P1241B

SECTION 2: Hazards identification

EMERGENCY OVERVIEW This product is a mixture of polymeric isocyanate and monomeric isocyanates. The health effects of polymeric isocyanates have not been fully investigated. Isocyanates in general are irritating to eyes, skin, and respiratory system. Exposure to moderate levels of isocyanates can result in respiratory or skin sensitization, especially in predisposed persons such as those with respiratory problems, recurrent skin eczema, or skin allergies. Polymeric isocyanates normally have low volatility, but heating, spraying, or other processing, especially in poorly ventilated areas, can increase exposure risk. Sensitized persons should not be exposed to any material containing unreacted isocyanates.

Principle Routes of Exposure

Inhalation, Skin contact, Ingestion Acute exposure Inhalation : Isocyanates vapor or mist at concentrations above the TLV can irritate the mucous membranes in the respiratory tract (nose, throat, lungs) causing runny nose, sore throat, coughing, chest discomfort, shortness of breath, and reduced lung function (breathing obstruction). Persons with a pre-existing, non-specific bronchial hyper-reactivity can respond to concentrations below the TLV with similar symptoms as well as asthma attacks. Exposure well above the TLV may lead to bronchitis, bronchial spasm and pulmonary edema (fluid in the lungs). These symptoms can be delayed up to several hours after exposure. As a result of previous repeated overexposures or a single large dose, certain individuals develop isocyanate sensitization (chemical asthma) which will cause them to react to a later exposure at levels well below the TLV. These symptoms, which can include chest tightness, wheezing, cough, shortness of breath, or asthma attack, could be immediate or delayed (up to several hours after exposure). Similar to many non-specific asthmatic

Response

there are reports that once sensitized an individual can experience these symptoms upon exposure to dust, cold air, or other irritants. This increased lung sensitivity can persist for weeks or in severe cases for several years. Overexposure to isocyanates has also been reported to cause lung damage (including decreased lung function), which may be permanent. Sensitization can either be temporary or permanent. Ingestion : May be harmful if swallowed. Can result in irritation and corrosive action in the mouth, stomach tissue, and digestive tract. Symptoms can include sore throat, abdominal pain, nausea, vomiting, and diarrhea. Eyes : Liquid, aerosol, or vapors of this product are irritating and may cause tearing, reddening, and swelling accompanied by a stinging sensation and/or a feeling like that of fine dust in the eyes. If left untreated, corneal damage can occur, and injury is slow to heal. However, damage may be reversible with time. Skin : Isocyanates react with skin protein and moisture in the skin and can cause irritation which may include reddening, swelling, rash, scaling or blistering. Cured material is difficult to remove. Prolonged contact may cause skin sensitization in some cases. Individuals who have skin sensitization can develop these symptoms from contact with liquid or vapors. Animal tests have indicated that respiratory sensitization can result from direct skin contact with isocyanates. This data reinforces the need to prevent direct skin contact with isocyanates. Chronic exposure : Refer to Section 11 for Toxicological Information.

Medical Conditions Generally Aggravated by Exposure

Individuals with chronic respiratory disorders (i.e. asthma, chronic bronchitis, etc.) may be adversely affected by any airborne contaminant.