-------
  a
 •H


  O
  r)
  O


• fi
  U
IT)


(N
                0)
                -P
                flj



                10
                     \^      i  i
                     ig      -a
rl
4J
0)
s
g
Prob
tn
0)
><
                                                1
                                                        ft
                                          81
•H

is       a
 a)       if
•H   (1)   (3
MH   tn  H
•H   (d
 u  ;C    .
 tu   ft  ft
 ft      id
 W   rl   >
     o
4-1   ft   •
 o      as
                                                  0
                                                  H
                                                  n
                                                                        o
                                                                        o
•o
 tu
-H
MH
•H
 U
 0)
 ft
 w

4-1
 O
                                                                                 o
                                                                                 2
                                                                                                                 tn
                                                                                                                 C
                                                                                                                 •H
                                                                                                                 4-1
                                                                                                              I   4-1
                                                                                                             (1)  W
                                                                                                 t{
                                                                                                 3
                                                                                                 •O
                                                                                                 O
                                                                                                       (fl
                                                                                                      -H
                                                                                                                 0)
                                                                                                             ft 4-1   0)
                                                                                                                 O  4-1
                                                                                                             O  (1)   fi!
                                                                                                             3  4J   g
ro

 Q)
H

•3
EH


















•.
0

_
**
^
w
(N)
*
i£>
^
*^J*
•.
CN
















0)
i
tn










rH
>1
c
Q)
.c
ft
•rl
A
O
SH
0
H
fi
O
X
0)
.c




*
•o
c
3
O
ft
g
0
CJ





































•
Cn
BC



a

fo
rH

•
a
r?

»
Cr*
tc


tu
u
rl
3
0


r^
(d
J^
M
H










P
^

O
rH
r")










|

O
rH
ro




X
5*

^i
tn
S

CH
w









•
M


o
o
rH









•
rl

0
o
rH



(U
-rj
EH

•
rrj
(d
rl

t-H






tn
•



















tn
0)
>H
c
o
•H
4-i tn
fi 0
•H 3
JH T3
O O
rH S-l
fi ft
O
Q)
Q



T3
§

O
M
0
H
r^
U
(d
4->
ft
(U
W


O
rl
O
rH
,c
o
m
4-)
ft
tu
fi

£
<5J

C
0
•H
(d
w
•H
rl
0)
g
o
tn
M




•a
0)
g
0 fi
SH O
O MH
rH
fi tn
U M
td tu
4-> g
o o
o tn
•H

•a
0)
4J
u
0)
4J
0)
•o

r4
a)
g
o
01
H



tn
u
3

O

ft



                                                                                                              C
                                                                                                              (1)
                                                                                                             8
                                                                                                                   to

                                                                                                                   rl
                                                                                                                   Q)
                                                                                                                   O
                                                                                                                   ft

                                                                                                                   r!
                                                                                                                   O
                                                                                                                                  0)

                                                                                                                                  W

                                                                                                                                  0)

                                                                                                                                  rl

                                                                                                                                  ft
                                                                                                                                 •8
                                                                                                                                  rl
                                                                                                                                  a
                                                                                                                                  x
                                                                                                                                  o
                                                                                                                                  rl

                                                                                                                                  0
                                                                                                                    X
                                                                                                                    o
                                                                                                                   •s
                                                                                                                    
-------
    >f
    c
    Q)
    ,C
    a
    o
    H
-   O
-   u
CN       "d
c     ft
a)     e
U)     D
(I)

PU     O
       C
  CN   O
O     U
                                        OJ
                                        U
 0
U)

•s
a
s

£r>

g
w
                                                       0)
                                                       g
                                                      •H
                                    1
                                    in
                                    H
                                                              §
                                                             -H
 C
-H  W
 tl  I 1
 O  U

3-d
 u  o

S  ft
                                                                                              EG
                                                                            s?
                                                                            o

                                                                           •8
                                                                            (d
                                                                           u
                                                                            o
                                                                           2
                                            47
-------
In spite of the qualitative nature of these investigations,  some genera-
lizations can be drawn concerning the mechanisms operative in the photo-
chemistry of PCBs.   Irradiations of individual isomers generally yielded
mechanistically interpretable products while irradiations of the complex
commercial mixtures could only be roughly characterized.

Although as previously noted, rates and percent disappearance of the
isomers are not comparable between experimenters due to lack of quanti-
fication of light fluxes; experiments conducted with a common light
source are useful.   When this was the case, rates of disappearance of PCB
mixtures were found to differ according to the solvent used(147).  irradia-
tion of 2 ppm of 54% chlorinated biphenyl mixtures were found to disappear
at decreasing rates in the order:  hexane, water, and benzene^1*^.  This
order is believed to be related to the ability of the biphenyl radical to
abstract a hydrogen from the solvent.  This order is an anomaly since water
has the highest H bond energy of any of the three.  The insolubility of
PCBs in water may contribute to an apparent removal.

The number of chlorines and the position of the chlorines on the biphenyl
structure are expected to have an effect on the rate of disappearance.  It
is expected that due to steric effect, the ortho substituted compounds
should eliminate the ortho chlorine faster than the corresponding non-
ortho compound.  However, upon irradiation at 310 nanometers for 24 hours,
the following isomers in hexane (1000 ppm) were still present at the
indicated percentages: 3, 4, 3', 4'-tetrachlorobiphenyl - 32%, 2, 6, 2',
6'-tetrachlorobiphenyl - 29%, 2, 5, 2', 5'-tetrachlorobiphenyl - 33%,
2, 4, 5, 2', 4', 5'-hexachlorobiphenyl - 3.8%, and 2, 3,  4,  5, 2', 3',
4', 5'-octachlorobiphenyl - 1%(**°).  Thus, the only distinguishable
effects are that the higher chlorinated compounds tend to degrade more
efficiently.  The effect of the position on the ring is not apparent.

The most frequently observed result of irradiation of PCB mixtures or
individual isomers is stepwise dechlorination.  The removal of chlorines
is seen in different solvents with both sunlight and 310 nanometer mer-
cury vapor light.  Dechlorination, for example, occurred upon irradiation
of 2, 4, 6, 2', 4', 6'-hexachlorobiphenyl in hexane where penta, tetra,
trik di and monochlorobiphenyls in addition to biphenyl were formed(^  ).

Dechlorination is observed along with  isomerization and chlorination in
situations where one or less hydrogens are available for abstraction from
the solvent and no other species are present to react with the dissociated
components of the biphenyl.  This situation occurs when PCBs are irradi-
ated as pure solids or in degassed solvents such as a chlorofluorocarbon.
In this environment the phenyl radical and the chlorine atom have no
choice but to recombine or react with other PCB molecules.  Thus dechlori-
nation and chlorination occur leading to  isomerization.

Under prolonged irradiation  (90-100 hours) polymers are formed even at
concentrations as low as 10 ppm^^^J.  Since chlorination and dechlori-
nation products can again participate in  the same dissociation processes

                                       48
-------
the biphenyl radical can be regenerated,

    1)   ClvPh Ph C1  + hv+ Clv Ph Ph C1Y ,  + Cl'      (dissociation)
           A.        A.         •"•         A."" JL
    2)   Clx Ph Ph Clx_]_ + Cl- -»- Clx Ph Ph Clx         (recombination)
    3)   Clx Ph Ph Clx + Cl(+H)cix Ph Ph Clx+1         (chlorination)
    4)   Clx Ph Ph-Cl.^} 4 A •> Clx Ph Ph C1X-1A        (Radical Fraction)

         A = Reactant e.g. H, 02, NO, €'tc.

