Managing the Hidden Risk of Work-related Asthma


In this webinar, you will learn about:

  • Occupational asthma and links to work clearly defined
  • Different forms of occupational asthma that can affect employees
  • Which industries and job roles are most impacted by asthma
  • Views of two medical doctors on asthma testing, treatment, and prevention


Presented by: Ronda McCarthy, MD, MPH, FACOEM National Director of Medical Surveillance Services

Deepa Rajakrishnan, MD, MBA Director of Medical Operations



Hello and welcome to the Concentra® webinar, Managing the Hidden Risk of Work-related Asthma. Today’s webinar will be presented by Dr. Ronda McCarthy and Dr. Deepa Rajakrishnan. Dr. McCarthy is Concentra’s national medical director of medical surveillance services and an internationally recognized expert in occupational medicine. Dr. Deepa is the director of medical operations in north Texas, overseeing more than 30 clinicians to ensure quality care at Concentra medical centers. At the conclusion of the presentation, we will have a 10-to-15 minute Q and A session with Dr. McCarthy and Dr. Deepa. You can submit your questions throughout the presentation to be answered during the Q and A. They will answer as many questions as possible within the time allowed. A recording of the webinar will be e-mailed to you after the presentation, as well as a copy of the slides, so you can view it again at your convenience.

Dr. McCarthy, Dr. Deepa, we're ready to begin.

Agenda and What is Asthma?


Thank you for joining us today. In this webinar, we will be discussing the definition of occupational asthma and how much impact it has on the workforce and the community in general. We will also walk through the steps on how to screen for occupational asthma and see what you, as an employer, can specifically do. We will also talk about how increased awareness is essential so that occupational asthma is identified early to help reduce the burden on the employee.

Let’s look at a few points to orient everyone to what asthma is. Asthma is a respiratory condition marked by inflammation in the bronchi. This inflammation causes difficulty in breathing. The usual process of this inflammation is either an allergic reaction to a substance or lung tissue developing increased sensitivity to the offending substance. Asthma is very different from other respiratory diseases, such as chronic obstructive pulmonary disease, because occupational asthma is an airway dysfunction that is reversible with proper management.

The Impact of Occupational Asthma


Diving into occupational asthma – when asthma is caused by specific irritants in the workplace, it is referred to as occupational asthma. Similar to the guidelines for managing asthma, occupational asthma is also a reversible condition. This means, when the substances that caused the asthma are avoided, symptoms may disappear.

It is estimated that there are more than 300 substances in the workplace that may either cause asthma or cause worsening of pre-existing asthma symptoms. We have to remember, even though the list you see covers many agents that can cause or worsen asthma, this list is not complete. New materials and new processes introduce new exposures and create new risks every day. They continue to be added.

The Occupational Safety and Health Administration (OSHA) says that every year about 11 million employees are exposed to one or more of these agents, thereby increasing the incidence of occupational asthma. Some examples of these substances are plant-based soluble fiber, animals and animal byproducts, formaldehyde, latex, isocyanates, wood dust, welding fumes, chromium, and other chemical compounds, including cleaning supplies.

Here are some interesting facts about the impact of occupational asthma and why it is important to recognize it and take action to prevent it.

Number one, over about 17 years, from 1999 to 2015, about 33,370 adults died of asthma, and it is estimated that about 21 percent of these deaths were attributed to work-related exposure and, hence, were potentially preventable.

Number two, occupational asthma is estimated to result in 8.7 million lost workdays each year.

Number three, adults with asthma go to the emergency department for treatment two times more often than adults who do not have asthma. They also are hospitalized 4.6 times more.

Work-related asthma can be further divided into two categories based on occurrence. Number one, does the work exacerbate the asthma? These are employees with pre-existing asthma who experience a burst of asthma symptoms at work. The second type is new-onset occupational asthma, where asthma is caused by exposures in the workplace.

The National Institute for Occupational Safety and Health (NIOSH) states that occupational asthma can show up shortly after exposure or it can develop months or years after repeated exposure to harmful substances. Let us look at some examples of both the categories.

First is an example of work-exacerbated asthma. This was a 39-year-old man who had asthma prior to starting work with an automobile manufacturer. Even though he had asthma when he started the job, he did not have any symptoms. He was a smoker, and he was obese but nothing of concern came up during the annual checkup. His work involved die design, machining, grinding, injection process simulation, and inspection. Six years after he started his job, he developed a cough and difficulty breathing. A year later, breathing difficulties sent him to the emergency department. A year later, he died at age 47. The cause of death was work-exacerbated asthma due to exposure to styrene, a chemical that was used in the injection process.

Next is an example of new-onset occupational asthma. A laboratory that was handling animals hired students to work as lab technicians at the facility. The median age of the students was 21. There was a total of 38 students. After an average of 18 months working with laboratory animals, they were re-evaluated. Nine students (24%) had developed allergies to laboratory animals. Symptoms exhibited included nasal and eye irritation, skin rashes, and chest problems. Of the nine students with animal allergies, seven had reactions to rat or mouse antigen, and eight showed asthma-like reactions during lung testing.

Given the 300-plus substances that are associated with occupational asthma, the prevalence is across several industries. For example, construction, food processing and production, transportation, oil and gas extraction, health care, textiles, cosmetics, and pharmaceuticals.

Occupational asthma can be avoided with awareness and vigilance. NOSH states, “Worsening asthma or new-onset asthma in an employee should raise concerns about workplace causes. Protecting employee health is certainly a compelling reason to mitigate occupational asthma. This involves effective employer controls and medical screening.

Next, Dr. McCarthy is going to talk about how these critical measures go a long way to help avoid development of occupational asthma. Doctor McCarthy?

