1,1,1-trichloroethane

H332: Harmful if inhaled [Warning Acute toxicity, inhalation]

H420: Harms public health and the environment by destroying ozone in the upper atmosphere [Warning Hazardous to the ozone layer]

P261, P271, P304+P340, P317, and P502 (click each P-code to see the statement)

H225 (31.1%): Highly Flammable liquid and vapor [Danger Flammable liquids]

H315 (23.3%): Causes skin irritation [Warning Skin corrosion/irritation]

H319 (47.7%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H332 (100%): Harmful if inhaled [Warning Acute toxicity, inhalation]

H420 (61.1%): Harms public health and the environment by destroying ozone in the upper atmosphere [Warning Hazardous to the ozone layer]

P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P271, P280, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P317, P321, P332+P317, P337+P317, P362+P364, P370+P378, P403+P235, P501, and P502 (click each P-code to see the statement)

Aggregated GHS information provided per 193 reports by companies from 14 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

H290: May be corrosive to metals [Warning Corrosive to Metals]

H315: Causes skin irritation [Warning Skin corrosion/irritation]

H320: Causes eye irritation [Warning Serious eye damage/eye irritation]

H336: May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects]

H350: May cause cancer [Danger Carcinogenicity]

H360: May damage fertility or the unborn child [Danger Reproductive toxicity]

H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure]

H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

H400: Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

H410: Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]

P203, P234, P260, P261, P264, P264+P265, P270, P271, P273, P280, P302+P352, P304+P340, P305+P351+P338, P308+P316, P317, P318, P319, P321, P332+P317, P337+P317, P362+P364, P390, P391, P403+P233, P405, P406, P501, and P502 (click each P-code to see the statement)

P203, P280, P318, P405, and P501 (click each P-code to see the statement)

P273, P391, P501, and P502 (click each P-code to see the statement)

H319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

H351: Suspected of causing cancer [Warning Carcinogenicity]

H361: Suspected of damaging fertility or the unborn child [Warning Reproductive toxicity]

H373: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure]

P203, P260, P261, P264, P264+P265, P270, P271, P280, P302+P352, P304+P340, P305+P351+P338, P308+P316, P318, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement)

Fresh air, rest. Artificial respiration may be needed. Refer for medical attention.

Remove contaminated clothes. Rinse and then wash skin with water and soap.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Do NOT induce vomiting. Rinse mouth. Give a slurry of activated charcoal in water to drink. Refer for medical attention .

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: DO NOT INDUCE VOMITING. Volatile chemicals have a high risk of being aspirated into the victim's lungs during vomiting which increases the medical problems. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. IMMEDIATELY transport the victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

General First Aid:

· Call 911 or emergency medical service.

· Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.

· Move victim to fresh air if it can be done safely.

· Administer oxygen if breathing is difficult.

· If victim is not breathing:

-- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.

-- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).

-- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.

· Remove and isolate contaminated clothing and shoes.

· For minor skin contact, avoid spreading material on unaffected skin.

· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.

· For severe burns, immediate medical attention is required.

· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

· Keep victim calm and warm.

· Keep victim under observation.

· For further assistance, contact your local Poison Control Center.

· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.

Specific First Aid:

· Wash skin with soap and water.

(General first aid procedures)

Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: Soap wash promptly - If this chemical contacts the skin, promptly wash the contaminated skin with soap and water. If this chemical penetrates the clothing, promptly remove the clothing and wash the skin with soap and water. Get medical attention promptly.

Breathing: Respiratory support

Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.

Excerpt from ERG Guide 160 [Halogenated Solvents]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Dry chemical, CO2, alcohol-resistant foam or water spray. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. (ERG, 2024)

In case of fire in the surroundings, use appropriate extinguishing media. In case of fire: keep drums, etc., cool by spraying with water.

DRY CHEMICAL, FOAM, OR CARBON DIOXIDE

If material involved in fire: Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Extinguish fire using agent suitable for type of surrounding fire (Material itself does not burn or burns with difficulty.). Keep run-off water out of sewers and water sources.

Extinguish fire using agent suitable for surrounding fire. Use water spray to keep fire-exposed containers cool. Approach fire from upwind to avoid hazardous vapors and toxic decomposition products.

Vapors are heavier than air and will collect in low areas. Storage containers and parts of containers may rocket great distances, in many directions.

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· Keep unauthorized personnel away.

· Stay upwind, uphill and/or upstream.

· Many gases are heavier than air and will spread along the ground and collect in low or confined areas (sewers, basements, tanks, etc.).

· Ventilate closed spaces before entering, but only if properly trained and equipped.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

· Stop leak if you can do it without risk.

Small Liquid Spill

· Pick up with sand, earth or other non-combustible absorbent material.

Large Spill

· Dike far ahead of liquid spill for later disposal.

· Prevent entry into waterways, sewers, basements or confined areas.

Excerpt from ERG Guide 160 [Halogenated Solvents]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 100 meters (330 feet).

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)

Immediate precautionary measure

· Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

· Consider initial downwind evacuation for at least 100 meters (330 feet).

· If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.

Personal protection: self-contained breathing apparatus. Ventilation. Do NOT let this chemical enter the environment. Collect leaking liquid in sealable containers. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.

Environmental considerations: land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash, cement powder, or commmercial sorbents.

Environmental considerations: water spill: Use natural barriers or oil spill control booms to limit spill travel. Use natural deep water pockets, excavated lagoons, or sand bag barriers to trap material at bottom. Remove trapped material with suction hoses.

Absorb on paper and evaporate on a glass dish in hood. Burn the paper.

The ability of different aerobic groundwater microorganisms to cometabolically degrade trichloroethylene (TCE), 1,2-cis-dichloroethylene (c-DCE) and 1,2-trans-dichloroethylene (t-DCE) was evaluated both in groundwater fed microcosms and in situ in a shallow aquifer. Microcosms amended with phenol or toluene were equally effective in removing c-DCE (> 90%) followed by TCE (60 to 70%), while the microcosm fed methane was most effective in removing t-DCE (>-90%). The microcosm fed ammonia was the least effective. None of the microcosms effectively degraded l,l,l-trichloroethane. At the Moffett Field groundwater test site, in situ removal of c-DCE and TCE coincided with biostimulation through phenol and oxygen injection and utilization with c-DCE removed more rapidly than TCE. Greater TCE and c-DCE removal was observed when the phenol concentration was increased. Over 90% removal of c-DCE and TCE was observed in the 2 m biostimulated zone. This compares with 40 to 50 removal of c-DCE and 15 to 25% removal of TCE achieved by methane grown microorganisms previously evaluated in an adjacent in situ test zone. The in situ removal with phenol grown microorganisms agrees quantitatively with the microcosm studies with the rates and extends of removal ranked as follows: c-DCE > TCE > t-DCE. These studies demonstrate potential for in situ TCE bioremediation using microorganisms grown on phenol.

