How much air pollution is due to cars?

Cars have fueled the growth of the modern world, and they've also been responsible for an enormous amount of pollution. But how much air pollution is really due to cars? Scott and Ben give you the stats.

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Episode Transcript

Speaker 1 (00:00):
Go behind the wheel, under the hood and beyond with
car stuff from how Stuff works dot Com. All right, Ben,
so here's the scoop lay it on. The cars get
blamed for a lot of stuff. Yeah they do, and
I mean a lot of stuff. But SUVs, cars, et

(00:22):
cetera get blamed for pollution. And that's a that's a
big thing right now. You know, everybody's talking about how
how bad cars are for the environment, how bad the
big SUVs are for the environment. Um, but I guess
what it comes down to is like, well, how much
really is due to cars? Now? Much is due to
you know, the big factories. How much is due to airplanes?
How much is due to h agri business for instance, agriculture, Yeah,

(00:45):
exactly how much? I mean, how much really is coming
from automobiles? It's got Luckily, Uh, since we work at
a place to answers questions like this, I think we
might be safe to tackle this one. What are you
thinking that is fortunate that we work in a place
like that. Yeah, I think it's good. But okay, so
when we say that, when when you hear people say,

(01:09):
uh that cars are you know, emitting terrible pollutants, What
we really need to ask ourselves are first off, you know,
if you want to answer a question, first off, you
have to define the terms in the question. So we
say pollutants, what do we mean? We usually mean volatile
organic compounds. Now people have heard our stuff about the
new car smell, are familiar with these, guys? Yeah, you

(01:32):
don't recently. I mean if be listening about this or
reading about this rather. Um, those are in everything. They're
in countertops, they're in um you just yeah, they're in everything.
They're in everything that we have in our home, in
our cars. Um, they're around us right now in the studio. Uh.
These these v o c s is what they called them.
And uh really, unless you're you're making a conscious effort

(01:55):
to build or buy something that has low v o
c s, you're gonna experience these in some way daily. Yes,
So that's a that's the first hint you're getting you
being the listeners side that you Scott, that's the that's
the first hint. Um, now we're giving you guys. Uh,
when we talk about pollutioning cars and the surprising answer, Um, Now,

(02:20):
there's also other things that the cars emit aside from
the O C. Yeah, I mean there's a lot of
other things too. There's uh, there's you know, nitrogen dioxide,
there's methane that's produced. There's all kinds of things that
that you know, we call them green there's some greenhouse
gases that come out of this. Um. There's just a
lot of things that end up floating around in the

(02:41):
air that are bad for us, and those are often
called they're called particulate matter. And what that is is
it's organic material, in organic material that floats around and
it's bad for us. I mean, it's not just that
it's dust and and acids and metals like that to dirt. Um.
But really, when it comes down to, is the size
of the material that dangerous for us? Because it can't

(03:03):
be that shouldn't say it that way. I should say
that if it's smaller than a certain size, it does
get within our lungs and it does create health issues
for humans. Yes, I mean it's it's it's lung issues,
it's hard issues. Um, it just causes a variety of
problems in humans. Yeah. And that the size uh is

(03:25):
I think less than ten micrometers, which is ten micrometers
in diameter. Uh, that's the you must be this smaller
to interline for the human lungs. I'm gonna say, is
it is it micrometers? Micrometers? It sounds better, It does
sound more micrometers, micrometers. I don't know. Maybe you're right. No,
I think you're michrometer sounds like an instrument. My micrometer.

(03:48):
Micrometer sounds like an instrument. I don't know if I'm
right or not. I think I'm wrong. No, No, we'll
we'll believe me. Believe me, brother, We're gonna see. Now.
Another thing, when you asked the question how how much
what percentage of air pollution is due to cars, the
question is sort of phrase in a way that assumes
global air pollution. And one thing we need to be

(04:11):
very conscious of is that air pollution varies wildly across
the world. So so like if you're if you're in
a place where there's not where there's not many people,
where there are not many people excuse um, or if
you're in a heavy, heavily populated, heavily urbanized area, then

(04:33):
of course the pollution is going to go higher. Yeah,
we heard about that a lot during the Olympics. Right,
there was a big push about Beijing Olympics, Right, it's
a big push to to really clean the air up
before the Olympics, which I thought was kind of strange.
You know, they're just gonna do it just for that.
It seems like that would have a you know, there's
a bigger need there that you know, they need to
do it all the time. But um right, yeah, I guess.

