. "Appendix B: Laboratory Chemical Safety Summaries." Prudent Practices in the Laboratory: Handling and Disposal of Chemicals. Washington, DC: The National Academies Press, 1995.
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Prudent Practices in the Laboratory: Handling and Disposal of Chemicals
Appendix B:Laboratory Chemical Safety Summaries
This appendix presents Laboratory Chemical Safety Summaries (LCSSs) for 88 substances commonly encountered in laboratories. These summaries have been prepared in accord with the general and comprehensive approach to experiment planning and risk assessment that is outlined in Chapters 2 ("Prudent Planning of Experiments") and 3 ("Evaluating Hazards and Assessing Risks in the Laboratory") of this volume, and they should be used only by individuals familiar with the content of those chapters. The scope of coverage and degree of detail provided in these summaries should be appropriate for prudent experiment planning in most commonly encountered laboratory situations. Each summary includes chemical and toxicological information derived from the various secondary sources discussed in Chapter 3, as well as from Material Safety Data Sheets (MSDSs).
The committee encourages the dissemination of these summaries as a means of promoting the prudent use of hazardous chemicals in laboratory work. It anticipates that these summaries will also serve as models for the preparation of additional LCSSs for chemicals not included in this appendix. In fact, the committee recommends that laboratory workers routinely prepare new LCSSs for unfamiliar substances as part of the risk assessment they should carry out for each experiment as outlined at the conclusion ofChapter 3.
The preparation and use of Laboratory Chemical Safety Summaries as described here are consistent with the Chemical Hygiene Plans required for every laboratory under the OSHA Laboratory Standard. Thus, the identification of substances that meet the OSHA criteria for "particularly hazardous substances" or "select carcinogens" should be facilitated by the use of these summaries.
LIMITATIONS OF LCSSs
All users of Laboratory Chemical Safety Summaries should understand their limitations. In each summary, the content of the section on toxicity is dependent on the quality of the information available. For some chemicals the description of toxicity hazards is based on extensive experience with human exposure, while in other cases this discussion is based on limited data from animal tests. If a substance meets the OSHA definition of a "select carcinogen" (based on current information), that fact is noted here. The discussion of toxic effects has been written so as to be comprehensible to the average laboratory worker, with full knowledge that the use of plain language may lead to a lack of precision in the description of toxic effects. The section on reactivity and incompatibility summarizes only those items that are likely to be encountered in normal laboratory use and should not be considered comprehensive. If more extensive information is required for any of the categories of information given in these summaries, the sources listed in Chapter 3 should be consulted. In addition, OSHA regulations (Standards—29 CFR) are now available on the WorldWideWeb, as are further links to safety and health information: http://www.osha.gov/safhlth.html.
These summaries should be used only by laboratory workers with general training in the safe handling of chemicals. LCSSs are intended to be used in conjunction with Chapters 3 through 7 of this volume, and these summaries make frequent reference to the contents of those chapters. The information in these summaries has been selected for its relevance to the laboratory use of chemicals. In particular, the listing of chemicals and toxicological hazards is not intended to be a comprehensive review of the literature for a given substance. These summaries do not contain information on
household or nonlaboratory use of a chemical;
commercial, manufacturing, or other large-scale use of chemicals;
consequences of abuse of a chemical by deliberate ingestion, inhalation, or injection;
environmental effects of release, disposal, or incineration of a chemical; or
shipment or transportation of a chemical in accordance with applicable laws and regulations.
The information contained in these summaries is believed to be accurate at the time of publication of this volume. A recent MSDS should be consulted for updated information, especially on exposure limits.
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Appendix B: Laboratory Chemical Safety Summaries
This appendix presents Laboratory Chemical Safety Summaries (LCSSs) for 88 substances commonly encountered in laboratories. These summaries have been prepared in accord with the general and comprehensive approach to experiment planning and risk assessment that is outlined in Chapters 2 ("Prudent Planning of Experiments") and 3 ("Evaluating Hazards and Assessing Risks in the Laboratory") of this volume, and they should be used only by individuals familiar with the content of those chapters. The scope of coverage and degree of detail provided in these summaries should be appropriate for prudent experiment planning in most commonly encountered laboratory situations. Each summary includes chemical and toxicological information derived from the various secondary sources discussed in Chapter 3, as well as from Material Safety Data Sheets (MSDSs).
The committee encourages the dissemination of these summaries as a means of promoting the prudent use of hazardous chemicals in laboratory work. It anticipates that these summaries will also serve as models for the preparation of additional LCSSs for chemicals not included in this appendix. In fact, the committee recommends that laboratory workers routinely prepare new LCSSs for unfamiliar substances as part of the risk assessment they should carry out for each experiment as outlined at the conclusion of Chapter 3.