Thus the products of these reactions may still be able to further under-
go photochemical reactions.  But polymerization reactions may also be
competing.

    5)   2 Clx Ph Ph-Cl^} •»• Clx Ph Ph (Clx_j) (Clx)Ph Rh (Cl^)

In most of the irradiations where oxygen was not removed from the solvent
oxygenated products were observed.  These were roughly characterized by
thin layer chromatographic techniques as being hydroxy and carboxy
compounds.  When one group of investigators  irradiated in methanol they
detected 80 compounds via gc/ms(   ).  Most  of the products were oxygen-
ated chloroaromatics - among them a series of methoxy substituted
chlorodibenzofurans with 1-5 chlorines and a series of p-methoxy PCBs.

Recent studies have centered upon the nature cf the excited electronic
states, the mechanisms and the rates of different PCB isomers of the
same chlorine content.  Nordblum and Miller  irradiated 4,4'=dichloro-
biphenyl at 310 nanometers in a variety of organic solvents(150).  When
the 4,4'-dichlorobiphenyl was irradiated in both degassed methanol and
2-propanol, 4-chlorobiphenyl and hydrogen chloride were formed in
quantitative yield.  The new hydrogen on the 4-chlorobiphenyl was abstia* -
ted from the methyl of the methanol as determined by using deuterated
methanol.  This implies a typical free radical reaction where the weaker
C-H bond is broken in preference to the OH bond.  Consistent with similar
studies it was found that the rate of reactant disappearance was slowed
by the presence of oxygen and the product mixture was complex.

The second of the recent studies by Ruzo, Zabik, and Schuetz is a
systematic study of the rates and medianisms of the photo recution of
6 tetrachloro biphenyl isomers^    '   '.  Again, irradiations at 310
nanometers in both hexane and methanol produced hydrogen chloride,
dechlorination products accounting for 90 -  95% of the reacted starting
material and between 1 and 3% methoxy substituted biphenyls in the case
of the methanolic solutions.  The PCBs studied are summarized below.

         PCB                                       Designation

3,4,3',4' - tetrachlorobiphenyl                        I
2,4,2',4' - tetrachlorobiphenyl                        II
3,4,3',4' - tetrachlorobiphenyl                        III

                                    49
-------
2,3,2',3'  - tetrachlorobiphenyl                        IV
2,5,2',5'  - tetrachlorobiphenyl                        V
2,6,2',6'  - tetrachlorobiphenyl                        VI

The products formed after 20 hours irradiation in hexane and methanol
are tabulated below:

PCB      Dechlorinated Product                Methoxylated Products

I        3,4,4' - trichlorobiphenyl           trichloromethoxy biphenyl
         4,4'   - dichlorobiphenyl
II       2,4,4' - trichlorobiphenyl           trichloromethroxybiphenyl
         4,4'   - dichlorobiphenyl            dichloromethroxybiphenyl
         4      - chlorobiphenyl
III      3,5,3' - trichlorobiphenyl
IV       2,3,3' - trichlorobiphenyl           trichloromethoxybiphenyl
         2,3,2' - trichlorobiphenyl           dichlorodimethoxybiphenyl
         3,3'   - dichlorobiphenyl
V        2,5,3' - trichlorobiphenyl           trichloromethoxybiphenyl
         3,3'   - dichlorobiphenyl            dichlorodimethoxybiphenyl
         3      - chlorobiphenyl
VI       2,6,2' - trichlorobiphenyl           trichloromethoxybiphenyl
         2,2'   - dichlorobiphenyl

Examination of the products formed, clearly indicates that ortho chlorines
yield products resulting from the loss of these.  In their absence, meta
chlorines were eliminated and para were the last to cleave.  The methanol
formed products by attacking at the leaving chlorine position.

Quantum yields of reactant disappearance were also determined for these
compounds.  These also showed a strong correlation with the position of
the chlorines.  Compounds I and III, which are non-ortho-substituted,
exhibited the  least efficiency for reaction.  This is believed to relate
to the preferred planar geometry for the excited triplet^   '; thus the
sterically hindering ortho chlorine leaves preferentially to relieve the
strain.

Ruzo  et al, also found the triplet to be the excited stateC   ).  In
cyclohexane, the efficiency of intramolecular energy transfer was 100%
(0  isc = 1.0   0,05] for compounds I, II and III,  The initial absorption
leads to an excited singlet which then quickly leads to the first trip-
let,

     1)   [A] + hv	>  [A]*
     2}  X[A]*	> 3[A]*

Since the quantum yields are the same for both ortho and non-ortho sub-
stituted compounds  the process is apparently not affected by planarity
of  the biphenyl,

                                    50
-------
 The intersystem crossing yield of 1.0  indicates  that  there  are  no  com-
 peting processes for the singlet,  i.e.,  fluorescence,  internal  conver-
 sion.   The resulting triplet  state is  believed to  be  the reactive  species
 leading to either deactivation,  dissociation, or direct reaction.  The
 lifetimes of the triplets also show a  correlation  with the  position of
 the substituent chlorines.  The  non-ortho  substituted compounds here
 demonstrate a lifetime 3 times longer  than the corresponding  ortho sub-
 stituted compounds;  but they  also demonstrate a  rate  about  10 times
 slower to react than the ortho substituted compounds  and a  deactivation
 rate constant 3 times slower  than the  ortho compounds.

 Ruzo et al.  proposed the following scheme  for the  reactions they observed.
 27)    Cl
28)
29)
30)    Cl
3D
32)
                                                                       Cl +HC1
                                                                          +C1
                                                                       Cl
                                     51
-------
Presumably the reaction of the biphenyl radical with oxygen would also
account for the observed phenolic compounds found by other investigators;
it should be noted,  however,  that if collision of the excited species
(the triplet) with oxygen occurs before dissociation of the oxygen an
excellent triplet quencher will lead to the deactivation of the triplet
to the ground state.

5.10.5  Ambient Measurements  -

A recent review of published  measurements of PCBs in surface waters found
PCBs quite ubiquitous.   A background level for unpolluted fresh waters
averaged about 0.5 ppt.f   J; the Great Lakes averaged about 5 ppt.
Moderately polluted rivers and bays yielded a common value of 50 ppt.,
e.g. the Milwaukee River.  Very polluted Japanese and U.S. rivers
averaged about 500 ppt.C153).

Few direct measurements of PCBs in air have been made.  EPA measured
between 1 to 50 nanograms/M^  in 4 major U.S. citiesQ^l) %  Another sur-
vey conducted by Woods Hole Oceanographic Institute found an exponential
decrease in concentration of PCBs with increasing distance from the
Boston-New Jersey industrial  complex(154)_  Concentrations ranged from a
high of 5 Ng/M-5 at Vineyard Sound to 0.05 Ng/M^ two thousand kilometers
out over the north Atlantic.   These values reflect the sum of vapor and
particulate samples and are uncorrected for collection efficiency.  Other
studies have indicated the presence of PCBs in air indirectly.  A study
of organochlorine pesticides  in rainwater in the British Isles found
PCBs present in all samples collected from 7 stations over a 12 month
period^   ).  Concentrations were not determined.  A similar study in
the south of Sweden noted PCBs present in aerial fallout ranging from
600 - 10,000 Ng/M3/month(156).

Extensive surveys of PCBs in fish and birds demonstrate a clear tendency
for accumulation and magnification in food chains.  The highest concen-
trations of PCBs are found in the fish eating and scavenging birds
(herons, terns, eagles) and in marine bird predators  (falcons).  The
highest concentrations in marine systems are found in the fat of the
top predators such as porpoises, sharks, and seals (6 - 1800 ppm).
Laboratory experiments have shown that aquatic invertebrates and fish
can accumulate 3 x 10^ and 7 x 10^ higher than ambient water; the top
predators may be as much as 10' higher than ambient water.  If fish-
eating birds are involved then magnification as high as 10^ or 10^ is
likelyC121).

