I know from attending some state health department lectures about lead pollution that there are still some risks, especially for young children, mainly with lead paint from old houses. There is testing where contamination is suspected. Water supplies are also tested. Lead is also an air pollutant that may be a component of the smoke of combustion. The famous Flint, Michigan, water fiasco, where a new water source was tapped that happened to be able to leach lead from networks of lead water pipes, made replacement of those pipes a huge priority that continues today in many cities. The phasing out of leaded gasoline was a major factor in reducing lead pollution. Lead from improper lead-acid battery recycling is an unnecessary problem in some places.
An article by Good News Network
summarizes the lead issue:
“Lead is a dangerous neurotoxin that accumulates in
human tissues and is linked to developmental deficits in children. Due to the
health risks, the United States and other countries start phasing out lead in
the 1970s, with the US achieving total elimination for on-road vehicles by 1996.”
They note that the last country to
stop using leaded fuel was Algeria in 2021. Combustion smokestacks, metals smelting,
paint, water pipes, and exhaust emissions are all sources of lead pollution.
Researchers at the University of
Utah analyzed hair samples from before and after regulations were enacted.
“We were able to show through our hair samples what the
lead concentrations were before and after the establishment of regulations by
the EPA,” said University of Utah Professor Ken Smith.
“Back when the regulations were absent, the lead levels
were about 100 times higher than they were after the regulations.”
The hair samples showed that after
the Nixon administration enacted rules against leaded gasoline levels as high
as 100 parts per million (ppm), before the rule was enacted dropped to 10 ppm
by 1990. In 2024, those levels were less than 1 ppm.
The paper, published in the
proceedings of the National Academy of Sciences (PNAS), shows the hair sampling
data and conclusions.
In light of recent moves to
deregulate pollutants by making higher levels acceptable or stopping any
lowering of pollutant thresholds, the current study can be seen as a clear
indication of the success of environmental regulations.
The hair samples were collected
from people living in Utah’s ‘Wasatch Front’, which historically experienced
heavy lead emissions from industrial sources. Hair samples from the same people
before and after the rules were enacted confirm the reduction in environmental
lead. Some participants were even able to find ancestors’ hair preserved in
family scrapbooks dating as far back as a century. That particular area of Utah
had a long, thriving metal smelting industry that heavily contributed to lead
pollution.
Good News Network gives some more
details:
“The research team ran the hair samples through mass
spectrometry equipment and says the surface of the hair is special.”
“Lead is not lost over time,” said research team member
Professor Diego Fernandez. “It is concentrated and accumulated in the surface.
It tells you about that overall environmental exposure.”
“Before the 1970s, gasoline contained around two grams
of lead per gallon, which added up to nearly two pounds of lead per person a
year released into the environment.”
“It’s in the air for a number of days and it absorbs
into your hair. You breathe it and it goes into your lungs,” explained Prof.
Cerling.
“But, thanks to federal regulations, the median blood
lead level today in children, aged 1–5 years, fell from over 15 in the late
1970s to just 0.6 in 2020.”
References:
Lead
Pollution Has Dropped 100-Fold in the U.S. Over the Last Century. Good News
Network. February 7, 2026. Lead
Pollution Has Dropped 100-Fold in the U.S. Over the Last Century
Lead
in archived hair documents a decline in lead exposure to humans since the
establishment of the US Environmental Protection Agency. Thure E. Cerling,
Diego P. Fernandez, and Ken R. Smith. Proceedings of the National Academy of
Sciences (PNAS). Vol. 123 | No. 6. February 2, 2026. Lead in archived hair
documents a decline in lead exposure to humans since the establishment of the
US Environmental Protection Agency | PNAS
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