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SECTION 1. CHEMICAL IDENTIFICATION

CHEMINFO Record Number: 589
CCOHS Chemical Name: Chlorosulfonic acid

Synonyms:
CSA
Chlorosulfuric acid
Monochlorosulfuric acid
Sulfonic acid, monochloride
Sulfuric chlorohydrin
Chlorosulphuric acid
Chlorosulphonic acid
Monochlorosulfonic acid
Chlorohydrosulfurous acid
Sulfuric acid chlorohydrin
Chlorohydrated sulfuric acid
Acide chlorosulfurique

Chemical Name French: Acide chlorosulfonique
Chemical Name Spanish: Acido clorosulfúrico
CAS Registry Number: 7790-94-5
UN/NA Number(s): 1754
RTECS Number(s): FX5730000
EU EINECS/ELINCS Number: 232-234-6
Chemical Family: Halogenated inorganic acid / halogenated sulfuric acid / chlorinated inorganic acid / chlorinated sulfuric acid / chlorosulfuric acid / monochlorosulfuric acid
Molecular Formula: Cl-H-O3-S
Structural Formula: Cl-S(=O)2-OH

SECTION 2. DESCRIPTION

Appearance and Odour:
Clear, colourless to straw-coloured liquid with a sharp, pungent, acrid, choking odor.(1,2,10,13) Fumes very strongly releasing heavy white vapours and dense white clouds of hydrochloric acid and sulfuric acid mists on exposure to air.(1,8,13) Highly hygroscopic (absorbs moisture from the air).(1,5)

Odour Threshold:
Not available for chlorosulfonic acid. Odour threshold for products of reaction with moisture: hydrogen chloride: 1-5 ppm (9); sulfuric acid: 0.25 ppm (cited as 1 mg/m3).(12)

Warning Properties:
Information not available for evaluation.

Composition/Purity:
Chlorosulfonic acid is commercially available in 98-99.5% purity, with minor impurities of related materials such as sulfuric acid (0.2-2%), sulfur trioxide (0-2%) and hydrochloric acid (0-0.5%).(1,2) Iron is typically present in 5-50 ppm concentrations.(2) A product low in iron (5-25 ppm) is normally required for most applications.(1)

Uses and Occurrences:
Chlorosulfonic acid is used mainly in organic synthesis as a sulfating, sulfonating, chlorosulfonating or condensing agent. Its main applications are as an intermediate in the production of synthetic detergents (surfactants) (e.g. sodium lauryl sulfate), pharmaceuticals (e.g. sulfonamide antibacterials), sulfonyl dyes (e.g. monoazo dyes) and condensation azo pigments, agrochemicals (herbicides and acaricides), artificial sweeteners (e.g. saccharin), sulfonyl polymers, ion-exchange resins, plasticizers, disinfectants (e.g. chloramines), and sulfonyl azides and hydrazides. It is also used as a catalyst in certain chemical reactions (in esterification and alkylation reactions, and in the preparation of alkyl halides and unsaturated ketones); in the preparation of tanning agents, textile and paper specialties, fluorocarbons, rubber and plastic release agents; as a vulcanization aid for isoolefin copolymers; as a source of anhydrous hydrogen chloride; and as a separating agent for mixtures of sulfur dioxide and chlorine. Chlorosulfonic acid mixed with sulfur trioxide, known as FS, is used as a chemical smoke in warfare.(2,13)


SECTION 3. HAZARDS IDENTIFICATION

EMERGENCY OVERVIEW:
Clear, colourless to straw-coloured liquid with a sharp, pungent, acrid, choking odour. Fumes very strongly releasing heavy white vapours and dense white clouds of hydrochloric acid and sulfuric acid mists on exposure to air Highly hygroscopic. Will not burn. Can decompose at high temperatures forming very toxic and corrosive hydrogen chloride, chlorine, sulfur dioxide, sulfuric acid and sulfuryl chloride. Releases extremely flammable hydrogen gas on contact with many metals, particularly in powered form. STRONG OXIDIZER. Contact with combustible materials may cause a fire. DANGEROUSLY REACTIVE. Reacts violently or explosively with water (including water vapour in air) to produce very toxic and corrosive hydrogen chloride gas and very toxic and corrosive sulfuric acid and heat. Highly reactive. May react violently or explosively with many organic and inorganic chemicals. VERY TOXIC. May be fatal if inhaled, absorbed through the skin or swallowed. The mixture of vapours and mists resulting from the reaction with water can cause severe irritation of the nose, sore throat, coughing, shortness of breath and difficulty breathing and burns to the nose and throat. Causes lung injury-effects may be delayed. CORROSIVE to the eyes, skin and respiratory tract. Causes severe burns. May cause permanent eye injury, including blindness. May cause permanent scarring.



