This standard operating procedure (SOP) outlines the handling and use of B-mercaptoethanol (BME). Review this document and supply the information required in order to make it specific to your laboratory. In accordance with this document, laboratories should use appropriate controls, personal protective equipment, and disposal techniques when handling BME.

BME is used as an enzyme reactivator in inhibited systems, a reducing agent in the fluorescent reaction of o-phthaldialdehyde, and amino-acids in alkaline media and is also used to dissociate proteins.

• BME has a very low odor threshold (0.12-0.64 ppm) and smells similar to the odorant used in natural gas. If the odor becomes widespread, people in nearby areas may suspect a natural gas leak. This can lead to calls to the fire department and/or evacuation of the building, which can be inconvenient and disruptive.

• BME can be toxic if ingested and fatal if inhaled or absorbed through the skin.

• Vapors can irritate the eyes, mucous membranes, and respiratory tract. Symptoms of inhalation exposure may include coughing, sore throat, and/or shortness of breath.

• When BME is heated to decomposition, toxic fumes including sulfur oxides and carbon oxides will be emitted.

• BME is combustible as a liquid or vapor.

• Reactions of BME with strong acids or alkali metals will release flammable hydrogen gas.

ALWAYS work with BME inside a chemical fume hood or 100% exhausted biological safety cabinet (Class II, Type B2).

• BME is incompatible with metals, oxidizing agents, acids, alkalis, calcium hypochlorite, aliphatic amines, and isocyanates.

• Purchase and use in the smallest practical quantities for the experiment being performed.

• Know the location of the nearest fire extinguisher before beginning work.

• Eliminate ignition sources such as open flames and hot surfaces.

• Keep containers closed as much as possible when not in use.

• Be aware of skin absorption as a possible route of exposure. Plan work so that minimal glove contact is expected, and purchase appropriate gloves for cleaning up small spills.

• If glove contact occurs, change gloves immediately.

At a minimum, double-glove using nitrile laboratory gloves and wear a lab coat and safety glasses when working with BME. If there is a possibility of splashing, wear chemical splash goggles and/or a face shield.

• Do not store near sources of ignition, oxidizing agents, acids, alkaline compounds, or any other incompatible materials.

• Store BME in a sealed secondary container in a well-ventilated area.

• The container must be tightly closed, resealed, and stored upright to avoid leakage.

• Avoid storing on the floor.

• Transport toxic liquids in secondary containment, preferably a polyethylene or other non-reactive acid/solvent bottle carrier.

• Suitable fire control devices (such as fire extinguishers) must be available at locations where flammable or combustible liquids are stored.

Handle and store hazardous waste following the guidelines above for work practice controls, transportation and storage. Contact OSEH Hazardous Materials Management at (734) 763-4568 for waste containers, labels, manifests, waste collection and for any questions regarding proper waste disposal. Also refer to OSEH’s Hazardous Waste webpage for more information.

 If the employee is in need of emergency medical attention, call 911 immediately.   

For an actual chemical exposure/injury:

• In case of skin contact: Flush the skin with copious amounts of water for at least 15 minutes, and then seek medical attention (see below).

• In case of eye contact: Flush contaminated eye(s) immediately with copious amounts of water for at least 15 minutes, and then seek medical attention (see below).

• In case of inhalation: Assist conscious persons to an area with fresh, uncontaminated air, and then seek medical attention (see below).

Contact OSEH for advice on symptoms of chemical exposure, or assistance in performing an exposure assessment.

Report all work related accidents, injuries, illnesses or exposures to Work Connections within 24 hours by completing and submitting the Illness and Injury Report Form. Follow the directions on the Work Connections website Forms Instructions to obtain proper medical treatment and follow-up.

Complete the OSEH Laboratory Incident and Near-Miss Report form.

TREATMENT FACILITIES:

U-M Occupational Health Services -- Campus Employees Mon-Fri 7:30 am - 4:30 pm

After hours - go to UM Hospital Emergency Dept. – Urgent Care Clinic C380 Med Inn building 1500 East Medical Center Drive, Ann Arbor (734) 764-8021

University Health Services -- University students (non-life threatening conditions) Mon-Fri 8 am – 4:30 pm, Sat 9 am – 12 pm

Contact for current hours as they may vary 207 Fletcher Street, Ann Arbor (734) 764-8320

UMHS Emergency Department -- after clinic hours or on weekends 1500 East Medical Center Drive, Ann Arbor, (734) 936-6666

Spill Procedure

• When a spill occurs, personal safety should always come first.

• Alert and clear everyone in the immediate area where the spill occurred.

Employees in the area should be prepared to clean up minor spills confined to the chemical fume hood. Wearing appropriate gloves (e.g., butyl rubber, Silver Shield®, nitrile), splash goggles, lab coat (and impermeable apron, if available), use an inert absorbent material (sorbent pads, vermiculite, dry sand) to clean up the spill. Do not use combustible materials (i.e. saw dust) to absorb spill. Contaminated PPE and clean-up materials must be placed in a sealed container for pick-up by OSEH-HMM (see waste disposal section for more information).

For large spills, or any spills of BME outside of the fume hood, contact the University of Michigan Division of Public Safety and Security (DPSS) by calling 911. Additional Spill Links:

• http://oseh.umich.edu/hazardous-waste/spill-response/

Report all emergencies, suspicious activity, injuries, spills, and fires to the University of Michigan Division of Public Safety and Security (DPSS) by calling 911 or texting 377911. Register with the University of Michigan Emergency Alert System via Wolverine Access.

All personnel are required to complete the General Laboratory Safety Training session (BLS025w or equivalent) via OSEH’s My LINC website. Furthermore, all personnel shall read and fully adhere to this SOP when handling BME.

I have read and understand the above SOP. I agree to contact my Supervisor or Lab manager if I plan to modify this procedure.

• Iharvey (talk) 19:42, 10 November 2016 (UTC)
• Elhabbal (talk) 21:43, 12 June 2017 (UTC)
• Reddj (talk)
• Mollyec (talk) 21:43, 12 September 2019 (UTC)

Prior Approval required – Is this procedure hazardous enough to warrant prior approval from the Laboratory Director? ☐ YES ☐ NO Laboratory Director Revision Date � Major Revisions (Tracking purposes only – Do not print as part of SOP)