The preparation and use of Laboratory Chemical Safety Summaries as described here are consistent with the Chemical Hygiene Plans required for every laboratory under the OSHA Laboratory Standard. Thus, the identification of substances that meet the OSHA criteria for "particularly hazardous substances" or "select carcinogens" should be facilitated by the use of these summaries.
LIMITATIONS OF LCSSs
All users of Laboratory Chemical Safety Summaries should understand their limitations. In each summary, the content of the section on toxicity is dependent on the quality of the information available. For some chemicals the description of toxicity hazards is based on extensive experience with human exposure, while in other cases this discussion is based on limited data from animal tests. If a substance meets the OSHA definition of a "select carcinogen" (based on current information), that fact is noted here. The discussion of toxic effects has been written so as to be comprehensible to the average laboratory worker, with full knowledge that the use of plain language may lead to a lack of precision in the description of toxic effects. The section on reactivity and incompatibility summarizes only those items that are likely to be encountered in normal laboratory use and should not be considered comprehensive. If more extensive information is required for any of the categories of information given in these summaries, the sources listed in Chapter 3 should be consulted. In addition, OSHA regulations (Standards—29 CFR) are now available on the WorldWideWeb, as are further links to safety and health information: http://www.osha.gov/safhlth.html.
These summaries should be used only by laboratory workers with general training in the safe handling of chemicals. LCSSs are intended to be used in conjunction with Chapters 3 through 7 of this volume, and these summaries make frequent reference to the contents of those chapters. The information in these summaries has been selected for its relevance to the laboratory use of chemicals. In particular, the listing of chemicals and toxicological hazards is not intended to be a comprehensive review of the literature for a given substance. These summaries do not contain information on
household or nonlaboratory use of a chemical;
commercial, manufacturing, or other large-scale use of chemicals;
consequences of abuse of a chemical by deliberate ingestion, inhalation, or injection;
environmental effects of release, disposal, or incineration of a chemical; or
shipment or transportation of a chemical in accordance with applicable laws and regulations.
The information contained in these summaries is believed to be accurate at the time of publication of this volume. A recent MSDS should be consulted for updated information, especially on exposure limits.
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PREPARATION OF NEW LCSSs
All of the information required for the preparation of new LCSSs should be available in the sources discussed in Chapter 3. The following directions should be helpful in preparing specific sections of new LCSSs:
Odor: Information on odor and odor thresholds can be found in NIOSH Guidelines, Royal Society Chemical Safety Data Sheets, and in the AIHA publication "Odor Thresholds for Chemicals with Established Occupational Health Standards."
Toxicity data: LD50 and LC50 values can be found in MSDSs and other sources listed in Chapter 3. Exposure limits are included in MSDSs and are listed in the ACGIH Threshold Limit Value booklet, which is updated annually.
Major hazards: This section should provide key words indicating only the most important potential hazards associated with the title substance.
Toxicity: The first paragraph of this section should discuss acute toxicity hazards using plain language. Symptoms of exposure by inhalation, skin contact, eye contact, and ingestion should be separately described, and the degree of hazard of the substance should be identified as "high," "moderate," or "low," as discussed in Chapter 3. The paragraph should indicate whether there are adequate warning properties for the substance. The second paragraph should address chronic toxicity. For potential carcinogens, whether the substance is classified as an OSHA ''select carcinogen" should be indicated.
Flammability and explosibility: This section should indicate the NFPA rating for the substance, explosion limits, toxic substances that may be produced in a fire, and the type of fire extinguisher appropriate for fighting fires.
Storage and handling: This section should make reference to the appropriate sections of Chapter 5 and should also highlight any special procedures of particular importance in work with the title substance.
SECTIONS INCLUDED IN LCSSs
Each of the 88 LCSSs supplied in this appendix includes those of the following sections that apply to the title substance:
Substance,
Formula,
Physical properties,
Odor,
Vapor density,
Vapor pressure,
Flash point,
Autoignition temperature,
Toxicity data,
Major hazards,
Toxicity,
Flammability and explosibility,
Reactivity and incompatibility,
Storage and handling,
Accidents,
Disposal.