Surveys of the occurrence of PCBs in man have been conducted by EPA.  Of
2189 samples analyzed PCBs were found at  1  - 2 ppm in 30% of the adipose
tissue samples(   ^,  Mean levels in human milk were of the order of 60
ppb; blood plasma averaged about 2 ppb,

Research into the toxicity of PCBs has been complicated by the variation
in composition from manufacturer to manufacturer and even from batch to

                                     52
-------
batch; in addition some commercial mixtures are known to contain toxic
contaminants such as p-chlorodioxins and chlorinated dibenzofurans(121).

Low level feeding of PCBs to rats demonstrates a tendency for accumulation
in the fat ^    ,  Once feeding has ceased as long as 240 days may be
required until the concentration in the fat reaches a peak.  A half-life
of 30 days has been observed in decreasing the concentration.  Hydroxy-
lated metabolites have been observed.  LDso for rats were of the order
of 5 - lOg/kg.  No deaths have ever been directly attributed to PCBs in
man.

Chronic intake of small daily doses of lOmg/kg over 50 days causes
chloracne in man^^M.  Reproductive effects have been observed in
chickens at 8 ppm continuous feeding and in fish at 0.9 ppb in ambient
water.

Release of PCBs to the environment from 1929 until 1970 has been largely
unregulated.  The American Conference of Governmental Industrial Hygien-
ists recommended a TLV of 1 mg/M^ and 0.5 mg/M^ for biphenyls of 42 and
54% chlorine content respectively^! )t

After 40 years of production Monsanto, under pressure from scientists
and government, voluntarily initiated a PCBs policy of sale only to
customers of closed system use.  This largely stopped sales for such
applications as paints, papers, plasticizers, sealants, and adhesives,
leaving only controlled use in electrical capacitors and transformers.
Spent capacitors and discarded transformer oils could be returned to
Monsanto for incineration.

On July 16, 1973 EPA and the FDA, in response to a report by CEQ and OST
recommending discontinuation of the use of PCBs in all but electrical
uses, announced policies concerning PCBs in industrial effluents and
tolerable limits in foods and its related packagingC158)<  EPA placed
PCBs on the toxic substances list as defined in the Federal Water Pol-
lution Control Act of 1972; it also announced it would limit discharge
of industrial wastes such that PCBs would not exceed 0.01 ppb in rivers
and lakes.  The FDA simultaneously announced a temporary tolerance
level of 2.5 ppm in milk and dairy products, 5 ppm in poultry, and 0.2
ppm in baby foods.  Also it banned the use of PCBs in plants manufac-
turing or storing animal feeds, foods, and food packaging.

PCBs have drawn sufficient concern to activate some international measures,

The World Health Organization in December 1972 announced it was studying
the health effects of PCBs and intends to issue environmental health
criteria(   ).  In February 1973 the Organization for Economic Cooper-
ation and Development representing Japan, Australia and the industrial
nations of Western Europe and North America adopted a directive calling
upon its members to limit the use of PCBs to transformers, capacitors,
heat transfer fluids  (in other than food, drug, and feed operations),

                                     53
-------
and hydraulic fluids for mining equipment; they also called for control
of the manufacture, import, and export of product containing PCBs'   '.

5.11 Review of G.C. Analytical Procedures for Halocarbons

The literature that exists for gas chromatographic halocarbon analysis
deals primarily with separations at relatively high concentrations
characteristic of quality control production requirements.  Reed^   J
evaluated the resolving power of a number of stationary liquid phases
for fluorocarbons and reported the ethyl ester of Kel-F acid 8114 to be
the most effective,  Dresdner et al.(l62) used the same packing to
analyze 6- and 12- carbon fluorocarbon derivatives of SFg.  Ellis et al.
(163) us«d a packing of Kel-F oil on Fluon powder to separate reactive
inorganic compounds such as GIF, HF, Cl2, C1F3, UF6 and Br2-  Mixtures
of nitrogen trifluoride with CF4 were investigated by Nachbaur and
Engelbecht (.164) using moist silica gel with hydrogen as carrier gas
at 0°C.  Campbell and Gudzinowicz (1°5) used diisodecyl phthalate and
Kel-F No. 3 oil on Chromosorb W with 1/4 inch columns of varying
lengths to measure several fluorocarbons and sulfur fluoride compounds.
demons and Altshuller(l66) determined the relative responses of an
EC detector to a number of halocarbons and sulfur halides using a Baymal
or an SF 96 column for separation.  Greene and Wachi(167) used CH2=CHC02
(CF2-CF2)3H coated on Chromosorb W for the separation of several low
molecular weight fluorocarbons and Lysyj and Newton (168) found several
packing of halogenated polymers plasticized with halogenated oils useful
for the separation of some halocarbons.  Williams and Umstead(169) used
Porapak Q and S in an on-line column concentrating device with temperature
programming to separate several halocarbons.  Low concentration mixtures
(10 to 20 ppb) were concentrated to ppm levels (1 to 2 ppm) and then
measured by GC using a microcoulometric detector.  This detector was pre-
ferred to the electron capture  (EC) detector because of the latter 's
narrow linear range, lack of sensitivity to some compounds, and extreme
sensitivity to others.
Priestley et al.      developed a GC method for phosgene using an EC
detector.  An aluminum column packed with didecyl phthalate on GC 22
Super Support provided good separation.  Jeltes et al.(-^l) used a similar
packing  (diisodecyl phthalate) to determine phosgene and dichloroacetylene
in air at their subthreshold limit values.

Analytical methods for SF6 and a limited number of halocarbons have been
developed for meteorological tracer studies(20,172,173,174) _  Lovelock
(175) measured background concentration of ambient CClsF, CC14 and CHgl
over the North and South Atlantic using a silicone stationary phase and
a novel  coulometric system.  Hester et al.(176) used a stainless steel
column containing Na2S04 on Porosil A and temperature programming to
measure  CCl^F and CC12F2 i-n L°s Angeles.  The presence of atmospheric
CC14, trichloroethylene and tetrachloroethylene was reported.  However,
based on the chromatogram presented, better resolution of components
would be necessary for accurate analysis.

                                     54
-------
                                 SECTION IV

                                EXPERIMENTAL

4.1  Reactors

4.1.1  Teflon bags and Myler bags -

4 ft. x 4 ft., five mil FEP Teflon bags were manufactured in the laboratory.
Teflon film in roll form from DuPont was folded over and heat bonded on
three edges with a 1/4" wide thermal-impulse heat sealer from Vertrod,
Inc. of Brooklyn, N.Y.  Some compounds (C114, 111T, F-ll, F-12, F113)
were found to permeate through Teflon.  In these cases identical bags
of Myler were manufactured and used.  These compounds did not permeate
through Myler.  The volume of the bags when filled was 200 liters (Teflon)
or 144 liters (Myler).  Both bags were equipped with two ground-glass
ports for filling and sampling, and both were transparent to the wave-
lengths of the incident light.  Irradiations were performed by exposing
the aluminized Myler-backed Teflon bags to a bank of 24 48" rapid start
40-watt fluorescent lamps.  Mounted side by side the lamps formed a wall
52" x 52".  The bank was enclosed by 4 walls (extending 22" outward),
which along with the reflectors of the lamp fixtures were covered with
reflective aluminized Myler.  Thus the side opposite the light bank was
open in order to accomodate the Teflon bag.  Four small electric fans were
mounted in the walls in order to ventilate excessive heat generated by
the lamps.

