Colorectal Cancer Risk Factors, Occupational Exposures, and Screenings

Lawrence Buirse

Providing preventive health screenings for a workforce can offer short- and long-term benefits. First and foremost, because these are preventive screenings, the obvious goal is to check for early red flags of serious illnesses so that they don’t develop into chronic or debilitating conditions. These screenings also positively impact employees’ fitness for work by helping them avoid serious health conditions that could force them to either miss work regularly or perform only at a limited level. Additionally, providing preventive health screenings for employees promotes employee wellness, which can help foster a positive workforce culture and score a big win for employee morale.

From a business perspective, on top of helping to ensure employees are both fit and available for work, providing preventive health screenings can help control employee health care costs. Routine screenings can aid in identifying health issues that could place an employee at higher risk of suffering a costly work-related injury or illness.1

Workforce health screenings are often connected to a corporate wellness strategy. One of the most common workplace wellness screenings is a biometric screening, which can be critical in identifying serious health risks for employees. This screening measures vital health statistics such as blood pressure, blood glucose, cholesterol, and body mass index (BMI). But there are other preventive health screenings that are equally important in identifying serious health conditions and/or their associated risk factors. For example, workplace cancer screenings are becoming more commonplace — and for good reason. Recent data reveals that at least 42 percent of newly diagnosed cancer cases in the U.S. are potentially preventable.2

Some professions such as firefighting and asbestos abatement can increase employees’ risk of exposure to cancer-causing agents. Employers should take proactive steps to (a) determine which health conditions may be prevalent based on their given work environments and (b) conduct preventive screenings for early detection of these conditions to reduce the likelihood of costly, debilitating work-related injuries and illnesses emerging over time.

Workplace screenings for colorectal cancer

One of the costliest health conditions that can develop (and be associated with certain occupational exposures) is colorectal cancer (CRC), which is also one of the most common cancer types.2

“Colorectal cancer occurs when the cells that line the colon or the rectum become abnormal and grow out of control,” explained Ronda McCarthy, MD, MPH, FACOEM, national medical director of medical surveillance services at Concentra®. “It is any cancer that affects the colon or rectum.”

Colorectal cancer is the second most expensive type of cancer to treat in the U.S. — sharing this unfortunate distinction with lung cancer — while breast cancer tops the list.3 Colorectal cancer is also the second most common cause of cancer-related deaths in the U.S.3

The longstanding belief around CRC was that it primarily affected the older population; however, recent data tell a different story, which has resulted in the lowering of the age at which CRC screening is recommended to begin.4

“Because CRC incidence rates are increasing in younger populations, the age to initiate CRC screening has been lowered from 50 to 45 years,” said McCarthy.

Dr. McCarthy further explained that modeling studies demonstrated how the balance of benefit to harm was more favorable for beginning screening at age 45 than at 50.

“Although health insurance coverage for screening those at average risk before age 50 remains variable, the American Cancer Society is working aggressively to educate insurers, lawmakers, and other stakeholders about the evidence in support of screening those age 45 to 49 years and the importance of expanding coverage for this group,” McCarthy said.

Colorectal cancer symptoms

Like some serious health conditions, early symptoms of CRC are not always easily detectable — a point that only reinforces the importance of preventive screenings. Some of the most common symptoms include4:

  • Blood in the stool following a bowel movement
  • Dark stools
  • Chronic constipation or diarrhea that lasts for days
  • Constant discomfort in lower abdomen
  • Bleeding from the rectum

Many symptoms can be the result of related conditions and not of CRC itself, such as irritable bowel syndrome or hemorrhoids.

Common risk factors of colorectal cancer

There are certain lifestyle and hereditary factors that can increase an employee’s risk of developing CRC, including:

  • Age (i.e., age 50 and older)
  • Family history of colorectal cancer
  • Personal history of inflammatory bowel disorders (e.g., ulcerative colitis or Crohn’s disease)

Lifestyle factors that can increase a person’s risk include5:

  • Unhealthy weight/obesity
  • Sedentary lifestyle/physical inactivity
  • Poor diet/nutritional deficiencies

Despite the commonality of several risk factors associated with CRC, many people who may be at risk have never been screened because they may be asymptomatic and/or share preconceived notions about their risk of developing the condition.

Occupational exposures and risks for colorectal cancer

While colorectal cancer is not considered a cancer that is primarily caused by workplace exposure to cancer-causing agents, there is existing data that reveals how some industries can heighten employees’ risk of developing this form of cancer.6

CRC preventive screenings are recommended for firefighters or employees who work in environments that expose them to carcinogens such as certain solvents, dyes, dust, and other contaminants. That also includes employees exposed to asbestos and chemicals in manufacturing.