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LABORATORY CHEMICAL SAFETY SUMMARIES
Acetaldehyde
Acetic Acid
Acetone
Acetonitrile
Acetylene
Acrolein
Acrylamide
Acrylonitrile
Aluminum Trichloride
Ammonia (Anhydrous)
Ammonium Hydroxide
Aniline
Arsine
Benzene
Boron Trifluoride
Bromine
Tert-Butyl Hydroperoxide
Butyllithiums
Carbon Disulfide
Carbon Monoxide
Carbon Tetrachloride
Chlorine
Chloroform
Chloromethyl Methyl Ether (and Related Compounds)
Chromium Trioxide and Other Chromium(VI) Salts
Cyanogen Bromide
Diazomethane
Diborane
Dichloromethane
Diethyl Ether
Diethylnitrosamine (and Related Nitrosamines)
Dimethyl Sulfate
Dimethyl Sulfoxide
Dimethylformamide
Dioxane
Ethanol
Ethidium Bromide
Ethyl Acetate
Ethylene Dibromide
Ethylene Oxide
Fluorides (Inorganic)
Fluorine
Formaldehyde
Hexamethylphosphoramide
Hexane (and Related Hydrocarbons)
Hydrazine
Hydrobromic Acid and Hydrogen Bromide
Hydrochloric Acid and Hydrogen Chloride
Hydrogen
Hydrogen Cyanide
Hydrogen Fluoride and Hydrofluoric Acid
Hydrogen Peroxide
Hydrogen Sulfide
Iodine
Lead and Its Inorganic Compounds
Lithium Aluminum Hydride
Mercury
Methanol
Methyl Ethyl Ketone
Methyl Iodide
Nickel Carbonyl
Nitric Acid
Nitrogen Dioxide
Osmium Tetroxide
Oxygen
Ozone
Palladium on Carbon
Peracetic Acid (and Related Percarboxylic Acids)
Perchloric Acid (and Inorganic Perchlorates)
Phenol
Phosgene
Phosphorus
Potassium
Potassium Hydride and Sodium Hydride
Pyridine
Silver and Its Compounds
Sodium
Sodium Azide
Sodium Cyanide and Potassium Cyanide
Sodium Hydroxide and Potassium Hydroxide
Sulfur Dioxide
Sulfuric Acid
Tetrahydrofuran
Toluene
Toluene Diisocyanate
Trifluoroacetic Acid
Trimethylaluminum (and Related Organoaluminum Compounds)
Trimethyltin Chloride (and Other Organotin Compounds)
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LABORATORY CHEMICAL SAFETY SUMMARY: ACETALDEHYDE
Substance
Acetaldehyde
(Ethanal, acetic aldehyde)
CAS 75-07-0
Formula
CH3CHO
Physical Properties
Colorless liquid
bp 21 °C, mp -124 °C
Miscible with water
Odor
Pungent, fruity odor detectable at 0.0068 to 1000 ppm (mean = 0.067 ppm)
Vapor Density
1.52 (air = 1.0)
Vapor Pressure
740 mmHg at 20 °C
Flash Point
-38 °C
Autoignition Temperature
185 °C
Toxicity Data
LD50 oral (rat)
661 mg/kg
LC50 inhal (rat)
20,550 ppm (37,000 mg/m3; 30 min)
PEL (OSHA)
200 ppm (360 mg/m3)
TLV-TWA (ACGIH)
100 ppm (180 mg/m3)
STEL (ACGIH)
150 ppm (270 mg/m3)
Major Hazards
Highly flammable liquid; irritating to the eyes and respiratory system.
Toxicity
The acute toxicity of acetaldehyde is low by inhalation and moderate by ingestion. Exposure to acetaldehyde by inhalation is irritating to the respiratory tract and mucous membranes; this substance is a narcotic and can cause central nervous system depression. Ingestion of acetaldehyde may cause severe irritation of the digestive tract leading to nausea, vomiting, headache, and liver damage. Acetaldehyde causes irritation and burning upon skin contact and is a severe eye irritant.
Acetaldehyde has caused nasal tumors in rats exposed by inhalation and is listed by IARC in Group 2B ("possible human carcinogen"). It is not classified as a "select carcinogen" according to the criteria of the OSHA Laboratory Standard. Acetaldehyde is mutagenic and has been shown to be a reproductive toxin in animals. Acetaldehyde is formed by metabolism of ethanol, and chronic exposure can produce symptoms similar to alcoholism.
Flammability and Explosibility
Acetaldehyde is a dangerous fire hazard (NFPA rating = 4) owing to its volatility and low autoignition temperature. Its vapor is explosive in the concentration range 4 to 66% in air and may be ignited by hot surfaces such as hot plates or light bulbs, or by static
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electricity discharges. The vapor is heavier than air and may travel a considerable distance to an ignition source and "flash back." Carbon dioxide or dry chemical extinguishers should be used to fight acetaldehyde fires.
Reactivity and Incompatibility
Acetaldehyde is a reactive substance and on storage in the presence of air may undergo oxidation to form explosive peroxides. It may also polymerize violently when in contact with strong acids or trace metals such as iron. Acetaldehyde may undergo violent reactions with acid chlorides, anhydrides, amines, hydrogen cyanide, and hydrogen sulfide.
Storage and Handling
Acetaldehyde should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented by the additional precautions for dealing with extremely flammable substances (Chapter 5.F). In particular, acetaldehyde should be used only in areas free of ignition sources, and quantities greater than 1 liter should be stored in tightly sealed metal containers in areas separate from oxidizers. Acetaldehyde should always be stored under an inert atmosphere of nitrogen or argon to prevent autoxidation.
