Standard Operating Procedures
Laboratory Specific
Chemical: 3,3’-Dichlorobenzidine (and its salts)
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Laboratory Safety Manual and Chemical Hygiene Plan.
Refer to instructions for assistance.
_____________________________________________________________________________
Department:________________________
Date when SOP was written:_______
Date when SOP was approved by the lab supervisor: ___________________
Principal Investigator:___________________________________________________
Internal Laboratory Safety Coordinator/Lab Manager:___________________________________
Laboratory Phone:____________________ Office Phone:_____________________
Emergency Contact:____________________________________________________
(Name and Phone Number)
Location(s) covered by this SOP:__________________________________________
(Building/Room Number)
_____________________________________________________________________________
Type of SOP:
Process
Hazardous Chemical
Hazardous Class
Purpose
3,3'-Dichlorobenzidine is a gray-to-purple colored crystalline solid. It changes from a solid to a
gas very slowly. 3,3'-Dichlorobenzidine salt, the major form in actual use, is a stable, off-white
colored crystalline solid that does not evaporate. Neither 3,3'-dichlorobenzidine nor its salt occur
naturally in the environment. They are manufactured for use in the production of pigments for
printing inks, textiles, plastics and enamels, paint, leather, and rubber. Whether 3,3'dichlorobenzidine or the salt is present as such depends on the acidity of the soil or water as well
as other factors. In most environmental samples, such as water and soils, 3,3'-dichlorobenzidine
would be expected to exist in the free amino form, not as the salt.
Physical & Chemical Properties/Definition of Chemical Group
CAS#:
91-94-1
Class:
Carcinogen
Molecular formula:
NH2ClC6H3C6H3ClNH2
Boiling Point:
788°F
Melting Point:
271°
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Potential Hazards/Toxicity
3,3'-Dichlorobenzidine is a carcinogen (known to cause cancer to humans).
 It may be harmful if inhaled, and may cause respiratory tract irritation. It is toxic if
swallowed, and may be harmful if absorbed through skin, causing skin irritation. Also,
3,3'-Dichlorobenzidine may cause eye irritation.
 Exposure routes include: inhalation, skin absorption, ingestion, skin and/or eye contact
 Signs and symptoms of exposure include: Skin sensitization; dermatitis; headache;
cough, sore throat; dizziness; caustic burns; frequent urination, dysuria, hematuria (blood
in the urine); GI upset; upper respiratory infection; [potential occupational carcinogen].
 Repeated absorption may result in bladder tumors. This is or contains a component that
has been reported to be carcinogenic based on its IARC, OSHA, ACGIH, NTP, or EPA
classification.
 Affected organs include: bladder, liver, lungs, skin & GI tract.
Personal Protective Equipment (PPE)

All persons shall wear personal protective equipment when handling 3,3'Dichlorobenzidine. This includes wearing a lab coat, safety glasses, protective gloves,
long pants and closed toe shoes. Gloves should be inspected prior to use, removed
properly (without touching glove’s outer surface), and disposed of appropriately. Wash
and dry hands after using 3,3'-Dichlorobenzidine.

Protective gloves should be worn at all times when handling this chemical. Nitrile gloves
should be used for incidental contact, and double nitrile gloves when handling the pure
material or concentrated stock solutions

The lab coat should be decontaminated and gloves should be disposed of, as 3,3'Dichlorobenzidine may be absorbed and retained on clothing and/or shoes.

Leave lab coats, gloves, and other personal protective equipment in the lab once your
work is complete to prevent the spread of this or other chemicals outside of the lab.

Where risk assessment shows air-purifying respirators are appropriate use a full-face
particle respirator type N100 (US) or type P3 (EN 143) respirator cartridges as a backup
to engineering controls. If the respirator is the sole means of protection, use a full-face
supplied air respirator. Use respirators and components tested and approved under
appropriate government standards such as NIOSH (US) or CEN (EU).
Engineering Controls
Always handle 3,3'-Dichlorobenzidine in a certified chemical fume hood.
First Aid Procedures