The use of 3 different types of fluorescent lamps permitted the approximation
of the quality and quantity of middle and near ultraviolet radiation found
in the lower troposphere.  Twelve G.E. F40 BLB, 6 G.E. F40 BL and 6
Westinghouse FS40 fluorescent sunlamps were evenly distributed across tLe
24 mounts.  The F40 BLB and F40 BL lamps emit most of the UV energy around
360 nanometers.  The middle ultraviolet was supplied by the FS40 sunlamps
which emit their peak energy around 310 nanometers.  Kj for Teflon bag
irradiations was 0.39 min.~ , and for Myler bags was 0.28 min.'l, due to
the lower transmission of Myler.  Figure 5 shows the comparative spectral
distributions for this array and tropospheric radiation.

4.1.2  Pyrex Reactor -

A 72-liter Pyrex reactor was used in some experiments when long irradiation
times were desired.  It was manufactured by Ace Glass of Vineland, N.J. and
was equipped with a thermometer, as well as 3 ports for sampling, filling
and venting.  An all-glass, magnetic stirrer was enclosed in the sphere to
promote mixing.  The reactor was used in an air conditioned irradiation
chamber equipped with 24 Westinghouse black light bulbs provided by the
Environmental Protection Agency.  KI was 0.3 rain.  .

4.1.3  Quartz Reactor -

A one-liter Hanovia photochemical reactor was used for studies in the U.V.

                                      55
-------
                              TUFE 5
     cO:'?A?;::r.r
VS.
                                    PADIATIC.J.
 00
 p:
 w
 E-:
 B
 c
 ^
 o
 CO
M^
 O

 g
 CO
 a

                                        ;CI.  (11,22)
                                        i::  ?£7£?Z:iCE  (37)
     r-:io
          280
300        320        3^0

        WAVELENGTH
                                    360
380
                                    56
-------
The reactor had a 450 watt high pressure mercury vapor lamp (>2200A).

4.1.4  Light Intensity Measurements -

The photolysis of nitrogen dioxide in air was used to measure the light
intensity generated by the lamp array used in bag irradiations, and also
for the array used with the 72 liter reactor.  This measurement was made
at 30°C at zero relative humidity and was performed before, after, and
in the middle of all the experimental runs.

A 50 pphm concentration of nitrogen dioxide was produced in the bags
utilizing the nitrogen dioxide permeation tubes (see Section 4.3).  After
ten minutes of irradiation, the steady-state concentrations of nitric
oxide, nitrogen dioxide and ozone were measured.  With Kj as the reaction
rate for the reaction

          N02 + hv     kl	   NO + 0
                                   >
          in excess oxygen,
          K  = (25.5 ppnT1 min"1) [NO][0$]
           1          [N02]
NO, 0, and N02 concentrations were measured at steady state, and Kj
calculated.

4.2  Preparation of Samples for Irradiation

4.2.1  Materials -

All chemicals were analytical reagent grade, or otherwise the best available.

Ultra-zero air manufactured by Matheson Gas Products of East Rutherford,
N.J. was used in all experiments except those in nitrogen.  The air was
further purified by successive passage through an activated charcoal trap,
Ascarite, and molecular sieve.  The air so treated had no detectable
halocarbon contaminants with the exception of CCljF which was present in
concentrations of less than lO'^v/v.  Analysis showed less than 0.1 ppm
total hydrocarbon (expressed as Cffy) and less than 10 ppb NOX.  Pre-
purified nitrogen was manufactured by Matheson Gas Products and was further
purified by passing it through traps containing activated charcoal, anhydrous
calcium sulfate and Ascarite.

The hydrocarbon fuel used in the photochemical experiments was a mixture
of paraffin, olefin and aromatic hydrocarbons.  It was designated "Fuel A"
and was obtained from Exxon Research, Inc.

Its composition was 59.74% paraffin, 13.26% olefin, and 20.98% aromatic
hydrocarbons.  Detergents and additives, mostly long-chain amino com-
pounds made up the remainder.  This fuel mixture was used as a source of
free radicals in the simulations.  Sufficient hydrocarbon was introduced
to the chamber, using a 10 microliter syringe to achieve 1 ppm.

                                     57
-------
NC>2 was obtained from permeation tubes manufactured by Analytical Indus-
trial Development Co., West Chester, Pa.   Allowing one week to obtain
thermal equilibrium the tubes were weighed on a Sartorius Analytical
Micro-balance and the weight plotted against time.  The average leak-
rate for nitrogen dioxide tubes was 30,000 nanograms/minute.

4.2.2  Humidity -

50% relative humidity was used in all experiments.  It was achieved by
injecting the calculated volume of distilled water into the filling gas
stream.

4.2.3  Temperature -

A tele-thermometer manufactured by Yellow Springs Instrument Company was
used to measure the bag chamber temperature.  A probe was inserted into
the bag through one of the glass ports.  A maximum temperature of 35°C
was reached after one hour of irradiation and the temperature remained
relatively constant thereafter.

4.2.4  Chamber Filling Procedure -

The Teflon or Myler bags were connected via a ground glass port to the
tank of ultra-zero air or N2 with its train of purifying traps already
described.  A rotameter  (Ace Glass #4-15-2) served to monitor the flow-
rate which was generally about 5 liters rnin."^.  The test substrate, if
a liquid, was added to the inner surface of the port, so that the diluent
gas passed over it to allow evaporation into the bag.

In other cases, double dilution was used to achieve the desired concen-
trations, or permeation tubes were used.  Double dilution involved
injecting a measured quantity of the substrate into a clean four-liter
flask  through a. rubber septum.  The flask had two stainless steel balls
to facilitate mixing.  After allowing five minutes for evaporation and
diffusion a 5 cc aliquot was extracted and injected directly into the
bag chamber.  Permeation tubes are described in Section 4.3.

Nitrogen dioxide was then added by attaching a Teflon line  from the per-
meation apparatus to the bag.  The time required  for the desired NC>2
concentration to be achieved in the bag (50 pphm) was determined by
calculation from the known lead-rate of the permeation tube.

The bag was then mixed by slapping the sides of the bag 30  times.  The
experiments conducted in bags employed no stirring except this initial
mixing of the chamber contents before irradiation.  The initial concen-
trations of ozone, nitrogen oxides, nitric oxide, temperature and the
concentration of the  substrate were determined  (see Section 4.4).  The
chamber was then placed  in front of the light  source.  Before the
irradiation was started, the  lamp array was turned on for approximately
30 minutes to allow the  lamps to attain constant  temperature and thus
constant output.  Aluminized Myler was attached at the back of the bag

                                      58
-------
chamber for use as a reflector.  Measurements of substrate and product
concentrations were then made at 15 minutes, 30 minutes, 60 minutes and
at approximately one hour intervals thereafter.  In the case of reactive
substrates irradiations usually lasted until a decay of one order of
magnitude was observed.  For very long irradiations the nitrogen dioxide
was replenished daily to 50 pphm.

The 72 liter reactor, being a rigid chamber, required special filling
techniques.  Cleaning was achieved by flushing 10 times the volume of
air through the reactor.  Double dilution of substrate was employed.
After injection, the stirrer was switched on for 5 minutes.  Nitrogen
dioxide replenishment was achieved by a 200 cc injection of a concen-
trated nitrogen dioxide mixture derived from a low flow off the per-
meation tubes into a 1 liter flask.  The concentration of 50 pphm was
obtained empirically as the small size and rigid nature of the chamber
precluded sampling during a run.

