Common Name: Methyl Chloride CAS Number: 74-87-3 DOT Number: UN 1063 Date: October, 1986 ----------------------------------------- HAZARD SUMMARY * Methyl Chloride can affect you when breathed in and by passing through your skin. * Long term exposure to Methyl Chloride may damage the testes. * Higher levels can cause dizziness, drowsiness, unconsciousness, convulsions, and death. * Exposure can cause blurred or double vision, and a "drunken" behavior. * Methyl Chloride is a HIGHLY FLAMMABLE GAS and a DANGEROUS FIRE HAZARD. IDENTIFICATION Methyl Chloride is a colorless gas with a faint sweet odor. It is stored as a liquid in compressed gas cylinders. It is used as a refrigerant and in making other chemicals. REASON FOR CITATION * Methyl Chloride is on the RTK Hazardous Substance List because it is regulated by OSHA and cited by ACGIH, DOT and NFPA. * This chemical is on the Special Health Hazard Substance List because it is FLAMMABLE. * Definitions are attached. HOW TO DETERMINE IF YOU ARE BEING EXPOSED * Exposure to hazardous substances should be routinely evaluated. This may include collecting personal and area air samples. You can obtain copies of sampling results from your employer. You have a legal right to this information under OSHA 1910.20. * ODOR THRESHOLD = 10 ppm. * If you think you are experiencing any work related health problems, see a doctor trained to recognize occupational diseases. Take this Fact Sheet with you. * The odor threshold only serves as a warning of exposure. Not smelling it does not mean you are not being exposed. WORKPLACE EXPOSURE LIMITS OSHA: The legal permissible exposure limit (PEL) is 100 ppm averaged over an 8 hour workshift, with a ceiling level of 200 ppm and a maximum acceptable peak of 300 ppm for 5 minutes in any 3 hour period. ACGIH: The recommended exposure limit is 50 ppm averaged over an 8 hour workshift and 100 ppm as a STEL (short term exposure limit). * The above exposure limits are for air levels only. When skin contact also occurs, you may be overexposed, even though air levels are less than the limits listed above. WAYS OF REDUCING EXPOSURE * Where possible, enclose operations and use local exhaust ventilation at the site of chemical release. If local exhaust ventilation or enclosure is not used, respirators should be worn. * Wear protective work clothing. * Wash thoroughly at the end of the work shift. * Post hazard and warning information in the work area. In addition, as part of an ongoing education and training effort, communicate all information on the health and safety hazards of Methyl Chloride to potentially exposed workers. This Fact Sheet is a summary source of information of all potential and most severe health hazards that may result from exposure. Duration of exposure, concentration of the substance and other factors will affect your susceptibility to any of the potential effects described below. ------------------------------------------ HEALTH HAZARD INFORMATION Acute Health Effects The following acute (short term) health effects may occur immediately or shortly after exposure to Methyl Chloride: * Contact with the liquified gas can cause frostbite and severe eye burns, leading to permanent damage. * Exposure can cause blurred or double vision, and "drunken" behavior. * Higher levels can cause dizziness, drowsiness, unconsciousness, convulsions, and death. These effects may not appear until several hours later. * Methyl Chloride can cause nausea, vomiting, and diarrhea. * It may damage the liver and kidneys. * Very high levels may cause a buildup of fluid in the lungs (pulmonary edema). This can cause death. Chronic Health Effects The following chronic (long term) health effects can occur at some time after exposure to Methyl Chloride and can last for months or years: Cancer Hazard * There is limited evidence that Methyl Chloride causes cancer in animals. Reproductive Hazard * Long term exposure to Methyl Chloride may affect the testes (male reproductive glands), causing decreased production of male hormones and sperm. Other Long Term Effects * Methyl Chloride may damage the liver, kidneys, and blood forming organs. * Long term exposure can interfere with brain function, causing clumsiness, headache, dizziness, poor judgment and memory, slurred speech, sleep disturbances and personality changes (depression, irritability). * Exposure can cause blurred or double vision. * Very irritating substances may affect the lungs. It is not known whether Methyl Chloride causes lung damage. MEDICAL Medical Testing For those with frequent or potentially high exposure (half the TLV or greater, or significant skin contact), the following are recommended before beginning work and at regular times after that: * Lung function tests. * Exam of the nervous system. If symptoms develop or overexposure is suspected, the following may be useful: * Exam of the nervous system. * Kidney function tests. * Liver function tests. * Consider chest x ray after acute over exposure. * Complete blood