
Exposure to air pollution is linked to an increase in violent crime - pseudolus
https://www.economist.com/graphic-detail/2019/10/09/exposure-to-air-pollution-is-linked-to-an-increase-in-violent-crime
======
PeterStuer
For all those commenting on 'aren't more polluted areas just more criminal due
to other factors", as far as I can tell the researchers examined crime rates
for the _same_ place and find correlation with whether there was more Ozone
and PM 2,5 on a particular day or not.

So they are not comparing clean air neighborhoods to highly polluted
neighborhoods, but the same neighborhood on different days.

[https://www.sciencedaily.com/releases/2019/10/191003114007.h...](https://www.sciencedaily.com/releases/2019/10/191003114007.htm)

~~~
mjlee
Is there a word for the fallacy of believing that another professional didn't
consider the factor you thought of in seconds?

I see this all the time at meetup tech talks and it infuriates me!

~~~
Nasrudith
It wouldn't be a formal fallacy in itself although certainly impolite. Perhaps
like Slippery Slope.

It is related to arguement from ignorance and Dunning-Kreuger effect in that
it often assumes their comprehended issues are the end of all problems and
that the objections may already be implicitly handled. Listing everything
explicitly in exhaustive detail technically addresses it but would be both
inefficient and bad communication from how overloaded it would get.

That said assuming uncovered issues are implicitly covered is itself a
fallacious inference. It may be dickish pedantry that is wrong based upon
incomplete information but not illogical given what is known and communicated.

------
t0mek
Related: "much of the decline in crime in the 1990s may have been due to the
reduction of childhood lead exposure after the removal of lead from gasoline
and house paint."

[http://freakonomics.com/2007/07/09/lead-and-
crime/](http://freakonomics.com/2007/07/09/lead-and-crime/)

~~~
zjaffee
I absolutely believe that removing it from gasoline is a big factor, but I
think it's often over emphasized in the context of today.

Cleveland has twice the prevalence of lead paint over any other big city in
the united states, yet has 25% lower violent crime prevalence than say, st
louis, baltimore, detroit, and memphis.

~~~
anigbrowl
Lead paint tends to stay on the wall so as long as you don't eat paint chips
it's not as big a risk as particulate lead in fuel exhaust. If you are
removing lead paint you need to wear a suitable respirator to avoid breathing
in fragments but just being in a room with lead paint or a lump of the stuff
isn't especially dangerous.

------
PeterStuer
You can read the full paper directly from the author here

[https://drive.google.com/file/d/18S8Ttan33xbH2UYKY_N1EcNAYyA...](https://drive.google.com/file/d/18S8Ttan33xbH2UYKY_N1EcNAYyAsm1W0/view)

~~~
johnfactorial
My hero!

------
mnw21cam
The main problem I see with this study is that it could be confounded by the
fact that high air pollution areas have other problems too that could be
causing the bad behaviour instead, like overcrowding, noise, frustration at
slow traffic, etc.

~~~
Frost1x
Reminds me of one of the prototypical sociological study examples of
correlation vs causation where something akin to icecream sales correlated
highly with murder rates.

The fact air pollution, in many cases, directly correlates with population
density, make the results seem less surprising. It would be more interesting
if less populated areas with high air pollution (perhaps near industrial
plants, etc.) had a high correlation to violent crime rates in conjunction
with highly dense populated areas.

~~~
huffmsa
Except it's not a case of ice cream and summer time.

Lead fucks people up. Always has, always will. Pretty easy to trace a
relationship between lead concentrations and societal disfunction.

[https://en.wikipedia.org/wiki/Lead%E2%80%93crime_hypothesis](https://en.wikipedia.org/wiki/Lead%E2%80%93crime_hypothesis)

~~~
Armisael16
The article specifically mentions the lead-crime hypothesis as a different
example of hypothesized linkages between air pollution and crime. It seems
exceptionally likely that it isn’t what they’re looking at.