(04:54):
I guess really congested areas that are are famous for
having poor air quality, um l A is one, and
that's a that's I think that's a geographical thing, right,
isn't that. Uh, it's it's it's locked into the region
by the mountains to the to the east. Yeah, there's
a weather conditions. That's a great point because weather conditions also,

(05:15):
from what we understand, can really make a difference in
the level of air pollution, uh that you will find
in general, not just from cars, but in general. Okay,
and then there's also regions like Beijing. I'm sure that
you know, manufacturing has a lot to do with that,
and that and lower restrictions on emissions, I guess. Um,

(05:36):
although I thought I thought for some reason, I've heard
that you know, they've really really tightened up on those,
um for automobiles, I don't know about um factories like this.
That's a cool bit of news. Yeah, I know what
you're talking about. Just recently, I think that's what you're
referring to. Uh, just recently, the Chinese government in Beijing
had started making some moves from what I understand too,

(05:59):
uh not allow people to just go in and register
a new car. You have to enter a lottery. So
that is seen as the fairest way to satisfy the
amount of people they can give registration to in a
fair way. Now, of course, a lot of people are
objecting to this. A lot of people are not bothering

(06:22):
to register their vehicles. I'm predicting. Sure, there's always a
way around this thing. There's always a way. But is
you know, is it a is it a good idea?
But so here we are, Scott, Uh, here we are, Scott,
take me through this because we've got all these variables,
We've got all these things going on. We've even heard
it said that, uh, cattle produce massive amount I'm glad

(06:44):
you mentioned that because I didn't know you're gonna bring
that up. But I do have we have we have
an article on our site about that. Believe it or not,
Believe it yeah, I mean it's it's it's funny title.
And we had actually talked about doing this as its
own podcast at one point, I remember. But the the
article's title, do cow was polluted as much as cars?
And it turns out that cows give off an incredible

(07:04):
amount of methane gas every day. Um, it's a greenhouse
gas and uh, let's see it's um. Well boy, some
experts believe that um through well through belgian and through
flatulence at the other end. Uh. They believe that they

(07:24):
give off as much as one hundred two hundred liters
a day um, while others say is it's as high
as five hundred liters a day and that's about a
hundred and thirty two gallons a day in either case. So, um,
that's an awful lot of pollution produced by cows. That's
that's far more than a car would produce of methane
of that particular pollutant. Yeah, let's be careful with that

(07:48):
because that's just methane. So that's one pollutant. And the
reason for that is just the the complex digestion system
that a cow has going on with four stomachs, and uh,
you know what do they call that there's a there's
a certain type of reticulates. Yeah, that's right, ruminant. Yeah. Yeah,
and that's where they digest the food. They they moves
through the four change exactly exactly. They regurgitated and they needed.

(08:12):
It's gross the whole system, but um, but that's that's
the way it works in it and it leads to
a lot of bacteria that produces this methane. So cow
is just naturally belch and and well whatever. Yeah, they
just hang out. Yeah, they create a lot of methane
in factor, a lot more than cars. But um, when
we're talking about air pollution, we're talking about like we said,

(08:34):
you know the other um, other greenhouse gases as well
as you know, just other pollutants that that they expel. Yeah,
so um, you want to just give him the number
here and just kind of uh yeah, let's do it now.
You know, I don't like this number. Why because I
think this number is got a wide margin. Yeah, yeah,

(08:55):
I think you're right. Okay, So here's here's the uh,
here's the prediction. Okay. So this is from the e
p A. And you know they've got loads of smart scientists, uh,
and loads of brilliant scientists even and according to the
e p A, motor vehicles produced roughly one half of

(09:15):
the pollutants like VOCs, nitrogen oxide, and particulate matter UM
one half. Roughly one half. I can believe that because
there there are a lot of cars, you know. Um,
but then we've got kind kind just go to the
statistic that I disliked the most. Okay, in urban areas, uh,

(09:36):
auto emissions are responsible from anywhere between fifty and ninety
percent of air pollution. That is a wide gap. That's crazy.
You could drive a you could drive a hummer through
that gap. That's right. That is a that's a big gap.
I don't know how they get between fifty and air pollution,
but um, I don't know. I mean they kind of

(09:56):
did kind of all lump it together in urban areas.
So they could be small town USA and uh and
here in Atlanta. It could also be very densely populated
but very um green trending places like some like a
northern European metropolis and versus you know, a place that