POTENTIAL HEALTH EFFECTS

Effects of Short-Term (Acute) Exposure

Inhalation:
Chlorosulfonic acid is an extremely strong, reactive acid that is normally produced, shipped, stored and used in pure, undiluted form. It reacts violently with water (including water vapour in air) to release sulfuric acid and hydrochloric acid. This reaction results in a mixture of vapours and mists of all three of these corrosive and very toxic acids, which can appear as a dense acid mist.(5)
Exposure can cause severe irritation of the nose, sore throat, coughing, shortness of breath and difficulty breathing. Burns to the nose and throat and a potentially fatal accumulation of fluid in the lungs (pulmonary edema) could occur. Symptoms of pulmonary edema (chest pain and shortness of breath) can be delayed for up to 24 or 48 hours after exposure. Permanent lung damage could result from a severe short-term exposure. These effects have been observed in animal studies, but no human case reports were located.

Skin Contact:
Chlorosulfonic acid is corrosive. Corrosive materials are capable of producing severe burns, blisters, ulcers and permanent scarring, depending on the concentration of the solution and the duration of contact. Any skin contact will also involve significant inhalation exposure.
Chlorosulfonic acid very toxic following skin contact, based on an animal toxicity value. There is no human information available.

Eye Contact:
Chlorosulfonic acid is corrosive. Corrosive materials are capable of producing severe eye burns, and permanent injury, including blindness, depending on the concentration of the solutions and duration of contact. Any eye contact may also involve significant inhalation exposure.
There is a report of a person accidentally dropping chlorosulfonic acid into water with the resulting explosion spraying into his face. He immediately rinsed his eyes thoroughly with water, which probably saved his sight. Burns to the eyes were healing well with vision returning to normal after 2 weeks.(3)

Ingestion:
Chlorosulfonic acid is toxic if ingested, based on an animal toxicity value. It is corrosive and can cause burns to the lips, tongue, throat and stomach, abdominal pain, nausea, vomiting, diarrhea and death. It reacts readily and exothermically with moisture to release hydrochloric acid and sulfuric acid, which are also very toxic and corrosive. Ingestion is not a typical route of occupational exposure.

Effects of Long-Term (Chronic) Exposure

There is no specific information for chlorosulfonic acid. However, repeated or prolonged exposure to strong acids, like chlorosulfonic acid, can cause signs of chronic respiratory and skin irritation. Dental erosion has also been reported.

Lungs/Respiratory System:
Repeated or prolonged exposure to strong acids, like chlorosulfonic acid, may cause severe irritation of the lungs, and development of bronchitis with cough, phlegm and/or shortness of breath.(5)
Chlorosulfonic acid reacts violently with moisture in air to release hydrochloric acid and sulfuric acid resulting in a mixture of vapours and mists of all 3 of these compounds. Long-term inhalation exposure to these acids could cause symptoms of chronic respiratory irritation like bronchial hyperreactivity.

Skin:
Repeated exposure to low concentrations of acid solutions, mist or vapour can cause redness, swelling and pain (dermatitis).

DENTAL EROSION:
Repeated exposures to sulfuric acid and hydrochloric acid mists or aerosols can cause dental erosion. Similar effects would be expected following long-term exposure to airborne chlorosulfonic acid.

Carcinogenicity:

There is no specific information for chlorosulfonic acid. However, chlorosulfonic acid reacts violently with moisture in air to release hydrochloric acid and sulfuric acid resulting in a mixture of vapours and mists of all 3 of these compounds.

The International Agency for Research on Cancer (IARC) has not evaluated the carcinogenicity of this chemical.

IARC has concluded there is sufficient evidence that occupational exposure to strong inorganic acid mists containing sulfuric acid is carcinogenic to humans (Group 1). This IARC designation does not apply to sulfuric acid alone. IARC has determined that there is inadequate evidence for carcinogenicity of hydrogen chloride in humans (Group 3).(19)

The American Conference of Governmental Industrial Hygienists (ACGIH) has no listing for this chemical.

ACGIH has designated strong inorganic acid mists containing sulfuric acid as A2 (suspected human carcinogen). ACGIH has designated hydrochloric acid as A4 (not classifiable as a human carcinogen).

