mother jones has a fascinating and detailed report on lead being the hidden villain behind violent crime, lower IQs, and even ADHD with discussion of new research that builds on earlier work ( from 1999?!) which concluded that gasoline lead may explain as much as 90 percent of the rise and fall of violent crime over the past half century. all that great reporting and only passing mention is made to aviation gasoline which is the largest source of lead emissions in the U.S., accounts for half of the lead pollution in american skies and is not planned to be phased out until 2023.