Use appropriate foam to blanket release and suppress vapors. Absorb in noncombustible material for proper disposal. Report any release in excess of 1 lb.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste numbers U226 and F002, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Trichloroethane is a waste chemical stream constituent which may be subjected to ultimate disposal by controlled incineration. Incineration, preferably after mixing with another combustible fuel; care must be exercised to assure complete combustion to prevent the formation of phosgene. An acid scrubber is necessary to remove the halo acids produced. /Trichloroethane/

A potential candidate for liquid injection incineration at a temperature range of 650 to 1,600 °C and a residence time of 0.1 to 2 seconds. A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids. A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids.

Chemical Treatability of 1,1,1-Trichloroethane; Concentration Process: Biological treatment; Chemical Classification: Halocarbon; Scale of Study: Full scale, continuous flow; Type of Wastewater Used: Industrial waste; Results of Study: Effluent concentration; 1.0-20.0 ppb (Survey of 2 municipal wastewater treatment plants).

For more Disposal Methods (Complete) data for 1,1,1-TRICHLOROETHANE (14 total), please visit the HSDB record page.

SRP: The scientific literature for the use of contact lenses by industrial workers is inconsistent. The benefits or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

SRP: Contaminated protective clothing should be segregated in a manner such that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. The completeness of the cleaning procedures should be considered before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at the end of shift, but should remain at employee's place of work for cleaning.

The worker should immediately wash the skin when it becomes contaminated.

Work clothing that becomes wet or significantly contaminated should be removed and replaced.

For more Preventive Measures (Complete) data for 1,1,1-TRICHLOROETHANE (6 total), please visit the HSDB record page.

Excerpt from ERG Guide 160 [Halogenated Solvents]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. Stop leak if you can do it without risk.

SMALL LIQUID SPILL: Pick up with sand, earth or other non-combustible absorbent material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2024)

Separated from food and feedstuffs, strong oxidants, aluminium, magnesium and zinc. Cool. Dry. Store in an area without drain or sewer access.

Storage temp: Ambient; Venting: Pressure-vacuum.

Protection from moisture be provided for bulk storage, and do not store in aluminum containers.

Store in a cool, dry, well-ventilated location. Separate from oxidizing materials, ammonia, and active metals, such as aluminum.

Before being stored or transported over longer periods of time, chlorinated ethanes ... should be carefully analyzed for water, free acid, and stabilizers because decomposition may lead to excessive corrosion. ... Chlorinated ethanes should not be brought into contact with tanks, containers, valves, etc made of aluminum. /Chloroethanes/

For more Storage Conditions (Complete) data for 1,1,1-TRICHLOROETHANE (6 total), please visit the HSDB record page.

· Wear positive pressure self-contained breathing apparatus (SCBA).

· Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE.

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

Biological Exposure Indices (BEI) [ACGIH] - Methyl chloroform in end-exhaled air = 40 ppm prior to last shift of workweek; for trichloroethanol in blood and urine and TCA in urine BEIs, see the ACGIH booklet;

100.0 [ppm]

AEGL 1: Notable discomfort, irritation, or certain asymptomatic non-sensory effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure (Unit: ppm)

AEGL 2: Irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape (Unit: ppm)

AEGL 3: Life-threatening health effects or death (Unit: ppm)

NR = Not recommended due to insufficient data

AEGLs Status: Interim

230 [ppm]

600 [ppm]

4200 [ppm]

350 ppm (1900 mg/m³) [15 minutes]

C 350 ppm (1900 mg/m3) [15-minute] See Appendix C (Chloroethanes)

350.0 [ppm]

350 ppm (1900 mg/m³)

TWA 350 ppm (1900 mg/m3) See Appendix G

700 ppm (NIOSH, 2024)

700.0 [ppm]

Excerpts from Documentation for IDLHs: Other animal data: No significant signs of intoxication were seen in rats inhaling 500 ppm, 6 hours per day for 4 days [Savolainen et al. 1977]; in mice inhaling up to 1,300 ppm for 1 hour [Kjellstrand et al. 1985]; in rats inhaling up to 3,000 ppm for 0.5 to 4 hours [Mullin and Krivanek 1982]; or in baboons inhaling up to 1,400 ppm for 4 hours [Geller et al. 1982]. \\ Human data: The onset of central anesthesia has occurred in individuals exposed for up to 7 hours to concentrations approaching 500 ppm [Stewart et al. 1969]. It has been stated that exposure to 900 to 1,000 ppm causes prompt, though minimal impairment of coordination; obvious disturbances in equilibrium have been noted above 1,700 ppm [MCA 1965]. Those exposed to 800 to 1,000 ppm have exhibited early anesthetic effects including incoordination [Stewart et al. 1961]. Volunteers exposed to 920 ppm for 5 to 45 minutes showed a slight loss of coordination and equilibrium [Stewart et al. 1961].

See: 71556

450.0 [ppm]

8 hr Time Weighted Avg (TWA): 350 ppm; Short Term Exposure Limit (STEL): 450 ppm.

A4; Not classifiable as a human carcinogen.

Biological Exposure Index (BEI): Determinant: methyl chloroform in end-exhaled air; Sampling Time: prior to last shift of workweek; BEI: 40 ppm.

Biological Exposure Index (BEI): Determinant: trichloroacetic acid in urine; Sampling Time: end of workweek; BEI: 10 mg/L. Notations: The determinant is nonspecific, since it is also observed after exposure to other chemicals.; The biological determinant is an indicator of exposure to the chemical, but the quantitative interpretation of the measurement is ambiguous. These determinants should be used as a screening test if a quantitative test is not practical, or as a confirmatory test if the quantitative test is not specific and the origin of the determinant is in question.

For more Threshold Limit Values (TLV) (Complete) data for 1,1,1-TRICHLOROETHANE (6 total), please visit the HSDB record page.

