The 20th century saw the highest rates of lead pollution in South America in nearly 2,000 years, according to a recent study.
Commissioned by the Paul Scherrer Institute of the University of Berne, the study analyzed samples from the Bolivian Illimani glacier. Scientists were able to determine that the levels of lead pollution tripled after the 1960s when leaded petrol was first introduced — a process that was supposed to make cars more efficient, though was was banned in 2014 for its poisonous health impacts. Researchers concluded that in less than 50 years, the use of leaded petrol resulted in the highest levels of lead pollution in the past two millennia.
The findings confirm the key role of policymakers in environment and pollution matters, as well as the huge impacts of motor transportation and fossil fuel use. Anja Eichler, one of the authors of the study, said:
“Our study reveals a significant drop in lead pollution levels after the ban on leaded gasoline in the region of the Bolivian Andes, although it has still not fallen to natural rates.”
Before the use of leaded gasoline, lead contamination was mainly caused by silver mines and metallurgical work. Previous studies also show a spike in lead levels in the second half of the 20th century. A 2014 paper by NASA notes that lead pollution, carried by precipitation, had reached the South Pole more than two decades before human explorers. However, the research undertaken by the Paul Scherrer Institute’ is the first to confirm the devastating effects of lead pollution caused by leaded petrol in South America. As Anja Eichler notes, her team’s work “highlights the importance of the ban of leaded gasoline for the environment and human health,” and overall, the importance of policymaker intervention.