dimethoxymethane

This chemical does not meet GHS hazard criteria for 1.2% (5 of 433) of reports.

H225 (98.8%): Highly Flammable liquid and vapor [Danger Flammable liquids]

H315 (18.5%): Causes skin irritation [Warning Skin corrosion/irritation]

H319 (42%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H335 (18.2%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P271, P280, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P319, P321, P332+P317, P337+P317, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 433 reports by companies from 19 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 5 of 433 reports by companies.

There are 18 notifications provided by 428 of 433 reports by companies with hazard statement code(s).

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.

H225: Highly Flammable liquid and vapor [Danger Flammable liquids]

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

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]

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

Fresh air, rest. Refer for medical attention.

First rinse with plenty of water for at least 15 minutes, then remove contaminated clothes and rinse again.

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

Rinse mouth. Do NOT induce vomiting. Refer for medical attention .

Excerpt from NIOSH Pocket Guide for Methylal:

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: WATER FLUSH PROMPTLY - If this chemical contacts the skin, flush the contaminated skin with water promptly. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water promptly. If irritation persists after washing, get medical attention.

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Swallow: MEDICAL ATTENTION IMMEDIATELY - If this chemical has been swallowed, get medical attention immediately. (NIOSH, 2024)

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.

· In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin.

In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product. Please consult the shipping paper and/or the "ERAP" section.

(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: Water flush promptly - If this chemical contacts the skin, flush the contaminated skin with water promptly. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water promptly. If irritation persists after washing, get medical attention.

Breathing: Respiratory support

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

Excerpt from ERG Guide 127 [Flammable Liquids (Water-Miscible)]:

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient. CAUTION: For fire involving UN1170, UN1987 or UN3475, alcohol-resistant foam should be used. CAUTION: Ethanol (UN1170) can burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.).

SMALL FIRE: Dry chemical, CO2, water spray or alcohol-resistant foam.

LARGE FIRE: Water spray, fog or alcohol-resistant foam. Avoid aiming straight or solid streams directly onto the product. If it can be done safely, move undamaged containers away from the area around the fire.

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. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2024)

Use water spray, dry powder, carbon dioxide, alcohol-resistant foam. In case of fire: keep drums, etc., cool by spraying with water.

TO FIGHT FIRE: FOAM, CARBON DIOXIDE, DRY CHEMICAL ...

Water may be ineffective. Alcohol foam.

· 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.

· 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.

· All equipment used when handling the product must be grounded.

· Do not touch or walk through spilled material.

· Stop leak if you can do it without risk.

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

· A vapor-suppressing foam may be used to reduce vapors.

· Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers.

· Use clean, non-sparking tools to collect absorbed material.

Large Spill

· Dike far ahead of liquid spill for later disposal.

· Water spray may reduce vapor, but may not prevent ignition in closed spaces.

Excerpt from ERG Guide 127 [Flammable Liquids (Water-Miscible)]:

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 300 meters (1000 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 300 meters (1000 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.

Consult an expert! Personal protection: filter respirator for organic vapours of low boiling point adapted to the airborne concentration of the substance. Remove all ignition sources. Cover the spilled material with sand or other non-combustible material. Collect leaking liquid in covered containers. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.

1. REMOVE ALL IGNITION SOURCES. 2. VENTILATE AREA OF SPILL OR LEAK. 3. FOR SMALL QUANTITIES, ABSORB ON PAPER TOWELS. EVAPORATE IN SAFE PLACE (SUCH AS FUME HOOD). ALLOW SUFFICIENT TIME TO COMPLETELY CLEAR HOOD DUCTWORK. BURN PAPER IN SUITABLE LOCATION AWAY FROM COMBUSTIBLE MATERIALS. 3. LARGE QUANTITIES CAN BE COLLECTED, DISSOLVED IN ALC OF GREATER MOLECULAR WT THAN BUTYL ALC, & ATOMIZED IN SUITABLE COMBUSTION CHAMBER. METHYLAL SHOULD NOT BE ALLOWED TO ENTER CONFINED SPACE, SUCH AS SEWER, BECAUSE OF THE POSSIBILITY OF AN EXPLOSION.

