Carbon disulfide (CS₂) is a colourless, volatile liquid often used as a building block in organic chemistry and as a non-polar solvent in industrial and chemical applications. Pure carbon disulfide has a chloroform-like odour, while its impure form can contain unpleasant-smelling contaminants such as carbonyl sulfide.
This liquid evapourates easily at room temperature, and its vapour is more than twice as dense as air. It is highly flammable and can form explosive mixtures in air. Naturally, small amounts of carbon disulfide are released from volcanic eruptions and marsh gases. Industrially, it is produced by reacting carbon and sulfur at very high temperatures.
What is Carbon Disulfide used for?
Carbon disulfide has had a wide range of industrial applications:
Rayon & Cellophane: One of its major uses is in the manufacture of regenerated cellulose rayon and cellophane via the viscose process.
Carbon Tetrachloride Production: It serves as a feedstock for carbon tetrachloride synthesis.
Preservative Applications: Historically, it has been used to protect fresh fruit during transport from insect and fungal damage.
Rubber & Resins: It plays a role in vulcanisation and is used to produce rubber accessories, resins, xanthates, thiocyanates, and adhesives.
Other Industrial Uses: Includes solvent applications, vinyl chloride polymerisation inhibition, petroleum well cleaning, electroplating, and wastewater treatment.
Agriculture: Previously used as a fumigant for stored grain pests and for treating botfly larvae in horses and ectoparasites in swine. However, its use as a grain fumigant in the U.S. was voluntarily discontinued after 1985.
Carbon disulfide is used in the vulcanisation of rubber, enhancing strength and flexibility, and in the manufacture of rubber accessories such as engine belts.
Sources & Routes of Exposure
Source of Exposure
The main risk of exposure to carbon disulfide is occupational. Workers in industries that use it are most likely to be exposed. Industrial emissions mainly release it into the air, potentially affecting people nearby. Exposure can occur through:
Inhalation of contaminated air
Consumption of contaminated water or food
Skin contact with soil, water, or substances containing the chemical
Additionally, carbon disulfide is released naturally from volcanoes and marshes in small amounts.
Routes of Exposure
The primary ways humans can be exposed include:
Inhalation
Ingestion
Skin contact
Health Effects
Acute Effects
Large ingestions of ethylene glycol can result in three distinct stages of toxicity:
In animal models (rats, mice, rabbits, guinea pigs), ethylene glycol has shown moderate acute toxicity via inhalation or dermal exposure and low to moderate toxicity through ingestion.
Chronic Effects
Long-term exposure, particularly in occupational settings, has shown serious health impacts:
Neurological: Behavioural changes, reduced nerve function, neuropathy, and motor deficits
Cardiovascular: Some studies link it to increased coronary heart disease and angina, although results are affected by confounding factors
Ocular & Dermatological: Chronic exposure may cause eye issues and skin lesions (e.g. blisters, eczema)
Systemic: Animal studies show effects on the central nervous system (CNS), liver, blood, and kidneys
The U.S. EPA has established exposure guidelines:
Reference Concentration (RfC): 0.7 mg/m³ (based on neurological effects in humans)
Reference Dose (RfD): 0.1 mg/kg/day (based on foetal malformations in animal studies)
Reproductive & Developmental Effects
In workplace settings, carbon disulfide exposure has been linked to:
Men: Decreased sperm count and libido
Women: Menstrual disturbances
Animal studies report developmental issues like
Skeletal and visceral deformities
Embryotoxicity
Behavioural and functional abnormalities
Carbon disulfide and its by-products can cross the placenta and reach foetal organs such as the brain, liver, and eyes.
Cancer Risk
A study noted a possible increase in lymphatic leukaemia among workers exposed to carbon disulfide and other chemicals. However, due to numerous confounding factors, the results are inconclusive. The EPA has not classified carbon disulfide as a human carcinogen.
Safety
First Aid Measures
Eye Contact:
If carbon disulfide comes into contact with the eyes, remove contact lenses if present, then flush eyes with running water for at least 15 minutes, keeping eyelids open. Cold water may be used. Avoid using eye ointments. Seek immediate medical attention.
Skin Contact:
Immediately rinse affected skin with plenty of water. Wash gently and thoroughly using a non-abrasive soap, paying close attention to skin folds and creases. Apply an emollient to the irritated area. If irritation persists, seek medical advice. Be sure to wash contaminated clothing before reuse.
Serious Skin Contact:
Cleanse the affected area with a disinfectant soap, then apply an anti-bacterial cream. Seek medical assistance promptly.
Inhalation:
Move the affected individual to a well-ventilated area and allow them to rest. Seek immediate medical help.
Serious Inhalation:
Evacuate the person to a safe location right away. Loosen any tight clothing such as collars, belts, or waistbands. If breathing is difficult, administer oxygen. If the person is not breathing, begin mouth-to-mouth resuscitation. Immediate medical attention is required.
Ingestion:
Do not induce vomiting. Loosen tight clothing. If the individual is not breathing, begin mouth-to-mouth resuscitation. Call for emergency medical help immediately.
Fire Data
Carbon disulfide is highly flammable, especially in the presence of open flames, sparks, and oxidising agents. Though a liquid, it is flammable when dissolved or dispersed in water.
Small fires: Use dry chemical powder.
Large fires: Use alcohol-resistant foam, water spray, or fog.
Exposure Controls and Personal Protection
Exposure Controls
Good exhaust ventilation or local fume extraction should be in place to keep vapour concentrations below the recommended threshold limits. Emergency eyewash stations and safety showers should be easily accessible near workstations where carbon disulfide is used.
Personal Protective Equipment
When working with carbon disulfide, use the following PPE:
Splash goggles
Lab coat
Vapour respirator (certified/approved)
Protective gloves
In case of a large spill, additional PPE includes:
Full protective suit
Boots
Vapour respirator
Splash goggles
Gloves
Self-contained breathing apparatus (SCBA) to prevent inhalation of vapours
Note: Always consult a safety specialist or industrial hygienist before handling carbon disulfide. The PPE listed above may not be sufficient depending on specific working conditions.
Regulation
Exposure Limits
United States
The Occupational Safety and Health Administration (OSHA) permissible exposure limits (PELs) for carbon disulfide are 20 ppm as an 8-hour time-weighted average (TWA) concentration, 30 ppm as an acceptable peak concentration for 30-minutes, and 100 ppm as a maximum peak [29 CFR 1910.1000, Table Z-2].
The National Institute for Occupational Safety and Health (NIOSH) has established a recommended exposure limits (RELs) for carbon disulfide of 1 ppm (3 milligrams per cubic metre (mg/m3) as a TWA for up to an hour workday and a 40-hour workweek, and a 10 ppm (30 mg/m3) short-term exposure limit. NIOSH also assigns a "Skin" notation, which indicates that the cutaneous route of exposure, including mucous membranes and eyes, contributes to overall exposure [NIOSH 1992].
The American Conference of Governmental Industrial Hygienists (ACGIH) has assigned carbon disulfide a threshold limit value (TLV) of 10 ppm mg/m3) as a TWA for a normal 8-hour workday and a 40-hour workweek. The ACGIH also assigns a "Skin" notation to carbon disulfide [ACGIH 1994, p. 15].
The EPA requires that spills or accidental releases into the environment of 100 pounds or more of carbon disulfide be reported to the EPA.
Australia
Worksafe Australia:
Maximum time weighted average (TWA): 10 ppm 31 mg/m<3
As scientists who evolve with technology we treat innovation as a way of life, a life we dedicate to improvement and advancement of Safety, Health and Environment.
