In Mother Jones, Kevin Drum looks at an interesting bit of data from the 1800s:
Here’s the background. Homicides increased dramatically between 1900-11, but most of that appears to be the result of increased rural homicides, not urban homicides. If lead exposure is part of the reason, it would mean that rural areas were exposed to increasing levels of lead about 20 years earlier, around 1880 or so. But why? Nevin suggests that the answer to this question starts with another question: Why are barns red?
Professional painters in the 1800s prepared house paint by mixing linseed oil with white lead paste. About 90% of Americans lived in rural areas in the mid-1800s, and subsistence farmers could make linseed (flaxseed) oil, but few had access to white lead, so they mixed linseed oil with red rust to kill fungi that trapped moisture and increased wood decay. Red barns are still a tradition in most USA farming regions but white barns are the norm along the path of the old National Road. Why?
….The reason the red barn tradition never took root along that path is likely because the National Road made freight, including white lead, accessible to nearby farmers. USA lead output was a relatively stable 1000 to 2000 tons per year from 1801-1825, but lead output was 15,000 to 30,000 tons per year from the mid-1830s through the mid-1860s after the completion of the National Road.
….The first American patent for “ready-mixed” paint was filed in 1867; railroads built almost 120,000 track miles from 1850 to 1900; and Sears Roebuck and other mail-order catalogs combined volume buying, railroad transport, and rural free parcel post delivery to provide economical rural access to a wide variety of products in the 1890s.
The murder arrest rate in large cities was more than seven times the national homicide rate from 1900-1904 because lead paint in the 1870s was available in large cities but unavailable in most rural areas. The early-1900s convergence in rural and urban murder rates was presaged by a late-1800s convergence in rural and urban lead paint exposure.
