2,3',4,4',5,5'-Hexachlorobiphenyl

  • 1,1'-Biphenyl, 2,3',4,4',5,5'-hexachloro-
  • PCB 167
Formula
C12H4Cl6
Structure

Registry Numbers and Inventories.
CAS
52663-72-6
UN (DOT)
2315
Beilstein/Gmelin
4017743

Properties.
Formula
C12H4Cl6
Formula mass
360.86
Melting point, °C
125 - 127
Boiling point, °C
383
Critical temperature
610
Critical pressure
24.2
Solubility in water
1.1 g/L (25 C)
Partition coefficient, pKow
7.06

Hazards and Protection.
Storage
PBC material should be stored in closed containers, in ventilated areas srp: with appropriate air pollution control equipment.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Workers should be provided with suitable long-sleeved overalls, boots, overshoes, and bib-type aprons that cover the boot tops, and gloves. Safety glasses with side shields or goggles should be used for eye protection.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent dust cloud. Avoid inhalation of asbestos dust.
Stability
PCBs are chemically very inert and are stable to conditions of hydrolysis and oxidation in industrial use.
Incompatibilities
Liquid chlorine reacts exothermically with polychlorinated biphenyl heat transfer liquid.

Fire.
Fire fighting
Small Fires: Dry chemical, carbon dioxide, water spray or regular foam. Large Fires: Water spray, fog or regular foam.
Fire potential
Flame resistant.
Hazards
Containers may explode when heated.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.

Health.
Exposure limit(s)
IDHL: NIOSH considers chlorodiphenyl containing 54% chlorine to be potential occupational carcinogens.
Exposure effects
Weakness and numbness of the extremities and headache have been reported. Neurobehavioral and psychomotor impairment have been reported after occupational and in utero exposure. One of the potential symptoms of occupational PCB overexposure is decreased birth weight in offspring of exposed mothers. <br>Although relative small quantities of PCBs reach the fetus, significant PCB overexposure can cause teratogenic effects. PBBs are experimental teratogens. <br>Both PCBs and PBBs concentrate in milk.
   Ingestion
Gi upset and diarrhea have been reported.
   Inhalation
Inhalation of material may be harmful.
   Skin
Chloracne is a specific skin reaction associated with cyclic halogenated compounds. Children with in utero high exposures appear to have a higher rate of dermal reactions, including hyperpigmentation, acne and itching.
   Eyes
See Skin.

First aid
 
   Ingestion
Emesis - in almost all cases, ingestions of pcbs or pbbs will not be recognized until long after vomiting would be of any value. Vomiting of the pure substance may cause aspiration. Activated charcoal - the value of administering activated charcoal for an acute, known ingestion is unknown. Activated charcoal is a fairly benign treatment, and therefore, should be considered after acute ingestion. Activated charcoal: administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents. There is little specific treatment. Patients should be monitored for increased hepatic enzymes, chloracne, and the nonspecific eye, gastrointestinal, and neurologic symptoms seen in the yusho poisonings.
   Inhalation
Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with beta2 agonist and corticosteroid aerosols.
   Skin
A post-contamination washing cannot be assumed to remove pcbs. In animal studies only 59 percent of applied pcbs were removed from the skin with immediate washings with water and acetone, and only 1 percent was removed washing 24 hours after exposure. Multiple soap and water washings are necessary.
   Eyes
Immediately flush with running water for at least 20 minutes.

Transport.
UN number
2315
Response guide
Hazard class
9
Packing Group
II