Accidents
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If acetaldehyde is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.
In the event of a spill, remove all ignition sources, soak up the acetaldehyde with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Alternatively, acetaldehyde spills may be neutralized with sodium bisulfite solution before cleanup. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Excess acetaldehyde and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
The information in this LCSS has been compiled by a committee of the National Research Council from literature sources and Material Safety Data Sheets and is believed to be accurate as of July 1994. This summary is intended for use by trained laboratory personnel in conjunction with the NRC report Prudent Practices in the Laboratory: Handling and Disposal of Chemicals. This LCSS presents a concise summary of safety information that should be adequate for most laboratory uses of the title substance, but in some cases it may be advisable to consult more comprehensive references. This information should not be used as a guide to the nonlaboratory use of this chemical.
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LABORATORY CHEMICAL SAFETY SUMMARY: ACETIC ACID
Substance
Acetic acid
(Ethanoic acid)
CAS 64-19-7
Formula
CH3COOH
Physical Properties
Colorless liquid
bp 118 °C, mp 17 °C
Miscible in water (100 g/100 mL)
Odor
Strong, pungent, vinegar-like odor detectable at 0.2 to 1.0 ppm
Vapor Density
2.1 (air = 1.0)
Vapor Pressure
11 mmHg at 20 °C
Flash Point
39 °C
Autoignition Temperature
426 °C
Toxicity Data
LD50 oral (rat)
3310 mg/kg
LD50 skin (rabbit)
1060 mg/kg
LC50 inhal (mice)
5620 ppm (1 h)
PEL (OSHA)
10 ppm (25 mg/m3)
TLV-TWA (ACGIH)
10 ppm (25 mg/m3)
STEL (ACGIH)
15 ppm (37 mg/m3)
Major Hazards
Corrosive to the skin and eyes; vapor or mist is very irritating and can be destructive to the eyes, mucous membranes, and respiratory system; ingestion causes internal irritation and severe injury.
Toxicity
The acute toxicity of acetic acid is low. The immediate toxic effects of acetic acid are due to its corrosive action and dehydration of tissues with which it comes in contact. A 10% aqueous solution of acetic acid produced mild or no irritation on guinea pig skin. At 25 to 50%, generally severe irritation results. In the eye, a 4 to 10% solution will produce immediate pain and sometimes injury to the cornea. Acetic acid solutions of 80% or greater concentration can cause serious burns of the skin and eyes. Acetic acid is slightly toxic by inhalation; exposure to 50 ppm is extremely irritating to the eyes, nose, and throat.
Acetic acid has not been found to be carcinogenic or to show reproductive or developmental toxicity in humans.
Flammability and Explosibility
Acetic acid is a combustible substance (NFPA rating = 2). Heating can release vapors that can be ignited. Vapors or gases may travel considerable distances to ignition source
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and "flash back." Acetic acid vapor forms explosive mixtures with air at concentrations of 4 to 16% (by volume). Carbon dioxide or dry chemical extinguishers should be used for acetic acid fires.
Reactivity and Incompatibility
Contact with strong oxidizers may cause fire.
Storage and Handling
Acetic acid should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C. In particular, acetic acid should be used only in areas free of ignition sources, and quantities greater than 1 liter should be stored in tightly sealed metal containers in areas separate from oxidizers.
Accidents
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If acetic acid is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.
In the event of a spill, remove all ignition sources, soak up the acetic acid with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Cleaned-up material is a RCRA Hazardous Waste. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Excess acetic acid and waste material containing this substance should be placed in a covered metal container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
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LABORATORY CHEMICAL SAFETY SUMMARY: ACETONE
Substance
Acetone
(2-Propanone)
CAS 67-64-1
Formula
CH3COCH3
Physical Properties
Colorless liquid
bp 56 °C, mp -94 °C
Miscible with water
Odor
Characteristic pungent odor detectable at 33 to 700 ppm (mean = 130 ppm)
Vapor Density
2.0 (air = 1.0)
Vapor Pressure
180 mmHg at 20 °C
Flash Point
-18 °C
Autoignition Temperature
465 °C
Toxicity Data
LD50 oral (rat)
5800 mg/kg
LD50 skin (rabbit)
20,000 mg/kg
LC50 inhal (rat)
50,100 mg/m3
PEL (OSHA)
1000 ppm (2400 mg/m3)
TLV-TWA (ACGIH)
750 ppm
STEL (ACGIH)
1000 ppm (2400 mg/m3)
Major Hazards
Highly flammable.
