Plumes of jet black smoke belch from the truck’s oversized, bed-mounted exhaust port, as the driver hangs out the window, taunting the environmentally friendly commuter cars stuck at the stoplight around him. The light turns green and the rig jumps off the line, sending clouds of smoke and soot spewing into the open air. A cyclist unfortunate enough to be downwind of the truck wretches from the fumes, as an elderly gentleman in a vintage British convertible shakes his head in disapproval, as he slaps his MG into gear, and turns onto the on-ramp. 

This is but one of countless examples of how the trend of “rolling coal” has become a staple of the modified diesel truck scene, the automotive equivalent of flatulently “crop dusting” those around you. Modded diesel rigs are more popular than ever before in America, and it appears that most states really don’t give a damn about what these vehicles are spewing from their exhaust ports.

But this is more than just about pickup trucks with massive exhaust ports. Recent reports have found that diesel exhaust is responsible for more deaths than previously predicted, and it’s kids and the elderly that are in the most danger. Here’s what we know…

Photo Credit: Diesel truck addicts/Facebook

Smoke ’em if Ya Got ’em

The United States Environmental Protection Agency (EPA) reports that a combination of lax laws and shoddy enforcement from law enforcement officials has allowed the proliferation of diesel trucks with disabled emissions controls to grow exponentially over the course of the past few years. Compounding the matter, is the fact that most people have become so used to this trend, that reports are very rarely filed in states where rolling coal is illegal.

Don’t get us wrong, we love us some diesel power here at AvalonKing, and we appreciate how modern diesel motors have become more than just an engine with a torque-rich powerband. Take Mazda for instance, which in recent years has begun putting its “SkyActiv D” engines into many of its vehicles. Heralded for having “the world’s lowest diesel-engine compression ratio,” Mazda’s 2.2-liter twin-stage turbo motor offers tons of torque all the way up to 5200 rpm, and is surprisingly quiet. In stock form, this motor not only delivers impressive performance numbers, but can be run indefinitely without the need for expensive NOx (nitrogen oxide) after-treatment chemicals.

But not everyone is rocking a diesel-powered Mazda or the latest EcoDiesel RAM pickup. From freight trains and ferries, to farm equipment, school buses, and 4×4 vehicles, diesel engines are the modern world’s workhorse. A motor for the masses, with a dark side that goes well beyond rolling coal and emissions defeating systems.

Photo Credit: Toxic Performance/YouTube

What’s So Fucking Dangerous About Diesel?

Before we get too deep into all things diesel, let’s talk a bit more about the oh-so American art of “rolling coal,” and how this polluting pastime is having an adverse effect on air quality. In order to grasp the extent of this soot-rich modified truck trend, one must reference the aforementioned letter from the EPA’s Air Enforcement Division. 

Within this document, you will find that in the past decade alone, over 550,000 diesel pickup trucks either had their emissions controls tampered with or removed entirely. Over the course of the lifetime of these trucks, this will translate to the atmosphere being saturated with more than 570,000 tons of additional nitrogen oxide (NOx), as well as 5,000 tons of particulate matter. To put these numbers into perspective, imagine what your commute would look like with over 9 million additional, non-tampered diesel pickup trucks on the road… every… damn… day. 

For decades, we’ve known that airborne pollutants can be lethal, yet here we are, discussing America’s deeply rooted infatuation with producing excessive amounts of diesel exhaust, just for shits and giggles. Looking to learn a bit more about what makes this form of fuel so toxic, we unearthed a paper focusing on the dangers of diesel released by the United States government’s Occupational Safety and Health Administration (OSHA). After sifting through numerous scientific jargon inlaid pages, it became apparent that OSHA’s report painted a fairly grim picture of the gunk suspended within diesel exhaust smoke. 

