United States
Environmental Protection
Agency
Office of Water
Regulations and Standards
Washington, DC 20460
Water
                            June, 1985
Environmental Profiles
and Hazard Indices
for Constituents
of Municipal Sludge:
Benzidine

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                                 PREFACE
     This document is one of  a  series  of preliminary assessments dealing
with  chemicals  of potential  concern  in municipal  sewage sludge.   The
purpose of these  documents  is to:  (a)  summarize  the available data for
the  constituents  of  potential  concern,  (b)  identify  the key environ-
mental pathways  for  each  constituent  related to  a reuse and disposal
option (based on  hazard  indices), and  (c)  evaluate  the  conditions under
which such a pollutant may  pose a hazard.   Each document provides a sci-
entific basis  for making an  initial  determination  of whether  a pollu-
tant, at levels currently observed in  sludges, poses  a  likely hazard to
human health  or   the  environment  when  sludge  is  disposed  of  by  any of
several methods.   These methods  include landspreading on  food chain or
nonfood chain  crops,  distribution  and marketing  programs,  landfilling,
incineration antl  ocean disposal.

     These documents  are intended to  serve as a rapid  screening tool to
narrow an initial list of pollutants to those  of  concern.   If a signifi-
cant hazard  is  indicated by  this preliminary analysis, a  more detailed
assessment will  be  undertaken  to  better  quantify  the  risk  from  this
chemical  and  to derive  criteria  if' warranted.   If a hazard  is shown to
be unlikely, no further  assessment will be conducted  at  this  time;  how-
ever, a  reassessment will  be  conducted after  initial  regulations  are
finalized.  In no  case,  however,  will   criteria be  derived  solely on the
basis of  information presented in this  document.

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                            TABLE OF CONTENTS


                                                                     Page

1.  INTRODUCTION	  1-1

2.  PRELIMINARY CONCLUSIONS FOR BENZIDINE IN MUNICIPAL SEWAGE
      SLUDGE	  2-1

    Landspreading and Distribution-and-Marketing 	  2-1

    Landfilling 	  2-1

    Incineration 	  2-1

    Ocean Disposal 	  2-1

3.  PRELIMINARY HAZARD INDICES FOR BENZIDINE IN MUNICIPAL SEWAGE
      SLUDGE	  3-1

    Landspreading and Distribution-and-Marketing 	  3-1

    Landf illing 	  3-1

    Incineration 	  3-1

    Ocean Disposal 	  3-1

         Index of seawater concentration resulting
           from initial mixing of sludge (Index 1) 	  3-1
         Index of seawater concentration representing
           a 24-hour dumping cycle (Index 2) 	  3-5
         Index of toxicity to aquatic life (Index 3)  	  3-6
         Index of human cancer risk resulting
           from seafood consumption (Index 4) 	  3-8

4.  PRELIMINARY DATA PROFILE FOR BENZIDINE IN MUNICIPAL SEWAGE
      SLUDGE	;	  4-1

    Occurrence	  4-1

         Sludge 	  4-1
         Soil - Unpolluted 	  4-1
         Water - Unpolluted 	  4-1
         Air	  4-2
         Food 	  4-2

    Human Effects 	  4-2

         Ingestion 	  4-2
         Inhalation	  4-2

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                            TABLE OF CONTENTS
                               (Continued)
                                                                     Page

    Plant Effects 	  4-3

    Domestic Animal and Wildlife Effects 	  4-3

         Toxicity 	  4-3
         Uptake	  4-4

    Aquatic Life Effects 	  4-4

         Toxicity (water concentration causing)  	  4-4
         Uptake	  4-4

    Soil Biota Effects	  4-4

    Physicochemical Data for Estimating Fate and Transport 	  4-5

5.  REFERENCES	  5-1

APPENDIX.  PRELIMINARY .HAZARD INDEX CALCULATIONS FOR
    BENZIDINE IN MUNICIPAL SEWAGE SLUDGE 	  A-l
                                   111

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                                SECTION 1

                               INTRODUCTION
     This  preliminary  data  profile  is  one  of  a  series  of  profiles
dealing  with chemical  pollutants  potentially of  concern  in  municipal
sewage  sludges.    Benzidine  was   initially  identified  as   being  of
potential  concern  when  sludge is  ocean  disposed."' This  profile  is  a
compilation  of  information  that  may  be  useful  in  determining  whether
benzidine poses an actual hazard  to  human  health or the environment when
sludge is disposed of by these methods.
     The  focus  of  this  document  is  the  calculation  of  "preliminary
hazard  indices"  for  selected  potential exposure  pathways,  as  shown  in
Section  3.   Each  index illustrates  the hazard  that could result from
movement  of  a -pollutant  by  a given  pathway  to  cause  a  given  effect
(e.g., sludge •* seawater •* marine organisms  •*  human  toxicity).     The
values and assumptions  employed  in these  calculations  tend  to  represent
a  reasonable "worst  case";  analysis- of error  or  uncertainty  has been
conducted  to a limited  degree.   The  resulting  value  in most  cases  is
indexed  to  unity;  i.e.,  values  >1  may  indicate  a potential  hazard,
depending upon the assumptions of  the calculation.
     The data used for  index calculation have been  selected  or  estimated
based  on  information  presented   in  the  "preliminary  data   profile",
Section 4.   Information  in  the profile  is based  on a compilation  of the
recent  literature.    An  attempt  has been  made  to  fill  out the  profile
outline to the  greatest  extent possible.  However,  since  this  is  a pre-
liminary analysis,  the literature  has not been exhaustively perused.
     The  "preliminary conclusions" drawn  from each  index in   Section  3
are  summarized  in Section  2.   The preliminary  hazard  indices will  be
used as a  screening "tool  to  determine which  pollutants  and  pathways may
pose a hazard.  Where a potential hazard  is  indicated  by interpretation
of  these  indices,  further analysis will  include a more  detailed  exami-
nation  of  potential  risks  as well  as   an  examination  of  site-specific
factors.   These more rigorous evaluations   may  change the  preliminary
conclusions  presented in  Section 2,  which  are  based  on a  reasonable
"worst case" analysis.
     The  preliminary   hazard   indices   for   selected   exposure   routes
pertinent to ocean disposal practices are  included  in this profile.  The
calculation  formulae  for  these indices  are  shown in the Appendix.   The
indices are rounded to two significant figures.
* Listings  were  determined  by  a  series  of  expert  workshops  convened
  during  March-May,  1984  by   the  Office   of   Water   Regulations  and
  Standards (OWRS)  to  discuss landspreading,  landfilling,  incineration,
  and ocean disposal, respectively,  of  municipal  sewage  sludge.
                                   1-1

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                                SECTION 2

    PRELIMINARY CONCLUSIONS  FOR  BENZIDINE IN MUNICIPAL SEWAGE SLUDGE
     The following  preliminary  conclusions  have  been  derived  from the
     calculation  of   "preliminary  hazard   indices",   which  represent
     conservative or "worst  case" analyses  of  hazard.   The  indices and
     their  basis and  interpretation are  explained in Section  3.   Their
     calculation formulae are shown in the Appendix.

