Methanesulfonic Acid

H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

P260, P264, P280, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P321, P363, P405, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for < 0.1% (1 of 1373) of reports.

H290 (32.3%): May be corrosive to metals [Warning Corrosive to Metals]

H302+H312 (45.7%): Harmful if swallowed or in contact with skin [Warning Acute toxicity, oral; acute toxicity, dermal]

H302 (60.9%): Harmful if swallowed [Warning Acute toxicity, oral]

H312 (61.5%): Harmful in contact with skin [Warning Acute toxicity, dermal]

H314 (> 99.9%): Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

H318 (53.9%): Causes serious eye damage [Danger Serious eye damage/eye irritation]

H335 (25.9%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

P234, P260, P261, P264, P264+P265, P270, P271, P280, P301+P317, P301+P330+P331, P302+P352, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P319, P321, P330, P362+P364, P363, P390, P403+P233, P405, P406, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 1373 reports by companies from 33 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 1 of 1373 reports by companies.

There are 32 notifications provided by 1372 of 1373 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.

H301: Toxic if swallowed [Danger Acute toxicity, oral]

H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]

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

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

P203, P260, P261, P264, P264+P265, P270, P271, P280, P301+P316, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P318, P321, P330, P363, P405, and P501 (click each P-code to see the statement)

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.

Special protective equipment for fire-fighters: Wear self contained breathing apparatus for fire fighting if necessary.

SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

Personal precautions: Use personal protective equipment. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Environmental precautions: Do not let product enter drains. Methods for cleaning up: Soak up with inert absorbent material and dispose of as hazardous waste. Keep in suitable, closed containers for disposal.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Observe all federal, state, and local environmental regulations. Contact a licensed professional waste disposal service to dispose of this material. Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber.

Hygiene measures: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.

In case of skin contact: Take off contaminated clothing and shoes immediately. Wash off with soap and plenty of water. Consult a physician.

In case of eye contact: Rinse thoroughly with plenty of water for at least 15 minutes and consult a physician.

Store in cool place. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Recommended storage temperature: 2 - 8 °C. Heat sensitive.

0.18 [ppm]

2.8 [ppm]

17 [ppm]

Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face respirator with multipurpose combination (US) or type ABEK (EN 14387) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).

Hand protection: The selected protective gloves have to satisfy the specifications of EU Directive 89/686/EEC and the Standard EN 374 derived from it. Handle with gloves.

Eye protection: Safety glasses.

Skin and body protection: Choose body protection according to the amount and concentration of the dangerous substance at the work place.

Liquid; Liquid; Other Solid

Liquid at room temperature; [HSDB] White crystals below 20 deg C; [CHEMINFO] Light yellow liquid; mp = 17-19 deg C; [Aldrich MSDS]

Liquid at room temperature

167 °C at 10 mm Hg

189 °C closed cup

Solubility at 26-28 °C in wt %: hexane, 0; benzene, 1.5; methylcyclopentane, 0; toluene, 0.38; o-chlorotoluene, 0.23; ethyl disulfide, 0.47

Soluble in alcohol, ether

Soluble in water

In water, 1X10+6 mg/L at 20 °C /Miscible/

1.4812 g/cu cm at 18 °C

1.4812 @ 18°C

0.000428 [mmHg]

4.28X10-4 mm Hg at 25 °C

Thermally stable at moderately elevated temperatures.

> 500 °C at 1013 mm Hg

Hazardous decomposition products formed under fire conditions: Carbon oxides, Sulfur oxides

Corrosive to iron, steel, brass, copper, lead

5.0584X10-2 N/m at melting point

Index of refraction: 1.4317 at 18 °C

pKa = -1.86

Not hydrolyzed by boiling water or hot aqueous alkali

Liquid molar volume = 0.065051 cu meter/kmol

Other Classes -> Sulfonic Acids, Alkyl

Corrosives

Ionic Liquids

Materials to avoid: Amines, strong reducing agents, strong oxidizing agents, bases

Explosive reaction with ethyl vinyl ether.

Incompatible with hydrogen fluoride.

Methanesulfonic acid is too powerful a catalyst for O-alkylation with the vinyl ether, causing explosive polymerisation of the latter on the multimol scale. Dichloroacetic acid is a satisfactory catalyst on the 3 g mol scale.

Neurotoxin - Other CNS neurotoxin

Dermatotoxin - Skin burns.

