Fiberglass is a synthetic mineral fiber, often called glass wool, commonly utilized in insulation, roofing, and composite materials. It is manufactured by melting tiny glass particles and spinning them into fine fibers. When fiberglass materials are disturbed, such as during installation, cutting, or demolition, these microscopic fibers can become airborne. The primary health concern related to fiberglass is the mechanical irritation caused by these fibers upon contact with the skin, eyes, or the respiratory tract.
How Fiberglass Fibers Affect Lung Tissue
The physical dimensions of the fiberglass fibers dictate where they settle within the respiratory system. Larger fibers are trapped in the upper airways, where they are eventually cleared by natural defenses like coughing or sneezing. However, smaller, respirable fibers can bypass these defenses and travel deeper into the lungs, reaching the bronchioles and the small air sacs known as alveoli.
Once in the deep lung tissue, the fibers cause mechanical irritation. This foreign material triggers an inflammatory response as the immune system attempts to clear the particles. Alveolar macrophages, the resident immune cells of the lungs, try to engulf the fibers, which can lead to inflammation known as acute alveolitis. Unlike certain other mineral fibers, modern fiberglass is biosoluble, meaning it dissolves relatively quickly in the body’s fluids, which aids in its clearance from the lungs.
Acute Symptoms of Respiratory Exposure
Inhaling fiberglass dust results in immediate, short-term, irritative symptoms. Exposure to airborne fibers can cause soreness and irritation in the nose and throat due to the physical scraping of the fibers against the mucous membranes. This irritation is often accompanied by sneezing, a dry, nonproductive cough, and rhinitis.
Some individuals may experience chest tightness or shortness of breath, particularly those with pre-existing conditions like asthma or bronchitis. These symptoms are classified as irritative and are a direct response to the mechanical presence of the fibers. These acute respiratory effects, including eye and skin irritation, subside shortly after the individual is removed from the contaminated environment and the exposure ends.
Assessing Long-Term Health Concerns
A primary concern for many people is whether fiberglass inhalation leads to long-term, permanent lung damage or cancer. Extensive scientific investigation into the long-term health of workers exposed to fiberglass in manufacturing settings has provided valuable data. Studies have shown no consistent evidence of an increased risk of respiratory system cancer or non-malignant pulmonary disease in workers exposed to biosoluble glass wool fibers.
The International Agency for Research on Cancer (IARC) classifies glass wool fibers, the type used in common insulation, as Group 3: “not classifiable as to its carcinogenicity to humans.” This classification is based on inadequate evidence of carcinogenicity in humans and limited evidence in animal studies, especially when compared to highly durable fibers like asbestos. The risk of chronic inflammation or fibrotic changes (scarring) is primarily linked to high, prolonged exposures to certain specialized, highly durable fibers. Modern fiberglass insulation is designed to be less persistent in the lungs, with the fibers breaking and dissolving more rapidly in body fluids.
Immediate Actions and Protective Measures
If you have been exposed to airborne fiberglass, the immediate actions you take can minimize discomfort. Move immediately to an area with fresh air to stop further inhalation of fibers. If clothing is contaminated, it should be removed and washed separately from other laundry to avoid cross-contamination.
Rinsing the mouth and nose with water can help remove fibers trapped in the upper respiratory tract. To prevent exposure when working with the material, proper ventilation, such as opening windows or using a fan to exhaust air, should be established. Protective measures include wearing an N95 filtering facepiece respirator to minimize fiber inhalation, along with long-sleeved clothing, gloves, and eye protection.