Carbon Disulfide

2022-04-01

Carbon disulfide is a colourless volatile liquid with the formula CS2. The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical non-polar solvent. [1] Pure carbon disulfide is a colourless liquid with a pleasant odour that is like the smell of chloroform. The impure carbon disulfide is contaminated with foul-smelling impurities, such as carbonyl sulfide. Carbon disulfide evaporates at room temperature, and the vapour is more than twice as heavy as air. It easily explodes in air and also catches fire very easily. In nature, small amounts of carbon disulfide are found in gases released to the earth’s surface as, for example, in volcanic eruptions or over marshes. Commercial carbon disulfide is made by combining carbon and sulphur at very high temperatures. [2]

Uses [3]

Carbon disulfide’s most important industrial use has been in the manufacture of regenerated cellulose rayon (by the viscose process) and cellophane. Another principal industrial use for carbon disulfide has been as a feedstock for carbon tetrachloride production. It has also been used to protect fresh fruit from insects and fungus during shipping, in adhesives for food packaging, and in the solvent extraction of growth inhibitors. Carbon disulfide has also been highly suitable for other industrial applications including the vulcanisation and manufacture of rubber and rubber accessories; the production of resins, xanthates, thiocyanates, plywood adhesives, and flotation agents; solvent and spinning-solution applications, primarily in the manufacture of rayon and polymerisation inhibition of vinyl chloride; conversion and processing of hydrocarbons; petroleum-well cleaning; brightening of precious metals in electroplating; rust removal from metals; and removal and recovery of metals and other elements from waste water and other media. In agriculture, carbon disulfide has been widely used as a fumigant to control insects in stored grain, and to remove botfly larva infestations from the stomachs of horses and ectoparasites from swine. Use of carbon disulfide as a grain fumigant in the USA was voluntarily cancelled after 1985.

Sources & Routes of Exposure

Sources of Exposure [3, 4]

The main route of exposure to this compound is in the workplace. Workers in plants that use carbon disulfide in their manufacturing processes have a high degree of exposure potential. Releases of carbon disulfide from industrial processes are almost exclusively to the air; individuals in proximity to these sites may be exposed. Exposure may result from breathing air, drinking water, or eating foods that contain it. People may also be exposed through skin contact with soil, water, or other substances that contain carbon disulfide. Furthermore, low amounts of carbon disulfide may be emitted naturally from volcanoes and marshes.

Routes of Exposure [3]

Probable routes of human exposure to carbon disulfide are inhalation, ingestion, and skin contact.

Health Effects [4]

Acute Effects

Acute inhalation exposure of humans caused changes in breathing and some chest pains during an accidental release of carbon disulfide. Nausea, vomiting, dizziness, fatigue, headache, mood changes, lethargy, blurred vision, delirium, and convulsions have also been reported in humans acutely exposed by inhalation. Brain chemistry changes and sensory and motor nerve conduction alterations were observed in rats acutely exposed to carbon disulfide by inhalation. Tests involving acute exposure of rats, mice, and rabbits have shown carbon disulfide to have low acute toxicity from inhalation and moderate acute toxicity by ingestion.

Chronic Effects

Neurotoxic effects have been observed in chronic human and animal inhalation studies. Behavioural and neurophysiological changes, reduced nerve conduction velocity, peripheral neuropathy, and polyneuropathy have been observed in chronically exposed workers. An increased incidence of coronary heart disease has been observed in an epidemiological study of workers who chronically inhaled carbon disulfide in the workplace. Concomitant exposure to other chemicals and a failure to control for other coronary heart disease risk factors have been noted with this study. An increased incidence of angina has been reported in another occupational study. Muscle pain, headaches, and general fatigue have been reported by workers chronically exposed to carbon disulfide in the air. Ocular effects have been observed in chronically exposed workers. Workers who handled fibres made from a polymer solution in carbon disulfide developed blisters and eczematous lesions on their hands. Chronic inhalation exposure has been observed to affect the CNS, blood, liver, and kidneys in animals. The Reference Concentration (RfC) for carbon disulfide is 0.7 milligrams per cubic metre (mg/m3) based on neurological effects in humans. The Reference Dose (RfD) for carbon disulfide is 0.1 milligrams per kilogram body weight per day (mg/kg/d) based on foetal toxicity/malformations in rabbits.