The US National Toxicology Program (NTP) has not listed this chemical in its report on carcinogens.

NTP has listed strong inorganic acid mists containing sulfuric acid as a known human carcinogen.(20) NTP has not listed hydrochloric acid in its report on carcinogens.

Teratogenicity and Embryotoxicity:
There is no human or animal information available.

Reproductive Toxicity:
There is no human or animal information available.

Mutagenicity:
There is no information available.

Toxicologically Synergistic Materials:
There is no information available.

Potential for Accumulation:
Probably does not accumulate.


SECTION 4. FIRST AID MEASURES

Inhalation:
This chemical is very toxic. Take proper precautions to ensure your own safety before attempting rescue (e.g. wear appropriate protective equipment, use the "buddy" system). Remove source of contamination or move victim to fresh air. If breathing is difficult, trained personnel should administer emergency oxygen. DO NOT allow victim to move about unnecessarily. Symptoms of pulmonary edema can be delayed up to 48 hours after exposure. Avoid mouth-to-mouth contact by using mouth guards or shields. Quickly transport victim to an emergency care facility.

Skin Contact:
Avoid direct contact. Wear chemical protective clothing, if necessary. As quickly as possible, remove contaminated clothing, shoes and leather goods (e.g. watchbands, belts). Quickly and gently blot or brush away excess chemical. Immediately flush with lukewarm, gently flowing water for at least 30 minutes. DO NOT INTERRUPT FLUSHING. If necessary, and it can be done safely, continue flushing during transport to emergency care facility. Quickly transport victim to an emergency care facility. Double bag, seal, label and leave contaminated clothing, shoes and leather goods at the scene for safe disposal. Keep contaminated clothing under water in a closed container until it can be safely discarded. Note: Corrosive chemicals will form in the water. NOTE: Any skin contact will also involve significant inhalation exposure.

Eye Contact:
Avoid direct contact. Wear chemical protective gloves, if necessary. Quickly and gently blot or brush chemical off the face. Immediately flush the contaminated eye(s) with lukewarm, gently flowing water for at least 30 minutes, while holding the eyelid(s) open. If a contact lens is present, DO NOT delay irrigation or attempt to remove the lens. Neutral saline solution may be used as soon as it is available. DO NOT INTERRUPT FLUSHING. If necessary, continue flushing during transport to emergency care facility. Take care not to rinse contaminated water into the unaffected eye or onto the face. Quickly transport victim to an emergency care facility. NOTE: Any eye contact may involve significant inhalation exposure.

Ingestion:
NEVER give anything by mouth if victim is rapidly losing consciousness, or is unconscious or convulsing. Have victim rinse mouth thoroughly with water. DO NOT INDUCE VOMITING. If vomiting occurs naturally, repeat administration of water. Quickly transport victim to an emergency care facility.

First Aid Comments:
Provide general supportive measures (comfort, warmth, rest).
Consult a doctor and/or the nearest Poison Control Centre for all exposures.
Some first aid procedures recommended above require advanced first aid training. Protocols for undertaking advanced procedures must be developed in consultation with a doctor and routinely reviewed.
All first aid procedures should be periodically reviewed by a doctor familiar with the material and its conditions of use in the workplace.



SECTION 5. FIRE FIGHTING MEASURES

Flash Point:
Not combustible (does not burn).(7)

Lower Flammable (Explosive) Limit (LFL/LEL):
Not applicable

Upper Flammable (Explosive) Limit (UFL/UEL):
Not applicable

Autoignition (Ignition) Temperature:
Not applicable

Sensitivity to Mechanical Impact:
Probably not sensitive. Stable material.

Sensitivity to Static Charge:
Chlorosulfonic acid will not accumulate static charge since it has a very high electrical conductivity and dielectric constant.(1,13) Since it does not burn, chlorosulfonic acid will not be ignited by a static discharge.

