United States
                            Environmental Protection
                     Office of Water
                                                                           EPA 811-F-95-003aa-T
                                                                                 October 1995
                            National Primary Drinking
                            Water Regulations
                            Polychlorinated Biphenyls (PQBs)

 CAS NUMBER: 1336-36-3

 COLOR/ FORM/ODOR:  PCB is generic term
   for group of organic chemicals which
   can be odorless or mildly aromatic
   solids or oily liquids; available in
   mixtures containing several PCBs and
   other organics as well.

 M.P.: 340 to 375 C     B.P.:  N/A

VAPOR PRESSURE: N/A; moderately volatile
  from water and soil

DENSITY/SPEC. GRAV.:- 1.44 at 30 C

SOLUBILITY: N/A; insoluble in water

  Koc generally above 5000; low
  mobility in soil, but may leach with
  mobile organic solvents.

                                                               BlOCONCENTRATION FACTOR:
                                                                 Log BCF - 3.26 to 5.27 in aquatic
                                                                 organisms; expected to bioconcentrate
                                                                 in aquatic organisms.

                                                               HENRY'S LAW'COEFFICIENT:
                                                                 3.3x10-4 to 5x10-5 atm-cu m/mole at 20

                                                               TRADE NAMES/SYNONYMS:
                                                                 PCB, Chlorinated diphenyl, Clophen,
                                                                 Kanechlor, Aroclor, Fenclor, Chlorextol,
                                                                 Dykanol, Inerteen, Monter, Pyralene,
                                                                 Santotherm, sovol, Therminol, Noflamol
  MCLG:     .zero mg/L
  MCL:       0.0005 mg/L
  HAL(child):  none

  Acute: EPA has found PCBs to potentially cause the
following  health  effects from short-term  exposures at
levels above the MCL: acne-like eruptions and pigmen-
tation of the skin; hearing and vision problems; spasms.
  Chronic:   PCBs have the potential  to cause the
following health effects from long-term exposure at levels
above the MCL: effects similar to acute poisonings;
irritation of nose; throat and gastrointestinal tracts;
changes in liver function.
  Cancer: There is some evidence that PCBs may have
the potential to cause cancer from a lifetime exposure at
levels above the MCL.

  Production of PCBs has decreased drastically: from
over 86 million Ibs. in 1970 to 35 million Ibs in 1977. EPA
banned most  uses of PCBs in 1979.  In 1975 it was
estimated that industries consumed PCBs  as follows:
capacitors, 70%; Transformers, 30%
  PCBs were formerly used in the USA as hydraulic
fluids, plasticizers, adhesives, fire retardants, way ex-
tenders, dedusting agents,  pesticide extenders, inks,
                                               lubricants, cutting oils, in heat transfer systems, carbon-
                                               less reproducing paper.

                                               RELEASE PATTERNS
                                                 Current evidence suggests that the major source of
                                               PCB release to  the environment is an environmental
                                               cycling process of PCBs previously introduced into the
                                               environment; this cycling process involves volatilization
                                               from ground surfaces (water, soil) into the atmosphere
                                               with subsequent removal from the atmosphere via wet/
                                               dry deposition and then revolatilization.  PCBs are also
                                               currently released to the environment from landfills con-
                                               taining PCB waste  materials and products, incineration
                                               of municipal refuse and sewage sludge, and improper (or
                                                 Toxic RELEASE INVENTORY -
                                                 RELEASES TO WATER AND LAND:
                                            1987 TO 1993
                                                 TOTALS (in pounds)       784

                                                 Top Five States
                                                 CA                     0
                                                 NJ                     0
                                                 KY                   250
                                                 WA                     0
                                                 TN                   255

                                                 Major Industries
                                                 Non-ferrous wire            0
                                                 Steel pipe/tubing            0
                                                 Pulp mills                0
October 1995
         Technical Version
                                                                           Printed on Recycled Paper

illegal) disposal of PCB materials, such as waste trans-
former fluid, to open areas.
  From 1987 to 1993, according to EPA's Toxic Chemi-
cal Release Inventory, PCB releases to land and water
totalled over 74,000 Ibs., of which about 99 percent was
to land. The bulk of these releases occurred in 1990 and
were primarily from non-ferrous wire drawing and insulat-
ing industries. The largest releases (10% or more of the
total) occurred in California.