This paper specifically looks at short term air pollution effect (ie, the
kinds that will measurably rise and fall in different parts of a city over an
8-year span). Lead takes so long to affect a single person (since it mostly
harms brain development in children, but crimes are mostly not committed by
children) that it almost certainly being meaningfully measured here.

~~~
mirthflat83
Hacker news and not reading the article before commenting name a more classic
combination

------
macawfish
It's such a typical kneejerk "skeptical" reaction at this point to be like "oh
well maybe correlation doesn't imply causation" as if there are no causal
relationships ever in life itself.

But really if the rationalists just took a few seconds to think about it maybe
they'd find a some plausibility in the notion that exposure to harmful
pollution could trigger a stress response; stress is intimately wrapped up
with aggression.

[https://www.apa.org/news/press/releases/2004/10/feedback-
cyc...](https://www.apa.org/news/press/releases/2004/10/feedback-cycle)

~~~
BurningFrog
Well, I think it's a fact¹ that a large majority of "science" stories that go
viral turn out to be wrong.

So the rational approach to them _is_ "what might be wrong with this one?".

¹ Citation Missing

~~~
josephdviviano
If you want to avoid this, just read the paper.

I don't understand why technical people waste their time complaining about
this stuff. We all have the acumen to read, understand, and debate research.

~~~
moultano
It's paywalled.
[https://www.sciencedirect.com/science/article/abs/pii/S00950...](https://www.sciencedirect.com/science/article/abs/pii/S0095069619301901)

If I had access, I'd try to dig into more depth into how they approached
decoupling this from temperature, because that seems like a really strong
confounder. I'm also a bit curious about the underlying physical cause of the
change in pollution levels, (weekends? summertime?) because that seems like it
could also be a confounding common cause.

Alas, I'm not interested in paying $35 for the paper.

~~~
imagin8or
Preprint from the Colorado State website:

[https://pierce.atmos.colostate.edu/Monthly_Pollution_and_Cri...](https://pierce.atmos.colostate.edu/Monthly_Pollution_and_Crime.pdf)

~~~
moultano
Thanks!

------
bloak
The paper doesn't seem to be freely available; there's just the abstract. The
first sentence of the abstract mentions "short-term". So I think what they've
detected is that in a given locality people get violent when the air is dirty,
which is not surprising, of course, but it's interesting to have an estimate
of the magnitude of that effect.

One would like to know for comparison what the magnitude of the effect of
humidity and temperature is on violent crime. Those numbers are probably in
the paper somewhere because the abstract mentions how they had to "address
confounding variation between temperature and air pollution". It not being
mentioned in the abstract makes me suspect that the effect of pollution on
violent crime is probably rather small compared to the effect of weather on
violent crime.

(Is there a positive correlation between people stating stupid banalities and
violent crime? Probably there is, because people who parrot things like
"Correlation does not imply causation" tend to get punched in the face. For
the avoidance of doubt, that was a joke, not a veiled threat.)

EDIT: The last sentence of the abstract strikes me as highly questionable
(though perhaps there's something in the paper to justify it). Just because
there's a short-term correlation between pollution and violent crime doesn't
mean that there will be a long-term correlation with a similar magnitude. In
other words: if you reduce pollution globally over the next ten years people
might just raise their expectations and be just as violent on the days on
which pollution is relatively high as they were ten years previously.

------
chippy
"They are now working with a large online chess platform to determine if
increased pollution exposure is correlated with worse chess performance."

[https://scitechdaily.com/fascinating-and-scary-is-
something-...](https://scitechdaily.com/fascinating-and-scary-is-something-
literally-in-the-air-causing-violent-crime/)

------
Santosh83
Yes violence increases in animals too if the environmental stress (biotic and
abiotic) ratchets up. It stands to reason the same applies to humans although
we have more conscious control over our responses but we don't often exercise
them unless we're aware. These are all subtle mechanisms by which
destabilising effects can cascade and proliferate. This is why ecologists and
conservationists warned against unrestricted exploitation and an appeal to the
assurance of science and technology rescuing us out of the resulting mess, but
this is exactly the path we're down on.

------
0xcde4c3db
The article doesn't talk about mechanisms, but researchers have been looking
at the effects of air pollution on the brain for a while, so there are at
least some hints in the literature. My favorite specific result to cite in
this general direction, which seems potentially relevant here, is that there
is evidence that acute exposure to some forms of air pollution blunts or even
eliminates the increase in serum brain derived neurotrophic factor (BDNF;
basically a kind of growth hormone for the brain) otherwise caused by exercise
[1]. Depending on what's mediating that effect, it could be that a whole
complex of CNS regulation/recovery/maintenance mechanisms is altered by
various forms of air pollution.

