Bromoform

by Posted on

2022-05-20

Bromoform (CHBr3) is a pale yellowish liquid with a sweet odour similar to chloroform. It is soluble in about 800 parts water and is miscible with alcohol, benzene, chloroform, ether, petroleum ether, acetone, and oils. It is also non-flammable and readily evaporates into the air. Bromoform is produced naturally by phytoplankton and seaweeds in the ocean and this is thought to be the predominant source to the environment. However, locally significant amounts of bromoform enter the environment formed as disinfection by-products known as the trihalomethanes when chlorine is added to drinking water to kill bacteria. [1,2]

Uses [3]

Bromoform is used as an intermediate in geological assaying and as a solvent for waxes, greases, and oils. It is also used in shipbuilding, aircraft, and aerospace industries and as an ingredient in fire-resistant chemicals and gauge fluid. Traces of bromoform are likely to be present in swimming pools, municipal waters, and wastes as a result of chlorination in the presence of naturally occurring bromide ions and humic substances. It is hypothesised that bromoform may be formed by the haloform reaction which occurs during the chlorination of water.

Sources & Routes of Exposure [2, 4]

Studies have indicated that bromoform can easily enter the body after swallowing them in water or breathing them in air. In addition, they can enter the body through the skin (for example, by washing or showering in water containing these chemicals). Some portion of bromoform entering the body may be broken down to other compounds. Bromoform and its breakdown products can be removed from the body by being exhaled from the lungs. These chemicals leave the body fairly rapidly. Bromoform does not tend to build up in the body; 50-90% of the amount that enters the body is removed within 8 hours. The principal route of human exposure to bromoform is from drinking water that has been disinfected with chlorine, bromine, or bromine compounds. Bromoform has been detected in swimming pools that have been disinfected with bromine or bromine compounds; therefore, exposure to low levels could occur from inhalation of bromoform that has evaporated into the air or through the skin from bromoform in the water. In addition, exposure could also occur from inhalation of ambient air near factories or laboratories that use bromoform. Another place for exposure is near a chemical waste site where bromoform leaked into water or soil.

Health Effects [2]

Acute Effects

Human exposure to large amounts of bromoform through inhalation and oral exposure can result in unconsciousness. Animal studies, combined with limited observations in humans, indicate that the principal adverse health effects associated with short-term inhalation or oral exposure to high levels of bromoform are CNS depression, resulting in the slowing down of normal brain activities, sedation, narcosis, and sleep, and liver and kidney injury.

Chronic Effects

The long-term effects of exposure to bromoform in humans have not been studied. Animal studies indicate effects on the liver, kidney, and CNS from chronic oral exposure to bromoform. The Reference Dose (RfD) for bromoform is 0.02 milligrams per kilogram body weight per day (mg/kg/d) based on hepatic lesions in rats. The United States Environmental Protection Agency has determined that there are insufficient data to calculate a Reference Concentration (RfC) for bromoform.

Cancer Risk

The only available human cancer study suggested a positive correlation between levels of bromoform in drinking water and the incidence of several tumour types. However, this study was considered to be incomplete and preliminary because the study design did not permit consideration of variables such as personal habits, residential histories, and past exposures. Animal studies have demonstrated an increase in the incidences of liver and intestinal tumours following oral exposure to bromoform. EPA considers bromoform to be a probable human carcinogen and has ranked it in EPA’s Group B2.

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. WARM water MUST be used. Get medical attention.
  • Skin Contact: In case of contact, immediately flush skin with plenty of water. Cover the irritated skin with an emollient. Remove contaminated clothing and shoes. Wash clothing before reuse. Thoroughly clean shoes before reuse. Get medical attention.
  • Serious Skin Contact: Wash with a disinfectant soap and cover the contaminated skin with an anti-bacterial cream. Seek immediate medical attention.
  • Inhalation: If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get 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 unless directed to do so by medical personnel. Never give anything by mouth to an unconscious person. If large quantities of this material are swallowed, call a physician immediately. Loosen tight clothing such as a collar, tie, belt or waistband.

Exposure Control & Personal Protection

Engineering Controls

Provide exhaust ventilation or other engineering controls to keep the airborne concentrations of vapours below their respective threshold limit value.

  • Personal Protection Equipment

  • 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 (A self contained breathing apparatus should be used to avoid inhalation of the product);
  • Boots;
  • Gloves;

Please note: Suggested protective clothing might not be sufficient; consult a specialist BEFORE handling this product.

Regulation

United States

OSHA: The Occupational Safety & Health Administration has set the following Permissible Exposure Limit (PEL) for bromoform:

  • General Industry: 29 CFR 1910.1000 Table Z-1 – 0.5 ppm, 5 mg/m3 TWA; Skin
  • Construction Industry: 29 CFR 1926.55 Appendix A – 0.5 ppm, 5 mg/m3 TWA; Skin
  • Maritime: 29 CFR 1915.1000 Table Z-Shipyards – 0.5 ppm, 5 mg/m3 TWA; Skin

ACGIH: American Conference of Governmental Industrial Hygienists has set a Threshold Limit Value (TLV) for bromoform of 0.5 ppm, 5.2 mg/m3 TWA; Skin; Appendix A3 – Confirmed Animal Carcinogen with Unknown Relevance to Humans

NIOSH: The National Institute for Occupational Safety and Health has set a Recommended Exposure Limit (REL) for bromoform of 0.5 ppm, 5.2 mg/m3 TWA; Skin

Australia [7]

Safe Work Australia: Safe Work Australia has set a time weighted average concentration (TWA) for bromoform of 0.5ppm or 5.2mg/m3 for a 40 hour work week.

References

http://en.wikipedia.org/wiki/Bromoform

http://www.epa.gov/ttn/atw/hlthef/bromofor.html

http://scorecard.goodguide.com/chemical-profiles/html/bromoform.html

http://www.atsdr.cdc.gov/phs/phs.asp?id=711&tid=128

http://www.sciencelab.com/msds.php?msdsId=9927109

https://www.osha.gov/dts/chemicalsampling/data/CH_222000.html

http://www.safeworkaustralia.gov.au/sites/SWA/about/Publications/Documents/772/Workplace-exposure-standards-airborne-contaminants.pdf