Research from regions as diverse as the Arctic and Aegean is helping scientists understand how industrial activity has impacted the environment over the last 5,000 years and continues to do so today.
For example, a study published last year in Science of The Total Environment shows how per- and polyfluorinated alkyl substances (PFAS) persist, accumulate and pose threats to Arctic biodiversity and humans.
The study demonstrated that long-range transport and reactions affect PFAS chemical profiles and levels in the Arctic. The research revealed that PFAS accumulates most heavily in mammalian liver tissue and seabird eggs. Notably, polar bears appear to be more vulnerable to the harmful effects of these chemicals than humans.
The authors say that monitoring of legacy and novel PFAS across the entire Arctic region, plus proactive community engagement and international restrictions on PFAS production remain critical to mitigate exposure to them and their health impacts.
There is sufficient evidence from the Arctic, they conclude, to phase out production and use of PFAS worldwide.
Similarly, a study in the Dec. 10, 2024, issue of Environmental Science & Technology describes how researchers from Spain, Sweden, Norway and the UK detected 36 PFAS around the Arctic island of Spitsbergen from January–August 2019 (i.e. moving from a period of 24 hours of total darkness to 24 hours of complete daylight). Their findings indicated widespread and chemically diverse contamination, including at remote high elevation sites.
In fact, at one such site, PFAS deposition was up to 71 times higher during periods of 24-hour daylight. This, the researchers say, means that seasonal light is important to enable photochemistry for PFAS atmospheric formation and subsequent deposition in the Arctic.
This study provides the first evidence for the possible atmospheric formation of PFAS from precursors, they add.
Lead's Historical Legacy
Meanwhile, going back 1,000 years or so, fallout from lead pollution caused by silver smelting during the Roman Empire could have lowered the IQ of the European population by 2–3 points, according to a study published Jan. 6 in the Proceedings of the National Academy of Sciences.
Led by a team from the Nevada-based Desert Research Institute (DRI), the researchers analyzed three ice cores from the Arctic that spanned the era of the Roman Empire — roughly 500 BC to 600 AD (Figure 1).
Their findings suggest air lead concentrations exceeded 150 ng/m3 near smelters, with average enhancements of >1.0 ng/m3 over Europe during the empire’s peak.
The result was widespread cognitive decline.
According to the research, more than 500,000 tons of lead was released to the atmosphere during the nearly 200-year height of the Roman Empire.
The lead found in Arctic cores rose again during the Middle Ages, taking off during the Industrial Revolution and peaking before leaded gasoline started being phased out in the 1970s.
“As lead pollution has declined during the last 30 years, it has become more and more apparent to epidemiologists and medical experts just how bad lead is for human development,” said Joe McConnell, research professor of hydrology at DRI and lead author of the study.
The Jan. 30 issue of Communications Earth & Environment went back another several thousand years to examine the history of pollution.
Geoscientists from Heidelberg University in Germany have found lead contamination in the Aegean region from about 5,200 years ago. That’s 1,200 years before the previously earliest known evidence of environmental contamination with the heavy metal that is traceable to human activity, they say.
The research team analyzed 14 sediment cores from the sea floor and coastal regions surrounding the Aegean Sea, plus one from a peat bog.
Their findings chart a transition from agricultural to monetary societies and the impact this had on the environment.
Analyses of pollen found in the cores pointed to intense deforestation at the time, too. Greeks and later their Roman conquerors used wood as fuel to smelt silver, gold and other metals.
Modern Day Implications
The EPA and the Centers for Disease Control and Prevention are unequivocal when it comes to lead: It’s toxic, persistent and can bioaccumulate in the body over time.
Young children, infants and fetuses are particularly vulnerable to the heavy metal, exposure to which can lead to behavior and learning problems, lower IQ and hyperactivity, slowed growth, hearing problems and anemia. In rare cases, says the EPA, ingestion can cause seizures, coma and even death.
Meanwhile, the EPA added nine more PFAS to its Toxic Release Inventory on Jan. 3, bringing the number listed so far to 205.