350 ppm as TWA; 450 ppm as STEL; A4 (not classifiable as a human carcinogen); BEI issued.

350 ppm [1992]

450 ppm [1992]

555 mg/m

550 mg/m

Acute Inhalation: 2 ppm (L304)

Intermediate Inhalation: 0.7 ppm (Gerbil) (L304)

Intermediate Oral: 20 mg/kg/day (Mouse) (L304)

Small Fire

· Dry chemical, CO2 or water spray.

Large Fire

· Dry chemical, CO2, alcohol-resistant foam or water spray.

· If it can be done safely, move undamaged containers away from the area around the fire.

· Dike runoff from fire control for later disposal.

1,1,1-trichloroethane appears as a colorless liquid with a sweet, pleasant odor. May irritate skin, eyes and mucous membranes. In high concentrations the vapors may have a narcotic effect. Nonflammable, but may decompose and emit toxic chloride fumes if exposed to high temperatures. Used as a solvent.

Colorless liquid with a mild, chloroform-like odor; [NIOSH] Clear colorless liquid with a sweet odor; [Matheson Tri-Gas MSDS]

COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR.

Colorless liquid with a sweet, chloroform-like odor.

Colorless liquid with a mild, chloroform-like odor.

Colorless liquid

Clear liquid at ambient temperature

... Mild chloroform-like odor

Sweetish

Characteristic ethereal odor

165.4 °F at 760 mmHg (NTP, 1992)

74.00 °C. @ 760.00 mm Hg

74.09 °C @760 [mm Hg]

-26.5 °F (NTP, 1992)

-30.4 °C

-26.5 °F

-30.01 °C

greater than 200 °F (NTP, 1992)

Flash point = none

less than 1 mg/mL at 68 °F (NTP, 1992)

In water, 1,290 mg/L at 25 °C

Soluble in acetone, benzene, methanol, carbon tetrachloride and ether

Soluble in all common organic solvents and is a very good solvent for fats, paraffins, and other organic compounds.

1.29 mg/mL at 25 °C

Solubility in water: poor

1.31 at 68 °F (USCG, 1999) - Denser than water; will sink

1.3376 at 20 °C/4 °C

Chlorothene VG Solvent: Freezing Point -36.9 °C; Boiling range at 760 mm Hg 72-88 °C; Density 1.232 g/mL at 20 °C; Specific gravity 1.327 at 20 °C/20 °C, 1.333 at 60 °C/60 °C, 1.320 at 25 °C/25 °C; Heat of vaporization 7.8 kcal/mol at 20 °C, 7.5 kcal/mol at 50 °C, 7.1 kcal/mol at 80 °C (calculated); Dielectric constant at 24 °C 10.0 at 10+3 cps, 7.0 at 10+5 cps

Relative density (water = 1): 1.34

1.3390 @ 20°C

4.6 (NTP, 1992) - Heavier than air; will sink (Relative to Air)

4.63 (Air = 1)

Relative vapor density (air = 1): 4.6

100 mmHg at 68 °F ; 125 mmHg at 77 °F (NTP, 1992)

124.0 [mmHg]

124 mm Hg at 25 °C

Vapor pressure, kPa at 20 °C: 13.3

100 mmHg

75 [mm Hg] @14.2 °C

log Kow = 2.49

Insoluble in water. Absorbs some water.

Halogenated Organic Compounds

1,1,1-TRICHLOROETHANE decomposes in the presence of chemically active metals. This includes aluminum, magnesium and their alloys. It will react violently with dinitrogen tetraoxide, oxygen, liquid oxygen, sodium and sodium-potassium alloys. It will also react violently with acetone, zinc and nitrates. It can react with sodium hydroxide. It is incompatible with strong oxidizers and strong bases. Mixtures with potassium or its alloys are shock-sensitive and may explode on light impact. This chemical can react with an aqueous suspension of calcium hydroxide, and with chlorine in sunlight. It will attack some forms of plastics, rubber and coatings. Upon contact with hot metal or on exposure to ultraviolet radiation, it will decompose to form irritant gases. A cobalt/molybdenum-alumina catalyst will generate a substantial exotherm on contact with its vapor at ambient temperatures. Hazardous reactions also occur with (aluminum oxide + heavy metals). (NTP, 1992).

Reacts slowly with water, releasing corrosive hydrochloric acid.

Although apparently stable on contact, mixtures with potassium (or its alloys) with a wide range of halocarbons /including trichloroethane/ are shock-sensitive and may explode with great violence on light impact. ...

Violent decomp, with evolution of hydrogen chloride, may occur when /it/ ... comes into contact with aluminum or its alloys with magnesium.

A pipe- and solenoid-valve assembly used to transfer /sodium-potassium alloy/ had been purged with nitrogen, then flushed with water. Trichloroethane, used subsequently to remove traces of water, contacted hidden residue of /sodium-potassium alloy/ in one valve and an explosion ensued.

For more Hazardous Reactivities and Incompatibilities (Complete) data for 1,1,1-TRICHLOROETHANE (10 total), please visit the HSDB record page.

Strong caustics; strong oxidizers; chemically-active metals such as zinc, aluminum, magnesium powders, sodium & potassium; water [Note: Reacts slowly with water to form hydrochloric acid.]

CDC-ATSDR Toxicological Profile

Safe in the present practices of use and concentration. Ingredient, concentration, and use information are available in documents discoverable at https://cir-reports.cir-safety.org

