What Causes Lung Cancer?

One of the most frequently asked questions for lung cancer patients that have many answers. When tumors develop in the lungs, it’s known as lung cancer and there are several causes. These causes include exposure to cancer-causing compounds known as carcinogens. Each day, there are a number of carcinogens that you or a loved one may be exposed to at work, school, or in your home (without your knowledge). These carcinogens can include dangerous gases, such as radon, or even building materials that used hazardous chemicals or products, like asbestos. Once exposed for a long period, the prevention of lung cancer could prove difficult.

Hazardous Chemicals

Several chemicals can be dangerous when humans are exposed to them regularly. Much of these chemicals can be found on job sites and in old or poorly maintained building structures, including residences. It’s the responsibility of the owner or manager of the contaminated structure to have the pollutant adequately removed before anyone enters the premises and gets exposed unknowingly.

The Environmental Protection Agency (EPA) is the government agency in charge of enforcing the hazardous exposure and environmental quality regulations, though companies have slipped through the cracks and defied laws, previously. If you or a person you know was exposed to a harmful substance while on the job, it could be due to corporate negligence, and you may be entitled to a settlement or compensation. Hazardous chemicals and other products can include:

This is an icon displaying what asbestos looks like in a home.


Once known for its durability, fire-resistance, and cost-effectiveness, asbestos was once referred to as a “miracle mineral” (pre-1982) and used in many different construction capacities. Primarily, it was used as insulation for pipes, boilers, automobile brake linings, and more before it was discovered to be carcinogenic.

Asbestos is made up of a bundle of fibers that, when disturbed and crumbled into small particles, can be extremely dangerous. If the fibers are expelled into the air, they can become lodged in a person’s lungs, irritate the tissue over time, and eventually cause the cells to mutate and develop into a type of lung cancer. However, asbestos is also linked to mesothelioma diagnoses, a rare disease that affects the lining of the lungs as well as other parts of the body. Mesothelioma can sometimes be misdiagnosed as lung cancer since it is not as common.

This is an icon representing different types of radon exposure.


The second leading cause of lung cancer is exposure to a poisonous, naturally occurring, radioactive gas called radon. What makes the gas so dangerous is its lack of color and odor. Radon causes approximately 21,000 lung cancer deaths every year. Typically, the gas oozes out of the soil and into the air. Usually, bits of radon float throughout the environment in many places outside. However, it only becomes dangerous in concentrated environments, such as inside houses and other residences.

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Another mineral, uranium ore has been used as an abundant source of concentrated energy for over 60 years. Uranium naturally occurs in rocks and seawater. Generally, it is mined and sent to processing plants to utilize for nuclear energy. The energy this method supplies adds up to about 11 percent of the world’s annual electricity. It is also used to power nuclear plants, reactors, in radioisotopes, and as a source of fuel for the military.

Since this mineral is radioactive, exposure to high concentrations of enriched uranium for extended periods can cause healthy cells to mutate and begin multiplying excessively. This process has been known to cause lung cancer as well as other types of cancer. Fortunately, depleted or naturally occurring uranium has never specifically caused any human cancer.

This is an icon representing different types of arsenic exposure.


A natural element that can be found in soil, rocks, water, air, plants, and animals, arsenic is abundant in the environment. Typically, humans take in low levels of arsenic when we breathe, drink water, and eat food. Though, this exposure is less dangerous. When people breathe in arsenic, it could put them at risk to develop lung cancer.

Before 1985, arsenic was used in several human-made products – primarily pesticides and herbicides. This fact put those who transported, applied, or worked around these toxic products at high risk for exposure to dangerous levels of arsenic. Those spending a lot of time around former agricultural sources of arsenic, older industrial buildings, or coal processing plants are also at high risk of dangerous exposure.

This is an icon representing different types of cadmium exposure.


Classified as a carcinogen in 1993, cadmium is another naturally occurring element that can be found in small amounts in air, water, soil, and food. All soils and rocks, including fertilizers made from coal and minerals, host cadmium. Cadmium’s extracted when producing zinc, lead, and copper. It’s also been used to manufacture batteries, pigments, metal coatings, and plastics.

Those who work in factories where cadmium products are made or those who ingest cadmium products such as secondhand tobacco smoke and cadmium-contaminated foods are more likely to have a dangerous level of exposure to the element. Cadmium exposure has been known to be among the causes of lung cancer as well as prostate, pancreatic, and kidney cancer.

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There are two types of chromium, trivalent chromium (known as Cr III) and hexavalent chromium (known as Cr VI). This element is most toxic in its Cr VI state, primarily targeting the respiratory tract, but Cr III can be an essential element in humans.

Chromium was popular in industrial capacities and is used primarily for making steel or other alloys. It’s also used in the manufacture of dyes, pigments, leather, wood preservation, and chrome plating.

This is an icon representing different types of nickel exposure.


This carcinogenic element can be mined from the earth’s crust. Commonly, it is combined with other elements to form nickel compounds that can have a multitude of industrial uses. Most nickel is used in metal alloys because of its corrosion- and heat-resistance, durability, and strength.

In factories and plants where nickel is produced, toxic exposure to the substance is likely. This includes mining, smelting, welding, casting, and grinding. Nickel can cause lung cancer when its particles are inhaled through fumes or by skin contact.

This is an icon representing different types of petroleum exposure.


It’s in our gasoline and we commonly use it in tires, refrigerators, life jackets, and anesthetics. Petroleum, also known as petrolatum, is crude oil that’s also a fossil fuel. Much like other fossil fuels such as coal, petroleum is made from the remains of ancient marine organisms. These organisms included ocean plants, algae, and bacteria. When plants and animals sank to the seafloor at the end of their lifecycle, their remains (fossils) developed into carbon-rich substances after millions of years of extreme heat and the pressure from being crushed by tons of layers of sediment and plant debris. Today, petroleum is found in massive underground reservoirs where ancient seas once thrived.

Petroleum starts to get dicey when it’s burned for energy and, then, releases high amounts of toxic gases, such as carbon dioxide. Prolonged inhalation or exposure to petroleum products has been associated with lung disease and cancers.

This is an icon representing different types of particle pollution exposure.

Particle Pollution

Another cause of lung cancer is particle pollution or smog. Think dirty truck exhausts and smoke from power plants and chimneys. More specifically, particle pollution occurs when a mix of small, toxic liquid particles end up in the air we breathe. Usually too small to see, prolonged inhalation of the air in toxic environments can shorten your life and even cause lung cancer. First responders like firefighters encounter particle pollution and smog a lot, as they are the first ones on the scene. California is the state with the highest levels of particle pollution in the nation, with Pennsylvania coming in a close second.

What’s Next?

If you’re concerned you’ve been exposed to any of these carcinogens, visit your doctor as soon as possible for early screening and diagnosis. Screenings are imaging and blood tests that doctors administer to detect the presence of lung cancer or other illnesses. The earlier anything is detected, the more treatment options there are.