
The Weight of Numbers: Air Pollution and PM2.5 - anarbadalov
https://undark.org/breathtaking/
======
anarbadalov
Undark & the Pulitzer Center visited seven countries on five continents to
examine the impacts of particulate pollution on the lives of everyday people,
and to uncover what’s being done — or not — to address it. The project is
comprised of data visualizations, short narratives, on-the-ground 360-degree
videos, an explainer film, and photos from Pulitzer prizewinning photographer
Larry Price.

What's interesting is that PM2.5 is a measurement used by policymakers and
organizations all over the world, yet the average person doesn't really know
what it is, or why it matters. (I know I didn't until we began work on the
project.) And it turns out that while developing nations bear the brunt of it,
this kind of pollution doesn't discriminate, and it's a problem everywhere
from India to Nigeria to California. In fact, a full 90% of people live in
areas that exceed World Health Organization guidelines for exposure, so the
odds are high that wherever you live, you’re breathing it in, too.

[full disclosure: I work for Undark. We're a non-profit science and society
magazine published under the auspices of the Knight Science Journalism
program]

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ggm
Do you work with the people at QUT (Brisbane) or Floreanopolis (Brazil) doing
fine particulate work near airports and in hospitals? my partner did some
proofreading and english-as-a-second-language with these people, fascinating
stuff (as a complete outsider) and very important.

~~~
anarbadalov
We don't. While we do often publish stories on public health issues, we don't
conduct any of the research, we just report on the science. Australia and
Brazil aren't regions we visited for this project, although I wouldn't be
surprised to hear that there are areas experiencing extreme events in both.

~~~
ggm
Australia has a huge depndency on air and road freight with massive diesel
subsidy to truckers and more air miles per Citizen than many other economies.
We also have long hot dry weather. So the fine particulate matter issue here.
Brazil has inadequate health funding and high humidity so gets mould..

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gh02t
I recently built a sensor for particulate matter (using the Plantower PMS7003,
a laser-based sensor) and it's interesting to look at the effects of every day
tasks. Cooking for instance causes a huge spike in PM1.0/2.5/10.0 levels, but
so do more mundane tasks like vacuuming or spraying aerosols.

I'd like to add a sensor for CO2, but it's a bit more complicated. A lot of
the easy to use sensors marketed for the purpose are MOX sensors and the
"equivalent CO2" reading they give is pretty much a complete lie except in a
very narrow range of circumstances.

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legulere
I have a sensor built into an air purifier and have observed the same.
Anything textile-related is bad like shaking out your blanket, which makes
carpets seem horrible to me. But frying stuff really is the worst. You can go
in the hundreds of micrograms, even with induction.

A positive thing I have also learned is that opening the windows works best to
get PM levels to a background level. Luckily it is only in the area of 5-20ug
pm2.5 here

For CO2 i have been recommended this one: [https://clientmedia.trade-
server.net/1768_tfadost/media/8/00...](https://clientmedia.trade-
server.net/1768_tfadost/media/8/00/1800.pdf) which seems to measure CO2
directly.

~~~
qiqing
Do you recommend the air purifier that you have? And would you mind sharing
which one has a built-in sensor? I'd like to try measuring my laundry room.

~~~
sberder
Most purifiers on the market with built-in sensors are unreliable to measure.
They usually go for cheap IR sensors without flow control. Your results will
vary wildly depending on conditions (temperature and humidity affect
measurements a lot). I personally like Xiaomi purifiers for their
affordability and noise level.

If you're concerned about measuring pm2.5 in your space, you should consider
buying a good entry level monitor like the laser egg or air visual (acquired
by iqair not so long ago).

Don't hesitate to ask more questions, air quality had been my main business
for the past 4 years.

~~~
roel_v
Are there air quality meters available at affordable prices (say, <= $100)
that can easily be integrated with home automation systems? (like, have an
api, or that connect to cloud services so that I can capture the traffic?)
Also, any recommendations on outdoor sensors? There have been a few crowd
sourced efforts over thale last few years, but I've not been very impressed by
them.

~~~
sberder
I don't know of any cheap outdoor sensors, they are more tricky than indoor as
wind (air flow in the sensor), temperature, humidity and dust become more of a
prominent problem. For a cheap sensor, laser egg publishes API endpoints to
get latest data. You can also fairly easily add a plantower to an
arduino/raspi kind of setup. Pantower is a sensor that will give you reliable
output OOTB, can be improved but good enough.