  I. LANDSPREADING AND DISTRIBUTION-AND-MARKETING

     Based  on  the  recommendations  of  the experts  at the  OWRS meetings
     (April-May, 1984),  an  assessment of  this  reuse/disposal  option is
     not being-  conducted  at  this  time.    EPA  reserves   the  right  to
     conduct  such an assessment for this  option in the future.

 II. LANDFILLING

     Based  on  the  recommendations  of  the experts  at the  OWRS meetings
     (April-May, 1984),  an  assessment of  this  reuse/disposal  option is
     not being  conducted  at  this  time.    EPA  reserves   the  right  to
     conduct  such an assessment for this  option in the future.

III. INCINERATION

     Based  on  the  recommendations  of  the experts  at the  OWRS meetings
     (April-May, 1984),  an  assessment of  this  reuse/disposal  option is
     not being  conducted  at  this  time.    EPA  reserves   the  right  to
     conduct  such an assessment for this  option in the future.

 IV. OCEAN  DISPOSAL

     Increases   in  seawater  concentration of  benzidine  occur when  worst
     concentration   sludges  are  dumped  at  typical or  worst  sites  (see
     Index  1).

     Slight increases of seawater  benzidine  concentrations  occur  after  a
     24-hour  dumping cycle  (see Index 2).

     No toxic  conditions to  aquatic life occur  due to  the  dumping  of
     benzidine-containing sludge (see Index 3).

     A potential exists  for  significant  human  health risk for the  case
     of worst  seafood  consumption  from  organisms  exposed  to  the  worst
     benzidine   concnetrations  dumped at  the  worst and typical  disposal
     sites  (see Index 4).
                                   2-1

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                                SECTION 3

                 PRELIMINARY  HAZARD  INDICES  FOR BENZIDINE
                        IN MUNICIPAL SEWAGE  SLUDGE
I.   LANDSPREADING AND DISTRIBUTE ON-AND-MARKETING

     Based on  Che recommendations  of  Che experts  at the  OWES meetings
     (April-May,  1984),  an assessment of  this reuse/disposal  option is
     not  being  conducted  at  this  time.    EPA  reserves  the  right  to
     conduct such an assessment for this  option in the future.

II.  LANDFILLING

     Based on  the recommendations  of  the experCs  at the  OWRS meetings
     (April-May,  1984),  an assessment of  this reuse/disposal  option is
     not  being  conducted  at  this  time.    EPA  reserves  the  right  to
     conduct such an assessment for this  option in the future.

III. INCINERATION

     Based on  the recommendations  of  the experts  at the  OWRS meetings
     (April-May,  1984),  an assessmenC of  chis reuse/disposal  opcion is
     noC  being  conducted  at  this  time.    EPA  reserves  the  right  to
     conduct such an assessment for this  option in the future.
IV.  OCEAN DISPOSAL

     For  the  purpose  of  evaluating  pollutant   effects   upon  and/or
     subsequent uptake  by marine life  as a  result of  sludge  disposal,
     two types of  mixing  were modeled.   The  initial mixing  or dilution
     shortly after dumping of a single load of  sludge  represents a high,
     pulse  concentration  to •which  organisms may   be  exposed  for  short
     time periods  but which  could  be repeated  frequently;  i.e.,  every
     time a  recently dumped  plume  is encountered.   A  subsequent  addi-
     tional   degree  of mixing  can be  expressed by a  further  dilution.
     This is defined  as  the  average dilution  occurring  when a  day's
     worth of  sludge is  dispersed  by 24 hours  of current movement  and
     represents  the   time-weighted  average  exposure  concentration  for
     organisms in the disposal area.  This dilution accounts  for 8  to 12
     hours of  the high  pulse  concentration encountered  by  the  organisms
     during  'daylight disposal operations  and  12 to  16 hours  of recovery
     (ambient  water  concentration)  during  the   night when   disposal
     operations are suspended.

     A..   Index of Seawater Concentration  Resulting
          from Initial Mixing  of Sludge (Index 1)

          1.   Explanation - Calculates increased  concentrations  in  Ug/L
               of pollutant  in  seawater  around an  ocean disposal  site
               assuming initial  mixing.
                                   3-1

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2.   Assumptions/Limitations  -  Assumes  that  the  background
     seawater concentration  of pollutant  is unknown  or zero.
     The  index  also  assumes  that  disposal  is  by  tanker  and
     that  the  daily  amount  of  sludge  disposed  is  uniformly
     distributed  along  a   path   transversing   the  site  and
     perpendicular  to   the   current  vector.     The  initial
     dilution  volume  is  assumed   to  be   determined  by  path
     length,  depth  to  the  pycnocline  (a  layer  separating
     surface and  deeper water masses),  and an  initial  plume
     width  defined  as  the  width  of the  plume  4  hours  after
     dumping.  The  seasonal  disappearance  of the pycnocline is
     not considered.

3.   Data Used and Rationale

     a.   Disposal conditions

                     Sludge         Sludge Mass         Length
                     Disposal        Dumped by a       of Tanker
                     Rate (SS)    Single Tanker  (ST)   Path (L)

          Typical    825 mt DW/day    1600 mt WW         8000 m
          Worst      1650 mt DW/day    3400 mt WW         4000 m
          The typical value for  the  sludge  disposal  rate assumes
          that  7.5  x 10^  mt  WW/year  are available  for dumping
          from  a  metropolitan coastal  area.   The conversion  to
          dry weight  assumes  4  percent  solids  by  weight.   The
          worst-case  value  is  an  arbitrary  doubling-  of  the
          typical value  to allow for potential future increase.

