By John Salak –
U.S. cars haven’t been leaded gasoline since 1996 when Bill Clinton was president, Bob Dole was Senate Majority Leader and Ross Perot was running around trying to launch the Reform Party. Oh yeah, the Chicago Bulls were NBA champions, Jerry McGuire and The English Patient were the big movie blockbusters of that year.
Long time ago, right? Yeah, but the lingers and harmful effects of leaded gas is still being felt by 170 million Americans to this day, at least according to research put out by Duke University and Florida State University. A new study from these universities claims that car exhaust from leaded gas during childhood stole a collective 824 million IQ points from about half the current population of the United States. The findings warn that Americans born before 1996 may now be at greater risk for lead-related health problems, such as faster aging of the brain.
Leaded gas was introduced in 1923 and usage peaked in the 1960s and 1970s before it was eventually banned. The researchers noted that this put people at particular risk who were exposed to these high leaded fumes as children during peak usage periods. There is no safe level of exposure to lead, which is neurotoxic, for anyone at any point of life. Young children, however, are especially vulnerable to its ability to impair brain development and impact cognitive functions.
“Lead can reach the bloodstream once it’s inhaled as dust, or ingested, or consumed in water,” warned Aaron Reuben, a PhD candidate at Duke who worked on the study. “In the bloodstream, it’s able to pass into the brain through the blood-brain barrier, which is quite good at keeping a lot of toxicants and pathogens out of the brain, but not all of them.”
Not surprisingly, automotive exhaust was one major avenue for lead to get into bloodstreams. The research team arrived at its cumulative impact of leaded gas by relying on public data on U.S. childhood blood-lead levels, leaded-gas use and population statistics. They crunched this data to determine the likelihood of lifelong impact of every American alive in 2015, which included the loss of IQ points. “I frankly was shocked,” reported co-author Michael McFarland of Florida State. “And when I look at the numbers, I’m still shocked even though I’m prepared for it.”
The bottom line is that highly exposed individuals are now at greater risk of health issues, such as reduced brain size, greater likelihood of mental illness and increased cardiovascular disease as adults. It also means that the country as a whole lost 824 million IQ points—nearly three points per person. Those individuals born in the mid-to-late 1960s may have lost six points on average. Three to six points may seem negligible, but the research team explained that these lost points for some individuals could shift them from below-average cognitive ability (less than 85 IQ points) to being classified at having an intellectual disability (IQ scores under 70).
Effectively, this is a hidden and lingering burden. “Millions of us are walking around with a history of lead exposure,” Reuben said. “It’s not like you got into a car accident and had a rotator cuff tear that heals and then you’re fine. It appears to be an insult carried in the body in different ways that we’re still trying to understand but that can have implications for life.”