IDENTIFICATION AND USE: 1,1,1-Trichloroethane is a colorless liquid with a mild sweet odor. It is used as a cleaning solvent, as a chemical intermediate to produce vinylidene chloride, and as a propellant in aerosol cans. The EPA lists it as an inert pesticide ingredient, approved for nonfood use only. HUMAN EXPOSURE AND TOXICITY: The findings in human volunteers indicate that the urinary concentration of 1,1,1-trichloroethane can be used as an appropriate biological exposure indicator. Neurological response effects have been shown in acute exposure studies at 900 to 1000 ppm were reduced coordination, and inhalation of 1700 ppm or repeated inhalation of 500 ppm over 5 days reduced Romberg's test performance. Inhalation of very high 1,1,1-trichloroethane concentrations for a short period can produce severe cardiac arrhythmias and death in humans. Arrhythmias are thought to be produced indirectly by 1,1,1-trichloroethane by sensitization of the heart to epinephrine. In addition, reduced blood pressure, occasionally severe, has been reported in humans following brief exposure to high concentrations. Early symptoms may include mild eye and nasal discomfort and impairment of equilibrium and coordination. Increased lassitude and headache occur with heavier exposures and in severe poisoning progressive CNS depression occurs. Hepatotoxicity may not become manifest until near-anesthetic levels are reached. Nausea is apparently not common. Several deaths have occurred following industrial exposure in confined spaces and also in the context of solvent abuse. A 44 year old female with complaints of apparent work related perioral tingling and burning, and hand and foot discomfort was evaluated. After she was removed from work, the oral and hand symptoms disappeared, but she was left with sensations of burning and cramping in her feet which made it difficult to walk or stand for prolonged periods of time. Physical examination revealed decreased vibration sensitivity in both big toes. She had normal tendon reflexes, no evidence of muscle atrophy or weakness was seen. Testing of evoked potential, electromyographic, and motor nerve conduction velocity yielded normal results. The sensory nerve conduction velocity testing revealed, reduced amplitudes of sural sensory responses bilaterally and normal conduction velocities. This was diagnostic of a toxic axonopathy. The patient reported that she had been employed for the past 18 months as a hydraulic pump dismantler and parts cleaner. She typically spent half of her workday using a degreasing agent that was essentially 1,1,1-trichloroethane. She used protective gloves and a respirator, but she reported that they frequently leaked. She was permanently removed from work. Within 6 months, her symptoms had almost completely disappeared. Repeat sensory nerve conductance testing indicated a 32% improvement in the response. ANIMAL STUDIES: Rats were less affected by the solvents when they were tested in highly motivating situations, for example, rewarded for rapid or correct responding or escape from electrical shock, compared with less motivating circumstances. When tested in tasks with low-motivational contingencies, the dose-effect curves of humans (reaction times) and rats (electrophysiological responses to visual stimuli) were not significantly different. However, on an exploratory follow-up analysis, humans were less sensitive than rats. Dose-equivalence curves were derived for extrapolating to human effects from rat data. Carcinogenicity of 1,1,1-trichloroethane was examined by an inhalation exposure of rats and mice of both sexes at 0, 200, 800 or 3200 ppm for 6 hr/d, 5 d/week for 104 weeks. In male rats, the incidences of bronchiolo-alveolar adenomas and peritoneal mesotheliomas were significantly increased in the 800 and 3200 ppm-exposed groups, respectively. In female rats, the tumor incidences were not increased in any organs. 1,1,1-Trichloroethane did not induce unscheduled DNA synthesis in rat primary hepatocytes. It showed inconclusive evidence of gene mutation at the tk locus in mouse lymphoma L5178Y cells in the presence of an exogenous metabolic activation system. Results for induction of sister chromatid exchanges were also inconclusive. 1,1,1-Trichloroethane increased the frequency of chromosomal aberrations in Chinese hamster ovary cell cultures and induced morphological transformation in rat and virally-enhanced Syrian hamster embryo cells in vitro. 1,1,1-Trichloroethane did induce mutations in S. typhimurium strains TA100 and TA1535 in the presence or absence of exogenous metabolic activation. It induced reverse mutations in Escherichia coli in the presence of exogenous metabolic activation in one of three studies. It did not induce DNA damage, gene conversion, mutation or aneuploidy in Saccharomyces cerevisiae. It did not induce genetic crossing-over or aneuploidy in Aspergillus nidulans, mutation in Tradescantia or sex-linked recessive lethal mutation in Drosophila melanogaster. ECOTOXICITY STUDIES: 1,1,1-Trichloroethane was tested in aquatic species and plants without significant toxic effects.

1,1,1-Trichloroethane is a cholinesterase or acetylcholinesterase (AChE) inhibitor. A cholinesterase inhibitor (or 'anticholinesterase') suppresses the action of acetylcholinesterase. Because of its essential function, chemicals that interfere with the action of acetylcholinesterase are potent neurotoxins, causing excessive salivation and eye-watering in low doses, followed by muscle spasms and ultimately death. Nerve gases and many substances used in insecticides have been shown to act by binding a serine in the active site of acetylcholine esterase, inhibiting the enzyme completely. Acetylcholine esterase breaks down the neurotransmitter acetylcholine, which is released at nerve and muscle junctions, in order to allow the muscle or organ to relax. The result of acetylcholine esterase inhibition is that acetylcholine builds up and continues to act so that any nerve impulses are continually transmitted and muscle contractions do not stop. Among the most common acetylcholinesterase inhibitors are phosphorus-based compounds, which are designed to bind to the active site of the enzyme. The structural requirements are a phosphorus atom bearing two lipophilic groups, a leaving group (such as a halide or thiocyanate), and a terminal oxygen.

1,1,1-Trichloroethane

2 mg/kg-day

7 mg/kg-day

5 mg/m^3

Volatile Organic Compound (VOC) (Pesticide/Volatile Organic Compound (VOC))

Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

Cancer Classification: Group D Not Classifiable as to Human Carcinogenicity

Evaluation: There is inadequate evidence for the carcinogenicity of 1,1,1-trichloroethane in humans. There is inadequate evidence for the carcinogenicity of 1,1,1-trichloroethane in experimental animals. Overall evaluation: 1,1,1-Trichloroethane is not classifiable as to its carcinogenicity to humans (Group 3).

A4; Not classifiable as a human carcinogen.