Electrical Conductivity:
2-3 x 10(10) pS/m (1,13)

Flammable Properties:

Specific Hazards Arising from the Chemical:
Explosive decomposition may occur under fire conditions and closed containers may rupture violently due to rapid decomposition, if exposed to fire or excessive heat for a sufficient period of time. Chlorosulfonic acid decomposes rapidly in a fire to produce hydrogen chloride, chlorine, sulfur dioxide and sulfuric acid.(7) It begins to decompose at or above its boiling point to sulfuryl chloride and sulfuric acid. At higher temperatures (above 190 deg C), it decomposes to sulfur dioxide, chlorine and sulfuric acid.(2) Prolonged heating results in the formation of hydrogen chloride, chlorine, sulfur dioxide, sulfuric acid, sulfuryl chloride, pyrosulfuryl chloride, pyrosulfuryl dichloride, and pyrosulfuric acid.(1,2,13)

Extinguishing Media:
Chlorosulfonic acid does not burn. Use extinguishing agents compatible with chlorosulfonic acid and appropriate for surrounding fire. Use carbon dioxide, dry chemical powder or appropriate foam.(7) Foam manufacturers should be consulted for recommendations regarding types of foams and application rates. Water spray may be used only to keep non-leaking, fire-exposed containers cool.

Extinguishing Media to be Avoided:
DO NOT use water or water-based extinguishers since chlorosulfonic acid reacts violently or explosively upon contact with water generating heat, hydrogen chloride fumes, hydrochloric acid, and sulfuric acid mists and steam.(7,10,13)

Fire Fighting Instructions:
Extreme caution is required in a fire situation. Evacuate area and fight fire from a protected location or maximum possible distance. Approach fire from upwind to avoid hazardous decomposition products, such as hydrogen chloride, chlorine, sulfur dioxide and sulfuric acid. Wear full protective gear if exposure is possible.
If possible, isolate materials not involved in the fire, if this can be done without risk, and protect personnel. If chlorosulfonic acid is not involved in the fire, move containers from the fire area only if they have not been exposed to heat. Use extreme caution since decomposition can occur under fire conditions and heat may rupture containers. Otherwise, apply water from as far a distance as possible, in flooding quantities as a spray or fog streams to keep fire-exposed containers or equipment cool and absorb heat, until well after the fire is out. No part of a container should be subjected to a temperature higher than 49 deg C (120 deg F). Water spray or fog may also be used to knock down irritating/toxic combustion products which may be produced in a fire. Dike fire control water for appropriate disposal to prevent run-off. Avoid use of water on non-involved material wherever possible. DO NOT ALLOW water to come into contact with the chlorosulfonic acid, since a violent or explosive reaction can occur with the generation of heat and formation of large quantities of dense, white, acid fumes.
Chlorosulfonic acid is a strong oxidizing agent. Remove all flammable and combustible materials from the vicinity, especially oil and grease.
Stay away from ends of tanks, but realize that flying material from ruptured tanks may travel in any direction. Withdraw immediately in case of rising sound from venting safety device or any discolouration of tanks due to fire. In an advanced or massive fire, the area should be evacuated. Use unmanned hoseholders or monitor nozzles.
Containers should not be approached directly after they have been involved in a fire or heated by exposure, until they have been completely cooled down. Clean-up or salvage operations should not be attempted until the chlorosulfonic is cooled. After the fire has been extinguished, corrosive and toxic atmospheres may linger. Before entering such an area, especially confined areas, check the atmosphere with an appropriate monitoring device while wearing a full protective gear.
Containers should be opened and inspected. If the contents are damaged or the material is damp, the material should be chemically treated, if allowable, to a non-oxidizing material for safe disposal. Broken containers should not be re-closed. Any spilled material from burned or broken containers should be assumed to be contaminated and neutralized to non-oxidizing material for safe disposal. Caution must be taken to make sure that water does not contact material during this process.(10)

Protection of Fire Fighters:
Chlorosulfonic acid and its decomposition products (hydrogen chloride, chlorine, sulfur dioxide and sulfuric acid) are corrosive and hazardous to health. Do not enter without wearing specialized equipment suitable for the situation. Firefighter's normal protective clothing (Bunker Gear) will not provide adequate protection. A full-body encapsulating chemical protective suit with positive pressure self-contained breathing apparatus (NIOSH approved or equivalent) may be necessary.