Toxic Pneumonitis - Inflammation of the lungs induced by inhalation of metal fumes or toxic gases and vapors.

LC50 (rat) = >330 ppm/6hr

LC50 Rat inhalation 330 ppm for 6 hr

LD50 Rat oral 200-400 mg/kg

LD50 Mouse oral 6200 mg/kg (neutralized 70% Methanesulfonic acid)

LD50 Guinea pig dermal > 2,000 mg/kg

For more Non-Human Toxicity Values (Complete) data for Methanesulfonic acid (6 total), please visit the HSDB record page.

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Silane, Chlorosilane, and Related Compounds/

Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if necessary ... . Monitor for shock and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal (refer to ingestion protocol in Section Three ... . Cover skin burns with sterile dressings after decontamination ... . /Silane, Chlorosilane, and Related Compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Early intubation at the first sign of upper airway obstruction may be necessary. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Silane, Chlorosilane, and related compounds/

/SIGNS AND SYMPTOMS/ Corrosive to tissues (eyes, skin, mucous membranes).

/SIGNS AND SYMPTOMS/ May be harmful if inhaled. Material is extremely destructive to the tissue of the mucous membranes and upper respiratory tract. May be harmful if absorbed through skin. Causes skin burns. Causes eye burns.

/LABORATORY ANIMALS: Acute Exposure/ Both anhydrous and 70% methanesulfonic acid were corrosive to mouse skin by the anesthetized tail method after a 1 hr exposure.

/LABORATORY ANIMALS: Acute Exposure/ Methanesulfonic acid was corrosive to rabbit eyes and caused immediate pain and necrosis of all ocular tissue.

/LABORATORY ANIMALS: Acute Exposure/ No adverse effects on body weight, liver, or kidney weights or gross pathology were observed in rats fed methanesulfonic acid or its potassium salt in the diet for 1 wk at dosage levels of up to 2000 mg/kg.

/LABORATORY ANIMALS: Acute Exposure/ No effect in rats after 6 hr of inhaling vapor from heated liq. /From table/

For more Non-Human Toxicity Excerpts (Complete) data for Methanesulfonic acid (19 total), please visit the HSDB record page.

Methansulfonic acid (CAS # 75-75-2) undiluted, was evlauated for acute peroral toxicity. The LD50 for non-fasted male rats was 0.281 ml/kg. Dosage and mortality data are as follows: 0.25 (2/5), 0.5 (5/5), and 1.0 (2/3) ml/kg. Clinical signs at all doses included sluggishnes and unsteady gait. Gross pathology included livers mottled and burned; stomachs burned; pylorus hemorrhaged and gas filled; intestines hemorrhaged, injected, and gas filled; and kidneys mottled and slightly congested. The test substance was found to be highly toxic following acute peroral intubation.

Methansulfonic acid (CAS # 75-75-2) was evlauated for subchronic toxicity. The test substance was administered to Harlan-Wistar albino rats at doses of 0, 10, 50, 200, or 500 mg/kg in the diets. As no effect was visible after the first day of dosing, the 10 mg/kg was increased to 2000 mg/kg. None of the rats died in this study. There was no significant effect during the remainder of the 7 days of treatment and none of the criteria of stress measured (appetite, body weight change, liver and kidney weight) were significantly altered.

Methanesulfonic acid was evaluated in an epidemiology study. The methodology used to assess health effects from potential exposure included a work/family history questionnaire; physical measurements; chest x-ray; pulmonray function tests; general blood chemistries; CBC with indices and differential; urinalysis; urinary phenol; sputum cytology; and a physician's examination. The workforce consisted of 10 male employees. Chest x-rays, sputum cytology, all liver and kidney function tests, and urine pheonol were normal; and no serious blood disorder or skin disorder was reported. It was determined that there was no evidence of hematolgoical, biochemical or clinical aberrations caused by occupational exposures. One person may have an allegic response to contact with cellosolve.