... MAY BE DISPOSED OF BY DISSOLVING IN ALCOHOL OF GREATER MOLECULAR WEIGHT THAN BUTYL ALCOHOL & ATOMIZING IN SUITABLE COMBUSTION CHAMBER.

SRP: The scientific literature supports the wearing of contact lenses in industrial environments, as part of a program to protect the eye against chemical compounds and minerals causing eye irritation. 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.

SAFE-HANDLING PRECAUTIONS SHOULD INCL USE OF ADEQUATE VENTILATION TO BE CERTAIN THAT AVG CONCN ARE WELL BELOW 1000 PPM, & AVOIDANCE OF EXCESSIVE OR PROLONGED SKIN CONTACT. METHYLAL SHOULD BE HANDLED WITH DUE REGARD FOR ITS FLAMMABLE PROPERTIES.

To prevent injury from occurring as a result of contact with an aldehyde in the form of liquid or vapor, the process in which the substance is present should, if possible be conducted in enclosed plant. If openings are necessary for the purposes of manipulation, vapor should be prevented from escaping into the workroom by the application of exhaust ventilation to the plant or enclosure. When the process cannot be enclosed, exhaust ventilation hoods should be fitted to trap and extract escaping vapor before it can diffuse into the workroom atmosphere. /Aldehydes and ketals/

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

Work clothing that becomes wet should be immediately removed due to its flammability hazard.

Excerpt from ERG Guide 127 [Flammable Liquids (Water-Miscible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2024)

Fireproof. Separated from strong oxidants and strong bases. Cool. Keep in the dark. Well closed. Store only if stabilized. Store in an area without drain or sewer access.

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

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

500.0 [ppm]

1000 [ppm]

2500 [ppm]

15000 [ppm]

1000 ppm (3100 mg/m³)

TWA 1000 ppm (3100 mg/m3)

1000.0 [ppm]

2200 ppm ; Based on 10% of the lower explosive limit. (NIOSH, 2024)

2200.0 [ppm]

Excerpts from Documentation for IDLHs: Other animal data: In one study, the no effect levels were determined to be 2,810 and 8,450 ppm in rats and guinea pigs, respectively [Price et al. 1978]. Fifteen 7­hour exposures to 11,000 ppm caused only minor irritation in 50 mice [Weaver et al. 1951]. . . .Human data: Methylal has been used as an anesthetic in surgery [ACGIH 1991].

2200 ppm [Based on 10% of the lower explosion limit for safety considerations even though the relevant toxicological data indicated that irreversible health efects or impairment of escape existed only at higher concentrations.]

2200 ppm

2200 ppm [10%LEL]

See: 109875

8 hr Time Weighted Avg (TWA): 1000 ppm.

Excursion Limit Recommendation: Excursions in worker exposure levels may exceed 3 times the TLV-TWA for no more than a total of 30 minutes during a work day, and under no circumstances should they exceed 5 times the TLV-TWA, provided that the TLV-TWA is not exceeded.

1000 ppm as TWA.

1000 ppm [1970]

1600 mg/m

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient.

CAUTION: For fire involving UN1170, UN1987 or UN3475, alcohol-resistant foam should be used.

CAUTION: Ethanol (UN1170) can burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.)

Small Fire

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

Large Fire

· Water spray, fog or alcohol-resistant foam.

· Avoid aiming straight or solid streams directly onto the product.

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

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.

· For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn.

A harmful contamination of the air can be reached rather quickly on evaporation of this substance at 20 °C.

The substance is irritating to the eyes and respiratory tract. The substance may cause effects on the central nervous system. Exposure far above the OEL could cause unconsciousness.

The substance defats the skin, which may cause dryness or cracking.

Excerpt from NIOSH Pocket Guide for Methylal:

Methylal appears as a clear colorless liquid with a chloroform-like odor. Flash point 0 °F. Boiling point 42.3 °C. Density 0.864 g / cm3 at 68 °F (20 °C). Vapors heavier than air.

Colorless liquid with a chloroform-like odor; [NIOSH]

VERY VOLATILE COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR.