NATIONAL FIRE PROTECTION ASSOCIATION (NFPA) HAZARD IDENTIFICATION

NFPA - Health: 4 - Very short exposure could cause death or major residual injury.
NFPA - Flammability: 0 - Will not burn under typical fire conditions.
NFPA - Instability: 2 - Undergoes violent chemical change at elevated temperatures and pressures, or reacts violently with water, or may form explosive mixtures with water.
NFPA - Specific Hazards: OXIDIZING MATERIAL AND WATER REACTIVE

SECTION 9. PHYSICAL AND CHEMICAL PROPERTIES

Molecular Weight: 116.53

Conversion Factor:
1 ppm = 4.76 mg/m3; 1 mg/m3 = 0.21 ppm at 25 deg C (calculated)

Physical State: Liquid
Melting Point: -81 to -80 deg C (-113.8 to -112 deg F) (1,13)
Boiling Point: 151-152 deg C (303.8-305.6 deg F) (decomposes) (1,13); also reported as 158 deg C (316.4 deg F) (21,22)
Relative Density (Specific Gravity): 1.753 at 20 deg C (water = 1) (1,2)
Solubility in Water: Reacts violently or explosively on contact with water.(1,2,13)
Solubility in Other Liquids: Soluble in dichloromethane, chloroform, 1,2-dichloroethane, 1,1,2,2,-tetrachloroethane, acetic acid, acetic anhydride, trifluoroacetic acid, trifluoroacetic anhydride, nitrobenzene, sulfuryl chloride and liquid sulfur dioxide; sparingly soluble in carbon tetrachloride and carbon disulfide.(1,2,13) Chlorosulfonic acid reacts with alcohols, ketones, ethers, and dimethyl sulfoxide.(1,13)
Coefficient of Oil/Water Distribution (Partition Coefficient): Not applicable. Chlorosulfonic acid reacts violently or explosively on contact with water.(21)
pH Value: Less than 1 at 20 deg C* (23)
Acidity: Strong acid.(1,2,13)
Dissociation Constant: Not available.*
Viscosity-Dynamic: 3 mPa.s (3 centipoises) at 15.6 deg C (1,13)
Surface Tension: Not available
Vapour Density: 4.02 (air = 1) (calculated)
Vapour Pressure: 0.100 kPa (0.75 mm Hg) at 20 deg C (21)
Saturation Vapour Concentration: 1000 ppm (0.10%) at 20 deg C (calculated)
Evaporation Rate: The evaporation rate is not available. However, chlorosulfonic acid reacts readily with moisture in the air to form hydrochloric and sulfuric acid vapours and mists.
Henry's Law Constant: Not applicable. Chlorosulfonic acid reacts violently or explosively on contact with water.(21)

Other Physical Properties:
DIELECTRIC CONSTANT: 60 ± 10 at 15 deg C (24)

Physical Properties Comments:
Chlorosulfonic acid is difficult to purify, because of its instability at the boiling point, and has frequently been used in an impure state for experimental determinations.(1,2) It is also difficult to keep the chlorosulfonic acid anhydrous (dry) for measurements.(24)

*The dissociation constant and pH of pure chlorosulfonic acid are difficult to measure since it decomposes in water to form strongly acidic solutions of hydrochloric and sulfuric acids.


SECTION 10. STABILITY AND REACTIVITY

Stability:
Chlorosulfonic acid is unstable. Chlorosulfonic acid vapours or fumes react with moisture in the air to form heavy white vapours and dense, pungent, corrosive clouds of hydrochloric acid and sulfuric acid mists.(2,13) Contact with water can be violent, producing heat, and hydrochloric and sulfuric acids.(1,2,13) Chlorosulfonic acid is stable if kept dry.

Possibility of Hazardous Reactions:
Chlorosulfonic acid is a strong oxidizing agent.(7,8,17) It can ignite oxidizable or combustible materials upon contact.(17) Hydrogen chloride gas is formed on contact with moisture in the air. Hydrogen chloride then absorbs moisture to form corrosive hydrochloric acid mist.

Incompatibility - Materials to Avoid:

NOTE: Chemical reactions that could result in a hazardous situation (e.g. generation of flammable or toxic chemicals, fire or detonation) are listed here. Many of these reactions can be done safely if specific control measures (e.g. cooling of the reaction) are in place. Although not intended to be complete, an overview of important reactions involving common chemicals is provided to assist in the development of safe work practices.