Group 2A: Probably carcinogenic to humans

Volume 20: (1979) Some Halogenated Hydrocarbons

Volume Sup 7: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1 to 42, 1987; 440 pages; ISBN 92-832-1411-0 (out of print)

Volume 71: (1999) Re-evaluation of Some Organic Chemicals, Hydrazine and Hydrogen Peroxide (Part 1, Part 2, Part 3)

Volume 130: (2022) 1,1,1-Trichloroethane and Four Other Industrial Chemicals

2022 online

TR-003: Bioassay of 1,1,1-Trichloroethane for Possible Carcinogenicity (CASRN 71-55-6) (1977 )

Inadequate Experiment

3, not classifiable as to its carcinogenicity to humans. (L310)

Acute exposure to cholinesterase inhibitors can cause a cholinergic crisis characterized by severe nausea/vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. Accumulation of ACh at motor nerves causes overstimulation of nicotinic expression at the neuromuscular junction. When this occurs symptoms such as muscle weakness, fatigue, muscle cramps, fasciculation, and paralysis can be seen. When there is an accumulation of ACh at autonomic ganglia this causes overstimulation of nicotinic expression in the sympathetic system. Symptoms associated with this are hypertension, and hypoglycemia. Overstimulation of nicotinic acetylcholine receptors in the central nervous system, due to accumulation of ACh, results in anxiety, headache, convulsions, ataxia, depression of respiration and circulation, tremor, general weakness, and potentially coma. When there is expression of muscarinic overstimulation due to excess acetylcholine at muscarinic acetylcholine receptors symptoms of visual disturbances, tightness in chest, wheezing due to bronchoconstriction, increased bronchial secretions, increased salivation, lacrimation, sweating, peristalsis, and urination can occur. Certain reproductive effects in fertility, growth, and development for males and females have been linked specifically to organophosphate pesticide exposure. Most of the research on reproductive effects has been conducted on farmers working with pesticides and insecticdes in rural areas. In females menstrual cycle disturbances, longer pregnancies, spontaneous abortions, stillbirths, and some developmental effects in offspring have been linked to organophosphate pesticide exposure. Prenatal exposure has been linked to impaired fetal growth and development. Neurotoxic effects have also been linked to poisoning with OP pesticides causing four neurotoxic effects in humans: cholinergic syndrome, intermediate syndrome, organophosphate-induced delayed polyneuropathy (OPIDP), and chronic organophosphate-induced neuropsychiatric disorder (COPIND). These syndromes result after acute and chronic exposure to OP pesticides.

The substance can be absorbed into the body by inhalation of its vapour and by ingestion.

inhalation, ingestion, skin and/or eye contact

Oral (L306); inhalation (L306) ; dermal (L306)

Cough. Sore throat. Headache. Dizziness. Drowsiness. Nausea. Incoordination. Unconsciousness.

Dry skin. Redness.

Redness. Pain.

Nausea. Vomiting. Abdominal pain. Diarrhoea. Further see Inhalation.

irritation eyes, skin; headache, lassitude (weakness, exhaustion), central nervous system depression, poor equilibrium; dermatitis; cardiac arrhythmias; liver damage

Symptoms include cough, sore throat, headache, dizziness, drowsiness, nausea, ataxia, unconsciousness. Dry skin and redness follow dermal exposure, while nausea, vomiting, abdominal pain, and diarrhoea follw ingestion. (L306)

Body Weight, Hepatic (Liver), Neurological (Nervous System)

Eyes, skin, central nervous system, cardiovascular system, liver

Neurotoxin - Acute solvent syndrome

Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.

IARC Carcinogen - Class 2: International Agency for Research on Cancer classifies chemicals as probable (2a), or possible (2b) human carcinogens.

ACGIH Carcinogen - Not Classifiable.

IRIS Current

ATSDR Final

LD50; Species: Colinus virginianus (Northern bobwhite) age 22 weeks; oral >2510 mg/kg for 14 days

LC50; Species: Colinus virginianus (Northern bobwhite) age 14 days; diet >5620 ppm for 8 days

LC50; Species: Anas platyrhynchos (Mallard duck) age 14 days; diet >5620 ppm for 8 days

LC50; Species: Eisenia fetida (Earthworm) adult, weight 300-500 mg; dermal 83 ug/sq cm for 48 hr (76-91 ug/sq cm)

For more Ecotoxicity Values (Complete) data for 1,1,1-TRICHLOROETHANE (35 total), please visit the HSDB record page.

/AQUATIC SPECIES/ When ...the water flea Daphnia magna /was exposed/ to 1,1,1-trichloroethane concentrations of between 1.3 and 23 mg/L for 17 days under semistatic conditions (water renewed every 2 days), no effect on mortality or reproduction (as measured by number of offspring per parent) was observed at 1.3 mg/L. However, the mortality increased with increasing concentration of 1,1,1-trichloroethane from 30% at 2.4 mg/L to 100% at 23 mg/L. The number of offspring per parent was significantly reduced at concentrations of 2.4 mg/L or more.

/AQUATIC SPECIES/ The toxicity of 1,1,1-trichloroethane to carp (Cyprinus carpio) and daphnids (Daphnia magna)... was investigated. The test systems were designed to minimize loss of the volatile material during the exposure period. During an exposure period of 14 days, there were no mortalities or other symptoms of toxicity in carp exposed to a mean measured 1,1,1-trichloroethane concentration of 7.7 mg/L. The survival and reproduction of daphnids over a test period of 17 days were not affected at a measured concentration of 1.3 mg/L. ...The simple modifications made to standard techniques proved sufficient to maintain the exposure concentrations of this volatile chemical. Mean measured concentrations were generally greater than 60% of the nominal values.

/PLANTS/ ...The effects of gaseous-phase exposure /to 1,1,1-trichloroethane on the growth of higher plants (sorghum bicolor and brassica napus) were investigated. The test systems were designed to minimize loss of the volatile material during the exposure period. ...Growth of emergent seedlings was not inhibited at measured gaseous-phase concentrations of 18 mg/L for S. bicolor and 6.9 mg/L for B. napus. The simple modifications made to standard techniques proved sufficient to maintain the exposure concentrations of this volatile chemical. Mean measured concentrations were generally greater than 60% of the nominal values.

/PLANTS/ Effects of a series of chlorinated ethenes and ethanes on hybrid poplar (Populus deltoides x nigra DN34) were assessed in laboratory experiments. Poplar cuttings were grown in sealed reactors with hydroponic solutions and were exposed to a chlorinated solvent for a period of two weeks. Exposure concentrations ranged from 0 to 0.4 mM for perchloroethylene to 0 to 8.4 mM for 1,1-dichloroethane. Effects were assessed by gravimetrically monitoring transpiration and measuring change in cutting mass. The zero-growth concentrations of the chemicals tested were 0.3 mM perchloroethylene, 0.9 mM trichloroethylene, 0.9 mM 1,1,2,2-tetrachloroethane, 2.0 mM 1,1,1-trichloroethane, 2.3 mM 1,1,2-trichloroethane, 4.8 mM trans-dichloroethylene, 5.6 mM 1,1-dichloroethylene, 6.0 mM cis-dichloroethylene, and 10.7 mM 1,1-dichloroethane. Adverse effects were found to increase with increasing number of chlorine atoms within a homologous series of ethenes or ethanes. Ethenes were more toxic than similarly chlorinated ethanes.