Colorless liquid with a chloroform-like odor.

COLORLESS, CLEAR LIQUID

Colorless solid.

CHLOROFORM ODOR

Chloroform-like odor.

PUNGENT TASTE

108 °F at 760 mmHg (USCG, 1999)

41.6 °C @ 760 MM HG

42 °C @760 [mm Hg]

-157 °F (USCG, 1999)

-105.1 °C

0 °F (USCG, 1999)

-26 °F (-32 °C) (OPEN CUP)

-31 °C c.c.

-26 °F (open cup)

(oc) -26 °F

33 % (NIOSH, 2024)

MISCIBLE WITH ALCOHOL, ETHER, OILS; SOL IN 3 PARTS WATER

SOL IN ALL ACETONE, AND BENZENE

Water solubility: 330,000 mg/l

Solubility in water, g/100ml at 20 °C: 28.5 (good)

0.861 at 68 °F (USCG, 1999) - Less dense than water; will float

0.8593 @ 20 °C/4 °C

0.86 g/cm³

Relative density of the vapour/air-mixture at 20 °C (air = 1): 1.7

0.8593 @ 20°C

2.6 (USCG, 1999) - Heavier than air; will sink (Relative to Air)

2.6 (AIR= 1)

Relative vapor density (air = 1): 2.6

337.08 mmHg at 70 °F (USCG, 1999)

400.0 [mmHg]

400 MM HG AT 25 °C

Vapor pressure, kPa at 20 °C: 42.6

330 mmHg

750 [mm Hg] @41.7 °C

log Kow= 0.0

Henry's Law constant= 1.63X10-4 atm-cu m/mole (calc).

Highly flammable. Water soluble.

Acetals, Ketals, Hemiacetals, and Hemiketals

Highly Flammable

METHYLAL, an acetal, is incompatible with strong oxidizing agents and acids (NIOSH, 2024). Breaks down to formaldehyde and methanol in acidic solutions. A very dangerous fire hazard when exposed to heat, flame or oxidizing agents. May ignite or explode if heated with oxygen [Lewis].

Strong oxidizers, acids.

Strong oxidizers, acids

Dimethoxymethane

D: Other compounds that may form peroxides

2 samples had >100 ppm peroxide; age 2-10 yrs

Molem, M. J. et al., Chem. Abs., 1975, 83, 45495

Dimethoxymethane

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

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

inhalation, ingestion, skin and/or eye contact

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

Dry skin.

Redness. Pain.

Abdominal pain. Nausea. Vomiting. Further see Inhalation.

irritation eyes, skin, upper respiratory system; anesthesia

Eyes, skin, respiratory system, central nervous system

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.

LC50 (mice) = 57,000 mg/m3/7H

LDLo Guinea pig sc 3013 mg/kg

LC50 Mouse inhalation 18,000 ppm/7 hr

LC50 Guinea pig sc 5 g/kg

If methylal gets into the eyes, wash eyes immediately with large amounts of water, lifting the lower and upper lids occasionally. If irritation is present after washing, get medical attention. Contact lenses should not be worn when working with this chemical.

If methylal gets on the skin, promptly wash the contaminated skin with water, if the methylal has not already evaporated. If methylal soaks through the clothing, remove the clothing immediately and flush the skin with water. If irritation persists after washing, get medical attention. If there is skin irritation, get medical attention.

If a person breathes in large amounts of methylal, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Move the affected person from the hazardous exposure. If the exposed person has been overcome, notify someone else and put into effect the established emergency rescue procedures. Do not become a casualty. Understand the facility's emergency rescue procedures and know the locations of rescue equipment before the need arises.

Irrigate eyes with water.

... PROPERTIES OF SIMPLE UNSUBSTITUTED ACETALS ARE CHARACTERIZED BY ETHER-LIKE ANESTHETIC ACTION, & BY RELATIVELY LOW DEGREE OF PRIMARY IRRITATION COMPARED TO PARENT ALDEHYDE. /ACETALS/

INHALATION CAUSES IRRITATION OF RESP SYSTEM & DEPRESSION OF CNS. LIQ CAUSES IRRITATION OF EYES & WILL IRRITATE SKIN IF ALLOWED TO REMAIN.