Colorectal cancer employee screening options

Generally, there are two types of CRC screenings: visual/structural exams and stool-based tests.7 Visual/structural exams are typically invasive screenings. The most common visual/structural exam is the colonoscopy. This procedure uses a colonoscope, or tube-like instrument with a light and tiny video lens attached, that is inserted into a patient’s rectum and colon to look for cancer, polyps, or any abnormalities.7

Although a colonoscopy is invasive, most patients are sedated during the relatively brief, outpatient procedure. Some prep work is required, such as the consumption of bowel prep medication and adherence to certain dietary restrictions (e.g., clear liquid diet) within a designated period before the procedure. Based on the findings, results can be available shortly after completion of the procedure. If a physician spots a polyp or removes a sample of the colon for further testing, it may take a few days to provide a patient with results.

Stool-based tests involve the use of a test kit for collecting a patient’s stool sample. One of the most utilized stool-based tests is the Fecal Immunochemical Test (FIT). This non-invasive screening is used to detect hidden blood in the stool; this presence of blood cannot be seen by the naked eye. Blood in the stool may be caused by colorectal conditions such as polyps, hemorrhoids, colitis, diverticulitis, or fissures. These conditions may leak small amounts of blood into the lower intestine.

Stool-based tests include instructions on how to collect and submit stool samples for testing. No prep work or dietary restrictions are required for completion; however, if blood is detected in a stool sample, additional testing — such as a colonoscopy — might be necessary to thoroughly rule out the possibility of cancer.

According to Dr. McCarthy, American Cancer Society and U.S. Preventive Services Task Force guidelines do not emphasize any one CRC screening type and stress that all recommended screenings can help save lives.

“The best CRC screening is the one the patient will perform,” said McCarthy. “A recent national survey shows that if offered the choice, take-home, stool-based screening is preferred over the office and hospital-based colonoscopy for CRC screening.”

Current research also suggests that, regardless of screening type, simply undergoing a CRC preventive screening can reduce an individual’s risk of developing this form of cancer.8 For example, if polyps are discovered during a colonoscopy, they could be benign; however, some may be precancerous growths that could turn cancerous over time if not detected early and removed. Even if a CRC screening results in a cancer diagnosis, detecting signs of cancer in the earliest possible stages offers the best chance for a full recovery.

Concentra provides workforces with at-home CRC screening resources

Concentra makes it possible for employees to complete a CRC screening from the privacy and comfort of their home. Concentra offers Hemoccult™ ICT (Immunochemical Test) 2-Day FIT screenings to employees in industries where occupational exposure to carcinogens is higher than average. Concentra also recommends integrating the CRC screening resource into a company’s wellness program.

Hemoccult ICT 2-Day FIT is a take-home test that can be used for wellness exams, asbestos exams, firefighter physicals, and other preventive health employee screenings. Here’s how it works:

  1. Employee receives FIT testing kit from Concentra to take home.
  2. Employee collects two different stool samples — one per day (hence, the name “2-Day”) — records collection dates, and returns kit (with stool samples) to Concentra.
  3. Concentra processes the samples.
  4. Test results are recorded in the employee’s medical chart, and results are reported confidentially to the employee.

Employers can authorize employees to pick up a Hemoccult ICT 2-Day FIT patient screening kit at any Concentra medical center. For more information about CRC screenings, please visit our website or contact your nearby Concentra medical center.


  1. Centers for Disease Control and Prevention. (2022, June 9). Chronic Disease Fact Sheet: Workplace Health Promotion. National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).
  2. Cancer Facts and Figures 2022. American Cancer Society. (n.d.).
  3. Centers for Disease Control and Prevention. (2020, December 2). Colorectal Cancer.
  4. Colorectal Cancer Facts and Figures 2020-2022. American Cancer Society. (n.d.).
  5. Centers for Disease Control and Prevention. (2022, February 17). What are the risk factors for colorectal cancer?
  6. Duijster, J., Mughini-Gras, L., Neefjes, J., and Franz, E. (2021, August 1). Occupational exposure and risk of colon cancer: A nationwide registry study with emphasis on occupational exposure to zoonotic gastrointestinal pathogens. BMJ Open.
  7. Colorectal Cancer Screening Tests: Sigmoidoscopy and Colonoscopy. American Cancer Society. (n.d.).
  8. Bretthauer, M., Magnus, L., Wieszczy, P., Kalager, M., Emilsson, L., Garborg, K., Rupinski, M., Dekker, E., Spaander, M., Bugajski, M., Holme, Ø., Zauber, A., et al., for the NordICC Study Group. (2022, October 27). Effect of colonoscopy screening on risks of colorectal cancer and related death. New England Journal of Medicine.