You Smelled It Every Shift for Twenty Years. The WHO Calls It a Group 1 Carcinogen.

Some workplace hazards announce themselves. A trench collapses, a machine catches a sleeve, a barrel spills. Diesel exhaust doesn't. It is the smell of a locomotive idling in a yard, a line of trucks at a dock, a forklift running inside a warehouse in January with the doors shut against the cold. It is so ordinary that most of the men and women breathing it think of it as part of the job rather than as an exposure.

The World Health Organization's cancer agency does not think of it that way.

What changed in 2012

The International Agency for Research on Cancer — IARC, the WHO body that evaluates whether substances cause cancer in humans — had classified diesel engine exhaust since 1988 as probably carcinogenic to humans, its Group 2A category.

On June 12, 2012, IARC reclassified diesel engine exhaust as carcinogenic to humans — Group 1, its highest category, the one that holds asbestos and benzene. The working group concluded there was sufficient evidence that diesel engine exhaust causes lung cancer in humans, and limited evidence of an increased risk of bladder cancer. The decision rested heavily on studies of workers exposed on the job — including a large study of miners and a study of the trucking industry — rather than on laboratory animals.

That reclassification is the single most important fact for a worker with an occupational-exposure history and a lung cancer diagnosis, and most people have never heard of it.

Who breathes it in Nebraska

This is a rail state, a trucking state, a warehousing state and a farming state, which is another way of saying it is a diesel state. The exposures I hear about most often come from:

• Railroad work — engine and yard crews, shop and roundhouse mechanics, and anyone who spent years around idling locomotives in enclosed or poorly ventilated spaces.
• Trucking and terminals — dock workers, mechanics, and drivers who idled for hours at loading bays.
• Warehouses and distribution centers — propane and diesel forklifts run indoors, especially when the building is buttoned up in winter.
• Heavy equipment and construction — operators and ground crews around excavators, generators and compressors, and anyone working in a tunnel, pit, or other confined space with an engine in it.
• Farm and grain operations — tractors, dryers and trucks running in and around enclosed buildings.

None of that is exotic work. It is the work this region runs on.

What a claim actually looks like

Here is what I tell people who call after a diagnosis, and I want to be straight about it: an IARC classification establishes that a substance can cause cancer in humans. It does not establish what caused cancer in any one person. That is a medical question, answered by physicians who look at your exposure history, your smoking history, your genetics, and the type and location of the tumor. A lawyer who tells you otherwise before reading a single record is selling something.

What a lawyer can do is build the record those physicians need — and that work is entirely about reconstructing a working life. Which yards, which shops, which years, which engines, what ventilation, what respiratory protection was offered, what the employer knew and when. Employers change names, plants close, and personnel files get purged, which is why reconstructing a decades-old exposure history is the real craft in these cases.

The other threshold question is which system your claim lives in. Railroad workers generally do not go through workers' compensation at all — their claims run under FELA, a federal statute with a very different structure, which is also why railroad toxic exposure cases follow their own path. A warehouse worker, a mechanic, and a truck driver may each be in a different posture again, depending on who employed them and who controlled the air they breathed.

Why bring it to me

Toxic exposure cases are won by whoever is willing to do the archaeology — old union records, coworker affidavits, plant layouts, equipment histories — and then put a credible scientific story in front of a defense that would rather talk about cigarettes. That is work I do, and I have taken it as far as it needs to go. My clients have recovered more than $23 million, including a $5.4 million result, and they describe what that fight was like in many five-star reviews. My firm was voted Best of Omaha for personal injury law in 2025 and 2026.

If you or someone in your family worked years around diesel engines and has been diagnosed with lung or bladder cancer, talk to a Nebraska toxic exposure lawyer before the records get any older. Call me at (402) 378-9208 or reach out here. The consultation is free, and there is no fee unless I win.

Frequently asked questions

What did IARC decide about diesel exhaust in 2012?

On June 12, 2012, IARC reclassified diesel engine exhaust as carcinogenic to humans — Group 1, its highest category, the one that holds asbestos and benzene. The working group concluded there was sufficient evidence that diesel engine exhaust causes lung cancer in humans, and limited evidence of an increased risk of bladder cancer.

Who breathes diesel exhaust at work in Nebraska?

This is a rail state, a trucking state, a warehousing state and a farming state, which is another way of saying it is a diesel state. The exposures I hear about most often come from railroad work, trucking and terminals, warehouses and distribution centers, heavy equipment and construction, and farm and grain operations.

Does the IARC classification prove diesel exhaust caused my cancer?

An IARC classification establishes that a substance can cause cancer in humans. It does not establish what caused cancer in any one person. That is a medical question, answered by physicians who look at your exposure history, your smoking history, your genetics, and the type and location of the tumor.

Do railroad workers bring diesel exhaust claims through workers' compensation?

Railroad workers generally do not go through workers' compensation at all — their claims run under FELA, a federal statute with a very different structure. A warehouse worker, a mechanic, and a truck driver may each be in a different posture again, depending on who employed them and who controlled the air they breathed.

Your Attorney

Frank Younes

Every page on this site is written by Frank Younes, a Nebraska trial attorney with a published record of verdicts and settlements, selection to the National Trial Lawyers Top 100, and a practice that covers every county in Nebraska and Iowa. No case is handed to an associate — the lawyer you read here is the lawyer who works your case.

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