[1]
[https://www.ncbi.nlm.nih.gov/pubmed/21708224](https://www.ncbi.nlm.nih.gov/pubmed/21708224)

------
jeegsy
Can someone explain what "linked to" means in the context of a research study?
Is it just a way to highlight correlation when it is insufficient to assert
causation?

~~~
PeterStuer
"linked to" is used as a synonym for "correlated with" in articles aimed at a
layman audience because they think the latter is a word that isn't part of the
layman's vocabulary.

It is debatable whether this type of presumed accommodation leads to making
the articles more accessible, or just dumbs down colloquial language further
in a perpetual spiral to the bottom.

------
imagin8or
Preprint is here:

[https://pierce.atmos.colostate.edu/Monthly_Pollution_and_Cri...](https://pierce.atmos.colostate.edu/Monthly_Pollution_and_Crime.pdf)

It points out that they look at data for 99% of US counties, which rules out a
simplistic attribution of crime to population density, and describes some of
the data cleansing. They also claim it corroborated findings elsewhere.

Since this is a data review presumably other centres can repeat the analysis
to confirm the correlation result at least, and medical researchers could
conceivably find a real experiment to establish causality.

------
fedups
I'm not sure about how much causation is being captured here, but I don't
doubt the effect directionally. Here's a paper that came to similar
conclusions, which I think captures causality better

[https://www.nber.org/papers/w25489](https://www.nber.org/papers/w25489)

Basically it compares performance of students who transferred into schools
upwind vs downwind of major highways. Unsurprisingly, those who ended up in
downwind schools saw

> decreases in test scores, more behavioral incidents, and more absences

~~~
PeterStuer
The article itself references many such studies correlating long term exposure
to polluted environments with cognitive impairment. This study however focuses
on short term effects (within the same day).

------
colordrops
I grew up in a part of the US that some of the most polluted air in the
country, back in the 70s and 80s. I recall waking up on a particularly clear
day and being shocked by a mountain in the background, not realizing how close
we lived to the mountains. I also recall feeling depressed about the
continually yellow sky. While there may be a physiological effect of air
pollution, I'm certain there is also a strong psychological effect, which
could explain the immediate effects described in the article.

------
Merrill
From the Abstract - >"We find a robust positive effect of increased air
pollution on violent crimes, and specifically assaults, but no relationship
between increases in air pollution and property crimes."
[https://www.sciencedirect.com/science/article/abs/pii/S00950...](https://www.sciencedirect.com/science/article/abs/pii/S0095069619301901)

Paywalled paper from an Elsevier journal.

------
aflessner
This could be data dredging since it seems they may have looked at lots of
dimensions and picked the one that correlated. It doesn’t make sense to me the
effect of air pollution would be so acute and at such low levels:

The effects are present in and out of the home, at levels well below Ambient
Air Pollution Standards

[https://en.m.wikipedia.org/wiki/Data_dredging](https://en.m.wikipedia.org/wiki/Data_dredging)

------
ETHisso2017
Can someone go into the paper and list out the confounding variables that the
authors accounted for?

e.g. weather (temperature and air pressure); day of week; time of year;
whether auto-related crime was tagged as "violent" crime;
ethnographics/demographics of a community (an aging community will pollute
less and be safer) etc etc

------
aflessner
This seems like data dredging to me. I would be surprised if this holds true.

[https://en.m.wikipedia.org/wiki/Data_dredging](https://en.m.wikipedia.org/wiki/Data_dredging)

------
vondur
It'd be interesting to look at data from countries that have really bad air
pollution levels and see if this trend is seen there too.

------
dwoozle
If the conclusions here are as statistically robust as they seem, why wasn’t
this published in Nature or Science?

------
neonate
[https://outline.com/Ftuxkp](https://outline.com/Ftuxkp)

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subsaharancoder
Looking forward to "The air made me do it.." defense coming soon to a court
near you

~~~
scarlac
While that sounds like a troll comment, I'm going to say that there's merit to
this - at least as a class action lawsuit. When you get sick from second hand
smoke and it's been shown to be bad for you, there's a case to be made. If
people are being psychologically affected by 'second hand pollution' then
there's a case to be made that the local or federal government isn't doing
their job (which is to serve the people). A lawsuit can be very real if
consistent results are shown in multiple studies.

------
hapidjus
More cars => More people out and about => More opportunity for crime to
happen?

------
tyingq
Lead(Pb) in the air maybe?

~~~
huffmsa
Yes. Lead moreso that other pollutants. Areas with higher concentrations of
ground lead (older, poorer parts of cities) are pretty strongly linked with
violent crime.