EC50; Species: Daphnia magna (Crustacea); Concentration 1.7 mg/L for 24 hr; Effect: immobilization /Conditions of bioassay not specified in source/

EC50; Species: Daphnia pulex (Crustacea); Concentration: 33 mg/L for 24 hr /Conditions of bioassay not specified in source/

EC50; Species: Daphnia pulex (Crustacea); Concentration: 12 mg/L for 48 hr/ Conditions of bioassay not specified in source/

EC50; Species: Selenastrum capricornutum /Freshwater algae/; Conditions: freshwater, static (pH 7.5-9.4); Concentration: 7.2 mg/L for 96 hr (pH 8.3); Effect: inhibition of cell multiplication

For more Ecotoxicity Values (Complete) data for Methanesulfonic acid (9 total), please visit the HSDB record page.

Methanesulfonic acid's production and use as a catalyst in esterification, alkylation, olefin polymerization, and peroxidation reactions and as a solvent may result in its release to the environment through various waste streams. Methanesulfonic acid is produced by atmospheric hydrolysis of dimethyl sulfoxide, which itself is produced from naturally-derived dimethyl sulfide. If released to air, a vapor pressure of 4.28X10-4 mm Hg at 25 °C indicates methanesulfonic acid will exist solely as a vapor. Vapor-phase methanesulfonic acid 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 58 days. Methanesulfonic acid does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight. If released to soil, methanesulfonic acid is expected to have very high mobility based upon an estimated Koc of 1. The pKa of methanesulfonic acid is -1.86, indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts. Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks indicating that biodegradation is an important environmental fate process. If released into water, methanesulfonic acid is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. The pKa indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process. Methanesulfonic acid is miscible with water and therefore bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. Occupational exposure to methanesulfonic acid may occur through inhalation and dermal contact with this compound at workplaces where methanesulfonic acid is produced or used. Monitoring data indicate that the general population may be exposed to methansulfonic acid via inhalation of ambient air; methanesulfonic acid is widely detected in marine air. (SRC)

Methanesulfonic acid is produced by atmospheric hydrolysis of dimethyl sulfoxide(1), which itself is produced from the atmospheric photochemical oxidation of dimethyl sulfide, which comes from marine algae and salt marsh plants(2).

Methanesulfonic acid's production and use as a catalyst in esterification, alkylation, olefin polymerization, peroxidation reactions(1) and as a solvent(2) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that methanesulfonic acid is expected to have very mobility in soil(SRC). The pKa of methanesulfonic acid is -1.86(3), indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. Methanesulfonic acid is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 4.28X10-4 mm Hg at 25 °C(5). Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks(6) indicating that biodegradation is an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that methanesulfonic acid is not expected to adsorb to suspended solids and sediment(SRC). A pKa of -1.86(3) indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process(4). Methanesulfonic acid is miscible with water(5) and therefore bioconcentration in aquatic organisms is low(SRC). Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks(6) indicating that biodegradation is an important environmental fate process in water(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methanesulfonic acid, which has a measured vapor pressure of 4.28X10-4 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase methanesulfonic acid 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 58 days(SRC), calculated from its rate constant of 2.8X10-13 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Methanesulfonic acid does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

AEROBIC: Methanesulfonic acid, present at 100 mg/L, reached 100% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test(1).

The rate constant for the vapor-phase reaction of methanesulfonic acid with photochemically-produced hydroxyl radicals has been estimated as 2.8X10-13 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 58 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Methanesulfonic acid is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). Methanesulfonic acid does not contain chromophores that absorb at wavelengths >290 nm(2) and therefore is not expected to direct photolysis by sunlight(SRC).

Methanesulfonic acid is miscible with water(1) and therefore bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of methanesulfonic acid can be estimated to be 1(SRC). According to a classification scheme(2), this estimated Koc value suggests that methanesulfonic acid is expected to have very high mobility in soil. The pKa of methanesulfonic acid is -1.86(3), indicating that this compound will almost entirely exist in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4).

A pKa of -1.86(1) indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces or moist soil surfaces is not expected to be an important fate process(2). Methanesulfonic acid is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure of 4.28X10-4 mm Hg(3).

RAINWATER: Methanesulfonic acid was detected in rainwater ranging from 41.9 (July 1996) to 1325.8 (December 1996) neq/L (volume weighted monthly mean concentrations) collected at Amsterdam Island in the Southern Indian Ocean, sampled from December 1995 to February 1997(1).

ICE/SNOW: The methanesulfonate ion was found to be present at a mean concentration of 0.08 microequivalents/L and ranged between 0.006 and 0.28 microequivalents/L in Antarctic ice from Law Dome(1).

