Episode 37: Lead and IQ

Episode 37: Lead and IQ

Author: Tom Chivers and Stuart Ritchie May 14, 2024 Duration: 1:04:51

Petrol, pipes, paint: they made a whole generation duller. That’s if you believe the research on the effects of lead on IQ. By interfering with neurological development, the lead that we used to encounter routinely has left hundreds of millions of us with a tiny bit of brain damage.

In this episode of The Studies Show, Tom and Stuart look at the toxic effects of lead - from very obvious, high-dose lead poisoning to the more insidious, low-level effects that have apparently held millions of people back. How strong is the evidence for the effects of low-level lead exposure on IQ?

The Studies Show is brought to you by Works in Progress magazine, a journal of ideas to accelerate human progress. If you’re a student aged 18-22 and want to attend the Works in Progress “Invisible College” this August (at which Stuart is speaking), take a look at this link.

Show Notes

* Centers for Disease Control (CDC) page on lead poisoning

* Articles on the history of lead poisoning from the BBC and the Guardian

* 2022 PNAS study concluding that “half of US population exposed to adverse lead levels in early childhood” (the one with the “824,097,690” figure)

* Article on blood lead levels and which are considered dangerous

* The 2005 meta-analysis on lead and children’s IQs

* Cited in the 2021 “Global Lead Exposure Report

* The critique from the CDC in 2007

* The critique paper from 2013

* The critique paper from 2016

* The correction from 2019

* The critique paper from 2020

* Quasi experiments: from Rhode Island; using manufacturing employment

* 2018 paper on low-level lead and all-cause mortality

Credits

The Studies Show is produced by Julian Mayers at Yada Yada Productions.



This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit sciencefictionspod.substack.com/subscribe

Every week, Tom Chivers and Stuart Ritchie pull apart the biggest arguments and most confusing claims making headlines. Science Fictions isn't just about celebrating breakthroughs; it's a necessary dive into the messy, contested, and often surprising realities of how science actually works. You'll hear them unpack heated debates, examine questionable studies, and explore why even solid research can sometimes lead to public confusion. This podcast serves as a guide through the noise, separating compelling evidence from overblown narratives. Each episode feels like a conversation with two deeply informed friends who aren't afraid to ask tough questions, offering clarity on topics that matter. For anyone curious about the stories behind the science headlines, this is an essential listen. Tune in for thoughtful analysis that goes beyond the press release, grounded in a genuine fascination with how we know what we know.
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