Hair has long been considered a less-than-glamorous subject for scientific research - but for researchers studying lead exposure, it's a valuable tool that holds secrets to the past.
A recent study published in PNAS analyzed hair clippings from individuals in Utah dating back to 1916, providing a unique window into lead levels over the past century. The findings are stark: before the creation of the Environmental Protection Agency (EPA) in 1970, lead levels were about 100 times higher than they are today.
The researchers used mass spectrometry to analyze the hair samples, which revealed a significant decrease in lead concentrations following the establishment of EPA regulations. In fact, the study found that peak levels of 100 parts per million (ppm) fell to just 10 ppm by 1990 - and have remained below 1 ppm ever since.
This dramatic decline mirrors the decreases in lead emissions from gasoline, which were also phased out in response to EPA regulations. The researchers argue that the lessons of history are clear: environmental regulations have had a profoundly positive impact on public health.
"This is not just a coincidence," said Thure Cerling, a co-author of the study and biology and geology professor at the University of Utah. "The regulations have been crucial in reducing lead exposure and mitigating its effects on human development."
The study's findings come as environmental regulations face funding cuts, including a 54% reduction in the EPA's budget this year. The researchers are urging policymakers to prioritize environmental protection and recognize the importance of regulations in safeguarding public health.
While blood tests would provide more direct insight into lead exposure, hair samples offer a valuable proxy for long-term exposure trends. And as the study shows, it's clear that lead levels have declined dramatically over the past century - all thanks to the hard work of researchers like those behind this study and the EPA regulations they championed.
As Diego Fernandez, another co-author of the study, noted: "Hair records the original value of lead exposure, but the longer the hair has been exposed, the higher the concentrations become." In other words, the past holds lessons that can inform our actions today - and help protect future generations from the toxic effects of lead.
A recent study published in PNAS analyzed hair clippings from individuals in Utah dating back to 1916, providing a unique window into lead levels over the past century. The findings are stark: before the creation of the Environmental Protection Agency (EPA) in 1970, lead levels were about 100 times higher than they are today.
The researchers used mass spectrometry to analyze the hair samples, which revealed a significant decrease in lead concentrations following the establishment of EPA regulations. In fact, the study found that peak levels of 100 parts per million (ppm) fell to just 10 ppm by 1990 - and have remained below 1 ppm ever since.
This dramatic decline mirrors the decreases in lead emissions from gasoline, which were also phased out in response to EPA regulations. The researchers argue that the lessons of history are clear: environmental regulations have had a profoundly positive impact on public health.
"This is not just a coincidence," said Thure Cerling, a co-author of the study and biology and geology professor at the University of Utah. "The regulations have been crucial in reducing lead exposure and mitigating its effects on human development."
The study's findings come as environmental regulations face funding cuts, including a 54% reduction in the EPA's budget this year. The researchers are urging policymakers to prioritize environmental protection and recognize the importance of regulations in safeguarding public health.
While blood tests would provide more direct insight into lead exposure, hair samples offer a valuable proxy for long-term exposure trends. And as the study shows, it's clear that lead levels have declined dramatically over the past century - all thanks to the hard work of researchers like those behind this study and the EPA regulations they championed.
As Diego Fernandez, another co-author of the study, noted: "Hair records the original value of lead exposure, but the longer the hair has been exposed, the higher the concentrations become." In other words, the past holds lessons that can inform our actions today - and help protect future generations from the toxic effects of lead.