Sampling was accomplished by attaching a Teflon line from the appropriate
instrument to the bag utilizing ground-glass ball joints for connections
and a stopcock to prevent back flow.  Gas chromatograph samples were
withdrawn through a rubber septum placed in one port by an all glass
syringe and immediately injected into the gas chromatograph.

The bags were flushed twice with ultra pure air between each run.  Each
experiment was duplicated.

4.3  Permeation Tubes
Permeation tubes were calibrated and used to provide known concentrations
of several of the compounds studied (F-ll, CC14, PCE, TCE, CH3I, F113 and
vinyl chloride) and of N02 and phosgene.  The permeation tubes were main-
tained at 30.0 ± 0.1°C in a water-jacketed mixing chamber except where
noted in Table 4.  Constant leak rates were usually established within 1
to 2 weeks of conditioning, as indicated by constancy in the rate of
weight loss when diluent air at 50 ml. min.~l was passed over them.
Table 4 shows the weight loss of the permeation tubes for CH3I, CC14,
CC12F2, CC13F, CH2C1F, CH3C1, CH2C1CH2C1, CC12, FCC1F2, CC12CHC1,
CH2CHC1, COC12.  Tubes were weighed on an average about 3 times per week
using a semi-micro balance.

4.4  Laboratory Analyses

4.4.1  Gas Chromatograph -

The concentrations of the halocarbons were measured by direct injection
into a gas chromatograph.  Two GC units were used in this study which are
referred to as systems A and B.  System A was a temperature programmable
Fisher-Victoreen 4400 series GC and was equipped with a 15 mCi °^Ni EC
detector.  Full scale deflection (FSD) on a 1 mv recorder was 10~1^A.  It
was operated in the pulse mode (500 ysecs).  Prepurified nitrogen was
used as a carrier gas.  A flame ionization detector was used for vinyl

                                      59
-------
 (C
-P
 0)
•g
 C
 O
•r-l
-P
 to
 0)
            n   >
            O   (U
            M  P
            (-1
            w    •

            ^  w
                  I
                    c
                   •H
 c
 o
•H
4-1
 rO  4J,_r
 cp  rd  i
 6  OH  g

 «      ^
 0,
 E  O
 (DO
 E-"
                          CM
                                  in
                              H  in
                              T>  CT> O
                               •   •   •
                                                 oo CN
                                                                           ro
OOOOOOOfOOOOOOO

ooomooocrioooooo
^*
cu
/->
rM
EH
en — s
en en
rH CU 0)
rH d rC
rt) X U
-H -H
r? —
oooLnocMincMocNoooo
OOOrHOOr-IOOOOOOO
oooooooooooooo
                                                                                              fO
                                                                                              
                                                                                              M
                                                                                              0)
                                                                                              CO
                                                                                              ,Q
                                                                                              O
                                                                                                  (U
 e
•H
 CO
 CO
 O  4J
rH  0)
    
 (U  r-l
•H  3
 S  m
    0)
 i
rQ  rt>
    T!
 en
^  o
-P  rH


 I    .
    Vi
 O  (0
 5  (U
EH  C
    •H
                                                                                               (U   to
                                                                                              rQ   IQ
                                                                                               3   O
                                                                                              -P  rH

                                                                                              4-1  4J
           'C —
             •  03
           •rl  QJ


            0)  U
•C
 C
 3


 I
 O
OOOVOOvOvOvOOVOOOOO

rHrHrHrHrHrHrHi-lrHiHrHrHrHrH

oooooooooooooo
                              rH  rH   CM  CM
                              rj  tj  fa  fa
                      *       CM CMrH  H rH
           *         *      WWUCJU'-H
     CM     CM       fa     uuyoffiu
    rH     fafafarHr-lrHrHfa   CM O  K
H  u   "* CM  n ntj  O U  U   f^fa   f^O
 CO  CMrH rH  rH  rH   CM  n CM CMrH  rH rH   CM

UUOOUCJUOUOUOUO
                                                                                   c  oi
                                                                                   •H  $
                                                                                   (U
                                                                                   S
                                                                                   to

                                                                                   0)

                                                                                   •H
                                                                                       Q)
                                                                                                   (U
                                                                                                   CO
                                                                                               to   >i
                                                                                               CO   (T3
                                                                                               
-------
chloride with helium as the carrier gas.  System B was an isothermal unit
equipped with two identical 15 mCi   Ni EC detectors in series.  The
electrometer of each detector was connected to one channel of a Soltec
dual pen recorder.  At maximum sensitivity FSD on a 1 mv scale was
3 x 10~^^A.  The instrument was operated in a pulse mode (400 ysecs) .
The operating characteristics of this special purpose instrument have
been described in
Since water vapor would mask important peaks, a 2 in. x 14 in. o.d.
Teflon tube filled with Ascarite was routinely inserted (except for
phosgene analysis) between the EC detector and all columns used.  For
Porapak Q above 80°C, the Ascarite was not very effective; however,
resolution was adequate.  The Ascarite was replaced when the water peak
began to appear.  All -glass syringes were used since Teflon gas-tight
syringes exhibited a continuous bleed of unknown interfering compounds.

4.4.2  Nitrogen Oxides -

Nitrogen oxides (N + N02) , nitric oxide and ozone were measured with an
Aerochem Model AA - III Chemiluminescence Monitor.  The instrument is
based on the chemiluminescent reaction of nitric oxide with ozone.  The
analysis for ozone required a constant source of pure nitric oxide where-
as the constant source of ozone for nitric oxide analysis was only dried
room air passed through an enclosed ozonator.  The analyzer was specific
for ozone and nitric oxide; nitrogen dioxide was reduced to nitric oxide
in the instrument by passing the sample stream over a heated catalyst and
read as total nitrogen oxides.  The monitor sampled at 2.4 liters per
minute with a 95% response time in 30 seconds.

Calibration was achieved by feeding a known concentration of nitrogen
dioxide in air from the permeation tubes and adjusting the potentiomete-
until the read-out galvanometer was correct.  Nitric oxide was automatically
calibrated as well due to the 99% efficiency of the catalyst.  The Ozone
mode was calibrated by performing an internal gas phase titration described
in the instrument manual.  Double checking was done periodically using
both span gases of nitric oxide in nitrogen manufactured by MG Scientific
of Kearny, N.J. and the standard Saltzman method^   ^ for nitrogen dioxide.

4.4.3  Ozone -
Ozone was measured with a Rem Chemiluminescent Ozone Monitor.  This monitor
is based on the chemiluminescent reaction of ozone with ethylene gas.  The
reaction produces an excited species whose light signal produced in the
photomultiplier is proportional to the ozone concentration.  The sampling
flow-rate was one liter per minute.  The monitor was calibrated by setting
the gain control to equal a concentration measured by the neutral buffered
potassium iodide standard method.  A Rem Ozone Generator was used to
generate a steady-state concentration of ozone for calibration and for
ozone dark reaction studies.

                                     61
-------
4.4.4  Light Scattering Aerosol -

This was determined using an MRI integrating nephelometer.   Particles of
radii between about 0.1 and 10 microns are measured in terms of their
scattering coefficient 8 scat.  This is empirically related to the mass
loading after subtracting the molecular scattering contribution.

4.4.5  Phenols -

Phenols were collected by absorbing them into sodium bicarbonate solution
and analyzing by the colorimetric procedure described by Braverman et al.
(   ).   The analysis was based on the reaction of diazotized p-aminodi-
methylaniline sulfate with phenolic compounds to form a dye which can be
determined colorimetrically.  With the collection of a 10:l gas sample and
the use of 40 mm spectrophotometer absorption cells a sensitivity of about
0.1 ppb was realized.