Toxicity
The acute toxicity of acetone is low. Acetone is primarily a central nervous system depressant at high concentrations (greater than 12,000 ppm). Unacclimated volunteers exposed to 500 ppm acetone experienced eye and nasal irritation, but it has been reported that 1000 ppm for an 8-hour day produced no effects other than slight transient irritation to eyes, nose, and throat. Therefore there are good warning properties for those unaccustomed to working with acetone; however, frequent use of acetone seems to cause accommodation to its slight irritating properties. Acetone is practically nontoxic by ingestion. A case of a man swallowing 200 mL of acetone resulted in his becoming stuporous after 1 hour and then comatose; he regained consciousness 12 hour later. Acetone is slightly irritating to the skin, and prolonged contact may cause dermatitis. Liquid acetone produces moderate transient eye irritation.
Acetone has not been found to be carcinogenic in animal tests or to have effects on reproduction or fertility.
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Flammability and Explosibility
Acetone is extremely flammable (NFPA rating = 3), and its vapor can travel a considerable distance to an ignition source and "flash back." Acetone vapor forms explosive mixtures with air at concentrations of 2 to 13% (by volume). Carbon dioxide or dry chemical extinguishers should be used for acetone fires.
Reactivity and Incompatibility
Fires and/or explosions may result from the reaction of acetone with strong oxidizing agents (e.g., chromium trioxide) and very strong bases (e.g., potassium t-butoxide).
Storage and Handling
Acetone should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented by the additional precautions for dealing with extremely flammable substances (Chapter 5.F). In particular, acetone should be used only in areas free of ignition sources, and quantities greater than 1 liter should be stored in tightly sealed metal containers in areas separate from oxidizers.
Accidents
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If acetone is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.
In the event of a spill, remove all ignition sources, soak up the acetone with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Excess acetone and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
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Substance
Acetonitrile
(Methyl cyanide, cyanomethane)
CAS 75-05-8
Formula
H3C-C=N
Physical Properties
Colorless liquid
bp 82 °C, mp - 46°C
Miscible with water (>100 g/100 mL)
Odor
Aromatic ether-like odor detectable at 40 ppm
Vapor Density
1.42 (air = 1.0)
Vapor Pressure
73 mmHg at 20 °C
Flash Point
6 °C
Autoignition Temperature
524 °C
Toxicity Data
LD50 oral (rat)
LD30 mg/kg
LD50 skin (rabbit)
1250 mg/kg
LC50 inhal (rat)
7551 ppm (8 h)
PEL (OSHA)
40 ppm (70 mg/m3)
STEL (OSHA)
60 ppm (105 mg/m3)
TLV-TWA (ACGIH)
40 ppm (70 mg/m3)
STEL (ACGIH)
60 ppm (105 mg/m3)
Major Hazards
Flammable liquid and vapor; liquid severely irritates the eyes.
Toxicity
Acetonitrile is slightly toxic by acute exposure through oral intake, skin contact, and inhalation. However, acetonitrile can be converted by the body to cyanide. Symptoms of exposure include weakness, flushing, headache, difficult and/or rapid breathing, nausea, vomiting, diarrhea, blue-gray discoloration of the skin and lips (due to a lack of oxygen), stupor, and loss of consciousness. Acetonitrile is severely irritating to the eyes and slightly irritating to the skin. Prolonged contact can lead to absorption through the skin and more intense irritation. Acetonitrile is regarded as having adequate warning properties.
Acetonitrile is not mutagenic in bacterial and animal cells and has not been found to be a carcinogen in humans. Single high-dose exposure in animals during pregnancy produced birth defects possibly due to the liberation of cyanide. Multiple oral doses during pregnancy did not produce birth defects. Repeated exposure in animals produced adverse lung effects.
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Flammability and Explosibility
Acetonitrile is a flammable liquid (NFPA rating = 3), and its vapor can travel a considerable distance to an ignition source and "flash back." Acetonitrile vapor forms explosive mixtures with air at concentrations of 4 to 16% (by volume). Hazardous gases produced in a fire include hydrogen cyanide, carbon monoxide, carbon dioxide, and oxides of nitrogen. Carbon dioxide or dry chemical extinguishers should be used for acetonitrile fires.
Reactivity and Incompatibility
Contact of acetonitrile with strong oxidizers can result in violent reactions. Acetonitrile hydrolyzes on exposure to strong acids and bases. It is incompatible with reducing agents and alkali metals and may attack plastics, rubber, and some coatings.
Storage and Handling
Acetonitrile should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented by the additional precautions for dealing with highly flammable substances (Chapter 5.F). In particular, acetonitrile should be used only in areas free of ignition sources, and quantities greater than 1 liter should be stored in tightly sealed metal containers in areas separate from oxidizers.
Accidents
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If acetonitrile is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.
