CLOPHEN A 30 : A 60 1 : 1

Molecular Structure:

 Polychlorinated biphenyls (CAS NO.1336-36-3) are a class of organic compounds with 1 to 10 chlorine atoms attached to biphenyl, which is a molecule composed of two benzene rings. The chemical formula for PCBs is C₁₂H_10-xCl_x, where x = 1-10.
log P (octanol-water): 7.1
Water Solubility: 0.7 mg/L at 25 °C
Henry's Law Constant: 4.15E-04 atm-m³/mole 25 °C  
Atmospheric OH Rate Constant: 8.13E-13 cm³/molecule-sec 25 °C
Other names: PCBs, Arochlor, Phenochlor, and Clophen 
Synonyms of Polychlorinated biphenyls (CAS NO.1336-36-3): 1,1'-Biphenyl, chloro derivs ; Aroclors ; PCBs ; Polychlorinated biphenyls (containing 60% or more chlorine by MW) ; Polychlorinated biphenyls, liquid ; Polychlorinated biphenyls, liquid [UN2315] [Class 9] ; Polychlorinated biphenyls, solid ; Polychlorinated biphenyls, solid [UN2315] [Class 9] ; Polychlorobiphenyls ; UN2315
CAS NO: 1336-36-3
Classification Code: Environmental Pollutants ; Reproductive Effect ; TSCA Flag R [Subject to a Section 6 risk management rule under TSCA] ; TSCA UVCB ; Tumor data   

PCBs, originally termed "chlorinated diphenyls" were commercially produced as complex mixtures containing multiple isomers at different degrees of chlorination. In the United States, commercial production of PCBs was taken over in 1929 by Monsanto Company from Swann Chemical Company.
The toxicity associated with PCBs and other chlorinated hydrocarbons, including polychlorinated naphthalenes was recognized very early due to a variety of industrial incidents. A conference about the hazards was organized at Harvard School of Public Health in 1937, and a number of publications referring to the toxicity of various chlorinated hydrocarbons were published before 1940. Robert Brown reminded chemists in 1947.
PCB manufacture and use continued with few restraints until the 1970s.
Despite active research spanning five decades, extensive regulatory actions, and an effective ban on their production since the 1970s, PCBs still persist in the environment and remain a focus of attention.
The only North American producer, Monsanto Company, marketed PCBs under the trade name Aroclor from 1930 to 1977.
In the UK, closed uses of PCBs in new equipment were banned in 1981, when nearly all UK PCB synthesis ceased, but closed uses in existing equipment containing in excess of 5 litres of PCBs were not stopped until December 2000.

 Polychlorinated biphenyls (CAS NO.1336-36-3) were widely used for many applications, especially as dielectric fluids in transformers and capacitors and coolants.
They were used to make more flexible and flame-retardant plastics and are still used as insulating fluids in electrical transformers since there is no substitute in the application.

 Polychlorinated biphenyls (CAS NO.1336-36-3) are manufactured by chlorination of biphenyl. The conditions determine the degree of chlorination.

NTP 10th Report on Carcinogens. IARC Cancer Review: Group 2A IMEMDT    IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Man . 7 ,1987,p. 322.(World Health Organization, Internation Agency for Research on Cancer,Lyon, France.: ) (Single copies can be ordered from WHO Publications Centre U.S.A., 49 Sheridan Avenue, Albany, NY 12210) ; Human Limited Evidence IMEMDT    IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Man . 18 ,1978,p. 43.(World Health Organization, Internation Agency for Research on Cancer,Lyon, France.: ) (Single copies can be ordered from WHO Publications Centre U.S.A., 49 Sheridan Avenue, Albany, NY 12210) . Reported in EPA TSCA Inventory.

Confirmed carcinogen with carcinogenic and tumorigenic data. Moderately toxic by ingestion. Some are poisons by other routes. Experimental reproductive effects.
Like the chlorinated naphthalenes, the chlorinated diphenyls have two distinct actions on the body, namely, a skin effect and a toxic action on the liver. This hepato-toxic action of the chlorinated diphenyls appears to be increased if there is exposure to carbon tetrachloride at the same time. The higher the chlorine content of the diphenyl compound, the more toxic it is liable to be. Oxides of chlorinated diphenyls are more toxic than the unoxidized materials. In persons who have suffered systemic intoxication, the usual signs and symptoms are nausea, vomiting, loss of weight, jaundice, edema, and abdominal pain. If the liver damage has been severe the patient may pass into a coma and die.
Combustible when exposed to heat or flame. When heated to decomposition they emit highly toxic fumes of Cl⁻. See also specific compounds.

DFG MAK: Suspected Carcinogen
NIOSH REL: TWA ( Polychlorinated biphenyls ) 0.001 mg/m³
DOT Classification:  9; Label: CLASS 9

For occupational chemical analysis use NIOSH: Polychlorobiphenyls, 5503.

Due to PCB's toxicity and classification as persistent organic pollutants, PCB production was banned by the United States Congress in 1976 and by the Stockholm Convention on Persistent Organic Pollutants in 2001.