8.10e+03

3.60e+04

5.20e+03

2.20e+04

8.00e+03

2.00e+02

2.80e+00

7.00e-02

2.00e+00

5.00e+00

Volatile

6.40e+02

2.40e+04

1.10e+05

1.60e+04

6.60e+04

The substance is harmful to aquatic organisms.

1,1,1-Trichloroethane's production and current use as feedstock for fluorocarbons, such as HFC-134a and HCFC-142b, which in turn are used as feedstock to produce fluoropolymers, such as poly(vinylidene fluoride) may result in its release to the environment through various waste streams. Its former use as a solvent in numerous industrial applications such as cleaning and vapor degreasing and as a solvent in adhesives, coatings and inks resulted in its release to the environment through various waste streams. 1,1,1-Trichloroethane's current use as an approved inert ingredient in pesticides for nonfood uses will result in its direct release to the environment. If released to air, a vapor pressure of 124 mm Hg at 25 °C indicates 1,1,1-trichloroethane will exist solely as a vapor in the atmosphere. Vapor-phase 1,1,1-trichloroethane will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 4.6 years. 1,1,1-Trichloroethane does not absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight in the troposphere. Due to its long atmospheric lifetime, 1,1,1-trichloroethane will gradually diffuse into the stratosphere above the ozone layer where it will slowly degrade due to direct photolysis from UV-C radiation and contribute to the catalytic removal of stratospheric ozone. If released to soil, 1,1,1-trichloroethane is expected to have high mobility based upon Koc values of 66-151 measured in soil. Volatilization from moist soil surfaces is expected to be an important fate process based upon a Henry's Law constant of 0.0163 atm-cu m/mole. 1,1,1-Trichloroethane is expected to volatilize from dry soil surfaces based upon its vapor pressure. 1,1,1-Trichloroethane is expected to biodegrade slowly in soil. It is not expected to undergo aerobic biodegradation in soil, but there are some experimental data that indicate biodegradation may occur under anaerobic conditions. Aerobic half-lives of >97 days and >485 days were measured in two non-adapted soils from Louisiana and Oklahoma, respectively. If released into water, 1,1,1-trichloroethane is not expected to adsorb to suspended solids and sediment based upon the Koc range. Slow biodegradation may occur in water under anaerobic or aerated conditions; degradation may take weeks and acclimation is important. A half-life of 9 months was observed in seawater. Volatilization from water surfaces is expected to be an important fate process based upon this compound's Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 3.4 hours and 4.6 days, respectively. BCF values of 0.7 to 8.9 measured in fish, suggest bioconcentration in aquatic organisms is low. The hydrolysis half-life of 1,1,1-trichloroethane is 1.1 years in distilled water at 25 °C. Occupational exposure to 1,1,1-trichloroethane may occur through inhalation and dermal contact with this compound at workplaces where 1,1,1-trichloroethane produced or used. Monitoring data indicate that the general population may be exposed to 1,1,1-trichloroethane through inhalation of ambient air and ingestion of contaminated drinking water and food. (SRC)

1,1,1-Trichloroethane's production and current use as feedstock for fluorocarbons, such as HFC-134a and HCFC-142b, which in turn are used as feedstock to produce fluoropolymers, such as poly(vinylidene fluoride)(1) may result in its release to the environment through various waste streams(SRC). Its former use as a solvent in numerous industrial applications such as cleaning and vapor degreasing(1) and as a solvent in adhesives, coatings and inks(2) resulted in its release to the environment through various waste streams(2). 1,1,1-Trichloroethane's current use as an approved inert ingredient in pesticides for nonfood uses(3) will result in its direct release to the environment(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values of 66-151 measured in soil(2,3), indicate that 1,1,1-trichloroethane is expected to have high mobility in soil(SRC). Volatilization of 1,1,1-trichloroethane from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 0.0163 atm-cu m/mole(4). 1,1,1-Trichloroethane is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 124 mm Hg(5). The biodegradation half-life of 1,1,1-trichloroethane in non-adapted aerobic soils from Louisiana and Oklahoma were reported as >97 days and >485 days, respectively(6), suggesting that biodegradation may not be an important fate process in soil(SRC). 1,1,1-Trichloroethane is not expected to undergo aerobic biodegradation in soil, but there are some experimental data that indicate biodegradation may occur under anaerobic conditions(7). An anaerobic microcosm study using mixed microbial cultures obtained from a contaminated site in the northeastern US found that 1,1,1-trichloroethane was reductively dechlorinated to 1,1-dichloroethane and then to monochloroethane(8).

AQUATIC FATE: Based on a classification scheme(1), Koc values of 66-151(2,3), indicate that 1,1,1-trichloroethane is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(4) based upon a Henry's Law constant of 0.0163 atm-cu m/mole(5). Using this Henry's Law constant and an estimation method(4), volatilization half-lives for a model river and model lake are 3.4 hours and 4.6 days, respectively(SRC). According to a classification scheme(6), BCF values of 0.7 to 8.9 measured in carp (Cyprinus carpio) and bluegill sunfish (Lepomis macrochirus)(7,8), suggest the potential for bioconcentration in aquatic organisms is low(SRC). Aerobic biodegradation of 1,1,1-trichloroethane is slow in water, but may occur in the presence of methane-oxidizing bacteria(9). Slow degradation may occur in water under anaerobic or aerated conditions; degradation may take weeks and acclimation is important(10,11). A half-life of 9 months was observed in seawater(12). The aqueous hydrolysis half-life of 1,1,1-trichloroethane has been experimentally determined to be 1.1 years at 25 °C(13).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1,1,1-trichloroethane , which has a vapor pressure of 124 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 1,1,1-trichloroethane is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 4.6 years(SRC), calculated from its rate constant of 9.50X10-15 cu cm/molecule-sec at 25 °C(3). The UV absorption spectrum of 1,1,1-trichloroethane from 160-255 nm(4) suggests that 1,1,1-trichloroethane will not absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC). 1,1,1-Trichloroethane has been detected in rainwater(5,6); therefore, it may be removed from the air by wet deposition(SRC). Due to its long atmospheric lifetime, 1,1,1-trichloroethane will gradually diffuse into the stratosphere above the ozone layer where it will slowly degrade due to direct photolysis from UV-C radiation and contribute to the catalytic removal of stratospheric ozone(7).