Chlorosulfonic acid is a strong oxidizing agent and is capable of reacting violently and/or explosively with many substances. For reviews of chlorosulfonic acid reactivity, consult references 7, 8 and 25. Some of the substances chlorosulfonic acid can react with include:
WATER - reacts violently or explosively with water to produce heat and hydrochloric and sulfuric acids.(1,2,13)
METALS and METAL POWDERS - can produce extremely flammable hydrogen gas on contact, especially if moist.(1,7,8,13)
COMBUSTIBLE MATERIALS (e.g. wood, paper, textiles, oil, grease) - may cause fire upon contact.(7,8,17)
ORGANIC COMPOUNDS (e.g. carboxylic acids and anhydrides, acetates, alcohols, aldehydes, ketones, ethers, glycols, nitriles, nitrogen-containing bases, nitro compounds and unsaturated hydrocarbons) - react vigorously, violently or explosively.(7,8)
INORGANIC COMPOUNDS (e.g. nitrates, chlorates, carbides, cyanides, fulminates, picrates and sulfides) - react violently or explosively with the generation of heat.(7,17),
INORGANIC ACIDS (e.g. hydrochloric acid, hydrofluoric acid or nitric acid) or HYDROGEN PEROXIDE - react vigorously or violently.(7,10,26)
STRONG BASES (e.g. sodium hydroxide, potassium hydroxide, or ammonium hydroxide) - reaction may be violent.
SULFURIC ACID (96-98%) - hydrogen chloride gas is rapidly formed when chlorosulfonic acid reacts with the water present in the sulfuric acid (2-4%).(7,25)
PHOSPHORUS - explosive reaction with white or yellow phosphorus above 25-30 deg C.(2,25,26)
SILVER NITRATE - interaction is violent, with nitrosulfuric acid being formed.(25)
HYDROCARBONS (e.g. heptane or hexane) - react vigorously to generate large amounts of hydrogen chloride, sulfur dioxide and other gases.(7,24)
DIPHENYL ETHER - vigorous interaction above 40 deg C.(25,26)
PHOSPHORUS TRIBROMIDE or PHOSPHORUS TRIIODIDE - react vigorously.(25)

Hazardous Decomposition Products:
Chlorosulfonic acid can react violently with water producing heat and large quantities of dense white fumes of hydrochloric acid and sulfuric acid.(1,13)

Conditions to Avoid:
Moisture, open flames, sparks, high temperatures.

Corrosivity to Metals:
Chlorosulfonic acid is corrosive to many metals at room temperature, especially if water is present. These include some stainless steels (e.g. types 301, 302, 304, 17 4PH and 400 series (wet or dry)), aluminum alloys (e.g. types 3003 (wet or dry) and Cast B-356), carbon steel (types 1010 and 1020 (wet or dry), 1075 (wet)), cast iron (wet), nickel cast iron, ductile cast iron (wet), the nickel-base alloy, Incoloy, and most non-ferrous metals, such as copper, bronze, (unspecified), silicon bronze, aluminum bronze, brass, cartridge brass, naval brass and lead.(22,27,28) Pure chlorosulfonic acid (98-100%) and mixtures are not corrosive to nickel, the nickel-base alloys, Monel, Inconel and Hastelloy B and C (in the presence and absence of water), tantalum and titanium.(22,27,28) Pure aluminum metal, pure iron, high silicon cast iron, low alloy steel, mild steel, types 303, 304, 316 and 317 stainless steels (up to 125 deg C and Carpenter 20Cb (up to 50 deg C) are resistant to pure chlorosulfonic acid at room temperature if water is excluded.(22,27,28) One source reports that chlorosulfonic is not corrosive to carbon steel (alloy unspecified) in the absence of water.(28)

Corrosivity to Non-Metals:
Chlorosulfonic acid attacks plastics, such as polyvinylidene chloride (Saran), chlorinated polyvinyl chloride (CPVC), polyvinyl chloride (PVC) (above 20 deg C), polypropylene, nylon, acrylonitrile-butadiene-styrene ((ABS), polyurethane (rigid), polybutylene terephthalate, polyethylene terephthalate, high-density polyethylene (HDPE), ultra high molecular weight polyethylene (UHMPE), cross-linked polyethylene (XLPE), polyphenylene oxide (Noryl), thermoset bisphenol-A fumarate and isophthalic acid polyesters, thermoset vinyl ester, thermoset epoxy and ethylene vinyl acetate (EVA) (28,29); and elastomers, such as nitrile buna N (NBR), chloroprene, ethylene-propylene-diene, Viton A, styrene-butadiene (SBR), polyurethane, butyl rubber (isobutylene isoprene), isoprene, natural rubber, neoprene, chlorosulfonated polyethylene (CSM), fluorosilicone, chlorinated polyethylene (CM), flexible polyvinyl chloride (PVC) and low-density polyethylene (LDPE).(28,30) Chlorosulfonic acid does not attack plastics, such as Teflon, other fluorocarbons, like ethylene chlorotrifluoro ethylene (Halar) and ethylene tetrafluoroethylene (Tefzel) and polyetherether ketone (PEEK) at room temperature, and polyvinyl chloride (PVC) below 20 deg C (28,29); and elastomers, such as Teflon and other fluorocarbons, Chemraz and Kalrez at room temperature.(28,30)


SECTION 11. TOXICOLOGICAL INFORMATION

Chlorosulfonic acid reacts violently with water to produce hydrochloric and sulfuric acids. It reacts with moisture in the air to produce a combination of hydrochloric and sulfuric acid mists plus their vapours. The health hazards of hydrochloric acid and/or sulfuric acid are summarized in the CHEMINFO reviews of these chemicals.

