Bonus Article: This article complements our 4-part mini-series on unintended consequences in environmental action. It explores a parallel case: the removal of lead from gasoline and what came next.
In the mid-20th century, the removal of lead from gasoline was widely heralded as a landmark public health success—and for good reason.
Lead exposure, especially in children, was linked to irreversible brain damage, lower IQ, behavioral issues, and a host of neurological effects. By phasing out tetraethyl lead (TEL), governments around the world dramatically reduced blood lead levels and improved health outcomes for millions.
It was, and still is, viewed as one of the great environmental victories of the modern era.
But here’s the thing: that’s not the end of the story.
What Came After the Lead?
When TEL was removed from gasoline, it left a problem behind: how to maintain octane levels in fuel without causing engine knocking.
The solution? A group of petrochemicals known as aromatics—specifically benzene, toluene, and xylene, collectively referred to as BTEX compounds.
These chemicals did the job.
They kept engines running smoothly and fuel efficient.
But they also introduced a new class of health risks—ones that didn’t receive nearly the same public attention.
The Quiet Trade-Off
BTEX compounds are volatile organic compounds (VOCs). They’re known to:
- Contribute to ground-level ozone and smog formation
- Cause respiratory issues, headaches, and fatigue
- Include benzene, a known human carcinogen
- Have neurotoxic effects, particularly with long-term exposure
Unlike lead, these compounds don’t bioaccumulate in the body in quite the same way, but they’re inhaled regularly in urban environments—especially near roads, gas stations, and heavy traffic.
So while the visible harm of lead was removed, a less visible but still significant risk was introduced.
Did We Really Fix the Problem?
This isn’t to say we should’ve kept lead in gasoline. Clearly, it had to go. But it raises an uncomfortable question:
Did we simply substitute one toxic solution for another—because it was easier than redesigning the system?
Much like sulfur in ship fuel, the removal of lead didn’t happen in a vacuum. It disrupted an industrial process that had been propped up by dangerous chemistry for decades.
Instead of reimagining how engines could be designed to run cleaner, we found a chemical workaround. One with its own consequences.
Are We Still Doing This?
This pattern of substitution over transformation shows up again and again.
We remove the obvious villain—then quietly replace it with a lesser-known alternative that may turn out to be just as bad. A few examples:
- BPA was removed from plastics after concerns about hormone disruption—only to be replaced with BPS, which may carry similar risks and still leaches into food and water.
- PFOA, a key chemical used to make non-stick coatings like Teflon, was phased out due to its links to cancer, liver damage, and its classification as a “forever chemical.”
It was replaced by GenX—not a generation, but a trade name for a new PFAS chemical.
GenX was promoted as a safer alternative. But growing evidence shows it too is toxic to the liver and kidneys, may cause cancer, and is persistent in the environment, showing up in drinking water and rain. - Sulfur was removed from ship fuel for air quality reasons—but in doing so, we may have lifted a veil that had been holding back the full warming effects of climate change.
Each of these “solutions” solved a problem in the short term. But they also created or uncovered new risks we weren’t prepared for.
A Pattern Worth Breaking
The removal of lead was a massive win—but the silence around what replaced it is part of a larger issue: we don’t always follow the full chain of consequences. We declare victory at the first visible outcome and rarely ask what happens next.
If we want to truly solve environmental and public health problems, we need to:
- Look beyond the immediate fix
- Question what comes after the solution
- Understand that the absence of headlines doesn’t equal safety
A Companion Cautionary Tale
Just like sulfur’s removal exposed our reliance on a pollutant to cool the climate, the shift from leaded gasoline to BTEX compounds raises a similar question:
Did we solve a problem, or just change its shape?
We meant well.
And we did better.
But maybe—we could go deeper still.
This article complements our 4-part series, When Clean Gets Complicated, which explores the unexpected environmental impacts of sulfur reduction in shipping fuel.
