In the 1920s, car manufacturers began adding lead to gasoline to reduce engine wear. Because of this, dangerous metal began to enter the air through exhaust gases and poison people. Children are the hardest hit by pollution, as lead interferes with brain development.
American scientists conducted a study to find out how much lead exposure affected local residents. The result was disappointing – according to their calculations, the problem affected almost 170 million people living in the United States in 2015. They were all exposed to lead as children, causing the collective IQ of the entire nation to drop by 824 million points, or about 3 points for each individual. Children of the 60s had the worst of all – scientists found a decrease in IQ by an average of 6-7 points in them.
To be honest, I was shocked. And when I look at the numbers, I’m still shocked, although I was ready for such a result.
Michael McFarland, sociologist at Duke University
The problem with lead is aggravated by the fact that this metal was actively used in almost all spheres of life in the last century, including construction and paints. Many water pipes in the US still contain lead and poison people. One of the most famous cases occurred in Flint, Michigan. From 2014 to 2016, water with lead entered the city water supply, which led to the poisoning of almost 12,000 children and the death of 12 people from Legionnaires’ disease.
There is no lead-added gasoline left in the world today.