4.4.6  Aldehydes -

Aldehydes were determined by the sulfoxylate method(179)f  xhe method is
sensitive to aldehydes which will combine with sodium bisulfite to form a
non-volatile addition product.  The bisulfite is later released and
determined to quantitate the aldehydes present.

4.4.7  Phosgene -

Phosgene was analyzed with the Fisher Victoreen gas chromatograph.  Sepa-
ration was achieved using 3 ft. of 1/4" o.d. aluminum packed with 30%
didecylphthalate on 100/120 mesh acid washed chromosorb P.   A flow of
40 cc/minute nitrogen was maintained through the column along with 90 cc/
min of argon/methane (90/10) purge gas through the detector.  The oven
temperature was operated at 30°C and the detector at 200°C.  The detector
was operated in the pulse mode at 500 microseconds.  The detector was
calibrated according to the pulse-flow coulometry method developed by us
and described in detail in Section 5.3.  With a 10 cc sample the method
had a sensitivity of about 0.1 ppb.  A calibration curve is shown in
Figure 6; standard phosgene concentrations were obtained using a per-
meation tube.

4.4.8  Chloride and Hydrogen  Ion -

A sampling train consisting of a 5 mm i.d. teflon tube with an 18/7
socket joint, midget impingers, trap, rotameter, and vacuum pump was used
to collect HC1 from the bag samples.  The gas was drawn through the im-
pingers which were each charged with 5 ml of distilled water, at the rate
of 1 liter min."  for 10 minutes.

Chloride analysis was performed potentiometrically.  A Corning Model 12
Research pH meter equipped with a Coleman 3-802 Ion Selective Electrode
and a Corning Double Junction Ceramic Reference Electrode was calibrated

                                     62
-------
                          FIGURE 6



     GAS CKROMATOGRAPHIC ELECTRON CAPTURE  CALIBRATION



                     CURVE FOR PHOSGENE.
   100
to
  10
o
P-
CQ
§
  1.0	

    0.01
         -J	l_
0.1
                PP'A PHOS^E-VE X SA'-'PLE SIZE (MILLILITEHS)
1.0
                               63
-------
against standard Cl  solutions at 25 C and were used to measure the Cl"
concentration in impinger samples.  The EMF measured was compared against
the calibration curve of log (Cl~) vs EMF and the concentration obtained
(see Figure 7).  The concentration of Cl" in the sampled gas was cal-
culated by the equation:

          Concentration Cl" CV/V, ppm) = L X VL . 24.4 liters . ,n6
                                          V          mole
where  L = choride ion concentration in the liquid analyzed moles/liter
      VL = 1Q~2 liter = volume of collection water
      Vp. = 10 liters = volume of air sampled
       o

After the chloride analysis was completed the pH of the same samples were
determined.  The same pH meter was employed with a Corning Combination pH
Electrode.  The electrode was standardized against a phosphate buffer.  A
similar calculation was performed in order to obtain the H+ concentration
in the air sampled:

          H+ cone in ppm = [H+] x Vj  .  24.4 1  . 1Q6
                              Vg           mole

4.5  Field Analysis - Mobile Laboratory

A Winnebago motor home equipped with the required aerometric monitoring
instruments was used for on-site field studies initiated after May 1974.

The gas chromatograph equipped with a 10 mCi °^Ni EC detector and a flame
ionization detector (system A) was used for halocarbon analysis.  The
other instruments used in this study were the Aerochem NO-NOx-Oj analyzer,
the REM ozone analyzer and the MRI integrating nephelometer.

Prior to May 1974, grab samples from various locations were analyzed in
the New Brunswick, N.J. laboratory.  One hundred-mi all-glass syringes
each fitted with a three-way Luer-Lok valve and a septum were found most
convenient for this program and exhibited less than 10% halocarbon loss
over a 48 hour period.  All-glass syringes were used for GC injections.
An all-glass manifold was used for ambient sampling of nitric oxides and
ozone.
                                        64
-------
                            FIGURE 7

      TYPICAL  CHLORIDE ION ELECTRODE CALIBRATION CURVE.
PC
o
M

M

S
C?
    10"
    10
      -2
    10
    10
    1C
      -5
    10"
                        160
                                    180
200
220
                  CKLO°IDS ION ELECT^OIE POTENTIAL
              VS.  DOUBLE JIIJCTIOH PE^EREljCE ELSCT?0?E
                            (MIILIVOLTS)
                               65
-------
                                 SECTION V

      GAS CHROMATOGRAPHIC ANALYTICAL PROCEDURES FOR TRACE LEVELS OF

                            HALOCARBONS AND SF6

5.1  Column Evaluation

The nine columns used in this study are given in Table 5 and are referred
to by their designated numbers.  Unless otherwise indicated, data presented
here were obtained with System A.  The optimal isothermal temperatures
for the separation of sub-ppb mixtures with air of SF^, CBrF?, CHC12F,
CC12F2, CC13F, CH3I, CC12F-CC1F2, CHC13, CH3-CC13, CC14, C2HC13, C2C14,
COC12 and CH2=CHC1 using the indicated columns, are given in Table 5.
For mixtures, optimal temperatures were chosen for adequate resolution
combined with minimum total elution time.  For single compounds, this
elution time was limited to less than 10 minutes.  Ppm concentrations of
CH3I, CCl2,F-CClF2, CHC13, CH3-CC13, CC14, C2HC1_ and C2C14 were generally
required for detection using column 1.  The useful chromatograms of
ambient injections and synthetic ppb injections of SF6 and CBrF3 are
given in Figure 8.  Figure 8 (C) also demonstrates the effect of purge gas
on the EC response to a 19 ppb mixture of CC12F2.  Figures 9 and 10 are
chromatograms of ambient air samples using Chromosil 310 (column 2) and
Carbowax 1500 (column 3), respectively, where the latter includes a
chromatogram of a ppb synthetic mixture of CH2=CHC1 using a flame
ionization detector (Figure 10B).  The chromatograms of typical ambient
air samples using columns 5, 6 and 7 are shown in Figures 11, 12 and 13,
respectively, and the dual trace coulometric chromatogram obtained with
System B using a DC 200 packing  (column 8) is given in Figure 14.  For a
typically polluted day in Bayonne, N.J., ambient concentrations cal-
culated from peak  height versus concentration calibration plots are
compared with corresponding coulometrically calculated  (equation 3,
Section 5.2.1) concentrations in Table 6.  The chromatogram obtained
with column 9 (System B) of a 0.4 ml injection of an irradiated simulated
tropospheric photochemical reaction mixture of 1 ppm C2Cl4 and 50 pphm
N02 (50% RH) demonstrating phosgene synthesis is shown in Figure 5.

At relatively high concentrations  (10  to 10* times ambient) the compounds
of Table 5 exhibited good separation on Porapak Q (column 1) at the
indicated temperatures, suggesting its applicability for ambient halocarbon
analysis.  Using the Fisher Victoreen GC  (System A), chromatographs of
ambient air samples (New Brunswick, N.J.) at each of the determined
optimum temperatures, however, revealed that only CC12F2 and CC13F could
be measured with this column (Figures 8A and 8B).  Figure 8 also demon-
strates, using CC12F2 as an example, a phenomenon common to all halocarbons
under study: the use of purge gas  (10% methane/argon) reduced the sensi-
tivity of the EC detector to these compounds.  This effect of purge gas is
attributed to a decrease in ionization efficiency with  increasing flow rate
as predicted from equation 1, Section 5.2.1.  The use of purge gas accordingly
would only seem to be indicated  at relatively high solute concentrations.