... EFFECTS ... ON GUINEA PIGS & MICE. AT EXTREMELY HIGH LEVELS, 153,000 PPM, ANESTHESIA OCCURRED IN 20 MINUTES & DEATH OCCURRED IN ABOUT 2 HR. ... EVIDENCE OF IRRITATION ... NOTED IN GUINEA PIGS INCLUDED SQUINTING, LACRIMATION, SNEEZING, & NASAL DISCHARGE. ... EYE & RESP TRACT IRRITATION ... @ LOWER LEVELS ... LC50 IN MICE FOR 7 HR EXPOSURE WAS FOUND TO BE ABOUT 18,000 PPM.

GROUP OF 50 MICE RECEIVED FIFTEEN 7 HR EXPOSURES @ CONCN OF APPROX 11,000 PPM. ONLY MINOR IRRITATION ... NOTED ... ALTHOUGH LACK OF COORDINATION APPEARED AFTER ABOUT 3 OR 4 HR OF EXPOSURE. ... 6 DEATHS OCCURRED IN THE 50 ANIMALS DURING THE EXPERIMENT. MICE EXPOSED TO 14,000 PPM SHOWED ... GREATER DEGREE OF ANESTHESIA. ABOUT 30% ... SUCCUMBED DURING 17 DAY EXPOSURE.

GUINEA PIGS SACRIFICED 16-74 HR AFTER EXPOSURE TO VERY HIGH LEVELS SHOWED ... FATTY DEGENERATION OF LIVER & KIDNEY, & EXTENSIVE BRONCHOPNEUMONIA.

MICE HAVING ABOUT FIFTEEN 7 HR EXPOSURES @ LEVELS UP TO 14,000 PPM SHOWED ... EVIDENCE OF PULMONARY EDEMA & ... CHANGES IN KIDNEY. ... NO CHANGES ... IN OPTIC NERVES OR RETINAS ... THAT COULD BE ATTRIBUTED TO METHYLAL. OCCASIONALLY SOME CORNEAL BLEBS ... SEEN, BUT THESE COULD NOT BE ATTRIBUTED WITH CERTAINTY TO METHYLAL EXPOSURE.

EXPOSURES OF MICE AND GUINEA PIGS TO HIGHER CONCN OF ... VAPOR THAN WOULD BE ENCOUNTERED INDUSTRIALLY FOUND TO CAUSE DAMAGE TO THE LUNGS, LIVER, HEART, AND KIDNEYS, AND OCCASIONAL SUPERFICIAL IRRITATION OF THE EYES. ...

Environmental effects of the substance have been adequately investigated, but no significant effects have been found.

Methylal may be released to the environment as a result of its manufacture and use as a solvent, in organic synthesis, perfumes, reagents, and coatings. Methylal is highly volatile and if released on land or in water, it would rapidly volatilize. Its estimated half-life in a model river is 7.2 hr. Adsorption to soil and sediment and bioconcentration will not be important fate processes. The importance of hydrolysis and biodegradation is unknown. In the atmosphere, methylal will degrade by reaction with photochemically produced hydroxyl radicals. Its estimated half-life in the atmosphere is 2.3 days. Exposure to methylal will be primarily occupational through inhalation and dermal contact. (SRC)

Methylal used as a solvent and reagent in organic synthesis(2) may be released to the environment in waste water and as fugitive emissions relating to its manufacture and use. Mean vapor emission rates of methylal measured at two locations at an industrial waste water treatment facility in December were 28.6 and 14.7 mg/min sq-m, at which time the ambient and liquid surface temperatures were 6 and 15 °C, respectively(1).

METHYLAL WAS ONE OF THE COMPONENTS IN WASTE WATER FROM A UREA-FORMALDEHYDE GLUE PLANT.

