The detection of even low levels of lead in a child's blood may be an indication of emotional and behavioral problems, a new study finds.
Lead is a harmful chemical that can affect brain development. Shedding more light on this, a new study found that even trace amounts of lead in a child's blood may be an indication of emotional and behavioral problems. These problems include anxiety, depression and aggressiveness. It also lowers a child's IQ.
"This research focused on lower blood lead levels than most other studies and adds more evidence that there is no safe lead level," said lead author Kimberly Gray in a press statement. "It is important to continue to study lead exposure in children around the world, and to fully understand short-term and long-term behavioral changes across developmental milestones. It is well-documented that lead exposure lowers the IQ of children.
For the study, researchers measured blood lead concentration in more than 1,300 preschool children in China. The children were aged between 3 and 5 years. When they reached 6 years of age, researchers assessed them for behavioral issues by asking them to fill up a standardized questionnaire. The children's teachers and parents were also asked to answer some questions. Researchers found that any amount of lead concentration in the blood was associated with an increased risk of behavioral and emotional problems, such as being anxious, depressed, or aggressive.
Lead is a naturally occurring toxic metal, but lead exposure is often due to human activities, including burning fossil fuels, mining, and manufacturing. In the United States, lead exposure usually comes from lead-containing products, such as paint, caulking, and pipe solder in older homes. In China, lead exposure is more often related to air pollution.
"The sources of lead exposure may explain why concentrations of lead are different," the study authors said. "In China, we found that blood lead concentrations increased with age in preschool children. In the United States, however, blood lead concentrations increase with age in children up to 2-3 years old and then decline."
Children are particularly vulnerable to the negative effects of lead as it damages their developing nerves and brains. According to the Centers For Disease Control and Prevention, no safe blood lead level in children has been identified. Even low levels of lead in blood have been shown to affect IQ, ability to pay attention and academic achievement. What's even more dangerous is that the effects of this chemical are irreversible.
The study was funded by the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health. The results were published online in the journal JAMA Pediatrics.