In the event of a spill, remove all ignition sources, soak up the acetonitrile with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Evacuation and cleanup using respiratory and skin protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Excess acetonitrile and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
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LABORATORY CHEMICAL SAFETY SUMMARY: TOLUENE
Substance
Toluene
(Methylbenzene, toluol, phenylmethane)
CAS 108-88-3
Formula
C6H5CH3
Physical Properties
Colorless liquid
bp 111 °C, mp -95 °C
Poorly soluble in water (0.05 g/100 mL)
Odor
Aromatic, benzene-like odor detectable at 0.16 to 37 ppm (mean = 1.6 ppm)
Vapor Density
3.14 (air = 1.0)
Vapor Pressure
22 mmHg at 20 °C
Flash Point
4 °C
Autoignition Temperature
480 °C
Toxicity Data
LD50 oral (rat)
2650 to 7530 mg/kg
LD50 skin (rabbit)
12,124 mg/kg
LC50 inhal (rat)
26,700 ppm (1 h)
PEL (OSHA)
200 ppm (750 mg/m3)
STEL (OSHA)
150 ppm (560 mg/m3)
TLV-TWA (ACGIH)
50 ppm (188 mg/m3)—skin
Major Hazards
Highly flammable liquid and vapor.
Toxicity
The acute toxicity of toluene is low. Toluene may cause eye, skin, and respiratory tract irritation. Short-term exposure to high concentrations of toluene (e.g., 600 ppm) may produce fatigue, dizziness, headaches, loss of coordination, nausea, and stupor; 10,000 ppm may cause death from respiratory failure. Ingestion of toluene may cause nausea and vomiting and central nervous system depression. Contact of liquid toluene with the eyes causes temporary irritation. Toluene is a skin irritant and may cause redness and pain when trapped beneath clothing or shoes; prolonged or repeated contact with toluene may result in dry and cracked skin. Because of its odor and irritant effects, toluene is regarded as having good warning properties.
The chronic effects of exposure to toluene are much less severe than those of benzene. No carcinogenic effects were reported in animal studies. Equivocal results were obtained in studies to determine developmental effects in animals. Toluene was not observed to be mutagenic in standard studies.
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Flammability and Explosibility
Toluene is a flammable liquid (NFPA rating = 3), and its vapor can travel a considerable distance to an ignition source and "flash back." Toluene vapor forms explosive mixtures with air at concentrations of 1.4 to 6.7% (by volume). Hazardous gases produced in fire include carbon monoxide and carbon dioxide. Carbon dioxide and dry chemical extinguishers should be used to fight toluene fires.
Reactivity and Incompatibility
Contact with strong oxidizers may cause fires and explosions.
Storage and Handling
Toluene should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented by the additional precautions for dealing with highly flammable substances (Chapter 5.F). In particular, toluene should be used only in areas free of ignition sources, and quantities greater than 1 liter should be stored in tightly sealed metal containers in areas separate from oxidizers.
Accidents
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If toluene is ingested, do not induce vomiting. Obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.
In the event of a spill, remove all ignition sources, soak up the toluene with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Excess toluene and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
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LABORATORY CHEMICAL SAFETY SUMMARY: TOLUENE DIISOCYANATE
Substance
Toluene diisocyanate
(TDI; 2,4-toluene diisocyanate; 2,4-diisocyanato-1-methyl benzene)
CAS 584-84-9
Formula
C9H6N2O2
Physical Properties
Colorless to pale yellow liquid
bp 251 °C, mp 21 °C
Insoluble in water (reacts exothermically)
Odor
Sharp, pungent odor detectable at 0.02 to 0.4 ppm
Vapor Density
6.0 (air = 1.0)
Vapor Pressure
0.05 mmHg at 25 °C
Flash Point
132 °C
Autoignition Temperature
>619 °C
Toxicity Data
LD50 oral (rat)
4130 mg/kg
LD50 skin (rabbit)
>10 g/kg
LC50 inhal (rat)
14 ppm/4 h (100 mg/m3; 4 h)
PEL (OSHA)
0.02 ppm(ceiling 0.14 mg/m3)
TLV-TWA (ACGIH)
0.005 ppm (0.036 mg/m3)
STEL (ACGIH)
0.02 ppm (0.14 mg/m3)
Major Hazards
Sensitizer by inhalation and skin contact; possible human carcinogen (OSHA "select carcinogen").
Toxicity
The acute toxicity of toluene diisocyanate by inhalation is high. Exposure to TDI can cause lung damage and decreased breathing capacity. Symptoms of exposure may include coughing, tightness of the chest, chest pain, nausea, vomiting, abdominal pain, headache, and insomnia. TDI irritates the skin, and eye contact can cause irritation with permanent damage if untreated. The oral acute toxicity of this substance is low. The odor of TDI does not provide an adequate warning to avoid overexposure.
Toluene diisocyanate has caused sensitization of the respiratory tract, manifested by acute asthmatic reaction upon return to work after a period of time away from exposure. Initial symptoms include coughing during the night, with difficult or labored breathing. Skin sensitization can also occur. Toluene diisocyanate is listed in IARC Group 2B ("possible human carcinogen"), is listed by NTP as "reasonably anticipated to be a carcinogen," and is classified as a "select carcinogen'' under the criteria of the OSHA Laboratory Standard.