          The assumed disposal  practice to be followed  at the
          model  site  representative  of the  typical  case  is  a
          modification of that proposed for  sludge disposal at
          the formally designated  12-mile site in the New York
          Bight  Apex  (City  of New York,  1983).   Sludge  barges
          with  capacities  of  .3400 mt  WW  would be required to
          discharge a load  in no less  than  53 minutes travel-
          ing at a  minimum  speed of 5 nautical miles  (9260 m)
          per hour.  Under  these conditions,  the  barge  would
          enter  the site, discharge  the sludge over  8180 m and
          exit  the  site.   Sludge  barges  with  capacities  of
          1600 mt WW would  be required to discharge  a load in
          no less than 32 minutes  traveling  at a minimum speed
          of  8  nautical  miles  (14,816 m)  per  hour.    Under
          these  conditions,  the  barge would  enter   the  site,
          discharge the  sludge  over 7902 m and exit  the site.
          The mean path length for the large  and  small tankers
          is 8041 m  or  approximately  8000 m.   Path   length is
          assumed  to  lie  perpendicular  to   the  direction  of
          prevailing  current  flow.  For  the  typical  disposal
          rate (SS) of 825  mt DW/day,  it  is  assumed  that  this
          would  be  accomplished  by  a  mixture of four 3400 mt
                         3-2

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     WW and four  1600  me  WW capacity barges.  The overall
     daily  disposal  operation  would  last   from  8  to  12
     hours.   For  the  worst-case  disposal  rate  (SS)  of
     1650 mt  DW/day,  eight 3400 mt  WW and  eight  1600  mt
     WW capacity  barges would  be  utilized.   The overall
     daily  disposal  operation  would  last   from  8  to  12
     hours.    For both  disposal  rate  scenarios,  there
     would be a 12 to  16  hour  period at  night in which no
     sludge would  be  dumped.   It  is assumed  that  under
     the   above   described  disposal  operation,   sludge
     dumping would occur every day of the year.

     The  assumed  disposal  practice  at  the  model  site
     representative  of the  worst  case  is  as  stated  for
     the typical site,  except  that  barges  would dump half
     their  load  along  a  track,  then  turn  around  and
     dispose of the  balance  along  the same  track in order
     to prevent a barge  from dumping outside of the site.
     This  practice  would   effectively   halve  the  path
     length compared  to the typical site.

b.   Sludge concentration of pollutant (SC)

     Worst    12.7 mg/kg DW

     Benzidine was detected  in only 1 percent  of  the  256
     publicly-owned   treatment   works   (POTWs)   surveyed
     throughout   the   United   States.      The   maximum
     concentration detected, 12.7  mg/kg  DW,  is  chosen  as
     the worst case;  no typical case is available.

c.   Disposal site characteristics

                                    Average
                                    current
                  Depth to          velocity
              pycnocline  (D)       at  site  (V)

     Typical      20  m             9500 m/day
     Worst         5  m             4-320 m/day
     Typical  site  values are  representative  of a  large,
     deep-water  site  with   an area  of  about  1500  km^
     located beyond the  continental shelf  in  the  New York
     Bight.   The pycnocline value  of  20 m chosen  is  the
     average  of  the  10  to  30 m  pycnocline  depth  range
     occurring  in  the  summer  and  fall;  the winter  and
     spring disappearance of the pycnocline is  not  consi-
     dered and  so  represents  a  conservative  approach  in
     evaluating  annual  or long-term impact.  The  current
     velocity of 11  cm/sec  (9500  m/day)  chosen is  based
     on the  average  current velocity  in this area  (CDM,
     1984b).
                    3-3

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     Worst-case values  are  representative of a near-shore
     New York  Bight site  with an  area  of  about  20 km^.
     The pycnocline value  of 5 m  chosen is  the  minimum
     value  of  the  5  to 23 m  depth range of  the  surface
     mixed  layer  and   is  therefore  a worst-case   value.
     Current  velocities  in  this  area   vary   from   0   to
     30 cm/sec.    A value  of  5 cm/sec  (4320 m/day)   is
     arbitrarily  chosen to  represent  a  worst-case   value
     (COM,  1984c).

Factors Considered in Initial Mixing

When a load  of sludge is dumped  from  a moving tanker,  an
immediate  mixing  occurs  in  the  turbulent  wake  of the
vessel, followed  by more gradual spreading  of the  plume.
.The  entire plume,  which initially constitutes a   narrow
band the length of  the  tanker path, moves more-or-less  as
a  unit with • the  prevailing  surface  current   and,   under
calm conditions,  is  not further  dispersed by  the  current
itself.  However,  the current acts  to separate successive
tanker loads,  moving each  out  of  .the  immediate  disposal
path before the next load is dumped.

Immediate   mixing   volume    after   barge   disposal    is
approximately  equal  to  the  length  of  the  dumping   track
with a cross-sectional  area  about four times' that  defined
by  the  draft  and  width   of   the  discharging    vessel
(Csanady,  1981,  as cited in  NOAA,  1983).   The resulting
plume  is  initially 10 m deep by 40 m wide  (O'Connor and
Park,  1982,   as   cited  in  NOAA,   1983).     Subsequent
spreading  of  plume band width  occurs  at  an average rate
of approximately  1  cm/sec  (Csanady  et  al.,  1979,  as   cited
in NOAA, 1983).   Vertical  mixing is limited by the   depth
of the pycnocline  or ocean  floor, whichever  is shallower.
Four hours after  disposal,  therefore,  average  plume  width
(W) may be  computed as follows:
                     *
W = 40 m +  1 cm/sec x 4 hours x  3600 sec/hour  x 0.01 m/cm
= 184 m = approximately 200 m

Thus  the  volume  of  initial  mixing  is  defined  by the
tanker path,  a 200 m  width,  and  a depth appropriate   to
the site.   For the typical (deep water)  site,  this  depth
is chosen as the  pycnocline value of 20 m.   For the  worst
(shallow water)  site,   a  value  of  10 m  was  chosen.   At
times the  pycnocline may be as shallow as 5 m, but  since
the barge  wake causes  initial  mixing to at  least  10 m,
the greater value was used.           >
                    3-4

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     5.   Index 1 Values (ug/L)
               Disposal                         Sludge Disposal
               Conditions and                   Rate (mt DW/day)
               Site Charac-     Sludge
               teristics    Concentration      0      825     1650
Typical
Worst
Worst
Worst
0.0
0.0
0.025
0.22
0.025
0.22
     6.   Value Interpretation - Value  equals  the expected increase
          in benzidine  concentration  in seawater around  a disposal
          site as a result of sludge disposal after initial mixing.

