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It's been suggested that the removal of lead from fuels, paints, etc. may explain the fact that our IQs have risen since about the same time, and since leveled

It's been suggested that the removal of lead from fuels, paints, etc. may explain the fact that our IQs have risen since about the same time, and since leveled off somewhat. http://en.wikipedia.org/wiki/Flynn_effect http://en.wikipedia.org/wiki/Flynn_effect Say what you will about environment, but the lead explanation seems to match historical data in all the ways we'd expect it to. Find something that lead does, and we find a trend showing its decline since we started eliminating lead.

api 12y ago
I wonder how this interacts with IQ differences by ethnicity, given that historically some ethnic groups tended to live in inner cities where lead exposure would have been significantly greater.
- thaumasiotes 12y ago
  This has been studied. Gains from the Flynn effect don't show a relationship to race effects in IQ.
ern 12y ago
Reading the Wikipedia article seems to indicate that most of the rises in IQ due to the Flynn effect happened during the period when fuel lead levels were high. Would they have risen faster without lead?
gretful 12y ago
Speaking of historical data: leaded plumbing is linked to the decline of the Roman Empire.
- shabble 12y ago
  Are there reliable sources on that? Also, using Lead Acetate[1] as an artificial sweetener probably didn't help matters. [1] https://en.wikipedia.org/wiki/Lead%28II%29_acetate#Sweetener https://en.wikipedia.org/wiki/Lead%28II%29_acetate#Sweetener
  - gretful 12y ago
    Here's a good place to get started: http://penelope.uchicago.edu/~grout/encyclopaedia_romana/wine/leadpoisoning.html http://penelope.uchicago.edu/~grout/encyclopaedia_romana/win... although this argues that lead in plumbing was NOT a major source of poisoning.
- aliakbarkhan 12y ago
  [citation needed]
- Panoramix 12y ago
  This is debunked here: http://www.reddit.com/r/AskHistorians/comments/23o92d/on_cosmos_neil_degrassetyson_said_some_historians/ http://www.reddit.com/r/AskHistorians/comments/23o92d/on_cos...

api 12y ago

I wonder how this interacts with IQ differences by ethnicity, given that historically some ethnic groups tended to live in inner cities where lead exposure would have been significantly greater.

thaumasiotes 12y ago
This has been studied. Gains from the Flynn effect don't show a relationship to race effects in IQ.

ern 12y ago

Reading the Wikipedia article seems to indicate that most of the rises in IQ due to the Flynn effect happened during the period when fuel lead levels were high. Would they have risen faster without lead?

gretful 12y ago

Speaking of historical data: leaded plumbing is linked to the decline of the Roman Empire.

shabble 12y ago
Are there reliable sources on that? Also, using Lead Acetate[1] as an artificial sweetener probably didn't help matters. [1] https://en.wikipedia.org/wiki/Lead%28II%29_acetate#Sweetener https://en.wikipedia.org/wiki/Lead%28II%29_acetate#Sweetener
- gretful 12y ago
  Here's a good place to get started: http://penelope.uchicago.edu/~grout/encyclopaedia_romana/wine/leadpoisoning.html http://penelope.uchicago.edu/~grout/encyclopaedia_romana/win... although this argues that lead in plumbing was NOT a major source of poisoning.
aliakbarkhan 12y ago
[citation needed]
Panoramix 12y ago
This is debunked here: http://www.reddit.com/r/AskHistorians/comments/23o92d/on_cosmos_neil_degrassetyson_said_some_historians/ http://www.reddit.com/r/AskHistorians/comments/23o92d/on_cos...