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Flammability and Explosibility
TDI is a combustible liquid (NFPA rating = 1). Explosive limits in air are 0.9 to 9.5% by volume. Carbon dioxide or dry chemical extinguishers should be used for TDI fires.
Reactivity and Incompatibility
Contact with strong oxidizers may cause fires and explosions. Contact with water, acids, bases, and amines can lead to reactions that liberate heat and CO2 and cause violent foaming and spattering. TDI will attack some forms of plastic, rubber, and coatings.
Storage and Handling
Because of its high toxicity, carcinogenicity, and ability to cause sensitization, toluene diisocyanate should be handled using the "basic prudent practices" of Chapter 5.C, supplemented by the additional precautions for work with compounds of high toxicity (Chapter 5.D). In particular, work with TDI should be conducted in a fume hood to prevent exposure by inhalation, and splash goggles and impermeable gloves should be worn at all times to prevent eye and skin contact.
Accidents
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If TDI is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.
In the event of a spill, remove all ignition sources, soak up the TDI with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Excess TDI and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
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LABORATORY CHEMICAL SAFETY SUMMARY: TRIFLUOROACETIC ACID
Substance
Trifluoroacetic acid
(TFA, trifluoroethanoic acid)
CAS 76-05-1
Formula
CF3COOH
Physical Properties
Colorless liquid
bp 72 °C, mp -15 °C
Miscible with water
Odor
Sharp, pungent odor
Vapor Density
3.9 (air = 1.0)
Vapor Pressure
107 mmHg at 25 °C
Flash Point
Noncombustible
Toxicity Data
LD50 oral (rat)
200 mg/kg
LC50 inhal (rat)
2000 ppm (4 h)
Major Hazards
Corrosive to the skin and eyes; vapor or mist is very irritating and can be destructive to the eyes and respiratory system; ingestion causes internal irritation and severe injury.
Toxicity
Trifluoroacetic acid is a highly corrosive substance. Contact of the liquid with the skin, eyes, and mucous membranes can cause severe burns, and ingestion can result in serious damage to the digestive tract. TFA vapor is highly irritating of the eyes and respiratory tract, and inhalation of high concentrations can lead to severe destruction of the upper respiratory tract and may be fatal as a result of pulmonary edema. Symptoms of overexposure to TFA vapor include a burning feeling, coughing, headache, nausea, and vomiting.
Trifluoroacetic acid has not been found to be carcinogenic or to show reproductive or developmental toxicity in humans.
Flammability and Explosibility
Trifluoroacetic acid is not combustible. Nevertheless, the presence of trifluoroacetic acid at the site of a fire would be of great concern because of its high vapor pressure and extreme corrosiveness.
Reactivity and Incompatibility
Mixing trifluoroacetic acid and water evolves considerable heat
Storage and Handling
Trifluoroacetic acid should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C. In particular, trifluoroacetic acid should be stored in an acid cabinet away from other classes of compounds. Because of its high vapor pressure,
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fumes of trifluoroacetic acid can destroy labels on other bottles if the container is not tightly sealed.
Accidents
In the event of skin contact, the affected area should be flushed immediately with copious amounts of water. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally). Medical attention should be obtained immediately in the event of contact with a large area of the skin or eye contact. If trifluoroacetic acid is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.
Carefully neutralize small spills of TFA with a suitable agent such as sodium carbonate, dilute with absorbent material, place in an appropriate container, and dispose of properly. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Trifluoroacetic acid and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
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LABORATORY CHEMICAL SAFETY SUMMARY: TRIMETHYLALUMINUM
(AND RELATED ORGANOALUMINUM COMPOUNDS)
Substance
Trimethylaluminum (and related organoaluminum compounds)
(Trimethylalane, trimethylaluminium)
CAS 75-24-1
Note: Although other alkylaluminum reagents may have different physical properties than trimethylaluminum, their toxicology and reactivity are similar.
Formula
(CH3)3Al
Physical Properties
Colorless pyrophoric liquid
bp 125 to 126 °C, mp 15 °C
React explosively with water
Odor
Corrosive odor and "taste" may be detectable from trimethylaluminum fires
Vapor Density
Not available
Vapor Pressure
12 mmHg at 25 °C
Flash Point
-18 °C
Autoignition Temperature
Spontaneously ignites in air (even as a frozen solid)
Toxicity Data
TLV-TWA (ACGIH)
2 mg (Al)/m3
Major Hazards
Highly reactive, pyrophoric substances; corrosive on contact with skin and eyes.
Toxicity
Trimethylaluminum and related alkylaluminum reagents are pyrophoric materials that can react explosively with the moisture in tissues, causing severe burns. The heat of reaction can also ignite the methane gas generated, resulting in thermal burns. Alkylaluminum reagents are corrosive substances, and contact is extremely destructive to the eyes, skin, and mucous membranes. Inhalation of trimethylaluminum and other volatile alkylaluminum compounds may cause severe damage to the respiratory tract and can lead to fatal pulmonary edema.