Screening for Occupational Asthma


Thank you, Dr. Deepa. As Dr. Deepa related earlier, occupational asthma is a disorder of the airways that involves a complex interaction of airflow obstruction, bronchial hyperresponsiveness, and underlying inflammation with increased airway responsiveness. This can result from an allergic hypersensitivity or irritant response to a substance after a one-time event or years of exposure to the substance.

Let's look at why medical screening employees for signs, symptoms, and sensitivity to workplace asthma agents, or substances that can cause the development of asthma, is important to prevent unnecessary illness and associated cost.

Asthma symptoms consist of one or many of the following: cough, difficulty breathing, shortness of breath, wheezing, and chest tightness. Symptoms may also be associated with nasal congestion, watery eyes, and skin rash, as Dr. Deepa alluded to earlier. Early symptoms of asthma may start with clearing of the throat and slight chest tightness that may be ignored by the employee until the symptoms become more severe.

This is where medical screening of employees exposed to known antigens or sensitizers can play an important role in identifying the employee with early health effects of asthma.

Ways to confirm and document the health effects include immune and lung function testing. For some workplace substances, such as formaldehyde, chromium, and diacetyl, OSHA requires a medical surveillance examination. Laboratory animal exposure can require medical surveillance of exposed employees in order for laboratories to meet certification standards. Other employers find that post-offer examinations and periodic medical evaluations help decrease the direct and indirect costs associated with work-related asthma and allergy illness, while optimizing employee health.

Let's walk through a typical medical evaluation for a substance known to be highly sensitizing, like isocyanate. Isocyanate comes in a few forms and is a chemical used in construction and manufacturing. Ideally, employees medically evaluated for baseline and ongoing periodic health surveillance exams will have a complete health history and occupational history, including their asthma and allergy symptomatology. The clinicians should thoroughly evaluate asthma and allergy symptoms, past and present.

The physical exam will focus on the health effects specific to the chemical exposure. Specifically for asthma and allergy, we have the evaluation of the upper and lower respiratory system, the cardiovascular system to ensure there are no other complicating factors, and the skin exam. Testing common to isocyanate evaluation and other sensitizing substances include baseline spirometry, or lung function testing, and the chest X-ray.

Subsequent periodic examination should include all that we just discussed in the evaluations and to monitor their respiratory health over time – except the chest X-ray is ordered only as indicated.

If the evaluation indicates that an employee has become sensitized or developed signs and symptoms of asthma, additional testing can be ordered. The evaluating health care provider will review all prior records. Bronchodilator reversibility testing can be ordered. This is a test to document asthma or reversible airway disease. An employee cannot be diagnosed with occupational asthma if they do not indeed have asthma. Once the bronchodilator reversibility test is performed, and it’s shown to be positive, peak flow testing can then be ordered to look for an occupational trigger at the workplace.

The information gained from the medical surveillance, including the medical evaluation and the lung function testing, may lead to early detection of health effects.

Detecting health effects early allows for earlier management and adjustment of employer controls. Reassignment away from the exposure – specifically isocyanate in this example – or other measures are crucial, as isocyanate specifically is associated with severe occupational asthma, and that may lead to death even when the exposure is lower than OSHA’s permissible exposure limit.

Options for Employer Response


So what can employers do when working with potentially hazardous substances? Here we show an example of NIOSH’s hierarchy of controls, which continues to be one of the best protocols to guide employers on how to decrease or eliminate the harmful health effects associated with hazardous exposures. The first option is to eliminate the hazard or substitute a less hazardous one. Next is installing engineering and applying administrative controls to reduce or restrict your exposure. The last on the hierarchy is personal protective equipment – usually respirators in this instance, and they are best when used correctly and worn correctly. Employees can also offer medical surveillance and screening to employees to complete to complement the hierarchy of controls.

Medical surveillance programs monitor an employee or a similarly exposed group of employees over time. This provides feedback to the employer on their engineering and other worksite controls. It evaluates employees for fitness for duty in the work environment, working with specific hazards, and screens employees over time for potential health effects related to the potentially hazardous exposure so early intervention can occur.

Awareness and Communications


Occupational or work-related asthma is an underrecognized risk. Increased awareness and communication can help prevent disease, disability, and death. Current research reports that many employees, employers, and health care professionals lack awareness and underreport work-related asthma. This decrease in awareness contributes to delayed diagnosis and poor outcomes.

Basically, there needs to be better communication about asthma, in general, among employees and healthcare providers. Is important for all health care providers to ask questions regarding home and work exposures when patients present with signs and symptoms of asthma, most importantly, when these symptoms are new and mild.

Unfortunately, employees may feel early or mild symptoms do not warrant seeking medical attention.

They may not associate their symptoms with work but, instead, think it’s age-related, a need for physical conditioning, or related to seasonal allergy symptoms. There may be time pressures or fears that may interfere with reporting their symptoms until the conditions become unbearable. This is where periodic medical screening is crucial to detect early and potentially reversible disease when exposed to occupational antigens.

There are direct and indirect costs of misdiagnosis. Indirect costs include decreased worker productivity when asthma is uncontrolled, lost workdays, workers' compensation expense, and disability costs. The direct costs include treating the illness, medications, office visits, emergency department visits, and hospitalizations, as Dr. Deepa mentioned earlier, and the unmeasurable cost of occupational asthma resulting in death.

To address these costs and, most importantly, the health of employees, Concentra has taken steps to ensure the consistency and the visibility of our occupational allergy and asthma services nationwide. We have added new tests, allergy and asthma medical evaluations, and clinician training to ensure optimal diagnostic services and care.

We're also raising awareness through communication – such as this webinar – information materials, and articles. An example is an article, shown on the left, which was published last month in Construction Executive.

So, thank you for your attention on this important topic for the health and safety of your employees. Now I'll pass it back to the moderator for any questions you may have. Thank you.