     6.   Preliminary Conclusion -

          Increases  in  seawater  concentration  of  benzidine  occur
          when  worst  concentration  sludges   are  dumped  at  the
          typical or worst sites.

B.   Index of Seawater Concentration  Representing a 24-Hour Dumping
     Cycle (Index 2)

     1.   Explanation - Calculates  increased concentrations  in Ug/L
          of pollutant  in  seawater around an  .ocean disposal  site
          utilizing  a  time  weighted average   (TWA)  concentration.
          The TWA  concentration  is  that which  would  be  experienced
          by an  organism  remaining  stationary  (with  respect  to the
          ocean  floor)   or  moving   randomly  within  the  disposal
          vicinity.   The  dilution  volume  is  determined  by  the
          tanker  path  length  and   depth  to  pycnocline  or for  the
          shallow  water-site,  the  10 m effective mixing  depth,  as
          before, but the effective width  is now determined by cur-
          rent movement  perpendicular  to  the  tanker path over  24
          hours.

     2.   As sumptions /Limitations - Incorporates  all  of  the assump-
          tions  used to  calculate. Index  1.    In  addition,  it  is
          assumed   that   organisms   would  experience   high-pulsed
          sludge concentrations  for 8 to 12  hours per day and then
          experience recovery  (no exposure to  sludge) for  12  to  16
          hours  per day.    This  situation can  be expressed by  the
          use of a TWA concentration of  sludge constituent.

     3.   Data Used and  Rationale

          See Section 3, pp. 3-2 to  3-4.
                              3-5

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     4.   Factors Considered  in  Determining  Subsequent  Additional
          Degree of  Mixing (Determination of TWA Concentrations)

          See Section 3,  p. 3-5.

     5.   Index 2 Values  (ug/L)
               Disposal                         Sludge Disposal
               Conditions and                   Rate (rot DW/day)
               Site Charac-    Sludge
               teristics    Concentration      0      825     1650
Typical
Worst
Worst
Worst
0.0
0.0
0.0069
0.061
0.014
0.12
     6.   Value  interpretation   -  Value   equals   the   effective
          increase   in  benzidine  concentration  expressed  as a  TWA
          concentration   in   seawater   around   a   disposal   site
          experienced by an organism over a 24-hour period.

     7.   Preliminary  Conclusion  - Slight  increases  of  seawater
          benzidine  concentrations occur  after  a 24-hour  dumping
          cycle.
C.   Index of Toxicity to Aquatic Life (Index 3)
          Explanation - Compares  the  effective  increased concentra-
          tion of  pollutant  in  seawater around  the disposal  site
          resulting  from  Che  initial mixing  of  sludge (Index  1)
          with the  marine  ambient  water quality  criterion of  the
          pollutant,  or  with  another  value judged  protective  of
          marine  aquatic  life.    For  benzidine,  this  value is  the
          criterion that will protect marine aquatic  organisms  from
          both acute and chronic toxic effects.

          Wherever a  short-term,  "pulse" exposure  may  occur as  it
          would from  initial  mixing,  it is usually  evaluated  using
          the  "maximum"   criteria  values  of  EPA's  ambient  water
          quality  criteria   methodology.     However,   under   this
          scenario,  because  the  pulse  is  repeated  several  times
          daily on  a long-term basis,  potentially resulting in  an
          accumulation of injury,  it  seems  more appropriate to  use
          values    designed    to   be  protective   against   chronic
          toxicity.    Therefore,   to   evaluate   the  potential   for
          adverse  effects   on  marine  life  resulting  from  initial
          mixing   concentrations,   as  quantified  by  Index  1,   the
          chronically derived criteria values are used.
                              3-6

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2.   Assumptions/Limitations -  In addition to  the assumptions
     stated  for  Indices  1  and  2,  assumes  that  all  of  the
     released  pollutant  is  available  in  the  water  column to
     move through predicted  pathways  (i.e.,  sludge to seawater
     to aquatic, organism  to  man).  The  possibility of  effects.
     arising  from accumulation in  the sediments  is  neglected
     since the  U.S.   EPA  presently  lacks  a satisfactory method
     for deriving sediment criteria.

3.   Data Used and Rationale

     a.   Concentration  of  pollutant  in  seawater  around  a
          disposal site (Index 1)

          See Section 3, p. 3-5.

     b.   Ambient water quality criterion (AWQC) = 2,500 pg/L

          Water  quality  criteria  for •the  toxic  pollutants
          listed  under  Section  307(a)(l)  of  the  Clean  Water
          Act  of 1977  were  developed  by  the  U.S.  EPA  under
          Section 30A(a)(l)  of  the  Act.   These  criteria  were
          derived  by   utilization   of  data   reflecting   the
          resultant  environmental  impacts  and  human  ^health
          effects of  these pollutants  if  present  in any  body
          of  water.    The criteria  values  presented in  this
          assessment  are  excerpted  from  the .ambient  water
          quality criteria document  for benzidine.

          Toxicity to freshwater  fish  and  invertebrates  occurs
          at  the above  concentration  of  benzidine  and  would
          occur  at  lower  concentrations  among organisms  more
          sensitive  than  those tested  (U.S.  EPA,  1980).    As
          not  data  are available  on marine  organisms,  it  is
          assumed for  the purpose  of  this  study  that  values
          are  similar  for both  freshwater and marine  aquatic
          life.