(10:17):
has no emissions laws. Sure, yeah, this could be. I
mean that's probably the reason for this this wide gap here. UM.
One other statistic they point out is that sev of
carbon oxide emissions come from automobiles. So carbon oxide that's
another it's not a greenhouse gas, I don't believe, UM,
but that is another. UM it's a it is a

(10:38):
harmful polluting it's a harmful pollutant, of course, but UM
it's just another um biproduct of you know, burning fossil fuels,
and and that's what we're talking about here. That's it's
it's uh, it's part of air pollution. I guess if
you want to go that route with it. UM. So, yeah,
these numbers, I mean, they're they're kind of startling to me.
I didn't think it was as high because I thought, um,

(10:59):
I really thought that production would get a higher you know, um,
manufacturing would get a higher percentage than automobiles would in
some of these situations. But yeah, it is. It is
very surprising because I honestly did not think it would
be as much either, especially considering, as you said, industry,

(11:19):
but also considering that, you know, agribusiness itself does play
a role in that, especially when you're involved with you know,
the methane manufacturers that are cowls. Well, there's also also
the thing that you know, like there's been a lot
of advancement's made on automobiles that have reduced pollution. Uh,
catalytic converters is one greatest seventies fuels. That's right, there's

(11:43):
fuel sensors, I mean because right now, you know, it
used to be used to be able to adjust how
your car ran rich or Lean with a screwdriver and
your garudge. Now you don't do that. Now it's computer
controlled and it's it's done instantaneously and auto adjusts. Yeah, exactly.
So there's there's the advancement you know that you know,
you don't have people righting around that had the cars
way out of tune um because they tried to do

(12:05):
it in a garage or whatever. Um. So you know,
it seems like it seems like most cars now would
be running a lot um I guess cleaner, and I
know that they are, but there's just so many of them,
I think, And it comes down to volume. Yeah, and
there's so many. That's that's where you see there's so
many more people buying cars each year, especially with the

(12:30):
rise and quality of living for a lot of people
in developing countries and the drop in price that we're
seeing in some in some vehicles. Now. One of the
ways that manufacturers of things like the Tata Nano, which
is the world's cheapest car currently, right, Um, some of
the things that they do to bring the price down
make it worse for the environment. I mean, catalytic converters

(12:53):
honestly cost money. So these sometimes the motivation isn't there,
you know, the urge to be the urge to pay
a premium per vehicle based entirely on environmental concerns is
something that is not near as common in places where
people are buying the first car their families owned. That's true. Yeah,

(13:16):
they're they're more motivated by just the idea of having
the freedom of an automobile, uh, not having to know,
crowd six people onto a motorcycle and drive somewhere. Um yeah,
I think I think your your point is valid. I
think that you know, they're they're more concerned with just
getting a cheap vehicle out there that they can they
can market as being safe. And when you which I

(13:39):
don't know in some cases and maybe not so much
when you see what what's out there, but um, you know,
emissions falls to the bottom of the list. Sure, and
let's take that one anecdote we made and multiply it
several magnitudes, so we have hundreds of millions of people
doing this. UM. But I think one thing we are

(14:00):
going to see that reduces air pollution UM or maybe
mitigates this. You know how much gas is now in
the UK. I couldn't even guess. I'm gonna get Okay,
I'll guess close to six dollars, right, you're almost it's
a little bit closer to nine. No way, I'm hearing

(14:22):
now this has variation, you know, UM for people who
don't know about in the US. Uh, the U S situation. Uh,
that's more than twice. Yeah, what we're right around three
right now, and they're promising that it's going to go
up significantly in the near future. So um man nine dollars, yeah, yeah,

(14:43):
nine dollars, Oh my gosh. And the idea six pounds
I think I'm not I'm not sure on the currency
pectures in there. Someb O right and but yeah, but
that fluctuates. But still you know a lot of we've
talked before about how um, A lot of other countries
do have heavier taxes on on their gas per per

(15:04):
leader or per gallon, and so that might be one
of that's probably one of the big factors. But it's
also something that US consumers UH need to prepare for. Honestly,
maybe not in the near future, but in the midst
of long term we are going to see UM permanently
higher priced gas UM, probably with higher taxation on it

(15:27):
to combat air pollution or encourage people to drive less UM.
But for right now, Yes, s carbon monoxide one half
of the really nasty pollutants with complicated names. And you know,
I wish I that's one thing I wish I had
with me here and I don't. I meant to bring
in a list of um the greenhouse gasses uh and