TERRESTRIAL FATE: If released on land, methylal would volatilize rapidly due to its high vapor pressure and Henry's Law constant and low adsorptivity to soil. It would also exhibit high mobility in soil. The importance of biodegradation in soil is unknown. (SRC)

AQUATIC FATE: If released to water, methylal will be primarily lost through volatilization. Its half-life in a model river is estimated from a calculated Henry's Law constant to be 7.2 hr(1-3). Adsorption to sediment and particulate matter in the water column, and bioconcentration should not be important. The importance of biodegradation in water is unknown. Hydrolysis is fairly slow(SRC).

ATMOSPHERIC FATE: The atmosphere is the sink for methylal. In the atmosphere, methylal will degrade by reaction with photochemically-produced hydroxyl radicals. The half-life for this reaction is estimated to be 2.3 days(1). Methylal is highly soluble in water, 2.44X10+5 ppm(2), and would be washed out by rain. However, methylal thus remove would be recycled back into the atmosphere. (SRC)

A reduction in BOD in 8 hr was obtained in one study in which well acclimated sewage seed was incubated with 333 ppm of methylal(1). However this reduction was small compared with the theoretical oxygen demand and toxicity resulted in an initial increase in BOD.

Vapor phase methylal will react with photochemically-produced hydroxyl radicals in the atmosphere by H abstraction. The estimated rate of this reaction is 6.69X10-12 cu cm/molec-sec(5). Assuming a hydroxyl radical concn of 5X10+5 per cu cm, the half-life of methylal in the atmosphere is 2.3 days. Methylal is an acetal. These chemicals are stable toward bases, but readily hydrolyzed by acid(2). However, hydrolysis rates are not available under environmental conditions. Since methylal has been measured in effluents in surface water and drinking water, hydrolysis must be fairly slow(SRC).

The BCF for methylal, estimated from its octanol/water partition coefficient, 0.00(1), using a recommended regression equation is 0.6(2,SRC). Therefore, methylal should not bioconcentrate in fish and aquatic organisms.

The Koc for methylal estimated from its water solubility, 2.44X10+5 ppm(1), by a recommended regression equation is 5(2). Therefore methylal would be very mobile in soil(3).

Environmental effects of the substance have been adequately investigated, but no significant effects have been found.

Methylal may be released to the environment as a result of its manufacture and use as a solvent, in organic synthesis, perfumes, reagents, and coatings. Methylal is highly volatile and if released on land or in water, it would rapidly volatilize. Its estimated half-life in a model river is 7.2 hr. Adsorption to soil and sediment and bioconcentration will not be important fate processes. The importance of hydrolysis and biodegradation is unknown. In the atmosphere, methylal will degrade by reaction with photochemically produced hydroxyl radicals. Its estimated half-life in the atmosphere is 2.3 days. Exposure to methylal will be primarily occupational through inhalation and dermal contact. (SRC)

Methylal used as a solvent and reagent in organic synthesis(2) may be released to the environment in waste water and as fugitive emissions relating to its manufacture and use. Mean vapor emission rates of methylal measured at two locations at an industrial waste water treatment facility in December were 28.6 and 14.7 mg/min sq-m, at which time the ambient and liquid surface temperatures were 6 and 15 °C, respectively(1).

METHYLAL WAS ONE OF THE COMPONENTS IN WASTE WATER FROM A UREA-FORMALDEHYDE GLUE PLANT.

TERRESTRIAL FATE: If released on land, methylal would volatilize rapidly due to its high vapor pressure and Henry's Law constant and low adsorptivity to soil. It would also exhibit high mobility in soil. The importance of biodegradation in soil is unknown. (SRC)

AQUATIC FATE: If released to water, methylal will be primarily lost through volatilization. Its half-life in a model river is estimated from a calculated Henry's Law constant to be 7.2 hr(1-3). Adsorption to sediment and particulate matter in the water column, and bioconcentration should not be important. The importance of biodegradation in water is unknown. Hydrolysis is fairly slow(SRC).

ATMOSPHERIC FATE: The atmosphere is the sink for methylal. In the atmosphere, methylal will degrade by reaction with photochemically-produced hydroxyl radicals. The half-life for this reaction is estimated to be 2.3 days(1). Methylal is highly soluble in water, 2.44X10+5 ppm(2), and would be washed out by rain. However, methylal thus remove would be recycled back into the atmosphere. (SRC)

A reduction in BOD in 8 hr was obtained in one study in which well acclimated sewage seed was incubated with 333 ppm of methylal(1). However this reduction was small compared with the theoretical oxygen demand and toxicity resulted in an initial increase in BOD.