4.   Index 3 Values
          Disposal                           Sludge Disposal
          Conditions and                     Rate (mt DW/day)
          Site Charac-    Sludge
teristics
Typical
Worst
Concentration
Worst
Worst
0
0
0
.0
.0

0
0
825
.000010
.000086

0
0
1650
.000010
.000086
                         3-7

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     5.   Value Interpretation  - Value  equals  Che factor  by which
          the expected  seawater  concentration increase in benzidine
          exceeds  the protective value.   A value  > 1  indicates that
          acute or chronic  toxic conditions  may exist for organisms
          at the site.

     6.   Preliminary Conclusion - No  toxic  conditions occur due to
          the dumping of benzidine-containing sludge.

D.   Index of Human  Cancer Risk Resulting  from Seafood Consumption
     (Index 4)

     1.   Explanation - Estimates  the  expected  increase  in  human
          pollutant  intake  associated   with  the  consumption  of
          seafood, a fraction of which originates from the disposal
          site vicinity,  and  compares  the total  expected pollutant
          intake with the  cancer risk-specific intake  (RSI)  of the
          pollutant.

     2.   Assumptions/Limitations -  In addition  to the assumptions
          listed  for Indices  1 and  2,  assumes  that the  seafood
          tissue  concentration  increase  can  be estimated  from the
          increased   water   concentration    (Index    2)    by   a
          bioconcentration factor.   It also  assumes  that,  over the
          long  term,  the  seafood   catch from   the  disposal  site
          vicinity will be diluted to  some extent by  the  catch from
          uncontaminated areas.

     3.   Data Used and Rationale

          a.   Concentration  of  pollutant  in  seawater  around  a
               disposal site (Index 2)

               See Section 3,  p. 3-6.

               Since   biconcentration  is  a  dynamic  and  reversible
               process,   it  is  expected that   uptake  of  sludge
               pollutants by marine  organisms at  the  disposal  site
               will  reflect  TWA  concentrations,   as  quantified  by
               Index  2,  rather than pulse concentrations.

          b.   Dietary consumption of seafood (QF)

               Typical     .14.3  g WW/day
               Worst        41.7  g WW/day

               Typical  and  worst-case  values are  the mean and  the
               95th  percentile,   respectively,   for    all   seafood
               consumption in the  United States  (Stanford  Research
               Institute (SRI) International, 1980).
                              3-8

-------
Fraction  of  consumed  seafood  originating  from  the
disposal site (PS)

For  a typical  harvesting  scenario,  it  was assumed
that  the  total  catch over a wide  region  is mixed by
harvesting, marketing  and consumption practices,  and
that  exposure  is  thereby  diluted.    Coastal  areas
have  been  divided   by  the  National  Marine Fishery
Service (NMFS)  into  reporting  areas for reporting on
data   on   seafood   landings.     Therefore   it   was
convenient  to  express  the  total  area  affected  by
sludge disposal  as   a  fraction of  an  NMFS  reporting
area-    The  area  used   to  represent  the  disposal
impact area  should  be  an approximation of the total
ocean  area  over  which  the  average  concentration
defined  by  Index  2  is  roughly   applicable.     The
average rate  of  plume  spreading  of 1 cm/sec referred
to  earlier   amounts  to   approximately  0.9 km/day.
Therefore,  the  "combined  plume  of  all  sludge  dumped
during one  working   day  will gradually spread,  both
parallel  to  and perpendicular to  current direction,
as    it    proceeds    down-current.       Since    the
concentration has  been averaged  over  the direction
of  current  flow,  spreading in  this, dimension  will
not   further   reduce  average   concentration;   only
spreading in  the perpendicular dimension  will  reduce
the average.   If stable  conditions are assumed over
a period  of  days,  at least 9  days  would  be required
to reduce the average  concentration by  one-half.  At
that   time,    the    original   plume    length   of
approximately  8 km  (8000 m)  will  have  doubled  to
approximately 16 km due to spreading.

It  is  probably  unnecessary  to  follow  the  plume
further  since  storms,  which  would  result  in  much
more  rapid  dispersion  of  pollutants   to  background
concentrations  are   expected  on  at  least   a  10-day
frequency   (NOAA,   1983).     Therefore,    the   area
impacted  by  sludge  disposal  (AI,  in  km2) at  each
disposal  site will   be  considered  to  be   defined  by
the  tanker  path  length  (L)  times  the  distance  of
current movement (V) during  10 days,  and  is computed
as follows:

     AI = 10 x L x V x 10~6 km2/m2         .  (1)

To be  consistent with  a conservative  approach,  plume
dilution  due   to  spreading   in   the  perpendicular
direction  to current  flow  is  disregarded.    More
likely, organisms exposed to  the  plume in  the  area
defined by equation  1 would  experience  a  TWA. concen-
tration  lower than  the  concentration  expressed  by
Index 2.

               3-9

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       Next,   the  value  of  AI  must  be  expressed  as  a
       fraction of an NMFS reporting  area.   In the New York
       Bight,  which  includes  NMFS  areas  612-616 and  621-
       623,   deep-water   area   623   has   an   area   of
       approximately 7200 km2  and  constitutes  approximately
       0.02 percent of  the  total  seafood landings  for  the
       Bight  (CDM, 1984a).'  Near-shore  area  612  has  an area
       of   approximately    4300   km2    and    constitutes
       approximately  24 percent  of   the  total   seafood
       landings  (CDM,  1984b).   Therefore  the  fraction  of
       all  seafood  landings   (FSt)   from the  Bight  which
       could  originate  from  the area  of  impact  of  either
       the typical  (deep-water)  or worst  (near-shore)  site
       can  be   calculated   for  this   typical   harvesting
       scenario as follows:

       For the  typical  (deep water)  site:

           = AI x 0.02% =                                (2)
         t   7200 km^

[10 x 8000 m x 9500 m x  10"6  km2/m2]  x 0.0002              5
                           A                    ~~ ^ • X  X J. U
                    7200 km2                        .    .