Inhalation or Ingestion: In the case of ingestion, obtain medical attention immediately. If
breathed in, move person into fresh air. If not breathing, give artificial respiration. Consult
a physician.
Eyes exposure: Immediately flush eyes with copious amounts of water for at least 15
minutes, preferably in an emergency eyewash station.
Skin exposures: In the event of skin exposure, remove contaminated clothing and
immediately wash the affected area with soap and copious amounts of water for 15
minutes.
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Special Handling and Storage Requirements
1. All work with 3,3'-Dichlorobenzidine is to be done in a designated area in order to keep
contamination to a minimum. Any persons in this area are required to wear personal
protective equipment. Safety shower and eye wash stations should be easily accessible
where 3,3'-Dichlorobenzidine is used.
2. All laboratory equipment used in the designated area are to be labeled as "3,3'Dichlorobenzidine contaminated" and are not to be removed from the area without first
being decontaminated.
3. Avoid contact with skin and eyes. Avoid formation of dust and aerosols.
4. Provide appropriate exhaust ventilation at places where dust is formed. Normal measures
for preventive fire protection.
5. Keep container tightly closed in a dry and well-ventilated place
6. Light sensitive. Keep in a dry place.
Spill and Accident Procedure
Chemical Spill Dial 911 and x59797
Spill – Help contaminated or injured persons. Evacuate the spill area. Avoid breathing vapors.
Eliminate sources of ignition if the chemical is flammable. If possible, confine the spill to a small
area using a spill kit or absorbent material. Keep others from entering contaminated area (e.g.,
use caution tape, barriers, etc.).
Small (<1 L) – If you have training, you may assist in the clean-up effort. Use appropriate
personal protective equipment and clean-up material for chemical spilled. Double bag spill waste
in clear plastic bags, label and take to the next chemical waste pick-up.
Large (>1 L) – Dial 911 (or 310-825-1491 from cell phone) and EH&S at x59797 for
assistance.
Chemical Spill on Body or Clothes – Remove clothing and rinse body thoroughly in
emergency shower for at least 15 minutes. Seek medical attention. Notify supervisor and EH&S
at x59797 immediately.
Chemical Splash Into Eyes – Immediately rinse eyeball and inner surface of eyelid with
water for 15 minutes by forcibly holding the eye open. Seek medical attention. Notify supervisor
and EH&S at x59797 immediately.
Medical Emergency Dial 911 or x52111
Life Threatening Emergency, After Hours, Weekends And Holidays – Dial 911
(or 310-825-1491 from cell phone) or contact the Ronald Reagan UCLA Medical Center
(emergency room) directly at x52111 (located at 757 Westwood Plaza, enter from Gayley
Avenue). Note: All serious injuries must be reported to EH&S at x59797 within 8 hours.
Non-Life Threatening Emergency– Go to the Occupational Health Facility (OHF),
x56771, CHS room 67-120 (This is on the 6th floor, 7th corridor, room 120. Enter through the
School of Dentistry on Tiverton Drive and proceed to the “O” elevator to the 6th floor.)Hours: M F, 7:30 a.m. to 4:30 p.m. At all other times report to Ronald Regan UCLA Medical Center
(emergency room) at x52111. Note: All serious injuries must be reported to EH&S at x59797
within 8 hours.
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Needle stick/puncture exposure (as applicable to chemical handling procedure)– Wash
the affected area with antiseptic soap and warm water for 15 minutes. For mucous membrane
exposure, flush the affected area for 15 minutes using an eyewash station. Page the needle stick
nurse by dialing 231 from a campus phone, enter 93333 when prompted and then enter your
extension. Hours: M – F, 8:00 a.m. to 4:00 p.m. At all other times report to Ronald Regan UCLA
Medical Center (emergency room) at x52111. Note: All needle stick/puncture exposures must be
reported to EH&S at x59797 within 8 hours.
Decontamination/Waste Disposal Procedure
Waste disposal procedures
1. All 3,3'-Dichlorobenzidine waste shall be disposed of into waste containers specifically
designated for 3,3'-Dichlorobenzidine waste.
2. Wash contaminated surfaces to remove any residue.
3. Once the waste container is full, dispose of according the UCLA EH&S hazardous waste
guidelines.
4. Dispose of contaminated packing material as unused product.
Material Safety Data Sheet (MSDS) Location
(State the location of MSDS)
Hardcopy or electronic copy must be available.
Online MSDS can be accessed at http://msds.ehs.ucla.edu.
Protocol/Procedure
(Add specific description of procedure.)
Note: Any deviation from this SOP requires written approval from PI.
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Documentation of Training (signature of all users is required)
I have read and understand the content of this SOP:
Name
Signature
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Date