                                      66
-------
Temperatures for Ambient Halocarbon Analysis
•o
ro
CQ
5
3
H
O
U
r-*
3
MJ
00
co
£3


•
in

CO

rd
EH


O CJ
0 0
o m
CO VD
i-H
fa -
CM ro
rH rH
U U
gg
0 0
MH MH
U CJ
0 0
O 0
rH «
ro - rH
fa CNU
k fa CM
« rH CJ
CJ O
O k
•O 1 O
C fa MH
ro CM
H O
VOCJO
fa CJ 0
CO O
k CM
k 0
0 MH T3
(11 f*
cj ro
uo
0 m ro
O ro rH
ro H CJ
33
• • CM
H U
CO
Sk
0
MH
°"i«
,* roo
ro o
Qi fa CO

en
4-1
c
Q)


0
CJ
ro
k
o
&4
43
en
CO
g

roH
rH
CJ -
O ^r
rH
k CJ
o o
MH
J»^
CJ O
OO MH
43
4-1
•H
^

tn
C
O
•rH
4-1
ro
u
•H
•H
U
CO
ft

0
r-H
X^
0
CD

••»
5
co

rH

^

VD

CO
CO
o
ro CJ
•HO

- r-
CNH
fa
CM -
rH ro
U rH
CJ U
CJ
k ro
0 K
MH CJ




rH
fa
ro
H
CJ
U
CM
fa
CM
H
8
O
CJ
O
CO
o
rH
ro
•H
en
0
J_l
g
43
en
CO
g

o
o
H
O
CO

• h
-
00
^s^
rH

^

CM
rH

CO
co
H
CJ
CJ
CM
fa
CN
rH
U
CJ
k
o
MH
CJ
0
ro
CM
•a
1
k
ro
CJ
43
en
CO
o
o
H
o
CO
o
o
0
m
rH
ro
o

^J
fd
U
<&
^y
»
o

(«.
»
co

rH

^

CT^

co
co













*
H
CJ
S3
O
II
CM
g




xyl sebacate on 30/60 mesh acid washed (A/W) Chromosorb W
CO
43
rH
43
4J
CO

CM

•H

r)P
O
CM

•«<
-
CO

rH

^

[">»

CO
co
0
MH
O
0
CO
CM
fa
ro
H
CJ
CJ
0
MH
CJ
O
CTi
H
•a
0
w
0
g
CO H
CO CJ
g JS
o
o -



fa
ro
rH
CJ
CJ

0
MH

CJ
3
O
in

•

k
t




rH
O
CO
fi
0

o
.
H
ro
33
CJ




H
ro
33
CJ
fa
ro
H
CJ
U
O
MH
CJ
0
ro
CM
• CM
rH
Scf
•Su01
0
en >
O ro
SrH
CJ
k 33
43 CM
U U
en ^
CO rH
EB
o
VD »
\ ro
O
ro
C
O
O
o
CM

CJ
Q
*
0
rH

• h
;
^Ji
s-ss
rH

^

m

to
co
rH
8
ro
g

^
ro
rH
U
g

^
CM
fa
H
CJ
CJ

fa
CM
H
CJ
CJ




yl phthalate on 100/120 mesh Chromosorb P . . . 23 C for
u
CO
•c
•H
Q
dP
0
ro

*•>. •
= CM


CJ
X
•o
= 5
co ro
rH
~ fa
6 ro
3 H
G CJ
•H CJ

3
H
r
-------
                           Figure 8
Ul
                            CC*
                         COLUMN I, 130° C
                         CARRIER (N2)FLQWRATE = 60mfi/MIN
                         AMBIENT INJECTION SIZE = 10.0mfl
                            FSD 8XIO~11  A
                                                      B
                             COLUMN I , 80° C
                             CARRIERIN2) FLOWRATE = 40mJ2/MIN
                             AMBIENT INJECTION SIZE = 5.0m fl
                                FSD 8XIO~" A
                                  CCA 2F2
                                      0.28 PPB
                                         I	I
PURGE GAS FLOW RATE
 O.Om£/MIN
                90m£/MlN
           J	I
COLUMN I  , 80° C
CARRIER (N2)FLOW RATE=40mC/MIN
PURGE GAS 10% CH4/Ar
SAMPLE SIZE  1.0 mS.
 FSD 1.6 X IO~'OA
   ppb CCS. 2 F2 MIXTURE
          I   I    I    I    I
                             COLUMN I , 30°C
         FSDL6XIO'IOA
                0.5 PPB
                 CARRIER (N2) FLOW RATE = 40mfi/MIN
                 SAMPLE SIZE I.Om.2
                                              FSD8XIO"nA
                                                 12.4 PPB
                            T
                         T
                            CBrF3
                            6       8
                              MINUTES
                                 10
                  12
14
                                    68
-------
                      Figure 9
6
CO
UJ
X
o
? 4
K
X
o
UJ
X
2
—

—


—


_

-











C
C







FSD I.6XIO"'°A
vC'T
8
CO
Ul

o

I
I-
X

UJ
X
                        COLUMN 2 , 23° C

                        CARRIER (N 2 ) FLOW RATE=20mfi/MIN

                        AMBIENT INJECTION SIZE = 0.5mje
                        COLUMN 2 , 23° C
                        CARRIER (N2)FLOWRATE = 30mtf/MIN

                        AMBIENT INJECTION SIZE = 4.(

                          FSD 1.6 X 1C
                                  CC23F,0.8ppb
                                                      ,0.25ppb
                       L
                             I
I
I
I    I    I     I
                                     8    19   20
                                                    22
                        MINUTES



                               69
-------
                          Figure 10
  8
CO
Ui
I
          H20
                            COLUMN 3,23°C

                            CARRIER GAS(N2) FLOW RATE = 20mfi/MIN

                            AMBIENT INJECTION SIZE= 5.0 m£

                              FSD 8XIO""A
   6

MINUTES
                                    8  10
                                                 B
       COLUMN 3, 23° C

       CARRIER (He ) FLOW RATE = 20mfi/MIN

       SAMPLE SIZE  10.0 mi

       FLAME IONIZATION DETECTOR
                                              14
I 4
i-
x
o
LJ
X
              CH2=CHCC

                  FSD8XIO"I3A

                  22.1 PPB
      K FS
,      l\  2

   -^^
            24

           MINUTES
                                70
-------
                    Figure 11
8
                CCS. 3F
                   0.14 PPB
                        COLUMN 5,-l9°C
                       (LIQUID N2 USED FOR CRYOGENIC OPER.)
                        CARRIER (N2) FLOW RATE = 25mf/MIN
                        AMBIENT INJECTION SIZE = 4.0 m8.
                        FSD 8XIO"MA
          2       4
          MINUTES
Se-


6
UJ
i
o
z
i 4
•
r—
o
UJ
I
2



•

-


-




•J
COLUMN 5 , 23° C
CARRIER { N2) FLOW RATE = 40mJ?/ MIN
AMBIENT SAMPLE 6.0 mi?
FSD 8XIO~" A




CH3-CCJ23,O.I5ppb
/

^CC^Alppb Q2ppb
1 1 1 1 1 1
0 4 8 12
MINUTES
                            71
-------
CD
^
                 S3HONI-1H9I3H
                        72
-------
E

8
it
<
(T
                -
                 t
                 q
                 in
            10
-------
The identity of both CC"L^2 anc* CC1,F was confirmed early in our experi-
ments by retention data on Chromosil 310 and Carbowax 1500 (Figures 9 and
10).  These columns also resolved 0014.  Reference to a chromatogram
obtained on a similar air sample using DC 200 and System B (Figure 14)
clearly illustrates that CH3I, CC12F-CC1F2, CHC13, CH3CC13, CC14, C2HC13
and C2Cl4 suffered irreversible losses on the Porapak Q column.  Since
synthetic mixtures of SF^ and CBrF3 could be easily detected above 0.001
ppb and 0.005 ppb respectively, we must conclude that background SF^ and
CBrF3 are present at levels below these values.   This is supported, in
part, by Lovelock^ ) who reported background SF6 concentrations of 1.2 x
10~1* v/v.  Based on production figures CHC12F is probably present below
10~12 V/Y also.  This is substantially below the EC sensitivity for this
compound (15 ppb) ; however, because of its inertness CHC12F should not
suffer significant losses on Porapak Q.  It should be noted, however,
that SF^ and CBrF3, by virtue of their low background concentrations,
inertness, excellent electron absorbing properties, and good resolution
on Porapak Q at ambient temperatures (Figure 8D) , can serve as good
tracers for dual source studies.

