# Historical pollution levels **URL:** \ **Category:** Factual Questions\ **Created:** [June 21, 2008, 11:37pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732 "2008-06-21T23:37:05Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![Zyada](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zyada/32/3028_2.png) [@Zyada](https://boards.straightdope.com/u/Zyada)\ **Post date:** [June 21, 2008, 11:37pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/1 "2008-06-21T23:37:05Z")
I was having a discussion about pollution with a friend at work and said something about the health problems associated with it. He stated that it isn’t as polluted now as it used to be (he said “50 years ago”). When I said it was worse now, he wouldn’t believe me because you could see the pollution in the past, and it can’t possibly be more polluted now because you don’t see as much pollution. He mentioned seeing pictures showing how dirty the air used to be. I decided that at this point, logic alone wasn’t going to help, so I need hard facts. Does anyone have data regarding different types of pollution, and how prevalent these pollutants are now vs. in the past? Also, where can I find statistics on population levels, car ownership and the like? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 21, 2008, 11:43pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/2 "2008-06-21T23:43:25Z")
For certain pollutants - for example: Lead, Mercury, DDT, Asbestos, and Radioactive isotopes (and probably most automobile exhaust pollutants), it’s much less polluted today than it was in the past. So, you need to define what type of pollution you are talking about. ---
**Author:** ![NinetyWt](https://avatars.discourse-cdn.com/v4/letter/n/cc9497/32.png) [@NinetyWt](https://boards.straightdope.com/u/NinetyWt)\ **Post date:** [June 21, 2008, 11:45pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/3 "2008-06-21T23:45:27Z")
It would also be helpful to note what part of the planet you are talking about. Or, if you mean the entire planet. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [June 22, 2008, 1:42am UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/4 "2008-06-22T01:42:45Z")
Back 100-200 years ago, when large houses had a dozen or so chimneys, all belching the wastes from coal or wood fires, the amount of soot in the air was much higher than today. Especially in the poorer (downwind) parts of large towns, like the Eastend of London. However, you need to take into account the specific types of pollution, and the problems it causes, to decide if it was ‘worse’ then or now. ---
**Author:** ![Zyada](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zyada/32/3028_2.png) [@Zyada](https://boards.straightdope.com/u/Zyada)\ **Post date:** [June 22, 2008, 3:21am UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/5 "2008-06-22T03:21:00Z")
[QUOTE=NinetyWt] It would also be helpful to note what part of the planet you are talking about. Or, if you mean the entire planet. [/QUOTE] Let’s restrict this to the U.S. ---
**Author:** ![Zyada](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zyada/32/3028_2.png) [@Zyada](https://boards.straightdope.com/u/Zyada)\ **Post date:** [June 22, 2008, 4:18am UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/6 "2008-06-22T04:18:04Z")
[QUOTE=t-bonham@scc.net] Back 100-200 years ago, when large houses had a dozen or so chimneys, all belching the wastes from coal or wood fires, the amount of soot in the air was much higher than today. Especially in the poorer (downwind) parts of large towns, like the Eastend of London. However, you need to take into account the specific types of pollution, and the problems it causes, to decide if it was ‘worse’ then or now. [/QUOTE] I suspect that you could get into GD territory as to whether one pollutant is worse than another, which is why I am looking for statistical data, rather than value judgments. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [June 22, 2008, 4:37am UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/7 "2008-06-22T04:37:20Z")
[QUOTE=Zyada] I decided that at this point, logic alone wasn’t going to help, so I need hard facts. Does anyone have data regarding different types of pollution, and how prevalent these pollutants are now vs. in the past? [/QUOTE] The [Clean Air Act](http://usinfo.state.gov/journals/itgic/0605/ijge/holmstead.htm) of 1970 has in general been a success. Levels of most pollutants have gone down very substantially in the past 40 years. As the chart in the link shows, there have been drops in the levels of carbon monoxide, sulphur dioxide, particulate matter, volatile organic compounds, and lead. > [@](#): > > Under the Clean Air Act, the Environmental Protection Agency (EPA) has focused on six key air pollutants that have a significant impact on public health and the environment: ozone, particulate matter, carbon monoxide, nitrogen dioxide, sulfur dioxide, and lead. Since President Nixon signed the 1970 Clean Air Act, emissions of these pollutants have been cut by more than half-from 273 million metric tons of annual emissions to 133 million metric tons. The reductions for individual pollutants are just as impressive. Over the same period, emissions of lead decreased 98 percent, volatile organic compounds (contributors to ground level smog) 54 percent, carbon monoxide (CO) 52 percent, sulfur dioxide (SO2) 49 percent, and nitrogen oxides (NOx) 24 percent. I grew up in New York City in the 1950s and 1960s. Subjectively speaking, pollution appeared to me to be far worse then than it is now. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [June 22, 2008, 4:37pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/8 "2008-06-22T16:37:43Z")
