1 / 25

Methyl Isocyanate (C 2 H 3 NO)

Methyl Isocyanate (C 2 H 3 NO). Methyl Isocyanate - Overview. Physical properties Colorless liquid with a very distinct, sharp odor Highly flammable with low flash point Extremely toxic to people. Methyl Isocyanate - Overview.

kasi
Download Presentation

Methyl Isocyanate (C 2 H 3 NO)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Methyl Isocyanate (C2H3NO)

  2. Methyl Isocyanate - Overview • Physical properties • Colorless liquid with a very distinct, sharp odor • Highly flammable with low flash point • Extremely toxic to people

  3. Methyl Isocyanate - Overview • A chemical intermediate in production of carbamate insecticides/herbicides • 1984 accidental release in Bhopal, India killed 3-5,000 and injured 170,000

  4. Methyl Isocyanate - Toxicity • Extremely toxic to humans • Inhalation exposure: LD50 < 200 mg/m3 • Oral exposure: LD50 of 50-500 mg/kg • 23 mg/m3 is irritating to the eyes, nose, and throat • 68 mg/m3 results in a risk of severe injuries • 225 mg/m3 may result in death

  5. Methyl Isocyanate - Toxicity • OSHA / NIOSH standards for skin exposure: TWA limit = 0.02 ppm (0.05 mg/m3) & IDLH = 3 ppm

  6. Protective Equipment • Diffuses through polyethylene and attacks most elastomers • Wear protective clothing appropriate to the type and degree of contamination • Positive-pressure, self-contained breathing apparatus (SCBA) is recommended

  7. Detection • No automated detection devices found

  8. Decontamination • Remove victims from the area of exposure, provide 100% O2 if inhalation has occurred • Remove and double-bag contaminated clothing and personal belongings

  9. Decontamination • Eyes • Flush with lukewarm water, 15 minutes • Remove contact lenses • Skin • Flush skin and hair with water, 5 minutes • Wash with soap and water, 15 minutes • Rinse thoroughly

  10. Signs and Symptoms • Early effects of acute inhalation gaseous exposure • Eye exposure: various adverse effects • Continued exposure • Difficulty breathing and cough develops • Acute pulmonary edema and even acute respiratory distress syndrome

  11. Signs and Symptoms • Skin irritant causing a burning sensation • Absorbed through the skin

  12. Signs and Symptoms • Highly toxic with oral exposure • Reaches most organs in active form • Systemic effects seen in animal studies • Other systemic symptoms: nausea, gastritis, sweating, fever, and chills

  13. Signs and Symptoms • Bhopal accident • Burning eyes most frequent symptom • Cough associated with poor prognosis • Other symptoms include diarrhea, shortness of breath • Many deaths from secondary infections • Severe changes in lung function, renal tubular necrosis, reduced liver function

  14. Treatment • Basic first aid for victim • Primarily supportive treatment • Treat pulmonary irritation and maintain adequate ventilation and oxygenation

  15. Treatment • Oral exposures • Administer activated charcoal slurry (240 mL water / 30 gm charcoal) • 25 to 100gm in adults and adolescents • 25 to 50gm in children ages 1 to 12 years • 1 gm/kg in infants less than 1 year old • A cathartic may be beneficial

  16. Treatment • Eye exposure • Liquid • Extremely irritating • May cause permanent damage • Gas • Irritating • Rarely causes permanent injury

  17. Treatment • Eye exposure • Corneal abrasions • Mydriatics, systemic analgesics, and topical ophthalmic antibiotics • Severe iritis • Topical atropine or homatropine

  18. Treatment • Dermal exposure • Extremely irritating • Treat topically • Dermal hypersensitivity reactions • Systemic or topical corticosteroids or antihistamines

  19. Treatment • Inhalation • Oxygen, ventilatory support, and an intravenous line • For bronchospasm: inhaled and/or parenteral sympathomimetics, IV theophylline, and steroids • Hospitalize and observe all symptomatic patients for 72 hours for possible delayed pulmonary edema

  20. Treatment • Inhalation • Pulmonary edema • Maintain ventilation and oxygenation • Frequent ABGs or pulse oximetry • Control hypoxia with O2 supplementation • IPPB, PEEP mask or intubation

  21. Treatment • Symptomatic patients • ECG • Chest x-ray • Pulse oximetry • Peak air flows • Arterial blood gases • Serum electrolytes • Renal and hepatic function

  22. Long-Term Medical Sequelae • Bhopal accident • Chronic eye problems • Pulmonary damage • Reproductive effects • EPA Group D • Not classifiable as to human carcinogenicity • Teratogenicity not defined

  23. Environmental Sequelae • Rapidly hydrolyzes when released to moist soil or to water • Volatilization from dry near-surface soil or surfaces is likely • Bioconcentration, volatilization and absorption not significant processes

  24. Summary • Difficult to make and safely store • Less likely to be a terrorist weapon • Immediate danger to life and health by inhalation or oral exposure • Eye irritation to full-blown ARDS, and numerous serious systemic effects

  25. Summary • Supportive treatment • Treat pulmonary irritation and maintain adequate ventilation and oxygenation • 1984 accidental release in Bhopal, India provides long-term medical consequences data

More Related