  PCBs are  mixtures  of different congeners  of
chlorobiphenyl and the relative importance of the envi-
ronmental fate mechanisms generally depends on the
degree of chlorination. In general, the persistence of
PCBs increases with an increase in the degree of chlori-
nation. Mono-, di- and trichlorinated  biphenyls biode-
grade relatively rapidly, tetrachlorinated biphenyls biode-
grade slowly, and higher chlorinated biphenyls are resis-
tantto biodegradation. Although biodegradation of higher
chlorinated congeners may occur very slowly on an
environmental basis, no other degradation mechanisms
have been shown to be important in natural water and soil
systems; therefore,  biodegradation may be the ultimate
degradation process in water and soil.
  If released to soil, PCBs experience tight adsorption
with adsorption generally increasing with the degree of
chlorination of the PCB. PCBs will generally not leach
significantly in aqueous soil systems; the higher chlori-
nated congeners will have a lower tendency to leach than
the  lower chlorinated congeners.  In  the  presence of
organic solvents PCBs may leach quite rapidly through
soil. Vapor loss of PCBs from soil surfaces appears to be
an important fate mechanism with the rate of volatilization
decreasing with  increasing chlorination. Although the
volatilization rate may be low, the total loss by volatiliza-
tion over time may be significant because of the persis-
tence and stability of PCBs. Enrichment of the low-CI
PCBs occurs in the  vapor phase relative to the original
Aroclor; the residue will be enriched in the PCBs contain-
ing high Cl content.
  If released to water, adsorption to sediment and sus-
pended matter will be an important fate process;  PCB
concentrations in sediment and suspended matter have
been shown to be greater than in the associated water
column. Although adsorption can immobilize PCBs (es-
pecially the higher chlorinated congeners) for relatively
long periods of time, eventual resolution into the water
column has been shown to occur. The PCB composition
in the water will be enriched in the lower chlorinated PCBs
because of their greater water solubility, and the  least
water  soluble PCBs  (highest  Cl content) will remain
adsorbed. In the absence of adsorption, PCBs volatilize
relatively rapidly from water. However, strong PCB ad-
       sorption to sediment significantly competes with volatil-
       ization, with the higher chlorinated PCBs having longer
       half-lives than the lower chlorinated PCBs. Although the
       resulting volatilization rate may be low, the total loss by
       volatilization overtime may be significant because of the
       persistence and stability of the PCBs.
         If released to the atmosphere, PCBs will primarily exi4
       in the vapor-phase; the tendency to become associated
       with the particulate-phase will increase as the degree of
       chlorination of the PCB increases. The dominant atmo-
       spheric transformation process  is probably the vapor-
       phase reaction with hydroxyl radicals which has esti-
       mated  half-lives  ranging from  12.9 days  for
       monochlorobiphenyl   to    1.31    years    for
       heptachlorobiphenyl. Physical removal of PCBs from the
       atmosphere, which is very important environmentally, is
       accomplished by wet and dry deposition.
         PCBs have been shown to bioconcentrate significantly
       in aquatic organisms. Average log BCFs of 3.26 to 5.27,
       reported for various congeners  in aquatic organisms,
       show increasing accumulation with the more highly chlo-
       rinated congeners. The major PCB exposure routes to
       humans  are through food and drinking water, and  by
       inhalation of contaminated air. .
          INITIAL FREQUENCY-  4 quarterly samples every 3 years
          REPEAT FREQUENCY- If no detections during initial round:
                        2 quarterly per year if serving >3300 persons;
                        1 sample per 3 years for smaller systems
        TRIGGERS - Return to Initial Freq. if detect at congener-specific limits

        EPA 600/4-88-039            505; 508; 508A

        Granular Activated Charcoal,

        * EPA can provide further regulatory and other general information:
         EPA Safe Drinking Water Hotline - 800/426-4791

        * Other sources of lexicological and environmental fate data include:
        - Toxic Substance Control Act Information Line - 202/554-1404
         Toxics Release Inventory, National Library of Medicine - 301/496-6531
         Agency for Toxic Substances and Disease Registry - 404/639-6000
 October 1995
Technical Version
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