(15:50):
I I failed to do that, and that's why I
think early on we might have mentioned something that I'm
not sure method rather our greenhouse gasses methode is. But UM,
I just wish I had that listen in front of me.
I don't. Maybe we can get that for an upcoming podcast,
because UM, when you hear the list of what is
and what isn't you you might be surprised. I mean,
it's some of them that here lumped in together oftentimes aren't. Yes,

(16:13):
that's a good point, and we not all, not all
are from automobiles, by the way, No we're not so. Yeah,
show we're not going to fuilify. Way off track here,
we should we shouldn't continue. No, No No, we've got so
I hope that. I feel like we've maybe given people
the lay of the lands here. Oh, somebody, let's go
ahead and pre empt this guy. Somebody's going to write

(16:35):
in and say, what about hybrid and electric vehicles? Okay,
so here's the deal with those, and and correct me
if I'm wrong. Um, the deal with hybrid and electric
vehicles is that, yes, they're widely popular. More and more
people are coughing up the scratch to buy them. However,

(16:56):
going from nothing to wildly popular is still a fair
ways away from becoming statistically significant. Yes, but I mean,
am I right on that? Yeah? That's right. And hybrid
vehicles still use fossil fuels. Um, electric vehicles in most
cases still use fossil fuels. Yet because of the election,
you know, energy production, we've talked about this and I

(17:18):
wouldn't you know another thing I wish I had. I
got a couple of pieces of listener mail recently about
hybrid vehicle resale value. Oh yeah, I had some good Oh, Yeah,
there's there's some there's some issues going on with hybrid
resale value, so I'll bring those in soon. There's some shenanigans.
Just you guys know. It's definitely Scott speaking of air pollution.

(17:41):
I have to get out of here and go on
a road trip kind of thing. Oh very good. Um,
but where should know about? Um? Well, I want to.
I want you to have plausible deniability. Man, I don't
want to. I don't want to get you in trouble
that I never heard anything. But I do feel that
an next change for your confidence, for takeing, for taking

(18:02):
you into my confidence and trusting you with my secret
road trip, I owe you at least the last word
on air pollutioning cars. Oh boy, okay, well I guess
the last word. Really, let's say that, Um, I know
that they're guilty, but I still love cars and and
I think that you know, it's funny, you know, we

(18:24):
we talked about how SUVs are getna blame for a
lot of pollution, and there everybody was kind of a
witch hunt for a while, right, Yes, most definitely. Um,
it seems to me that there's still a lot of
trucks and SUVs out there is still being built. People
still love these cars, and it seems that fuel cost
is driving this whole thing. It really does. I mean,
when the fuel costs are down, people are buying the

(18:45):
bigger cars. When the fuel costs go up, everybody's screaming
for hybrids. I just really think I think that's what
it all comes down to. Ben, I don't think that
really people are going to give up that the big
suv in the in the driveway until prices go up.
Like we talked about, UM, as far as you know
the blame for something like this, I'd say, keep watching
the numbers because you're gonna find better and better tests

(19:07):
that are coming out. And I think that you can
find manufacturing and things like that are gonna be more
responsible for air pollution than what people are giving them
credit for right now. UM, I don't know. I'm I
feel like I'm I'm defending cars here where people are
gonna say that's not really the way it is. You know,
there there are numbers that point to this, but just
keep watching, keep watching, Well said, I don't know. I

(19:30):
don't know. I think it was it was eloquent. I
think that what what you're saying is not so much
the ramblings of a madman. Hey, I try to take
my medication before I get I'm talking about you. I'm
a little late on medication right now. No, okay, well
you know what that means before Scott as an episode,

(19:50):
No kidding, another episode then, uh, we're gonna go ahead
and get out if you're We hope that we have
given you, guys, m some good stuff to think about,
and we hope that you will be as interested in
this as we are because, uh, my co host here
is absolutely right. Um, the tools that we use to

(20:13):
measure these numbers are evolving and as a result, we
may have different calculations in the future, which means we
have to follow up. Seems they're always updated, numbers, always
always And if you want to give us an update,
you like that one, Scott, Sure, And I expect there's
gonna be a lot on this one, because whenever you
talk about pollution, you talk about numbers, you talk about

(20:34):
the amount of pollutants in the air or whatever. Yeah,
somebody's gonna call up with with with a different opinion,
which we love. Yeah, we'd love to hear from you.
As a matter of fact, will help you find us.
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(20:58):
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