EC50; Species: Daphnia magna (Crustacea); Concentration 1.7 mg/L for 24 hr; Effect: immobilization /Conditions of bioassay not specified in source/

EC50; Species: Daphnia pulex (Crustacea); Concentration: 33 mg/L for 24 hr /Conditions of bioassay not specified in source/

EC50; Species: Daphnia pulex (Crustacea); Concentration: 12 mg/L for 48 hr/ Conditions of bioassay not specified in source/

EC50; Species: Selenastrum capricornutum /Freshwater algae/; Conditions: freshwater, static (pH 7.5-9.4); Concentration: 7.2 mg/L for 96 hr (pH 8.3); Effect: inhibition of cell multiplication

For more Ecotoxicity Values (Complete) data for Methanesulfonic acid (9 total), please visit the HSDB record page.

Methanesulfonic acid's production and use as a catalyst in esterification, alkylation, olefin polymerization, and peroxidation reactions and as a solvent may result in its release to the environment through various waste streams. Methanesulfonic acid is produced by atmospheric hydrolysis of dimethyl sulfoxide, which itself is produced from naturally-derived dimethyl sulfide. If released to air, a vapor pressure of 4.28X10-4 mm Hg at 25 °C indicates methanesulfonic acid will exist solely as a vapor. Vapor-phase methanesulfonic acid 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 58 days. Methanesulfonic acid does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight. If released to soil, methanesulfonic acid is expected to have very high mobility based upon an estimated Koc of 1. The pKa of methanesulfonic acid is -1.86, indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts. Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks indicating that biodegradation is an important environmental fate process. If released into water, methanesulfonic acid is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. The pKa indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process. Methanesulfonic acid is miscible with water and therefore bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. Occupational exposure to methanesulfonic acid may occur through inhalation and dermal contact with this compound at workplaces where methanesulfonic acid is produced or used. Monitoring data indicate that the general population may be exposed to methansulfonic acid via inhalation of ambient air; methanesulfonic acid is widely detected in marine air. (SRC)

Methanesulfonic acid is produced by atmospheric hydrolysis of dimethyl sulfoxide(1), which itself is produced from the atmospheric photochemical oxidation of dimethyl sulfide, which comes from marine algae and salt marsh plants(2).

Methanesulfonic acid's production and use as a catalyst in esterification, alkylation, olefin polymerization, peroxidation reactions(1) and as a solvent(2) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that methanesulfonic acid is expected to have very mobility in soil(SRC). The pKa of methanesulfonic acid is -1.86(3), indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. Methanesulfonic acid is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 4.28X10-4 mm Hg at 25 °C(5). Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks(6) indicating that biodegradation is an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that methanesulfonic acid is not expected to adsorb to suspended solids and sediment(SRC). A pKa of -1.86(3) indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process(4). Methanesulfonic acid is miscible with water(5) and therefore bioconcentration in aquatic organisms is low(SRC). Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks(6) indicating that biodegradation is an important environmental fate process in water(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methanesulfonic acid, which has a measured vapor pressure of 4.28X10-4 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase methanesulfonic acid 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 58 days(SRC), calculated from its rate constant of 2.8X10-13 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Methanesulfonic acid does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

AEROBIC: Methanesulfonic acid, present at 100 mg/L, reached 100% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test(1).

The rate constant for the vapor-phase reaction of methanesulfonic acid with photochemically-produced hydroxyl radicals has been estimated as 2.8X10-13 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 58 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Methanesulfonic acid is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). Methanesulfonic acid does not contain chromophores that absorb at wavelengths >290 nm(2) and therefore is not expected to direct photolysis by sunlight(SRC).

Methanesulfonic acid is miscible with water(1) and therefore bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of methanesulfonic acid can be estimated to be 1(SRC). According to a classification scheme(2), this estimated Koc value suggests that methanesulfonic acid is expected to have very high mobility in soil. The pKa of methanesulfonic acid is -1.86(3), indicating that this compound will almost entirely exist in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4).

A pKa of -1.86(1) indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces or moist soil surfaces is not expected to be an important fate process(2). Methanesulfonic acid is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure of 4.28X10-4 mm Hg(3).

RAINWATER: Methanesulfonic acid was detected in rainwater ranging from 41.9 (July 1996) to 1325.8 (December 1996) neq/L (volume weighted monthly mean concentrations) collected at Amsterdam Island in the Southern Indian Ocean, sampled from December 1995 to February 1997(1).