AEROBIC: No degradation was observed in subsurface soils in 27 weeks of incubation; however, in loamy sand, slow degradation was observed under acclimated conditions(1,2). Slow degradation may occur in water under anaerobic or aerated conditions; degradation may take several weeks and acclimation is important(3,4). In seawater, a half-life of 9 months has been determined and vinylidene chloride is the degradation product(5). No degradation in river water was found(6). No utilization of 1,1,1-trichloroethane occurred in a continuously-fed aerobic biofilm reactor that utilized acetate as its primary substrate; however, 98% removal was obtained in a similar anaerobic reactor with a 2-day retention time after 8 wk acclimation(8). 1,1,1-Trichloroethane degraded to vinylidene chloride as a first step in its biotransformation in microcosms containing aquifer water and sediment collected from uncontaminated sites in the Everglades(7); considerable degradation occurred within two weeks(7). Field evidence of biodegradation in aquifers was obtained by following the concentration of 1,1,1-trichloroethane in a confined aquifer after it was injected with reclaimed groundwater(8); the half-life of 1,1,1-trichloroethane was 231 days with biodegradation given as the probable cause of loss(8). The biodegradation half-life of 1,1,1-trichloroethane in non-adapted aerobic soils from Louisiana and Oklahoma were reported as >97 days and >485 days, respectively(9). 1,1,1-Trichloroethane at 100 mg/L achieved 0% of its theoretical BOD using an activated sludge inoculum at 30 mg/L over a 2 week incubation period in the Japanese MITI test(10).

ANAEROBIC: 1,1,1-Trichloroethane has been shown to undergo biotransformation under methanogenic conditions(1-3); the biotransformation proceeds by a reductive dechlorination to 1,1-dichloroethane and chloroethane(1). Laboratory reactors using mixed acclimated anaerobic microbial populations have demonstrated that 1,1,1-trichloroethane can be biodegraded under anaerobic simulations(4,5,6); it was suggested that in-situ anaerobic biodegrdation may be a viable alternative for clean-up for various contaminated soil and groundwater sites(5). 1,1,1-Trichloroethane biodegraded in anoxic biofilm columns with an effluent removal that exceeded 99% (at 10 ppb influent) after 9-12 wks of acclimation(7). The half-life of 1,1,1-trichloroethane in an unpolluted anaerobic aquifer was estimated as 9 days (1% organic carbon content), 32 days (0.1% organic carbon content), 346 days (0.01% organic carbon content) and 16 years (0.001% organic carbon content)(8). Anoxic laboratory experiments simulating conditions in water unsaturated topsoil observed that degradation of 1,1,1-trichloroethane was similar in biologically active batches as compared to sterile batches(9). An anaerobic microcosm study using mixed microbial cultures obtained from a contaminated groundwater site in the northeastern US found that 1,1,1-trichloroethane was reductively dechlorinated to 1,1-dichloroethane and then to monochloroethane(10).

The rate constant for the vapor-phase reaction of 1,1,1-trichloroethane with photochemically produced hydroxyl radicals has been experimentally determined to be 9.50X10-15 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 4.6 years at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(2). The neutral aqueous hydrolysis rate constants of 1,1,1-trichloroethane at 25 °C has been experimentally determined to be 1.24X10-6 per minute(2); the hydrolytic half-life at pH 7 is 1.1 yr(3). The basic hydrolysis rate constant is essentially zero(3). The aqueous hydrolysis half-life of 1,1,1-trichloroethane in water containing subsurface sediment at 25 °C was measured to be 450 days(4); this is not significantly different than in pure water(4). Hydrolysis half-lives of 6 months to 1 year have been determined in other laboratory studies at 25 °C(5). An hydrolysis half-life of 1.7 years was determined at 20 °C(5). The measured UV absorption spectrum of 1,1,1-trichloroethane from 160-255 nm(6) suggests that 1,1,1-trichloroethane will not absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC). Aqueous solutions of 1,1,1-trichloroethane exposed to sunlight for 12 months exhibited the same degradation rates as solutions not exposed to sunlight (degradation was due to hydrolysis)(5). A laboratory microcosm study examining the biotic degradation of 1,1,1-trichloroethane noted the occurrence of abiotic degradation that may have been mediated by biotic formation of FeS(7); it was suggested that this abiotic mechanism may be relevant at field sites(7). Laboratory findings suggest that iron-bearing minerals and methanogenic bacteria that co-occur in reduced aquifers may synergistically affect dechlorination of 1,1,1-trichloroethane(8).

A BCF range of 0.7 to 4.9 was measured using carp (Cyprinus carpio) which were exposed over an 6-week period(1). A BCF of 8.9 was determined in bluegill sunfish (Lepomis macrochirus) in a 28 day test(2). A BCF of 2.95 was measured in killfish (Oryzias latipes) over an 8-day exposure period(3). According to a classification scheme(4), these BCF values suggest that bioconcentration in aquatic organisms is low(SRC).

The adsorption of 1,1,1-trichloroethane was studied using three US soils(1); equilibrium adsorption coefficients (Kd) of 1.8, 1.592, and 1.338 were measured using a soil from Missouri (11.4% sand, 52.7% silt, 33.4% clay, 2.4% organic matter), California (45.1% sand, 35.2% silt, 21.7% clay, 1.7% organic matter) and Florida (9.17% sand, 6.3% silt, 2% clay, 1.6% organic matter), respectively(1); these adsorption coefficients correspond to Koc values of 120 (Missouri soil), 151 (California soil) and 135 (Florida soil). A Koc value of 66 was reported for 1,1,1-trichloroethane in an unspecified soil(2). According to a classification scheme(3), these Koc values suggests that 1,1,1-trichloroethane is expected to have high mobility in soil(SRC).

The Henry's Law constant of 1,1,1-trichloroethane is 0.0163 atm-cu m/mole(1). This Henry's Law constant indicates that 1,1,1-trichloroethane is expected to volatilize rapidly from water surfaces(2). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(2) is estimated as 3.4 hours(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 4.6 days(SRC). Laboratory measurements of the rate of evaporation of 1,1,1-trichloroethane from a stirred beaker containing distilled water resulted in a volatilization half-life of 25 minutes(3). 1,1,1-Trichloroethane's Henry's Law constant(1) indicates that volatilization from moist soil surfaces is expected to occur(SRC). 1,1,1-Trichloroethane is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 124 mm Hg at 25 °C(4).