Reproductive/Developmental Effects

Reproductive effects, such as decreased sperm count and decreased libido in men and menstrual disturbances in women, have been reported from occupational settings involving inhalation exposure to carbon disulfide. Developmental effects, including skeletal and visceral malformations, embryotoxicity, and functional and behavioural disturbances, have been observed in several animal studies across a wide exposure range. Pharmacokinetic studies indicate that carbon disulfide and its metabolites cross the placenta and localise in the target organs of the foetus (brain, blood, liver, and eyes).

Cancer Risk

In a study of workers exposed by inhalation to carbon disulfide and other solvents, an increased incidence of lymphatic leukaemia was reported. However, there were many confounding factors in this study, making it difficult to interpret the results. EPA has not classified carbon disulfide for human carcinogenicity.

Safety [5]

First Aid Measures

  • Eye Contact: Check for and remove any contact lenses. Immediately flush eyes with running water for at least 15 minutes, keeping eyelids open. Cold water may be used. Do not use an eye ointment. Seek medical attention.
  • Skin Contact: After contact with skin, wash immediately with plenty of water. Gently and thoroughly wash the contaminated skin with running water and non-abrasive soap. Be particularly careful to clean folds, crevices, creases and groin. Cover the irritated skin with an emollient. If irritation persists, seek medical attention. Wash contaminated clothing before reusing.
  • Serious Skin Contact: Wash with a disinfectant soap and cover the contaminated skin with an anti-bacterial cream. Seek medical attention.
  • Inhalation: Allow the victim to rest in a well-ventilated area. Seek immediate medical attention.
  • Serious Inhalation: Evacuate the victim to a safe area as soon as possible. Loosen tight clothing such as a collar, tie, belt or waistband. If breathing is difficult, administer oxygen. If the victim is not breathing, perform mouth-to-mouth resuscitation. Seek medical attention.
  • Ingestion: Do not induce vomiting. Loosen tight clothing such as a collar, tie, belt or waistband. If the victim is not breathing, perform mouth-to-mouth resuscitation. Seek immediate medical attention.

Fire Data

Carbon disulfide is flammable in presence of open flames and sparks, of oxidising materials. Liquid carbon disulfide is flammable, soluble or dispersed in water. Dry chemical powder should be used for small fires and alcohol foam, water spray or fog should be used on large fires.

Exposure Controls and Personal Protection

Engineering Controls

Exhaust ventilation or other engineering controls should be used to keep the airborne concentrations of vapours below their respective threshold limit value. Ensure that eyewash stations and safety showers are proximal to the workstation location.

Personal Protective Equipment

The following personal protective is recommended when handling carbon disulfide:

  • Splash goggles;
  • Lab coat;
  • Vapour respirator (be sure to use an approved/certified respirator or equivalent);
  • Gloves

Personal Protection in Case of a Large Spill:

  • Splash goggles;
  • Full suit;
  • Vapour respirator;
  • Boots;
  • Gloves
  •  A self-contained breathing apparatus should be used to avoid inhalation of the product.
  • Note: Suggested protective clothing might not be sufficient; consult a specialist BEFORE handling this product.

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
  • Harmful: concentration cut-off level: 0.20 % weight/weight
  • Toxic: concentration cut-off level: 1 % weight/weight
  • Irritant: concentration cut-off level: 20 % weight/weight

References

  1. http://en.wikipedia.org/wiki/Carbon_disulfide
  2. http://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=473&tid=84
  3. http://www.npi.gov.au/substances/carbon-disulfide/index.html
  4. http://www.epa.gov/ttn/atw/hlthef/carbondi.html
  5. https://www.sciencelab.com/msds.php?msdsId=9927125
  6. http://www.osha.gov/SLTC/healthguidelines/carbondisulfide/recognition.html