Flammability and Explosibility
Trimethylaluminum is pyrophoric and burns violently on contact with air or water. Other alkylaluminum reagents show similar behavior, although most are not as volatile as trimethylaluminum. Water or CO2 fire extinguishers must not be used to put out fires involving trialkylaluminum reagents. Instead, dry chemical powders such as bicarbonate, Met-L-X®, or inert smothering agents such as sand or graphite should be used to extinguish fires involving trialkylaluminum compounds.
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Reactivity and Incompatibility
Trialkylaluminum reagents are highly reactive reducing and alkylating agents. They react violently with air, water, alcohols, halogenated hydrocarbons, and oxidizing agents. These reagents are often supplied as solutions in hydrocarbon solvents, which are less hazardous than the pure liquids.
Storage and Handling
Trialkylaluminum agents should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented by the additional precautions for work with highly flammable (Chapter 5.F) and reactive (Chapter 5.G) substances. Safety glasses, impermeable gloves, and a fire-retardant laboratory coat should be worn at all times when working with these compounds. Trialkylaluminum reagents should be handled only under an inert atmosphere.
Accidents
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If trialkylaluminum compounds are ingested, obtain medical attention immediately. If any of these compounds are inhaled, move the person to fresh air and seek medical attention at once.
Any spill of trialkylaluminum will likely result in fire. Remove all ignition sources, put out the trialkylaluminum fire with a dry chemical extinguisher, sweep up the resulting solid, place in an appropriate container under an inert atmosphere, and dispose of properly. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Excess trialkylaluminum reagents and waste material containing these substances should be placed in an appropriate container under an inert atmosphere, clearly labeled, and handled according to your institution's waste disposal guidelines. Alternately, small quantities of trialkylaluminum reagents can be destroyed in the laboratory by experienced personnel by slow addition of t-butanol to a solution of the reagent in an inert solvent such as toluene under an inert atmosphere such as argon. The resulting mixture should then be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
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LABORATORY CHEMICAL INFORMATION SUMMARY: TRIMETHYLTIN CHLORIDE
(AND OTHER ORGANOTIN COMPOUNDS)
Substance
Trimethyltin chloride
(chlorotrimethylstannane)
CAS 1066-45-1
Other organotin compounds: tributyltin chloride, tributyltin hydride
Formula
C3H9ClSn
Physical Properties
White crystalline solid
mp 37 to 39 °C
Insoluble in water
Odor
Strong unpleasant stench; no threshold data available
Flash Point
97 °C
Toxicity Data
LD50 oral (rat)
12.6 mg/kg
PEL (OSHA)
0.1 mg tin/m3
The ACGIH has established the following uniform exposure limits for all organotin compounds based on the concentration of tin in air:
TLV-TWA (ACGIH)
0.1 mg tin/m3
STEL (ACGIH)
0.2 mg tin/m3
Major Hazards
Trimethyltin chloride is highly toxic by all routes of exposure.
Toxicity
Trimethyltin chloride and other organotin compounds are highly toxic by ingestion, inhalation, or skin contact. Trimethyltin chloride can cause irritation and burns of the skin and eyes. Organotin compounds can affect the central nervous system. The degree of toxicity is greatest for compounds with three or four alkyl groups attached to tin. Diand monoalkyltin compounds are moderately toxic. The toxicity diminishes as the size of the alkyl groups increases. Thus, the oral LD50s in rats are as follows: dimethyltin dichloride, 74 to 237 mg/kg; tributyltin chloride, 122 to 349 mg/kg; dibutyltin oxide, 487 to 520 mg/kg; trioctyltin chloride, >4000 mg/kg.
Organotin compounds have been shown to cause reproductive effects in laboratory animals.
Flammability and Explosibility
Not a significant fire hazard. Emits toxic fumes in fire.
Reactivity and Incompatibility
Trimethyltin chloride and other organotin halides react with water to produce hydrogen halides. Organotin hydrides react with water to produce hydrogen gas, which is flammable and explosive.
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Storage and Handling
Because of its high acute toxicity, trimethyltin chloride should be handled using the "basic prudent practices" of Chapter 5.C, supplemented by additional precautions for work with compounds of high acute toxicity (Chapter 5.D). Other alkyltin compounds should be handled using the "basic prudent practices" of Chapter 5.C.
Accidents
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If trimethyltin chloride or another organotin compound is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.
In the event of a spill, sweep up the organotin compound or soak up with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Respiratory protection may be necessary in the event of a large spill or release in a confined area.
Disposal
Excess trimethyltin chloride or other organotin compound and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines. For more information on disposal procedures, see Chapter 7 of this volume.
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