Ethylene Oxide/Carbon Dioxide Mixture Mixture

SECTION 2: Hazards identification

Emergency Overview DANGER! Cancer hazard and reproductive hazard. Toxic, extremely flammable liquid and gas under pressure. Can form explosive mixtures with air. Can cause eye and skin burns. Can irritate the respiratory tract. May cause nervous system damage and cataracts. Liquid may cause frostbite. May cause dizziness and drowsiness. Symptoms of exposure may be delayed. Self-contained breathing apparatus must be worn by rescue workers. Ethylene oxide is highly reactive.

Principle Routes of Exposure

Absorbed through skin. Eye contact. Inhalation. Ingestion. EFFECTS OF A SINGLE (ACUTE) OVEREXPOSURE: INHALATION: Asphyxiant. Moderate concentrations may cause headaches, drowsiness, dizziness, stinging of the nose and throat, excitation, rapid breathing, excess salivation, vomiting, and unconsciousness. Lack of oxygen can kill. Causes irritation of the respiratory tract. Carbon Dioxide is also a physiological active, affecting circulation and breathing. Depending on the degree of exposure, there may be coughing, chest tightness, nausea, diarrhea, weakness, cyanosis, loss of coordination, convulsions and coma. May cause lung injury and the delayed onset of pulmonary edema. SKIN CONTACT: With liquid or solutions in water, there may occur a local erythema, edema, and formation of vesicles. There may be a latent period of several hours prior to the onset of these signs. Liquid may cause frostbite. SKIN Sustained contact with the skin is unlikely, but can cause headache, dizziness, nausea and ABSORPTION: vomiting. A dilute solution may penetrate skin, producing, a chemical burn. SWALLOWING: A highly unlikely route of exposure. Will cause severe irritation and ulceration of the mouth and throat, abdominal pain, nausea, vomiting, collapse and coma. Frostbite of the lips and mouth may result from contact with the liquid. EYE CONTACT: Liquid may cause frostbite and severe irritation with corneal injury. Moderate irritation from high concentrations of vapour. EFFECTS OF REPEATED (CHRONIC) OVEREXPOSURE: Ethylene Oxide: Allergic contact dermatitis may occur in a small proportion of exposed workers. In various reports involving recurrent exposures to high concentrations of ethylene oxide vapour, peripheral neurotoxic effects, and, in some cases, indications of central nervous system toxicity, where described resulting from gross overexposure. In most cases, there was marked improvement on removal from further exposure. A few cases of cataract formation have increased incidence of abortions, the laboratory findings indicated that if adverse reproductive effects are produced by ethylene oxide, these occur only at high exposure concentrations. Several studies on ethylene oxide exposed workers have demonstrated an increased incidence of chromosomal aberrations and sister chromatic exchanges; the relevance of such effects to human health hazards evaluation is currently uncertain. OSHA considers that, at excess levels, Ethylene Oxide may present reproductive, mutagenic, genotoxic, neurologic and sensitization hazards. Carbon Dioxide: No harm expected. OTHER EFFECTS OF OVEREXPOSURE: Ethylene Oxide: May cause cataracts. Carbon Dioxide: Damage to retinal ganglion cells and central nervous system may occur.

Medical Conditions Generally Aggravated by Exposure

OVEREXPOSURE The toxicology and the physical and chemical properties of this product suggest that overexposure is unlikely to aggravate medical condition. SIGNIFICANT LABORATORY DATA WITH POSSIBLE RELEVANCE TO HUMAN HEALTH HAZARD EVALUATION: Ethylene Oxide: This component has been shown to produce mutagenic and cytogenic effects in a variety of test systems. Animals exposed to ethylene oxide vapour for up to two years have shown an increase in the incidence of certain malignant tumors in comparison to nonexposed controls. In humans, an increased occurrence of leukemia and stomach cancer has been reported by one group of investigators who pooled results from three Swedish facilities producing or using ethylene oxide, among other materials. Based on experimental and observational data ethylene oxide is a suspect cancer hazard, and should be treated as possible causing cancer in humans. Laboratory studies with mice have shown that acute exposure to ethylene oxide vapour at concentrations of 30 ppm and above cause testicular injury as evidenced by concentrations-related increased embryonic deaths following the mating of exposed males to nonexposed females (Dominant Lethal Test). A recently completed NIOSH study of sterilant workers found an elevated risk of blood cancers among men and breast cancers among women. The elevated risk occurred only at high exposures as defined by a combination of exposure level and years worked. The study showed no elevated cancer or disease risk for sterliant workers overall as compared to the general U.S. population. In a developmental toxicity study with rats exposed to 225, 125, or 50 ppm of ethylene oxide vapor, there was maternal toxicity at 225 ppm and at 125 ppm. Fetotoxicity was present as reduced fetal body weight at all concentrations, and increased incidents of skeletal variants at 225 ppm indications of embryotoxicity or malformations. In a two-generation oxide vapor for 6 hr/day, 5 day/week, there was parental toxicity at 33 and 100 ppm. Postimplant losses with reduction in litter size and offspring bodyweight were present at 33 and 100 ppm. The no-observed-effects concentrations for adult toxicity, offspring effects, and reproductive effects was 10 ppm. Carbon Dioxide: A single study has shown an increase in heart defects in rats exposed to 6% carbon dioxide in air for 24 hours at different times during gestation. There is no evidence that carbon dioxide is tetratogenic in humans. CARCINOGENICITY: Ethylene Oxide: OSHA considers ethylene oxide to pose a human cancer hazard and a human reproductive hazard. The IARC assigns it to Group 1, "Carcinogenic to humans". The NTP classifies it as "Known to be a human carcinogen".