GROUNDWATER: Raw groundwater in 13 United States cities had 1,1,1-trichloroethane levels of 1.1 ppb median, 13 ppb max, 23% were positive(1). 1,1,1-Trichloroethane has been detected in 18.9% of all groundwater samples analyzed from 178 sites designated as CERCLA (Comprehensive Emergency Response, Compensation and Liability Act) sites by the USEPA monitoring program(2). 1,1,1-Trichloroethane was detected in 19 of 1068 groundwater screening sites of the 1993-2001 Danish National Groundwater Monitoring Program at median and maximum concentrations of 0.06 and 0.39 ug/L respectively(3).

DRINKING WATER: 1,1,1-Trichloroethane was detected in samples of drinking water from 133 United States cities with finished surface water at 0.4 ppb (median), 3.3 ppb (max) and in 22% of the samples obtained from 23 United States cities with finished groundwater, 2.1 ppb (median), 3.0 (maximum)(1). Contaminated drinking water wells in New York, New Jersey, Connecticut and Maine have 1,1,1-trichloroethane concentrations of 950-5440 ppb(2). Results of the 1982 EPA Ground Water Supply Survey for 1,1,1-trichloroethane (466 samples) - 5.8% pos, 0.8 ppb median of positives, 18 ppb max(4). As part of EPA's Total Exposure Assessment Methodology (TEAM) study, the concentration of various toxic substances in drinking water of sample populations was measured(3). The mean (maximum) concentrations of 1,1,1-trichloroethane in Bayonne and Elizabeth, New Jersey, an industrial/chemical manufacturing area, were: 0.6 (5.3), 0.2 (2.6), and 0.2 (1.6) ppb in the fall 1981, summer 1982, and winter 1983, respectively(3). For comparison the drinking water of a sample of residents of a manufacturing city without a chemical or petroleum refining industry, Greensboro, NC and a small, rural, and agricultural town in North Dakota contained 0.03 (0.05) and 0.04 (0.07) ppb of 1,1,1-trichloroethane, respectively(3). 1,1,1-Trichloroethane was detected in 186 out of 1,095 samples (maximum concentration 10 ug/L) obtained from public wells and 70 out of 2,401 samples (maximum concentration 10 ug/L) from private wells in an assessment of about 2,400 domestic and 1,100 public wells conducted by the USGS from 1985-2001(5). 1,1,1-Trichloroethane was detected in 1,097 out of 16,116 community drinking water samples collected in the US from 1993-1998 at concentrations of 0.1-191 ug/L(6). In a 2006 national assessment of domestic wells sampled between 1985 and 2002, the US Geological Survey reported that 1,1,1-trichloroethane was detected in 103 of 1208 wells that were sampled(7).

SURFACE WATER: 1,1,1-Trichloroethane was detected in monitoring data from raw surface water in 105 cities in the United States at 0.2 ppb median, 1.2 ppb max, 12% positive(1). In a large study of the Ohio River Basin in 1980-1981 (4972 samples) 1,1,1-trichloroethane was detected in 33.6% of samples above 0.1 ppb, 3.9% between 1.0 and 0.3% above 10 ppb(2). In a study of 14 heavily industrialized river basins in 1975-1976, 9% of the sites had values above 1 ppb, and 8 ppb was the maximum value measured(3). At industrial sites, mean values are above 10 ppb with maximum values as high as 334 ppb(4). Concentration 20-800 meters away from outfalls of four producing plants and 1 user was 0.1-169 ppm(5). An analysis of Portugese coastal waters between April 1999 and May 2000 detected 1,1,1-trichloroethane in 92 of 644 samples with 68 samples at <0.1 ug/L and only 1 sample >1 ug/L(6).

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste numbers U226 and F002, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Trichloroethane is a waste chemical stream constituent which may be subjected to ultimate disposal by controlled incineration. Incineration, preferably after mixing with another combustible fuel; care must be exercised to assure complete combustion to prevent the formation of phosgene. An acid scrubber is necessary to remove the halo acids produced. /Trichloroethane/

A potential candidate for liquid injection incineration at a temperature range of 650 to 1,600 °C and a residence time of 0.1 to 2 seconds. A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids. A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids.

Chemical Treatability of 1,1,1-Trichloroethane; Concentration Process: Biological treatment; Chemical Classification: Halocarbon; Scale of Study: Full scale, continuous flow; Type of Wastewater Used: Industrial waste; Results of Study: Effluent concentration; 1.0-20.0 ppb (Survey of 2 municipal wastewater treatment plants).

For more Disposal Methods (Complete) data for 1,1,1-TRICHLOROETHANE (14 total), please visit the HSDB record page.

/GUIDE 160: HALOGENATED SOLVENTS/ Fire or Explosion: Some of these materials may burn, but none ignite readily. Most vapors are heavier than air. Air/vapor mixtures may explode when ignited. Container may explode in heat of fire.

/GUIDE 160: HALOGENATED SOLVENTS/ Health: Toxic by ingestion. Vapors may cause dizziness or suffocation. Exposure in an enclosed area may be very harmful. Contact may irritate or burn skin and eyes. Fire may produce irritating and/or toxic gases. Runoff from fire control or dilution water may cause pollution.

/GUIDE 160: HALOGENATED SOLVENTS/ Public Safety: CALL Emergency Response Telephone Number on Shipping Paper first. If Shipping Paper not available or no answer, refer to appropriate telephone number listed on the inside back cover. As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Many gases are heavier than air and will spread along ground and collect in low or confined areas (sewers, basements, tanks). Keep out of low areas. Ventilate closed spaces before entering.

/GUIDE 160: HALOGENATED SOLVENTS/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. Structural firefighters' protective clothing will only provide limited protection.

For more DOT Emergency Guidelines (Complete) data for 1,1,1-TRICHLOROETHANE (8 total), please visit the HSDB record page.

UN 2831; 1,1,1-Trichloroethane

IMO 6.1; 1,1,1-Trichloroethane.

49 633 75; 1,1,1-Trichloroethane

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

Do not transport with food and feedstuffs.

Symbol: Xn, N; Note: F; R: 20-59; S: (2)-24/25-59-61

UN Hazard Class: 6.1; UN Pack Group: III