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clumsysmurf
Its probably worse that it looks

"Researchers from Queen Mary University of London have found that people
exposed to air pollution levels well within UK guidelines have changes in the
structure of the heart, similar to those seen in the early stages of heart
failure."

[https://www.sciencedaily.com/releases/2018/08/180803103315.h...](https://www.sciencedaily.com/releases/2018/08/180803103315.htm)

~~~
sundvor
That's interesting.

We're looking at moving our son to a new school that's right at the corner of
two major artery roads in Melbourne, with some 17 000 vehicles passing daily
(just on one of them) according to VicRoads. The building doesn't appear to
have a HVAC/filtration system. Playground is behind the building, but still
has significant back traffic and is inside of 100-300 metres from the main
roads.

I'm saying that the fumes from the cars and trucks could likely have long term
health impact, but struggling to convince wife of this - she says if it was
that dangerous, then why wouldn't someone have done something about it? I must
clearly be paranoid.. ?

Personally, even though the small school appears otherwise excellent, I'm
loath to expose him to these fumes.

I seem to have acquired an ability to taste them whilst on my bicycle commute,
and will don a Respro mask when riding the streets with the most backed up
traffic.

~~~
sberder
You should be concerned as many research shows:

* leaving close to a busy road raises the risk of early dementia [1]

* higher risk of asthma

* cardiac arythmia

I could go longer but don't want to get too dark

For your situation, I think a laser egg from kaiterra is a good machine, you
can bring it around and is reliable on the long run. They use a plantower
sensor (mentioned in another comment) but have their own firmware on to
interpret the readings. I know the founder of kaiterra personnaly so I might
be biased but I'm not the only one in the industry recommending it for home
use. The laser egg 2 is also measuring TVOC but is a bit more expensive, you
might want to look into that. Overall a good and reliable machine for this
price.

You would also like to consider PM10 in Australia, from memory, the dryness of
the country and heavy farming in certain areas was producing a lot of bigger
particles.

You can also track public data on sites like aqicn.org [2] or openAQ [3]
(though the data looks sparse for Australia there).

[1]
[https://www.thelancet.com/journals/lancet/article/PIIS0140-6...](https://www.thelancet.com/journals/lancet/article/PIIS0140-6736\(16\)32399-6/fulltext)

[2]
[http://aqicn.org/map/#@g/-37.8328/144.8348/11z](http://aqicn.org/map/#@g/-37.8328/144.8348/11z)

[3] [https://openaq.org/#/map?_k=ej77x9](https://openaq.org/#/map?_k=ej77x9)

~~~
sundvor
Great response, thanks very much. That's interesting how it's also been linked
to cardiac arrhythmia! I'm unable to order a Laser Egg from (no Australian
distributors), so would need to source an alternative - unless I go for a
freight forwarder.

~~~
sberder
You could simply contact them, they're a bunch of good people, I'm sure they
could make it work for you!

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b_b
I'd recommend anyone who would like to clean the air of the home to use
products from SmartAir [1] which is as inexpensive as just a fan attached to a
filter, both of which they sell (although you can just buy the filter by
itself and attach it to a fan you already own). I visited their office in
China and received a complementary filter, which when installed in my hotel
room in Beijing, definitely cleared the air and there was a noticeable
difference from such a simple mechanism. Recommended for both price and
effectiveness.

[1] =
[https://smartairfilters.com/cn/en/?r=global](https://smartairfilters.com/cn/en/?r=global)

~~~
staikken
I've worked for a company that measures PM2.5 in the past. Using a HEPA filter
to remove PM2.5 seems unlikely to me. Perhaps there's something more going on
here than I've picked up from a quick skim of the site (perhaps there's some
sort of cyclonic separation happening) but I'm skeptical this is actually
removing particulate at that scale.

~~~
sberder
I'm not sure I get what you're saying here, HEPA is a standard that was
developed for medical environments & clean rooms [1]. To qualify as HEPA, a
filter should be able to remove 99.97% of particles 0.3µm and above so it is
definitely impacting PM2.5 (particles 2.5µm and below).

See my other comment [2] for my opinion on smartair solutions.