       For the  worst (near  shore) site:

       FSt = ^-J
             4300 km2

  [10 x 4000 m x 4320 m. x 10"6 km2/m2]  x 0.24  _           3
                                               2—  y • u  x i u
                   T^VW ~»

       To  construct  a  worst-case  harvesting  scenario,   it
       was assumed  that  the  total  seafood consumption  for
       an  individual  could  originate   from  an  area more
       limited   than  the  entire  New   York   Bight.     For
       example,  a particular fisherman  providing  the  entire
       seafood   diet  for  himself  or   others   could fish
       habitually within a single NMFS  reporting  area.   Or,
       an  individual   could   have   a   preference   for   a
       particular species which  is  taken  only over   a more
       limited  area, here  assumed arbitrarily  to equal  an
       NMFS  reporting   area.     The   fraction   of consumed
       seafood  (FSW) that could  originate from the area  of
       impact  under this worst-case  scenario  is  calculated
       as follows:

       For the  typical  (deep  water)  site:

       FSW = 	AI  0   = 0.11                       (4)
             7200 km2
                     3-10

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For the worst (near shore) -site:

      - ^— -
      4300 km2
     FSW = -  — - = O.OAO                       (5)
d.   Bioconcentration   factor   of    pollutant   (BCF)   =
     87.5 L/kg

     The  value  chosen  is  the  weighted  average  BCF  of
     benzidine  for  the edible  portion of  all  freshwater
     and  estuarine  aquatic   organisms  consumed  by  U.S.
     citizens  (U.S. EPA,  1980).   The  weighted averate BCF
     is  derived as  part   of  the water quality  criteria
     developed  by  the  U.S.  EPA  to  protect  human  health
     from the  potential carcinogenic  effects  of benzidine
     induced   by  ingestion   of   contaminated  water  and
     aquatic  organisms.   The   weighted  average  BCF  is
     calculated  by  adjusting  the   mean  normalized  BCF
     (steady-state  BCF   corrected  to  1   percent   lipid
     content)  to the  3  percent  lipid  content  of  consumed
     fish and  shellfish.   It  should  be  noted  that  lipids
     of  marine  species  differ  in  both  structure  and
     quantity  from those  of freshwater species.   Although
     a  BCF   value  calculated  entirely  from  marine  data
     would  be  more  appropriate  for  this   assessment,  no
     such data are presently available.

e.   Average daily human  dietary intake  of pollutant (DI)
     = 0 ug/day

     Although  no data  are immediately available on  DI ,  a
     value  of  0 ug/day is assumed so that  index  values
     can be calculated*

f.   Cancer potency = 234  (mg/kg/day)~^

     The  cancer potency  value  is  derived by  U.S.  EPA
     (1980)  based on studies  of bladder cancer in  humans.

g.   Cancer risk— specific  intake (RSI) =
     2.99 x 10~4 Ug/day

     The RSI is  the  pollutant intake  value which  results
     in  an  increase  in   cancer risk  of  10~°   (1  per
     1,000,000).   The  RSI is  calculated from  the  cancer
     potency using the following formula:

         _  IP"6 x 70 kg x 103 Ug/mg
                   Cancer  potency
                   3-11

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4.   Index 4 Values

     Disposal                                  Sludge Disposal
     Conditions and                            Rate (mt DW/day)
     Site Charac-      Sludge      Seafood
     teristics     Concentration3  Intakea»b  0      825    1650

     Typical       Worst         Typical     0.0   0.00061  0.0012
                                 Worst       0.0   9.3     18

     Worst         Worst         Typical     0.0   2.4      4.9
                                 Worst       0.0  30.0     59
     a All  possible  combinations  of  these  values  are  not
       presented.   Additional  combinations  may  be  calculated
       using the formulae in the Appendix.

     0 Refers to both  the  dietary consumption  of  seafood (QF)
       and  the  fraction of  consumed seafood  originating from
       the disposal site (FS).   "Typical" indicates  the use of
       the  typical-case  values  for  both  of  these  parameters;
       "worst" indicates the  use of the  worst-case  values for
       both.

     Value  Interpretation  -  Value  >  1  indicates a  potential
     increase  in -cancer  risk  of >  10~6  (1  per  1,000,000).
     Comparison  with   the   null  index  value   at   0  mt/day
     indicates the degree to  which any hazard is  due to sludge
     disposal, as opposed to pre-existing  dietary sources.

     Preliminary   Conclusion   -  A   potential   exists   for
     significant  human  health  risk for the  case  of  worst
     seafood  consumption  from organisms  exposed  to  the  worst
     benzidine concentrations  dumped  at  the  worst and typical
     sites.
                        3-12

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                              SECTION 4

  PRELIMINARY DATA PROFILE FOR BENZIDINE IN MUNICIPAL SEWAGE SLUDGE
I. OCCURRENCE

   Benzidine and its congeners  are used in the  industry  primarily for
   the synthesis  of azo  dyes.    U.S.   production,  and importation  of
   benzidine and benzidine  compounds  may exceed 3.5  million kilograms
   per  year.    Benzidine  and   its  derivatives   are  not  naturally
   occurring compounds  and  are  not thought  to be  generally dispersed
   in the environment.
A.  Sludge

    1.  Frequency of Detection

        Benzidine not detected in influent,
        effluent, or sludges from 50 POTWs

        Benzidine detected in 1 percent of
        256 POTWs studied

    2.  Concentration

        Maximum value 12.7 yg/g DW in
        256 POTWs studied

B.  Soil - Unpolluted

    "No data were found concerning the
    distribution of benzidine compounds in
    soil.  Benzidine has been shown to be
    absorbed to some clays and, because of
    its physical properties, is probably
    immobilized rapidly in soils and sediments."

C.  Water - Unpolluted

    In the United States, benzidine and its
    derivatives have been observed in
    dye manufacturing factory wastes, but
    not in the drainage areas into which these
    wastes feed; however, few attempts at
    actual measurements have been made.

    Benzidine has not been found to occur in
    the aquatic environment in the U.S.
                                                      U.S. EPA, 1982a
                                                      (p.  36-50)

                                                      COM, 1984c
                                                      (p.  8)
                                                      CDM,  1984c
                                                      (p.  8)
                                                      U.S.  EPA,  1978
                                                      (p.  4)
                                                      U.S.  EPA,  1978
                                                      (p. 4)
                                                     U.S.  EPA,  1978
                                                     (p.  79)
                                4-1

-------
        A field survey of the Buffalo and Niagara      U.S. EPA, 1980
        River using the chloraraine-T method            (p. C-27)
        (method is suspect) detected as no benzidine
        positive samples (Detection Limit = 0.2 ug/L).
    D.  Air
        No measurements for benzidine in ambient       U.S. EPA, 1979
        air have been reported.                        (p. 10)

    E.  Pood

        Ingestion is not generally an important        U.S. EPA, 1980
        source of exposure to benzidine.               (p. C-l)

        No data on benzidine in food were found.