Pretty well documented, don't have the citations handy though. It's been
thoroughly discuss on HN.

Rudimentary citation

[https://en.wikipedia.org/wiki/Lead%E2%80%93crime_hypothesis](https://en.wikipedia.org/wiki/Lead%E2%80%93crime_hypothesis)

~~~
ljf
Interested - what would be causing the high lead levels in those areas, not
that lead has been removed from petrol? Is it legacy contaminants or other
ways that lead is released into the environment?

I was warned off eating the food I grew in my garden in London as historically
people threw their ash into their gardens, so the soil their can be pretty
polluted.

~~~
Richard_East
Lead is still present in Avgas.

~~~
dsfyu404ed
100LL is used in such vanishingly small quantities compared to basically every
other source of lead it may as well be rounding error.

Someone always brings this into any discussion of lead as though we should all
be outraged that lead isn't technically banned in all fuel.

------
mrfusion
Is there a certain chemical they think causes this?

~~~
acd
PM 2.5 are small particles from Diesel cars for example.

------
RedComet
I wonder if they took demographics into account?

------
dubliner2077
With the fog, you can hide your crimes.

------
m463
I remember reading "Sexual Assault increases as Ice Cream Sales go up".

Turns out sexual assault is less likely in the winter.

------
S-E-P
well of course.

As someone in an area with a lot of smoke, I'm much more irritable

------
downandout
This article is paywalled with no workaround. My understanding was that HN did
not allow such links. Economist.com links, if they are all hard-paywalled like
this, should be blacklisted.

~~~
dang
Users usually post workarounds in the threads. They did in this thread.

~~~
downandout
A “workaround” doesn’t mean someone posting a link to Outline or a similar
service. It means having a way to access the content on the site itself.
Economist.com links should be blacklisted, because they have no workaround. If
Outline is required to read a given article, then the main link on the
submission should go to Outline.

You seem to be stickler for the rules, so I can’t understand your position on
this.

------
codesushi42
If that is the case, why aren't major cities in China, or other major Asian
cities like Singapore bastions of crime? Hint: they aren't. They are in fact
some of the safest places in the world, and on average have air pollution
levels much higher than cities in the US, even dangerous ones!

And yet look at all of the misinformation in the comments, as usual.

~~~
schainks
There is plenty of _undocumented_ violent crime in China, like domestic
violence, for example.

~~~
kebman
That's like saying that there's undocumented crime on the moon. You don't know
that. But you have a theory that you most likely need more funding to look
into. ;) On the other hand, if you have documentation to the contrary, I'll of
course retract my own claim.

------
kashishgrover
Oh Delhi

------
kebman
Everyone sing with me now: "Correlation does not imply causation!" :D

~~~
kebman
You guys seriously need to lighten up...

------
partyboat1586
Textbook correlation vs causation.

------
cy6erlion
What if violent crime is the cause of air pollution.

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vojta_letal
Is not there some common denominator, something simple like - there is both
more crime and pollution in cities?

~~~
alkonaut
I'd like to assume that all the "easy" facors are already taken into account
(population density, property value, education level, income level, weather,
etc).

Even if it's just a correlation, it's not really a result worth publishing
otherwise.

~~~
vojta_letal
I do not get why it got downvoted. Maybe I should have elaborate more. I
skimmed the paper and it does not seem to be the case. They only take into
account weather.

------
koolba
Could this be as simple as people with asthma being less able to evade the
perpetrators?

------
yalogin
It just doesn’t make sense intuitively to me. This feels more like an example
to show correlation does not equal causation. So what if the violent crime is
higher in highly polluted areas? How is that information useful for anything?

~~~
bulletsvshumans
Well, for starters, it might incentivize governments that want to reduce crime
to reduce pollution.

------
m3kw9
Another correlation, is it coincidence as in urban city usually has high
pollution and high crime or a real link like pollution causes brain to go
violent?

------
whatitdobooboo
They think people who have enough to not have to resort to crime will live in
dirty areas by choice?

------
4lch3m1st
That's one dishonest headline. Air pollution areas are commonly associated
with big cities, where the crime rate tends to be higher. The website clearly
turned this into something else for no reason at all other than clicks.

~~~
paggle
Ironically, your accusation of them doing this for "the clicks" prevented you
from clicking the link and finding out that your criticism is not relevant to
this study.