Vapor phase methylal will react with photochemically-produced hydroxyl radicals in the atmosphere by H abstraction. The estimated rate of this reaction is 6.69X10-12 cu cm/molec-sec(5). Assuming a hydroxyl radical concn of 5X10+5 per cu cm, the half-life of methylal in the atmosphere is 2.3 days. Methylal is an acetal. These chemicals are stable toward bases, but readily hydrolyzed by acid(2). However, hydrolysis rates are not available under environmental conditions. Since methylal has been measured in effluents in surface water and drinking water, hydrolysis must be fairly slow(SRC).

The BCF for methylal, estimated from its octanol/water partition coefficient, 0.00(1), using a recommended regression equation is 0.6(2,SRC). Therefore, methylal should not bioconcentrate in fish and aquatic organisms.

The Koc for methylal estimated from its water solubility, 2.44X10+5 ppm(1), by a recommended regression equation is 5(2). Therefore methylal would be very mobile in soil(3).

The Henry's Law constant for methylal calculated from its vapor pressure, 398 mm Hg(1), and water solubility, 2.44X10+5 ppm(2), is 1.63X10-4 atm-cu m/mole. Using this Henry's Law constant, one estimates that the volatilization half-life of methylal from a model river 1 m deep, flowing 1 m/sec with a 3 m/sec wind speed is 7.2 hr(3,SRC). In view of its high vapor pressure and Henry's Law constant and low adsorption to soil, methylal would volatilize rapidly from soil.

DRINKING WATER: Detected in 2 cities in the U.S. (Miami and Philadelphia) using volatile organic analysis but not quantified.

DRINKING WATER: Identified, but not quantified in drinking water in the USA(1). Identified in concentrate from the Seattle, WA water supply, but not in that of six other US cities(2).

SURFACE WATER: In a survey of 204 surface waters across the US affected by industrial pollutants from a range of industries, 10 waters were found to contain methylal(2).

In a comprehensive survey of wastewater from 4000 industrial and publicly owned treatment works (POTWs) sponsored by the Effluent Guidelines Division of the U.S. EPA, methylal was identified in discharges of the following industrial category (positive occurrences; median concn in ppb): leather tanning (1; 1637.5), plastics and synthetics (3; 30.8), organic chemicals (6; 45.6), publicly owned treatment works (3; 5.0)(1). The highest effluent concn was 1637 ppb in the leather tanning industry(1). Detected in effluent concentrates from the advanced treatment plant in Orange County, CA, but not in that of five other communities(2).

Exposure to methylal will be primarily occupational through inhalation and dermal contact. Users of perfume containing methylal will be similarly exposed. (SRC)

NIOSH (NOES Survey 1981-1983) has statistically estimated that 135,972 workers are exposed to methylal in the USA(1).

In the EPA National Human Adipose Survey for fiscal year 1982, 46 composite samples categorized broadly by region and age group were analyzed for pollutants(1). Methylal was identified in one sample from the northeast US in the >45 age group.

... MAY BE DISPOSED OF BY DISSOLVING IN ALCOHOL OF GREATER MOLECULAR WEIGHT THAN BUTYL ALCOHOL & ATOMIZING IN SUITABLE COMBUSTION CHAMBER.

/GUIDE 127: FLAMMABLE LIQUIDS (Polar/Water-Miscible)/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.

/GUIDE 127: FLAMMABLE LIQUIDS (Polar/Water-Miscible)/ Health: Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control may cause pollution.

/GUIDE 127: FLAMMABLE LIQUIDS (Polar/Water-Miscible)/ 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. Keep out of low areas. Ventilate closed spaces before entering.

/GUIDE 127: FLAMMABLE LIQUIDS (Polar/Water-Miscible)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection.

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

UN 1234; Methylal

IMO 3.0; Methylal

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.

Flammable Liquid

Airtight.

UN Hazard Class: 3; UN Pack Group: II