II. HUMAN EFFECTS

    A.  Ingestion

        1.  Carcinogenicity

            a.  Qualitative Assessment

                Data not immediately available.

            b.  Potency

                Cancer potency = 234                   U.S. EPA, 1980
                (mg/kg/dayr1    '                      (p. C-54)

            c.  Effects

                Data not immediately available.

        2.  Chronic Toxicity

            Data not immediately available.

    B.  Inhalation

        1.  Carcinogenicity

            a.  Qualitative Assessment

                Data show that benzidine is  a human     U.S. EPA, 1980
                carcinogen.

            b.  Potency

                Cancer potency = 234                   U.S. EPA, 1980
                (mg/kg/dayr1    .           -           (p.  C-54)
                                  4-2

-------
             c.  Effects

                 Benzidine and its derivatives have     U.S. EPA, 1980
               '  been shown to produce bladder          (p. C-15)
                 cancer after a long period of
                 latency.

         2.  Chronic Toxicity

             Data not immediately available.

III. PLANT EFFECTS

     No data are  available on benzidine metabolism      U.S. EPA, 1978
     or effects from benzidine exposure in higher       (p. 6)
     plants.  Benzidine has not received much
     attention in this area since it is not a natural
     environmental constituent and is not believed
     to be widely dispersed from industrial sources.

 IV. DOMESTIC ANIMAL AND WILDLIFE EFFECTS

     A.  Toxicity

         Rats fed N,N'-diacetylbenzidine and            U.S. EPA, 1978
         N, N, N1,N'-tetramethylbenzidine at            (p. 101)
         equal molar levels of 0.25% and 0.27%
         respectively, developed, lipemia and
         glomerular lesions consisting of fat-
         filled spaces in the glomerular tuft
         2 to 4.5  months after beginning of
         treatment.

         Mice fed 0.01%-0.08% benzidine                 U.S. EPA, 1978
         dihydrochloride exhi-bited various toxic         (p. 101)
         symptoms:  lost weight in proportion to
         the dose  of benzidine received, decreased
         weight of liver and kidney with increased
         dosage,  increased thymus weight with
         increased dosage.

         Subcutaneous injection of benzidine has         U.S. EPA, 1978
         produced  cancer in mice and rats.              (p. 102)

         Rats fed  0.043% N,N'-diacetylbenzidine          U.S. EPA, 1980
         developed glomerulonephritis and               (p. C-12)
         nephrotic syndrome.

         Orally administered  benzidine did not          U.S.  EPA, 1980
         produce  urinary bladder cancer in dogs.         (p.  C-17)
         No tumors were found in female beagle dogs
         fed 1 rag/kg,  5 days  per week for 3 years.
                                  4-3

-------
        In hamsters fed benzidine in 0.1% of their     U.S. EPA, 1980
        diet throughout their life span, extensive     (p. C-17)
        bile duct proliferations and cysts appeared
        along with cholangiofibrosis, hepatomas, and
        liver cell carcinoma.

        It is the metabolites of benzidine that        U.S. EPA, 1980
        are considered to be the proximate             (p. C-17)
        carcinogens.

        Benzidine and its salts, without question,     U.S. EPA, 1979
        are carcinogenic to humans,  with the site      (p. 11)
        of tumor induction being the bladder.

    B.  Uptake

        Benzidine does not appear to be stored or      From data
        concentrated in animal tissue, but is          presented in
        metabolized, with metabolites and free         U.S. EPA, 1980
        benzidine eliminated in urine (primarily)      (p. C-4 to
        and feces.                                     C-ll)

V.  AQUATIC LIFE EFFECTS

    A.  Toxicity (Water concentration causing)

        1.  Freshwater

            Acute toxicity occurs at concen-           U.S. EPA, 1980
            trations as low as 2500  Ug/L.     _.       (p. B-2)
            Based on tests of one invertebrate
            and five fish species.

        2.  Saltwater

            Data not immediately available.

    B.  Uptake

        Bioconcentration factor = 87.5 L/kg

        Based on the edible portion  of all             U.S. EPA, 1980
        freshwater and estuarine aquatic               (p. C-3)
        organisms consumed by U.S. citizens.


VI. SOIL BIOTA EFFECTS

    Benzidine inhibited biooxidation in activated      U.S. EPA, 1978
    sludges at 500 mg/L,  caused some inhibition         (p. 74)
    at 1 to 5 mg/L,  and was thought  to be oxidized
    at 0.1 mg/L or less.
                                  4-4

-------
VII. PHYSICOCHEMICAL DATA FOR ESTIMATING FATE AND TRANSPORT

     Molecular weight:   184.23
     Density:   1.250
     Melting point:   115° to 120°C (slow heating)
                  128°C (fast heating)
     Boiling point:   400°C
     Soluble in alcohol and ether
     Slightly soluble in water:   400 mg/L (12°C)

     Under experimental water waste treatment           U.S. EPA, 1978
     conditions, air oxidation of benzidine             (p. 5)
     proceeded readily, and there was also some
     evidence of biological oxidation.

     Chemical  f-ormula:

     Benzidine is apparently not easily degraded      .  U.S."EPA, 1980
     by the microorganisms in sewage plant sludge       (p. A-2)

     Benzidine half  life in water is estimated at       U.S. EPA, 1980
     100 days                                            (p. C-27)
                                   4-5

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                                SECTION 5

                                REFERENCES
Camp Dresser  and  McKee,  Inc.   1984a.   Technical  Review  of  the 106-Mile
     Ocean Disposal Site.   Prepared for U.S.  EPA  under  Contract No. 68-
     01-6403.  Annandale, VA.  January.

Camp Dresser  and  McKee,  Inc.   1984b.   Technical  Review of  the 12-Mile
     Sewage Sludge Disposal  Site.   Prepared for U.S.  EPA under Contract
     No. 68-01-6403.   Annandale, VA.  May.