LC50 (rat): 230 mg/m3 (4-hour exposure; aerosol); cited as 926 mg/m3 (1-hour exposure; aerosol) (4)
LC50 (mouse): 37 mg/m3 (4-hour exposure); cited as 52 mg/m3 (2-hour exposure) (5, unconfirmed)
LC50 (rat): 38.5 mg/m3 (4-hour exposure) (5, unconfirmed)

LD50 (oral, rat): 50-400 mg/kg (4)

LD50 (dermal, guinea pig): 90-180 mg/kg (cited as 0.05-0.10 cc/kg) (4)

Skin Irritation:

Chlorosulfonic acid is corrosive to the skin.

Application of 0.01-1.0 mL/kg of undiluted chlorosulfonic acid for an unspecified time caused moderate swelling, tissue death (necrosis) and scarring in guinea pigs.(4)

Effects of Short-Term (Acute) Exposure:

Chlorosulfonic aerosols are corrosive to the respiratory tract.

Inhalation:
Rats were given a single exposure to 1765, 2768 or 5864 mg/m3 chlorosulfonic acid aerosol (nose-only). At 1765 mg/m3, 8/20 animals died, at 2768 mg/m3 13/20 died and at 5864 mg/m3 9/10 died. Symptoms of sensory irritation (slowed and interrupted breathing), pulmonary irritation (gasping, laboured breathing), red-stained eyes and signs of central nervous system (CNS) depression (loss of muscular coordination, extreme exhaustion) increased in severity and incidence with concentration. These symptoms persisted over 2 weeks of observation with the persistence of signs of pulmonary irritation indicating significant irritation of the lower respiratory tract. The signs of CNS depression were considered to be secondary to the reduction of oxygen supply caused by respiratory distress.(4) Rats were exposed to 70, 282, 563, 1500, 2250 or 3400 mg/m3 aerosol for one hour and observed for 2 weeks. Signs of respiratory irritation were noted at 563 mg/m3 and higher. All males died at 1500 mg/m3 and higher, while 4/5 females died at 1500 mg/m3 and all animals died at higher concentrations. No animals died at 563 mg/m3 and lower. Concentrations of 1500 mg/m3 and higher produced eye irritation, degeneration and inflammation of the trachea, atrophy of the spleen and thymus and enlargement of the liver. Death was believed to be caused by airway obstruction from damage to the trachea.(18)