We start with some of the more common chemical offenders found within diesel exhaust, like carbon dioxide, carbon monoxide, nitrogen dioxide, nitric oxide, and sulfur dioxide, all of which are extremely harmful if inhaled. Oh, and let’s not forget polyaromatic hydrocarbons (PAH), the common organic carbon compound found in diesel exhaust that has been known to cause cancer and reproductive harm. Extended exposure to these, and many more chemicals within diesel exhaust, has been linked to health defects ranging from irritation of the eyes and nose, to headaches and nausea, and in extreme cases, respiratory disease and lung cancer.

Diesel smoke also contains things like our old friend formaldehyde, which a separate OSHA report finds has been linked to everything from “asthma-like respiratory problems,” to skin irritation and death. Benzene is another common carcinogenic chemical found in diesel exhaust, which according to the CDC, can harm bone marrow and cause anemia due to a sudden drop in red blood cells. There’s also the risk of excessive bleeding and compromised immune system functions when exposed to benzene for lengthy periods of time, so don’t assume that it won’t kick you while you’re down. 

Photo Credit: NRDC/Facebook

Suffice to say, states with strict vehicle inspections and heavily enforced emissions standards have the least amount of exhaust spewing modified diesel trucks, with California leading the way with just 1.8% of its vehicles being reported. In contrast, North Dakota remains one of America’s least regulated states, and therefore over 18.6% of all diesel trucks on its roadways either have had their emissions systems tampered with or removed completely.

However, North Dakota is not a very heavily populated state, thus making Texas the clear leader in the coal rolling game. According to EPA experts, nearly 65,000 tampered trucks have been flagged in Texas alone, with undetected estimates hinting at there being more than double these figures. For years, trucks with emissions defeating software and smoke-stack-style straight pipes have flown under the radar, or in many cases, flaunted their flatulence in plain sight.  

It’s not like regulators are doing much about this issue either. Even bone stock, unmolested diesel vehicles are quick to run dirty on the open road, as opposed to when they are undergoing stringent lab tests. That said, most US government regulators won’t even test vehicle emissions under real-world conditions unless there is a glaring issue, like the Volkswagen shit-storm for instance. Which leads us to our next topic of concern, which is the fact that coal rolling truck enthusiasts aren’t the only ones taking taking a dump on the collective air we breathe.

Photo Credit: World Health Organization

Lethal Diesel: Way More Than Just Rolling Coal

The World Health Organization estimates that a staggering 4.2 million people die every year from exposure to ambient (outdoor) air pollution. While those numbers sink into that statistic saturated skull of yours, here’s another little nugget of info for you to mull over. More than 91% of the world’s population lives in areas where poor air quality exceeds WHO guideline limits, and as overpopulation issues loom, these numbers grow exponentially with each passing year. 

“Almost half of all deaths by air pollution from transportation are caused by diesel emissions, and one in three are linked to emissions from off-road vehicles and international shipping.”

-Climate & Clean Air Coalition (CCAC)

Now here’s the real kicker. A separate study conducted by the Climate & Clean Air Coalition (CCAC) in 2019, discovered that out of all of the air pollution related deaths recorded in 2015, over 385,000 of them were caused by diesel exhaust. Convert that to average years of life lost, and you suddenly have 7.8 million years of human life down the tube, and a whopping $1 trillion dollar hospital bill.

It’s not just dudes in jacked-up turbo-diesel trucks with filthy engines that are poisoning our air either, even though their unfiltered exhaust fumes are far more lethal than emissions regulated smoke. From the trains and trucks that deliver products and people around the globe every hour, to the mining machines and construction equipment at the job site across the street, diesel smoke can be found churning out of exhaust pipes everywhere you turn. 

Photo Credit: TheRailzone /YouTube

As for lax emissions inspections, estimates show that these oversites caused over 38,000 premature global deaths in 2015 alone. Further studies found that these deaths were not just from any old exhaust soot either, but the direct result of people coming into close, consistent contact with the particulate matter suspended within diesel emissions. That’s not from unfiltered coal rollers either, but basic diesel delivery trucks and city buses, as experts predict that these morbidity numbers have climbed even higher in recent years.