Camp Dresser  and  McKee,  Inc.   1984c.   A Comparison of  Studies of Toxic
     Substances in POTW  Sludges.   .Prepared  for U.S.  EPA under Contract
     No. 68-01-6403.   Annandale, VA.  August.

City of New  York Department  of  Environmental Protection.    1983.   A
     Special  Permit Application for the  Disposal  of  Sewage  Sludge from
     Twelve New York.  City  Pollution Control Plants at 'the  12-Mile Site.
     New York, NY.  December.

NOAA Technical  Memorandum NMFS-F  NEC-26.    1983.   Northeast  Monitoring
     Program  106-Mile  Site  Characterization  Update.   U.S.  Department  of
     Commerce National Oceanic and Atmospheric Administration.  August.

Stanford Research  Institute International.   1980.  Seafood  Consumption
     Data Analysis.  Final Report,  Task  11.   Prepared  for U.S.  EPA under
     Contract No.   68-01-3887.  Menlo Park, California, September.

U.S.  Environmental   Protection  Agency.      1978.     Reviews  of   the
     Environmental Effects  of  Pollutants.    II.    Benzidine.   EPA-600/1-
     78-024.  Cincinnati, Ohio.

U.S. Environmental Protection Agency.  1979.   Status Assessment of Toxic
     Chemicals.  Benzidine.   EPA-600/2-79-210e.  Cincinnati,  Ohio.

U.S. Environmental  Protection  Agency.   1980.    Ambient Water  Quality
     Criteria for  Benzidine.  EPA 440/5-80-023.  Washington,  D.C.

U.S.  Environmental  Protection  Agency.     1982a.     Fate   of   Priority
     Pollutants in  Publicly-Owned  Treatment  Works.    Volume   1.    EPA
     440/1-82/303.  Washington, D.C.

U.S.  Environmental  Protection  Agency.     1982b.     Test   Methods  for
     Evaluating Solid  Waste.  SW-846.  Washington,  D.C.                 ^
                                   5-1

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                                 APPENDIX

                PRELIMINARY HAZARD INDEX CALCULATIONS FOR
                   BENZIDINE  IN MUNICIPAL SEWAGE SLUDGE
  I. LANDSPREADING AND DISTRIBUTION-AND-MARKETING

     Based on  the recommendations  of the  experts at  the  OWRS meetings
     (April-May,  1984),  an assessment  of this  reuse/disposal  option  is
     not  being  conducted  at  this  time.   EPA reserves  the  right   to
     conduct such as assessment for this option  in the  future.

II.  LANDFILLING

     Based on  the recommendations  of the  experts at  the  OWRS meetings
     (April-May,  1984),  an assessment  of this  reuse/disposal  option  is
     not  being  conducted  at  this  time.   EPA reserves  the  right   to
     conduct such as assessment for this option  in the  future.

III. INCINERATION

     Based on  the recommendations  of the  experts  at  the  OWRS meetings
     (April-May,  1984),  an assessment  of this  reuse/disposal  option  is
     not  being  conducted  at  this  time.   EPA reserves  the  right   to
     conduct such as assessment for this option  in the  future.

IV.  OCEAN DISPOSAL
     A.   Index of  Seawater  Concentration Resulting  from  Initial Mixing
          of Sludge (Index 1)

          1.   Formula

                          SC x ST x PS
               Index 1 =
                           W x D x L

               where:

                    SC = Sludge concentration of pollutant (mg/kg DW)
                    ST = Sludge mass dumped by a single tanker (kg WW)
                    PS = Percent solids in sludge (kg DW/kg WW)
                    W  = Width of initial plume dilution (m)
                    D  = Depth  to  pycnocline   or   effective   depth  of
                         mixing for shallow water site (m)
                    L  = Length of tanker path (m)

          2.   Sample Calculation

             12.7 mg/kgDW x 1600000 kg WW x 0.04  kg  DW/kg  WW x 103  ug/mg
             - — - -   - — *            -a
n
0.                                                  ,
                         200 m x 20 m x 8000 m  x  103  L/m3
                                   A-l

-------
B.   Index of Seawater  Concentration Representing a 24-hour  Dumping
     Cycle.  (Index 2)

     1.   Formula

                     SS x SC
          Index 2 =
               V x D x L

     where:

          SS = Daily sludge disposal rate (kg DW/day)
          SC = Sludge concentration of pollutant (mg/kg DW)
          V  = Average current velocity at site (m/day)
          D  = Depth  to   pycnocline   or   effective  depth  of
               mixing for shallow water site (m)
          L  = Length of tanker path (m)

2.   Sample Calculation

        ,,  /T - 825000 kg DW/day x  12.7  mg/kg  DW x 103 Ug/mg
        ug/L -                                     ->   '-*
                        9500 m/day x 20 m x  8000  m x 10->

C.   Index of Toxicity to Aquatic Life (Index 3)

     1.   Formula


          IndeX 3 = ATJQC"

          where:

            I± =  Index 1 = Index of seawater concentration
                  resulting   from  initial   mixing   after   sludge
                  disposal (ug/L)
          AWQC =  Criterion or other value expressed as an average
                  concentration  to protect  marine  organisms  from
                  acute and chronic toxic effects (ug/L)

     2.   Sample Calculation

              O.OOOOiO
D.   Index of Human  Cancer Risk Resulting  from Seafood Consumption
     (Index 4)

     1.   Formula

          _ ,    .     (I2  x BCF x 10~3 kg/g x FS x QP) + PI
          Index 4 = - RSI
                              A-2

-------
               where:

               12  =   Index 2 = Index of  seawater concentration
                       representing a 24-hour dumping cycle  (ug/L)
               QF  =   Dietary consumption of seafood (g  WW/day)
               FS  =   Fraction of  consumed seafood originating  from the
                       disposal site (unitless)
               BCF =   Bioconcentration factor of pollutant  (L/kg)
               DI  =   Average daily human dietary intake of pollutant
                       (Ug/day)
               RSI =   Cancer risk-specific intake (ug/day)

          2.   Sample Calculation

   0.00061 =

(0.0069ug/L x 87.5L/kg x 10~3kg/g x O.OQ0021 x 14.3gWW/day) * Oug/dav
                                2.99 x 10"* Ug/day
                                  A-3

-------