count. Any evaluation should include a careful history of past and present symptoms with an exam. Medical tests that look for damage already done are not a substitute for controlling exposure. Request copies of your medical testing. You have a legal right to this information under OSHA 1910.20. WORKPLACE CONTROLS AND PRACTICES Unless a less toxic chemical can be substituted for a hazardous substance, ENGINEERING CONTROLS are the most effective way of reducing exposure. The best protection is to enclose operations and/or provide local exhaust ventilation at the site of chemical release. Isolating operations can also reduce exposure. Using respirators or protective equipment is less effective than the controls mentioned above, but is sometimes necessary. In evaluating the controls present in your workplace, consider: (1) how hazardous the substance is, (2) how much of the substance is released into the workplace and (3) whether harmful skin or eye contact could occur. Special controls should be in place for highly toxic chemicals or when significant skin, eye, or breathing exposures are possible. In addition the following controls are recommended: * Where possible, automatically pump liquid Methyl Chloride from drums or other storage containers to process containers. * Before entering a confined space where Methyl Chloride may be present, check to make sure that an explosive concentration does not exist. Good WORK PRACTICES can help to reduce hazardous exposures. The following work practices are recommended: * Workers whose clothing has been contaminated by liquid Methyl Chloride should change into clean clothing promptly. * On skin contact with liquid Methyl Chloride, immediately wash or shower to remove the chemical. * Eye wash fountains should be provided in the immediate work area for emergency use when working with liquified gas. * Do not eat, smoke, or drink where Methyl Chloride is handled, processed, or stored, since the chemical can be swallowed. Wash hands carefully before eating or smoking. PERSONAL PROTECTIVE EQUIPMENT WORKPLACE CONTROLS ARE BETTER THAN PERSONAL PROTECTIVE EQUIPMENT. However, for some jobs (such as outside work, confined space entry, jobs done only once in a while, or jobs done while workplace controls are being installed), personal protective equipment may be appropriate. The following recommendations are only guidelines and may not apply to every situation. Clothing * Avoid skin contact with Methyl Chloride. Wear protective gloves and clothing. Safety equipment suppliers/ manufacturers can provide recommendations on the most protective glove/ clothing material for your operation. * All protective clothing (suits, gloves, footwear, headgear) should be clean, available each day, and put on before work. * ACGIH recommends Neoprene as fair to good protective material. Eye Protection * Wear splash proof chemical goggles and face shield when working with liquid, unless full facepiece respiratory protection is worn. * Wear gas proof goggles, unless full facepiece respiratory protection is worn. Respiratory Protection IMPROPER USE OF RESPIRATORS IS DANGEROUS. Such equipment should only be used if the employer has a written program that takes into account workplace conditions, requirements for worker training, respirator fit testing and medical exams, as described in OSHA 1910.134. * Where the potential exists for exposures over 50 ppm, use a MSHA/NIOSH approved supplied air respirator with a full facepiece operated in the positive pressure mode or with a full facepiece, hood, or helmet in the continuous flow mode, or use a MSHA/NIOSH approved self contained breathing apparatus with a full facepiece operated in pressure demand or other positive pressure mode. * Exposure to 10,000 ppm is immediately dangerous to life and health. If the possibility of exposures above 10,000 ppm exists, use a MSHA/NIOSH approved self contained breathing apparatus with a full facepiece operated in continuous flow or other positive pressure mode. HANDLING AND STORAGE * Prior to working with Methyl Chloride you should be trained on its proper handling and storage. * Methyl Chloride must be stored to avoid contact with OXIDIZERS (such as PERCHLORATES, PEROXIDES, CHLORATES, NI TRATES, and PERMANGANATES) or CHEMICALLY ACTIVE METALS (such as SODIUM, POTASSIUM, POWDERED ALUMINUM, ZINC, and MAGNESIUM) since violent reactions occur. * Store in tightly closed containers in a cool well ventilated area away from HEAT and DIRECT SUNLIGHT. * Sources of ignition such as smoking and open flames are prohibited where Methyl Chloride is used, handled, or stored in a manner that could create a potential fire or explosion hazard. * Wherever Methyl Chloride is used, handled, manufactured, or stored, use explosion proof electrical equipment and fittings. Common Name: Methyl Chloride DOT Number: UN 1063 DOT Emergency Guide code: 18 CAS Number: 74-87-3 ---------------------------------------- NJ DOH Hazard rating FLAMMABILITY 4 REACTIVITY 0 ---------------------------------------- FLAMMABLE GAS POISONOUS GASES ARE PRODUCED IN FIRE ---------------------------------------- Hazard Rating Key: 0=minimal; 1=slight; 2=moderate; 3=serious; 4=severe FIRE HAZARDS * Methyl Chloride is a FLAMMABLE GAS. To extinguish fire, stop the flow of gas; use water to keep fire exposed cylinders cool. * POISONOUS GASES ARE PRODUCED IN FIRE, including Hydrogen Chloride. * The vapor is heavier than air and may travel a distance to cause a fire or explosion far from the source. * If employees are expected to fight fires, they must be trained and equipped as stated in OSHA 1910.156. SPILLS AND EMERGENCIES If Methyl Chloride is leaked, take the following steps: * Restrict persons not wearing protective equipment from area of leak until cleanup is complete. * Remove all ignition sources. * Ventilate area of leak to disperse the gas. * Stop flow of gas. If source of leak is a cylinder and the leak cannot be stopped in place, remove the leaking cylinder to a safe place in the open air, and repair leak or allow cylinder to empty. * It may be necessary to contain and dispose of Methyl Chloride as a HAZARDOUS WASTE. Contact your state Environmental Program for specific recommendations. ========================================== FOR LARGE SPILLS AND FIRES immediately call your fire department. ========================================== FIRST AID POISON INFORMATION Eye Contact * If liquified Methyl Chloride gets into the eyes, immediately flush with large amounts of water for at least 15 minutes, occasionally lifting the upper and lower lids. Seek medical attention. Skin Contact * If liquified Methyl Chloride gets onto the skin, quickly remove contaminated clothing. Immediately wash area with large amounts of soap and warm water. If frostbite is suspected, immerse affected parts in warm water. Seek medical attention immediately. Breathing * Remove the person from exposure. * Begin rescue breathing if breathing has stopped and CPR if heart action has stopped. * Transfer promptly to a medical facility. * Medical observation is recommended for 24 to 48 hours after breathing overexposure, as pulmonary edema may be de layed. PHYSICAL DATA Vapor Pressure: 3,648 mm Hg at 68oF Water Solubility: Insoluble OTHER COMMONLY USED NAMES Chemical Name: Chloromethane Other Names and Formulations: Monochloromethane; Artic; R 40. ------------------------------------------ Not intended to be copied and sold for commercial purposes. ------------------------------------------ NEW JERSEY DEPARTMENT OF HEALTH Right to Know Program CN 368, Trenton, NJ 08625 0368 ------------------------------------------ ----------------------------------------- ECOLOGICAL INFORMATION Methyl Chloride is a colorless gas used as a refrigerant, methylating agent, dewaxing agent, and catalytic solvent in synthetic rubber production. It is also used as a chemical intermediate for gasoline antiknock additives, herbicides, and plastics. Methyl Chloride is highly volatile with much of the chemical escaping to the atmosphere from water. It may enter the aquatic environment from industrial discharges. ACUTE (SHORT-TERM) ECOLOGICAL EFFECTS Acute toxic effects may include the death of animals, birds, or fish, and death or low growth rate in plants. Acute effects are seen two to four days after animals or plants come in contact with a toxic chemical substance. Methyl Chloride has slight acute toxicity to aquatic life. Insufficient data are available to evaluate or predict the short- term effects of methyl chloride to plants, birds, or land animals. CHRONIC (LONG-TERM) ECOLOGICAL EFFECTS Chronic toxic effects may include shortened lifespan, reproductive problems, lower fertility, and changes in appearance or behavior. Chronic effects can be seen long after first exposure(s) to a toxic chemical. Methyl Chloride has slight chronic toxicity to aquatic life. Insufficient data are available to evaluate or predict the long- term effects of methyl chloride to plants, birds, or land animals. WATER SOLUBILITY Methyl Chloride is highly soluble in water. Concentrations of 1,000 milligrams and more will mix with a liter of water. DISTRIBUTION AND PERSISTENCE IN THE ENVIRONMENT Methyl Chloride is non-persistent in water, with a half-life of less than 2 days. The half-life of a pollutant is the amount of time it takes for one-half of the chemical to be degraded. About 99.8% of methyl chloride will eventually end up in air; the rest will end up in the water. BIOACCUMULATION IN AQUATIC ORGANISMS Some substances increase in concentration, or bioaccumulate, in living organisms as they breathe contaminated air, drink contaminated water, or eat contaminated food. These chemicals can become concentrated in the tissues and internal organs of animals and humans. The concentration of methyl chloride found in fish tissues is expected to be about the same as the average concentration of methyl chloride in the water from which the fish was taken. SUPPORT DOCUMENT: AQUIRE Database, ERL-Duluth, U.S. EPA.