Isocyanates Profile

Diagnostic information: Exposure to isocyanates may cause chemical bronchitis with initial symptoms of throat irritation, laryngitis, coughing, and chest pain or tightness.¹ Asthma (with symptoms of wheezing, coughing, and shortness of breath) may also follow exposure to isocyanates.¹ Other effects associated with isocyanate exposure are hypersensitive pneumonitis, chronic pulmonary disease, and contact dermatitis (following direct skin contact).¹

Clinical significance: Between 2% and 15% of all asthma associated with industry attributed to occupational exposure to chemicals.² Quantitative allergen-specific IgE testing offers the capability of monitoring workplace exposure to isocyanates through the measurement of acid isocyanate-specific IgE levels. Increases in acid specific IgE levels are correlated with elevations in exposure.¹

Sources of exposure: TDI, MDI, and HDI are three of the most frequently used isocyanates in industry.³ The isocyanates are used primarily as starting materials for a variety of manufacturing processes, including the production of plastics, polyurethane, foams, and electrical wire insulation.¹ Isocyanates are also common components of paints and other durable and protective finishes, adhesives, and elastomers in automobile bumpers, printing rolls, and coated fabrics.¹ Exposure can occur at any stage from the initial manufacturer of the isocyanates to their final use in various production processes.¹ Exposure can also occur from the application of paints and polyurethanes, from the handling and machining of foams, and from the combustion of these materials.¹