and a higher prevalence of hypertension. For every 1 μg/m³ increase in these pollutants, the odds of hypertension rose significantly, with NO2 showing the strongest association.

Second,the big role of tires in air pollution. Tyres shed particles as they wear down during braking, acceleration, and cornering, contributing approximately 6.1 million metric tons of tire dust annually to the atmosphere and waterways

It is easy to be 'green' and 'net-zero' when all you do is exporting your polluting production elsewhere and importing the goods while leaving the dirt on the manufacturer's books, and trade away your own pollution with nifty 'carbon credit' scams.

Top marks for never curbing your consumption while claiming the superior virtue position.

Extra credits for wagging a damning finger at those 'polluters' that actually make and ship your stuff.

For those who are worried about indoor air pollution like me, I found out thanks to this [dynomight post](https://dynomight.net/ikea-purifier/) that having an efficient air purifier is a low bar and is actually quite accessible to poor people like me !

What still baffles me is the reduction in SO2 emissions due to regulations on shipping fuel.

How did the shipping industry accept / manage / afford to switch fuels (presumably, to more expensive ones) in order to follow the regulation ; as opposed to delay / deny / deflect, or plain old lobbying the hell against the changes ?

Are we in a "Montreal protocol" situation, where the alternative was existing and acceptable and in the same price range ?

Or did one actor implement coercion differently ? Was a standard change made, that enabled drop-in replacement ?

(If we were living under Discworld-like physics where narrativium existed, I would understand _why_ the change happened : it's making climate change worst, so of course there is all the power of narrative irony.

Are we in a world governed by narrative irony ? That would explain so many things...)

What's scary is that all significant sources of pollution are going down, except the ones related to agriculture (ammonia and methane) which are showing no signs of slowing down. I feel like you can bend the heavy industry because it's just "a few" people to convince, but you can't change 7B people's eating habits :/

One of the most striking aspects of air pollution is how invisible yet pervasive its effects are. Unlike more immediate environmental disasters, air pollution slowly chips away at public health, reducing life expectancy and quality of life, often without dramatic headlines. The comparison to starvation as a "frailty multiplier" is an interesting one; pollution doesn’t always kill directly but makes people more susceptible to fatal conditions.

Regarding the reduction in SO₂ emissions from shipping fuel, I’d love to see more discussion on how international regulatory pressure (e.g., IMO 2020) managed to enforce compliance in an industry notorious for cost-cutting. Was it simply a case of the alternatives being feasible enough, or did global coordination and monitoring play a stronger role than usual?

Something I haven't quite figured out is why my perceptions of cities' air pollution differ dramatically from their readings as reported by air quality sites.

I suspect readings are quite dependent on the specific location of the reading device. E.g. if the air quality monitor is located in a claustrophobic city street with lots of motorcycle traffic (e.g. Nha Trang), air pollution might be through the roof, but 100m away on the beach it might be clean(ish) air. Similar for 'leafy' cities (e.g. Singapore), where 100m can make a huge difference in air quality e.g. near a park vs beside a busy road.

Curious to know if the science backs up my suspicion that ostensibly 'polluted' cities sometimes have unpolluted alcoves (and 'clean' cities have spaces with bad air), so your micro environment really matters (more than the 'average' reading for that city, anyway).

Really wish they showed deaths per capita instead of raw deaths for all their data sources. It would be better for doing country by country comparisons

It's wild how many pollutants trace back to the same root cause: burning stuff. Fossil fuels, biomass, agriculture byproducts - it’s all combustion and decomposition in different forms.

Does anyone have advice for how to balance air purification with CO2 levels? My apartment will sit at around 1200 PPM if the windows are closed, but if they are open I would think running a purifier does nothing.

Perhaps the most surprising sources of particular matter is... sea spray. As water crashes around, stuff in the water (e.g. salt) often ends up suspended in the air. This apparently contributes a non-negligible percentage of PM2.5 matter in coastal areas, though exact percentages are hard to come by.

I fondly remember the police driving through my small town, telling everyone to stay at home because the tire yard is burning again.

And all these claims are backed up by some hard scientific proofs?

I wish articles like this would give some attention to how much we've already improved. We used to drive leaded gasoline, for example. The amount of damage that caused puts NOx to shame.

The charts for black carbon seem to have the labels for "Buildings" and "Energy" switched.

Tangentially: Belgium's interregional environment agency (irceline) publishes very detailed information on our (awful) air quality: https://irceline.be/en

It's interesting to see the number of deaths caused by pollution. But everyone will die of something. Could it be that many of those people whose death was caused by pollution may have been frail and close to death anyway? I wonder if it would be more useful to talk about quality-life-years (QUALYs) lost as a result of pollution. Probably much harder to get that data though.

I thought that this article will address an elephant in the room but either it missed it or I missed it.

My problem with pollution is that… you need to measure it, and those who pollute don’t do it consciously. Anecdotally I often drive through a small town. You can smell pollution, a plastic smell. In winter you can see column of smoke coming out of chimney. Sometimes it’s milky white, sometimes it thick black. There are many like that. I asked shop keeper is it happening often, she confirmed and said that no one is interested in doing otherwise, installing sensors was directly opposed by town council.

The town is not on a pollution map. Nearby cities are with medium-high pollution but that particular region is supposedly clean as reported by a single sensor positioned somewhere on a hill.

It’s not like there is one town like that in the world. There are nations that pollute heavily and don’t care and don’t meter the impact. I would be curious if all the effort, regulations etc. are worth it when applied to average Joe versus huge polluters.

In 2019, ambient air pollution claimed the lives of young children at alarming rates in several countries. Here's the top 10 list of countries with the highest number of deaths per 100,000 children under 5 due to ambient air pollution: Nigeria – 18.95 Chad – 18.10 Sierra Leone – 12.02 Mali – 10.56 Guinea – 9.90 Niger – 9.64 Cote d'Ivoire - 9.04 Central African Republic - 8.79 Cameroon - 8.69 Burkina Faso - 8.68

These numbers highlight how air pollution isn't just an urban problem — it's a public health crisis in low-income countries where children are the most vulnerable.

Source: Baselight analysis using data from Our World in Data, originally supplied by the World Health Organization (WHO). https://baselight.app/u/pjsousa/query/top-10-countries-with-...

The deaths breakdown by region is interesting:

Africa: 1.8M

South America: 149k

North America: 179k

Australia: 4k

Europe: 434k

Asia: 6.3M

I guess to keep it positive, I'd say "Great job, Australia"!

Does anyone recognize the plotting library they're using? Those interactive charts are really nice.

Interesting article. I always assumed that a large part of the "soot" air pollution in cities came from car tyres as well, since their compounds are one of the main sources for the dust that deposits in apartments.

After experiencing the COVID-19 pandemic, I have developed the habit of wearing a mask.

So is domestic aviation negligible in every way? Is non-domestic aviation part of the transport category? Not clear to me.

Looking at how much pollution is from energy, solar does seem to be the best thing that can happen in current timeline to humanity. Global warming AND pollution gone in a single stroke.