[QUOTE=Zyada] I decided that at this point, logic alone wasn’t going to help, so I need hard facts. Does anyone have data regarding different types of pollution, and how prevalent these pollutants are now vs. in the past? [/QUOTE] Your OP seems to be predicated on the assumption that you are right and your friend wrong. As others have said, for many pollutants this is simply not the case. There are far more stringent controls on air pollution today than there were 50 years ago. But you need to define the question really. ---
**Author:** ![casdave](https://avatars.discourse-cdn.com/v4/letter/c/c6cbf5/32.png) [@casdave](https://boards.straightdope.com/u/casdave)\ **Post date:** [June 22, 2008, 5:09pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/9 "2008-06-22T17:09:23Z")
Today does not begin to compare when you look at local pollution, ie on a national scale. In the UK we actually have some fish in some of the rivers passing through industrial towns, we do not get the old ‘pea souper’ smogs that would kill tens of thousands every year. The controlled dumping of various wastes is very much better, sewage effluent is far better controlled, there is far less lead and other heavy metals around now than in the past, and there is very much less acid rain. Even the damage to the ozone layer appears to be abating. ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [June 22, 2008, 6:19pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/10 "2008-06-22T18:19:13Z")
There was a time when the London fog would _kill you_, as in the Great Smog of 1952. So for certain values of yes, yes pollution used to be worse. ---
**Author:** ![Zyada](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zyada/32/3028_2.png) [@Zyada](https://boards.straightdope.com/u/Zyada)\ **Post date:** [June 22, 2008, 6:27pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/11 "2008-06-22T18:27:43Z")
[QUOTE=Colophon] Your OP seems to be predicated on the assumption that you are right and your friend wrong. As others have said, for many pollutants this is simply not the case. There are far more stringent controls on air pollution today than there were 50 years ago. But you need to define the question really. [/QUOTE] I’m not understanding how “Does anyone have data regarding different types of pollution, and how prevalent these pollutants are now vs. in the past?” Is not an adequately defined question. Especially when I later restricted this to the US. ---
**Author:** ![jimmmy](https://avatars.discourse-cdn.com/v4/letter/j/73ab20/32.png) [@jimmmy](https://boards.straightdope.com/u/jimmmy)\ **Post date:** [June 22, 2008, 7:54pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/12 "2008-06-22T19:54:21Z")
The Chesapeake Bay is cleaner today than it was at its low point ~ [1983](http://www.cbf.org/site/DocServer/SOTB_2006.pdf?docID=6743) (pdf best chart pg. 11). It is roughly as clean today as it was about 1960 - before the Clean Water Act but also before the absolute explosion of development along the shore. ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [June 22, 2008, 8:18pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/13 "2008-06-22T20:18:40Z")
Certain cities have worked very hard to improve their rivers and such - you might want to eat a fish you caught in the Allegheny or the Monongahalia these days. This is partly, however, due to the death of manufacturing in the US and therefore the drop in blue collar jobs. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 22, 2008, 8:28pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/14 "2008-06-22T20:28:51Z")
Point of comparison: When automobiles were new, one of their selling points compared to horse-drawn vehicles was that, unlike horses, cars don’t pollute. Clearly, there’s less pollution in the form of horse manure now than there once was. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [June 22, 2008, 8:56pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/15 "2008-06-22T20:56:04Z")
Several years ago Scientific American did a report on air quality in the Los Angeles Basin over the years. The conclusion was that the air is measurably better now than it was in the 1960s when pollution controls started coming on line. ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [June 22, 2008, 9:03pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/16 "2008-06-22T21:03:26Z")
[QUOTE=Chronos] Point of comparison: When automobiles were new, one of their selling points compared to horse-drawn vehicles was that, unlike horses, cars don’t pollute. Clearly, there’s less pollution in the form of horse manure now than there once was. [/QUOTE] Also, when a car dies in the middle of the road, it smells better than a horse in the same circumstance. ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [June 22, 2008, 9:06pm UTC](https://boards.straightdope.com/t/historical-pollution-levels/453732/17 "2008-06-22T21:06:17Z")
[QUOTE=Rick] Several years ago Scientific American did a report on air quality in the Los Angeles Basin over the years. The conclusion was that the air is measurably better now than it was in the 1960s when pollution controls started coming on line. [/QUOTE] As anybody who lives in the Greater LA basin can tell you. It was much, much worse in the 60s and 70s. It still _looks_ ugly when the smog rolls past Ontario, but that is just cosmetic. The real poisons are at much lower levels these days.