[1] [https://en.wikipedia.org/wiki/HEPA](https://en.wikipedia.org/wiki/HEPA)
[2]
[https://news.ycombinator.com/item?id=17720802](https://news.ycombinator.com/item?id=17720802)

~~~
staikken
I was under the impression that the filtration efficiency by particle size for
such a filter was not a linear relationship.[0] So manufacturing to a lower
bound of 3 may not say much for particles even slightly smaller. My estimation
of the magnitude of this effect may be off however as this company seems to
suggest.

[0][https://www.globalspec.com/learnmore/manufacturing_process_e...](https://www.globalspec.com/learnmore/manufacturing_process_equipment/filtration_separation_products/hepa_filters_ulpa_filters)

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coconut_crab
I have always wondered what is the relationship between PM2.5 measurement and
humidity/dew point. From what I have read all three types of PM2.5 sensors
(beta ray, particle counting...) can't tell the difference between dust
particles and water droplet. Googling around gives me a lot of conflicted
answer[1][2][3].

If one looks at the air quality graph of my city[0], it can be seen that
summer has much better AQI while winter/spring are worse. But I feel summer is
much more dustier and spring is cleaner because the street is always wet from
drizzle (dust is prevented from floating in the air). Maybe it has something
to do with the lower dew point during winter/spring as my city has very high
humidity, from 60% to 100% (right now it is 90%).

[0] [http://hanoiair.de/en_US/](http://hanoiair.de/en_US/)

[1]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4555266/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4555266/)

[2]
[https://www.ncbi.nlm.nih.gov/pubmed/29063278](https://www.ncbi.nlm.nih.gov/pubmed/29063278)

[3]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4072227/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4072227/)

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elektor
Does anyone have experience with buying an air quality sensor for personal
use? I know of Plume and AirBeam but have not seen them in use.

~~~
oh_sigh
I have this one and it works quite well:
[https://www.amazon.com/gp/product/B071RF6B2Y](https://www.amazon.com/gp/product/B071RF6B2Y)

I compared it with a friends much more expensive device, and the results were
within 5% of each other.

~~~
sonofblah
None on Amazon appear to have overall high ratings.

There's probably opportunity in the space for someone who can create an
effective, reasonably-priced model.

~~~
oh_sigh
Agreed. I was concerned about ordering mine based on the reviews, but after
looking at a lot of reviews, it is because people didn't read the manual(or,
couldn't understand it's Chinglish). The actual product itself works well
though, and the readings were within a few percent of my friends Fluke
985(~$5k particle counter - because he is a HVAC professional).

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mikeyouse
Does anyone have a sense of where the damage is done regarding PM? I live in
SF and our apartment is a block away from a busy road and a gas station, both
of which concern me. Not to mention the wild fires of late depositing ash all
over our yard.. Also, being a SF apartment, there isn't A/C so we leave the
windows open on hot days.

Is there data around whether an active air filter running in a closed room
before we go to sleep will help? Should it just run constantly? Is there any
good method to actually lower the amount of PM I'm inhaling?

~~~
jonathankoren
Purpleair.com has a map of of sensors that update in near real time you can
look at.

~~~
mturmon
That is a cool site. I had not known there was such an extensive sensor
network out there.

One thing to remember about the kind of location the parent comment wrote
about: particulates are very local. Trace gases like O3 or CH4 can have very
sharp spatial gradients - e.g., near highways, major streets, or dairy farms.
You can observe sharp decreases from emission levels to background levels
within 10s of meters. And PM2.5 mixes even more poorly than these trace gases,
meaning PM2.5 shows sharper gradients.

So, if you live in a built-up area and you really want to find out about PM2.5
due to your open window, or on your patio or backyard, you may need a very
close-by measurement.

You will still observe correlations between health outcomes and mean PM2.5
within, say, one 1km^2 monitoring footprint versus an adjacent footprint. So
the background level is definitely telling you something.

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alfozan
Air Quality Monitors Comparison:
[https://explorables.cmucreatelab.org/explorables/air-
quality...](https://explorables.cmucreatelab.org/explorables/air-quality-
monitor-tests)

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darkhorn
Enable your location in Android and then google "air pollution". It will show
air poluttion in your area.

~~~
rcMgD2BwE72F
Or don't tell Google your position continuously and just type "air pollution
<city>"

