JAMA: People who grew up in the era of leaded gasoline more than 30 years ago have shown a decline in IQ in middle age...

Thirty-four years ago, a group of children growing up in lead-contaminated environments were included in the study.
now, these middle-of-life people have been found to have subtle but significant changes in brain structure... In a recent study published in the Journal of the American Medical Association (JAMA), an international team of researchers led by Duke University in the United States found that exposure to lead from childhood led to higher blood lead levels associated with lower IQ in middle age and decreased body volume in the sea mass.
sea mass plays an important role in memory, learning and emotion.
blood lead level is the amount of lead in the blood.
it is well known that lead is a very harmful substance to human body.
It can enter the body through breathing or skin, affect the nervous system, interfere with the central nervous system signal transmission, destroy the enzyme processing zinc, iron and calcium and other nutrients, make people have consciousness disorders, and so on, thus affecting the normal functioning of the human body.
normal blood lead level is 0-99 micrograms per liter.
study, researchers using an MRI found that participants who grew up in high-dose lead at age 11 had significant changes in their brains at 45.
, blood lead levels drop by an average of 2 points by age 45 for every 5 micrograms per litre higher.
their brain cortical surface area was also 1.19 square centimeters less, the hippo horse body was 0.1 cubic centimeters smaller, and the hippopial body played an important role in memory, learning and mood.
with the highest levels of blood lead also showed structural defects in the brain's whiteness, which is responsible for communication between regions of the brain.
participants themselves reported no cognitive loss, but those close to them noted that they tended to have small problems with memory and attention in their daily lives, such as being distracted or misplacing things.
, lead study lead author and PhD student at Duke University, said: "We found that after decades of exposure to lead, there were significant defects and differences in the overall structure of the brain.
important because it helps us understand that people can't fully recover from lead exposure in childhood.
fact, more serious problems may arise over time.
All of our brain measurements were based on previous associations with age-related cognitive decline and cognitive abilities," said Maxwell Elliott, a Doctoral Student at Duke University and co-lead author of the study.
areas of the cerebral cortical layer are most closely related to cognitive function.
"s study, from a 34-year study of 1,037 people born in the same town in New Zealand in 1972 and 1973, has been on the study ever since.
, 997 participants are still alive, 564 of whom have been tested for blood lead.
the study, researchers obtained data on lead exposure in childhood for 564 participants who grew up at the peak of leaded gasoline in the late 1960s and late 1980s.
, as was the case in other developed countries at the time, almost all people were exposed to lead levels higher than they are now allowed.
gasoline, refers to the car gasoline added a certain amount of four ethyl lead gasoline.
china has banned the production of leaded gasoline nationwide since January 1, 2000.
July 1, 2000, all gas stations nationwide stopped selling and using leaded gasoline.
, a professor of psychology and neuroscience at Duke University, explains: "This involves macro-features of the brain as a whole.
we start by looking at these features of the brain, because researchers don't really understand the relationship between lead exposure in children and later brain development.
now, differences do exist.
"Elliott" said: "This may reflect the long-term consequences of lead exposure, as the surface area of the cerebral cortical layer, hippocta volume and white mass structure all grow in childhood and peak in early adulthood."
"reuben said, "there will be more differences as people get older."
It may be too early for this well-studied group of middle-aged New Zealanders, and what I finally want to know is whether people who were exposed to lead as children face a higher risk of degenerative diseases as they reach old age."
animal studies have shown that exposure to lead early in life can lead to brain changes that lead to degradation, such as changes in gene expression patterns and poor vascular health.
but Reuben says it hasn't been seen yet.
。