Take a gander at the eleven largest vehicle markets, and you’ve got the United States, the 28 members of the European Union, Australia, Brazil, Canada, China, India, Japan, Mexico, Russia, and South Korea. Combined, these countries account for 80% of the diesel vehicles in the world, with studies showing that within these areas “nearly one-third of on-road heavy-duty diesel vehicle emissions, and over half of on-road light-duty diesel vehicle emissions are in excess of certification limits.”

Broken down to its bare nuts and bolts, it becomes apparent that the concentration of polluting diesel vehicles is far more rampant than previously predicted, and far more life threatening. Young children, women, and the elderly are particularly vulnerable to the dangers of diesel exhaust fumes, says the World Health Organization, which continuously urges for the increased regulation of diesel-powered machinery and transportation. 

Quick Nerd Note: Diesel exhaust is a jet-black blend of gases and particulates, which materialize as a by-product during the diesel fuel combustion process. The smallest of these particles is known as diesel particulate matter (DPM), a savory blend of solid elemental carbon (EC) cores and organic carbon (OC) compounds.

Photo Credit: Boursier.com/Facebook

Dodgy Dirty Diesel Testing and the Future of Emissions Regulations

Think new car inspections are strict? Think again. Federal emissions testing in the United States for light-duty vehicles like passenger cars and smaller trucks is little more than a 31-minute dyno lab test. This test consists of a basic tailpipe emissions readings from a cold start, while the vehicle is idling and under throttle, and during a hot start. However, auto manufacturers know this drill better than anyone, and are masters at acing the test.

Reports of specially trained, “hyper-mile” drivers showing-up on the day of the test to help guarantee that automakers get maximum efficiency numbers and lower emissions are quite commonplace. In response, many experts find the entire process laughable. While passing an EPA lab test may yield results, it does not guarantee that an automobile will not exceed these parameters on the open road, especially with a heavy load in the bed, and a driver with an even heavier heel behind the wheel. 

As for vehicles with emissions cheating mods on board, Ars Technica discovered that the EPA’s inspections have been “limited to class 2b and class 3 diesel pickups.” So smaller vehicles and pickups slide right under the radar, as only trucks with gross vehicle weights between 8,501 to 14,000lbs (3,856 to 6.350kg) continue to be targeted. Oh, and when it comes to flagging these larger trucks, the EPA says it will only label a vehicle as “illegally tampered” if its emissions controls have been disabled or removed entirely.

Photo Credit: The Statesman/Facebook

So what does the future of emissions regulations look like? That depends on where you live. While EU regulators have been busy shifting toward requiring diesel vehicles to meet compliance levels during real-world driving tests, Japan has vowed to cut greenhouse gas emissions to net zero by 2050. Meanwhile, back in America, California continues its campaign for stricter emissions standards, and looks toward alternative fuel options. In contrast, many states in America do not plan on regulating or even inspecting diesel vehicles, claiming that it would be troublesome, expensive, and detrimental to local economies.

Contrasting viewpoints illuminated, it becomes clear that when it comes to regulating diesel, there is no clear path forward. These engines have become such a crucial cog in the ever spinning human transportation, manufacturing, and shipping wheel, that it is virtually impossible to regulate their usage and modification. And while cracking down on modified, polluting pickups may help a bit, that is but a single soot-rich smudge on an already oversaturated environment.

In a nutshell, the complete elimination of diesel-powered machines will likely never happen. Hell, the implementation of emissions standards in many parts of America and the rest of the world doesn’t look very certain either, thus making the path forward even more unclear.

However, one thing is for certain, and that’s diesel fuel’s ability to cause severe health issues and even death. Which is precisely why finding ways of producing cleaner version of this fuel source must be pursued. Why you ask? Maybe its a strange desire to breath fresh air. Or perhaps it’s me not being willing to give up on the idea of someday owning a 1948 COE Hauler with a big-ass diesel engine stuffed underneath. Either way, a solution for dirty diesel must be found, and soon…

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