In this series:
- ✅ The Law of Unintended Consequences
- ✅ When Cleaner Isn’t Simpler
- ✅ What If Our Environmental Fixes Backfire?
- ✅ We Meant Well: But Did We Forget to Ask the Right Questions?
🔎 Bonus: From Lead to BTEX – Did We Trade One Toxin for Another? – You are here!
Further Reading – From Lead to BTEX
The Guardian – “Legacy of toxic leaded petrol lingers in air in London, study finds”
URL: https://www.theguardian.com/environment/2021/jun/21/legacy-of-toxic-leaded-petrol-lingers-in-air-in-london-study-finds
This article discusses how, despite the ban on leaded petrol, its toxic legacy persists in London’s air, highlighting the enduring environmental impact of past fuel choices.
Environmental Health Perspectives – “Environmental exposure to benzene: an update”
URL: https://ehp.niehs.nih.gov/doi/10.1289/ehp.961041129
This comprehensive review examines the sources and health effects of environmental benzene exposure, emphasizing its prevalence and the associated risks to human health.
The Guardian – “Firms ‘knew of leaded petrol dangers in 20s’”
URL: https://www.theguardian.com/environment/2000/jul/13/uknews
An investigative piece revealing that major companies were aware of the dangers of leaded petrol as early as the 1920s but continued its use, underscoring corporate negligence in public health.
Environmental Health Perspectives – “Benzene toxicity and risk assessment, 1972-1992”
URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1520014/
This article provides an in-depth analysis of benzene’s toxic effects and the evolution of risk assessment methods over two decades, highlighting the challenges in regulating this hazardous chemical.
The Guardian – “Leaded petrol era ‘officially over’ as Algeria ends pump sales”
URL: https://www.theguardian.com/environment/2021/aug/30/leaded-petrol-era-officially-over-as-algeria-ends-pump-sales
Reporting on the official end of the leaded petrol era with Algeria ceasing its sale, this article reflects on the global efforts to eliminate this toxic fuel and the health benefits anticipated.
Books:
While comprehensive books specifically focusing on both the phase-out of leaded gasoline and the adoption of BTEX compounds are limited, there are several authoritative works that delve into the history, science, and policy decisions surrounding these topics. Here are some notable recommendations:
The following books are linked to Amazon.com for your convenience. If you decide to purchase through these links, we may earn a small commission — at no extra cost to you.
Invention and Innovation: A Brief History of Hype and Failure [amazon.com]
Author: Vaclav Smil
Description: This insightful book examines various technological advancements and their unintended consequences, including a discussion on the adoption and subsequent phase-out of leaded gasoline. Smil provides a critical analysis of the economic and environmental factors that influenced these decisions.
Superfuel: Thorium, the Green Energy Source for the Future [amazon.com]
Author: Richard Martin
Description: While primarily focused on alternative energy sources, this book touches upon the historical context of fossil fuels, including the use of leaded gasoline, and explores the search for safer and more sustainable alternatives.
Lead Wars: The Politics of Science and the Fate of America’s Children [amazon.com]
Authors: Gerald Markowitz and David Rosner
Description: This book explores the public health crisis caused by lead poisoning, including the role of leaded gasoline, and examines the political and scientific battles that ensued over its regulation.
Deceit and Denial: The Deadly Politics of Industrial Pollution [amazon.com]
Authors: Gerald Markowitz and David Rosner
Description: This investigative work uncovers the history of industrial pollution in America, with a focus on lead and vinyl chloride, detailing how industries concealed the dangers of their products, including leaded gasoline.
These books provide valuable insights into the complex history of fuel additives, environmental health, and the unintended consequences of industrial innovations.
Image Acknowledgement
We’re grateful to the talented photographers and designers on Unsplash for providing beautiful, free-to-use images. The image on this page is by Olga Gryb. Check out their work here: https://unsplash.com/@grybdesigns/illustrations.
