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Chemical Disasters

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Chemical Disasters

  1. 1. Chemical Disasters Heather Melendez Professor Beam Chem 50H
  2. 2. Global and Individual Perspectives • Most incidents go unreported unless serious damage to people of the environment is involved • We live in a society dependent on chemical reactions to manufacture everything from the food we eat to the cleaning products we use • Many chemical disasters have been devastating to the world that require accountability not cover ups • Even in our own communities, chemical incidents occur daily
  3. 3. Global: Bhopal Disaster • Around 1:00 am on Monday December 3, 1984 • In the City of Bhopal in Central India • A highly toxic cloud of Methyl Isocyanate was released from the chimney stacks of the Union Carbide Pesticide Plant • 2,500 people died immediately • Over 200,000 people were injured and people are still affected to this day with deformities and cancer
  4. 4. Causes • A storage tank containing Methyl Isocyanate (MIC), which is used to make the insecticide Carbaryl was exposed to water that leaked into the storage tank containing 40 cubic meters of MIC • When H2O and MIC mixed an exothermic chemical reaction occurred causing a safety valve to burst due to the pressure and released 20-30 tons of MIC into the atmosphere within 1 hour
  5. 5. Products and Reactions • Methylamine (1) reacts with phosgene (2) producing methyl isocyanate (3) which reacts with 1-naphthol (4) to yield carbaryl (5) • Night of Disaster • 2CH3NCO + H2O ---> C3H8N2O + CO2 + heat • Methyl isocyanate + water yields 1,3-dimethylurea + carbon dioxide and heat • CH3NCO + C3H8N2O ---> C5H11N3O2 + heat
  6. 6. Reasons and Solutions • Poorly designed safety system and working equipment • To save money a portion of the safety equipment had not been operational in 4 months • The hazardous manufacturing plant was built near a highly populated city • Green Chemistry Principles need to be implemented • Hazardous chemicals like MIC need to be stored in smaller containers • Reduce the production of toxic chemicals and use the chemicals during the course of the reaction instead of storing large amounts • Finding alternatives to toxic chemicals to use for insecticides
  7. 7. National: IHOP incident • At 9:15 am on February 17, 2012 • At an IHOP restaurant in South Charleston, West Virginia • A toxic cloud of Chloramine gas spread throughout the restaurant • 50 people had respiratory injuries • 9 people’s injuries were severe enough to be hospitalized
  8. 8. Causes • A kitchen employee mixed chlorine bleach and a delimer, which contained ammonia as its main ingredient, to clean a dishwashing machine • The mixture of the two chemicals created a chemical reaction producing the poisonous Chloramine NH2Cl vapor that spread through the restaurant
  9. 9. Products and Reactions • The NaOCl Sodium Hypochlorite bleach decomposed to form HOCl Hypochlorous acid, which reacts ammonia to form toxic Chloramine fumes • NaOCl → NaOH + HOCL • HOCl → HCl +O • Then the Ammonia NH3 and Chlorine gas Cl2 react to form Chloramine NH2CL , which is released as a vapor • NaOCL + 2HCl → Cl2 + NaCl + H2O • 2NH3 + Cl2 → 2NH2Cl
  10. 10. Consequences • U.S. Occupational Safety and Health Administration cited the IHOP restaurant for 5 alleged serious safety and health violations • Failure to provide training, safety assessments, protective eye wear, eyewash facilities, and display of MSDS information for chemical in the workplace • The key to avoiding such incidents is education and the use of proper safety equipment, such as gloves and protective eyewear, or this can happen
  11. 11. Solutions • Using environmentally friendly green chemical cleaners • Reading chemical warning labels thoroughly • Wearing protective gloves and glasses
  12. 12. Local: UCLA Laboratory Fire • One of the most infamous chemical accidents in a college laboratory resulting in death occurred on December 29, 2008 • Research assistant, Sheri Sangji, worked in the UCLA chemistry laboratory testing a reaction she had previously tested in the attempt to produce more product. • She had detailed lab notes for the procedure • However fatal mistakes were made costing her life
  13. 13. Products and Reactions • Sangji planned to generate vinyllithium by reacting vinyl bromide with two equivalents of tert-butyllithium, t-BuLi, as the first step of a larger synthesis. • t-BuLi is a pyrophoric chemical, which ignites spontaneously in the presence of oxygen • t-BuLi + O2 → t-BuOOLi t-BuLi + H2O → t-BuH + LiOH
  14. 14. Causes • As Sangji was drawing up approximately 50 mL of t-BuLi in a 60 mL plastic syringe, the plunger came out of the barrel and the t-BuLi was exposed to the air igniting into flames • Also in the fume hood was an open flask of hexane, which she knocked over when the t- BuLi reacted and it ignited the solvent catching her synthetic sweater on fire • Instead of using the safety shower, another researcher tried to help by wrapping a lab coat around her to put the fire out, but it caught on fire
  15. 15. Solutions • Follow proper procedure including wearing proper protective wear and check that all equipment is functioning properly • Make sure all chemicals from previous work is cleaned up and stored properly • Be thoroughly educated as to what dangerous reactions can occur if the wrong chemicals are combined • When an emergency in the lab happens do not panic, follow emergency protocol by using the safety showers and eye wash stations
  16. 16. Green Chemistry • The lesson that can be learned from these chemical disasters are: • Use proper protective equipment • Have regulations being followed and safety equipment in proper working order • Being educated about the chemicals being used, we can avoid injuries and death • Going green in chemistry and finding new alternatives to antiquated chemical products is by far the healthiest change that can be made for people and the environment
  17. 17. Works Cited Baxter, Ann, Michael Hyland, Sarah Sager, and Brooks Jarosz. "UPDATE: OSHA Cites South Charleston IHOP for Chlorine Incident." WSAZ RSS. Gray Digital Media, 2 May 2012. Web. 04 Nov. 2013. Gregory, Kathryn. "Chemical Cloud at IHOP; 9 Hospitalized ." Chemical Cloud at IHOP; 9 Hospitalized - News - The Charleston Gazette - West Virginia News and Sports -. Wvgazette.com, 17 Feb. 2012. Web. 04 Nov. 2013. Helmenstine, Ph.D., Anne M. "Why You Shouldn't Mix Bleach and Ammonia - Bleach and Ammonia Chemical Reactions." About.com Chemistry. About.com/chemistry, 20 Aug. 2010. Web. 04 Nov. 2013. Distinguished Member, Expert. "Chemical Forum - Chemistry Help :: View Topic - Bhopal - Balanced Equation." Chemical Forum - Chemistry Help :: View Topic - Bhopal - Balanced Equation. Chemicalforum.webqc.org, 22 Feb. 2011. Web. 04 Nov. 2013. Kemsley, Jyllian N. "Learning From UCLA." CEN RSS. American Chemical Society, 3 Aug. 2009. Web. 04 Nov. 2013. "Tert-Butyllithium." Wikipedia. Wikimedia Foundation, 17 Oct. 2013. Web. 04 Nov. 2013. Vijayan, V. K. (2010). Methyl isocyanate (MIC) exposure and its consequences on human health at Bhopal. International Journal Of Environmental Studies, 67(5), 637-653.