SECTION 16. OTHER INFORMATION

Selected Bibliography:
(1) Maas, J, et al. Chlorosulfuric acid. In: Ullmann's encyclopedia of industrial chemistry. 7th ed. John Wiley and Sons, 2005. Available at: <www.mrw.interscience.wiley.com/ueic/ueic_search_fs.html> {Subscription required}
(2) Cremlyn, R.J. Chlorosulfonic acid: a versatile reagent. The Royal Society of Chemistry (RS.C), 2002
(3) Grant, W.M., et al. Toxicology of the Eye. 4th ed. Charles C. Thomas, 1993. p. 383
(4) Initial submission: letter from Eastman Kodak Co. to USEPA regarding toxicity studies of chlorosulfuric acid with attachments and cover letter dated 092492. Eastman Kodak. Date produced: Sept. 1992. EPA/OTS 88-920008908. NTIS/OTS0570953.
(5) Kapias, T., et al. Spill behaviour using REACTPOOL. Part 1. Results for accidental releases of chlorosulphonic acid (HSO(3)Cl). Journal of Hazardous Materials. Vol. 81, no. 1-2 (Jan. 2001). p. 19-30
(6) Forsberg, K., et al. Quick selection guide to chemical protective clothing. 4th edition. Van Nostrand Reinhold, 2003.
(7) Fire protection guide to hazardous materials. 13th ed. Edited by A.B. Spencer, et al. National Fire Protection Association, 2002. NFPA 49; NFPA 491 (chlorosulfuric acid)
(8) Properties and essential information for safe handling and use of chlorosulfonic acid: chemical safety data sheet SD-33. Manufacturing Chemists Association, Aug. 1968
(9) Enviro technical information for problem spills (TIPS). Hydrogen chloride/hydrochloric acid. Environment Canada, 1984
(10) Technical Services Branch, Environmental Protection Services, Environment Canada. Chlorosulfonic acid. In: Manual for spills of hazardous materials. Environment Canada, Mar. 1984
(11) Braley, G.K. Several remedies for the treatment of spillages of liquid hazardous chemicals. Imperial Chemical Industries Limited, n.d. p. 103-108
(12) Ruth, J.H. Odor thresholds and irritation levels of several chemical substances: a review. American Industrial Hygiene Association Journal. Vol. 47 (Mar. 1986). p. A-150
(13) McDonald, C. E. Chlorosulfuric acid. In: Kirk-Othmer encyclopedia of chemical technology. John Wiley and Sons, 2005. Available at: <www.mrw.interscience.wiley.com/kirk/kirk_search_fs.html> {Subscription required}
(14-old) Workplace environmental exposure level guide. AIHA Journal. Vol. 56, no. 2, 1995. p. 202
(15-old) Emergency response planning guidelines. AIHA Journal. Vol. 56, no. 3, 1995. p. 297
(16) European Economic Community. Commission Directive 93/72/EEC. Sept. 1, 1993
(17) Emergency action guide for chlorosulfonic acid. Association of American Railroads, Jan. 1988
(18) Initial submission: acute inhalation toxicity study of chlorosulfonic acid in rats with cover letter dated 061592. Rohm and Haas Co. Date produced: Oct. 1986. EPA/OTS 88-920003964. NTIS/OTS 0570953.
(19) International Agency for Research on Cancer (IARC). IARC Monographs on the evaluation of carcinogenic risks to humans. Vol. 54. Occupational exposures to mists and vapours from strong inorganic acids, and other industrial chemicals. World Health Organization, 1992. p. 41-130, 189-211
(20) Report on Carcinogens. 11th ed. US Department of Health and Human Services, Public Health Service, National Toxicology Program
(21) Syracuse Research Corporation. Environmental Fate Database: CHEMFATE Chemical Search. Last updated: Mar. 25, 2005. Available at: <www.syrres.com/esc/chemfate.htm>
(22) Chlorosulfonic acid. In: Handbook of corrosion data. 2nd ed. Edited by B. D. Craig, et al. ASM International, 1995. p. 289-291
(23) European Chemicals Bureau. Chlorosulfuric acid. In: IUCLID Dataset. Substance ID: 7790-94-5. European Commission, 2000. Available at: <http://ecb.jrc.it/IUCLID-Data-Sheet/7790945.pdf>
(24) Gillespie, R. J., et al. The "Force" method of determining the static dielectric constant of conducting liquids with particular reference to sulphuric, nitric and chlorosulphonic acids. Transactions of the Faraday Society. Vol. 54 (1958). p. 1846-1854
(25) Bretherick's reactive chemical hazards database. [CD-ROM]. 6th ed. Version 3.0. Edited by P.G. Urben. Butterworth-Heinemann Ltd., 1999
(26) Armour, M.-A. Chlorosulfonic acid. In: Hazardous laboratory chemicals disposal guide. 3rd ed. Lewis Publishers, 2003. p. 126-127
(27) Pruett, K.M. Chemical resistance guide to metals and alloys: a guide to chemical resistance of metals and alloys. Compass Publications, 1995. p. 86-97
(28) Schweitzer, P.A. Corrosion resistance tables: metals, nonmetals, coatings, mortars, plastics, elastomers and linings, and fabrics. 4th ed. Part A, A-D. Marcel Dekker, Inc., 1995. p. 785-788
(29) Pruett, K.M. Chemical resistance guide for plastics: a guide to chemical resistance of engineering thermoplastics, fluoroplastics, fibers and thermoset resins. Compass Publications, 2000. p. 110-121
(30) Pruett, K.M. Chemical resistance guide for elastomers II: a guide to chemical resistance of rubber and elastomeric compounds. Compass Publications, 1994. p. C-86 to C-91

Information on chemicals reviewed in the CHEMINFO database is drawn from a number of publicly available sources. A list of general references used to compile CHEMINFO records is available in the database Help.


Review/Preparation Date: 2007-05-08



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