ICE/SNOW: The methanesulfonate ion was found to be present at a mean concentration of 0.08 microequivalents/L and ranged between 0.006 and 0.28 microequivalents/L in Antarctic ice from Law Dome(1).

URBAN/SUBURBAN: Methanesulfonic acid concentration in air particle samples collected from atop an office building in Kobe City, Japan, 1 km distant from Osaka Bay(1).

Table: Concn (ng/cu m) in Urban Particles [Table#4992]

RURAL/REMOTE: Methanesulfonic acid had sub-micrometer-aerosol concentration peaks of approximately 0.47 and 0.4 mol/cu m in February and December, respectively, in the atmosphere at Cape Grim off of Australia in 1989(1). Methanesulfonic acid was found at the highest levels in atmospheric samples collected around noon and concentrated in the smaller size particles (0.25-2 um in diameter) at concentrations of 5.3, 5.5, and 15.7 ng/cu meter in samples taken from the Southern Bahamas, the Northern Bahamas, and the Sargasso Sea, respectively(2). Methanesulfonic acid was found in Germany at concentrations of 0.02 - 0.43 ug/cu m in atmospheric samples taken in October and November of 1978(3). Aerosol methanesulfonic acid was detected at six stations in the Pacific at mean concentrations of 0.097, 0.029, 0.044, 0.026, 0.021, and 0.024 ug/cu m(4). Aerosol methanesulfonic acid has been found at mean concentrations of 9.27X10-9 and 1.14X10-9 mol/cu m in July of 1985 and December of 1986 in the marine atmosphere of the British Isles(5).

RURAL/REMOTE: Methanesulfonic acid was detected in 62 out of 62 air samples collected from the UK to Antarctica between Mar 10, 1992 to Oct 1, 1993 at concentrations ranging from 1.72 to 362 ng/cu m, average 77 ng/cu m(1). Methanesulfonic acid was detected in 18 out of 18 air samples collected from the UK to the Falkland Islands between Mar 10, 1992 to Jan 11, 1992 at concentrations ranging from 1.72 to 39.7 ng/cu m, average 14.3 ng/cu m(1). Methanesulfonic acid was detected in 44 out of 44 air samples collected from areas south of the Falkland Islands between May 11, 1992 to Oct 1, 1993 at concentrations ranging from 1.94 to 362 ng/cu m, average 103 ng/cu m(1). Methanesulfonic acid was detected in 23 out of 23 air samples collected from the Halley Bay in the east Weddell Sea between Aug 12, 1992 to Oct 1, 1993 at concentrations ranging from 2.48 to 362 ng/cu m, average 136 ng/cu m(1). Methanesulfonic acid was detected in the upper limit of 39 samples collected from the Atlantic ocean between March 1987 to September 1988 at concentrations ranging from 3.9-8.5 ng/cu m(2). Methanesulfonic acid was detected in the upper limit of 4 samples collected from the English channel between April 1987 to September 1988 at concentrations ranging from 13.8-24.3 ng/cu m(2). Methanesulfonic acid was detected in the upper limit of 43 samples collected from the North Sea between April 1986 to April 1989 at concentrations ranging from 12.8 to 66.2 ng/cu m(2).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 8,084 workers (1,393 of these were female) were potentially exposed to methanesulfonic acid in the US(1). Occupational exposure to methane sulfonic acid may occur through inhalation and dermal contact with this compound at workplaces where methanesulfonic acid is produced or used. Monitoring data indicate that the general population may be exposed to methanesulfonic acid via inhalation of ambient air(SRC).

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Observe all federal, state, and local environmental regulations. Contact a licensed professional waste disposal service to dispose of this material. Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber.

UN3265, Class 8, Corrosive liquid, acidic, organic, n.o.s. (Methanesulfonic acid)[Sigma-Aldrich Material Safety Data Sheet for Methanesulfonic acid (CAS: 75-75-2). Available from, as of November 20, 2009: http://www.sigmaaldrich.com]

Methanesulfonic acid is shipped in tank trucks and in plastic 55-gal drums or smaller containers with polyethylene inserts.

The freight classification is Alkyl Sulfonic Acid, Liquid; 8 Corrosive Material, UN 2586, Chemical N01BN.