> Between 3.64 and 6.84% of phenotypic intelligence (as measured by the VNR Test in UK Biobank) could be predicted (Supplementary Table 10); the upper limit is an improvement of ~43% on the largest reported estimate to date, of 4.8% [16].
Doesn't 7% seem quite small (though better than previous studies)? What am I missing?
Malnutrition and serious physical abuse aren't the only environmental factors with a known significant impact on intelligence, and nutrition (particularly childhood nutrition) patterns with a serious adverse effect on IQ have been identified in research focussed on first world areas of study; they certainly aren't rate enough to be insignificant sources of variation in the first world.
Overall exposure is lower, sure, that doesn't mean it is insignificant in impact on IQ (and other health issues, notably cardiovascular disease.)
No, lead exposure from water systems, unabated older housing, continued use of leaded aviation fuel, and other sources continues to be a nontrivial issue in the US and some other parts of the first world.
https://www.ncbi.nlm.nih.gov/pubmed/2628311
https://www.sciencedaily.com/releases/2004/11/041117005027.h...