The recent evidence indicating industrial exposure of workers to vinyl
chloride as a possible cause of a rare form of liver cancer known as
angiosarcoma supported the inclusion of vinyl chloride measurements in
our ambient monitoring program.  Since the flame ionization detector was
found to exhibit a greater sensitivity to vinyl chloride than did the EC
detector, GC conditions were optimized with the former.  A sensitivity of
10 ppb was achieved.  No detectable vinyl chloride was measured at Sea
Girt, N.J.; New Brunswick, N.J.; Sandy Hook, N.J. or New York City (45th
Street and Lexington Avenue) during short term monitoring efforts in
June 1974.  In our current monitoring efforts vinyl chloride concen-
trations as high as 1500 ppb have been measured in Delaware City, Delaware
(intersection of State Road 448 and Route 72) .
Based on the excellent separation of air and CC1F2-CF3, CH3-CHF2,
CC12F-CC1F2, CHC1F2, CC13F and CHC12F at high concentrations on a di-2-
ethylhexyl sebacate packingC-^"^) this packing was evaluated for ambient
analysis at various temperatures for the compounds under study.  Only
CC13F could be detected, indicating significant sorption of the other
compounds by this column.  An SE 30 packing on the other hand, was quite
useful.  With this packing, it was possible to separate, identify and
quantify CH3CC13, CC14 and C2Cl4 in the ambient air at room temperature
(Figure 11) .  Additionally, CC13F could be properly separated from the
air peak by cryogenic operation at -19°C (Figure 11) .

DC 710  (column 6) facilitated the detection of an unknown ambient com-
pound  which subsequently was confirmed as CH3I (Figure 12) .  Additionally,
this column provided excellent resolution of CC13F.

In an ancillary  study to determine ambient concentrations of peroxyacetyl
nitrate (PAN), Carbowax 400 was found to resolve ambient CC13F, CC14 and
C2Cl4  (Figure 13) .  This finding was fortuitous because it allowed
additional confirmation of the compounds identified on the SE 30 column

                                      74
-------
by virtue of the significantly different characteristics of the two
columns.  The unknown peak on the chromatogram remains to be identified.

By far the most useful packing for ambient halocarbon analysis was DC 200
(column 8).   With this column, excellent resolution was obtained for
CC13F, CH3I, CC12F-CC1F2, CHC13, CH3-CC13, CC14, C2HC13 and C2C14 (Figure
14).   Additionally, the separations were achieved isothermally at room
temperature.  Confirmation of compound identity was obtained by use of
the previously presented retention data and the novel application of
ionization efficiencies.  In this, the calculated ionization efficiency
(equation 2, Section 5.2.1) of a compound, tentatively identified by
retention data, was compared with that of a standard mixture for equality.

The relatively close agreement between the calibrated and coulometrically
determined concentrations for CC13F, CH3I and CC14 (Table 6), and our
experience with coulometric errors as a function of ionization efficiencies,
indicate minimal sorption errors for the DC 200 column.  For the other com-
pounds, either sorption or coulometric factors(H) must account for the
discrepancy.  As is clear from Table 6, where better agreement is seen
with the short column as compared to the long column, a large percentage
of C2C14 error is attributable to column sorption.

Although the tropospheric synthesis of phosgene from halocarbons has been
posulated, we are aware of no previous detection of phosgene in simulated
smog reactions.  As can be seen from Figure 15, phosgene is synthesized
during the irradiation of a mixture of N02 and C2C14 with simulated sun-
light (>2950A ki=0.4/min).  Confirmation was obtained, using standard
phosgene mixtures, with retention data and ionization efficiency charac-
teristics.  The discrepancy between the actual (0.28 ppm) and coulo-
metrically determined (0.1 ppm) phosgene concentration is due to sorption
or heterogeneous decomposition in the column.  Promising research now
underway in this laboratory indicates that this sorption problem may be
empirically corrected for by inclusion of sorption kinetics in the
coulometric analysis.

DC 200 has been demonstrated to be an excellent packing for the separation
and EC determination of ambient CC13F, CH3I, CC12F-CC1F2, 003, CH3-CC13,
CC14, C2HC13 and C2C14 under isothermal (23°C) conditions.  Porapak Q at
80°C and Chromosil 310 and Carbowax 1500 at 23°C were found acceptable for
ambient CC12F2 analysis.  Porapak Q at room temperature is also a very
good column for the separation of SFg and CBrF3.  Carbowax 1500 exhibited
excellent resolution of vinyl chloride at room temperature (23°C).  Phos-
gene was found to suffer unacceptable irreversible losses in all columns
studied except didecyl phthalate.  This column provided excellent reso-
lution at 23°C and sorption losses, even though substantial, were suf-
ficiently small to allow accurate analysis in the sub-ppb range with
frequent calibration.

On a typically polluted day all halocarbons under study could be measured
in the sub-ppb range.  As will be reported later, CCl2F2, CC13F, CH3I,
CH3CC13, CC14 and C2C14 are ubiquitous at their measurable concentrations.
The other compounds may not always be present at their measurable

                                      75
-------
              CM
S3HDNI-1H9I3H
    76
-------
 1 Figure 15
 FSD3XIO  •


   COCC2

       0.28
       PPM
           COLUMN 9, 23°C
           CARRIER (N2)
           FLOW RATE=60m£/MIN
           SAMPLE SIZE 0.4 mfi
      3 X IO"'°A
12345
 MINUTES
     77
-------
    Table  6A. Comparison of Coulometrically Calculated
              Concentrations with calibration Standards

                                  CC12F-
Compounds            CCl-jF  CH3I  CCl2F     CHCls

Cone, based on
Calibrations          0.56  0.05  0.80      0.06    0.83
   (ppb's)

Coulometric
Cone, (ppb's)         0.42  0.04  0.38      0.02    0.16

lonization            0.75  0.67  0.30      0.20    0.30
Efficiency
   Table  6B.  Comparison of Coulometrically Calculated
              Concentrations with Calibration Standards
Compounds            CCl4  C2HC13  C2Cl4  C2C14*  COCl2**
                                                      rf
Cone, based on
Calibrations         0.19   0.75    0.50   0.53   280.0
   (ppb's)

Coulometric
Cone, (ppb's)        0.16    —     0.22    0.39  100.0

lonization           0.80    —     0.60    0.60    0.75
Efficiency
*  This was determined on a 2 ft. long DC-200 column in
     which C2C14 eluted in 13 minutes instead of 33.

** Phosgene is reported as measured in an irradiated mixture
     at 1 ppm C2d4 in air with 50 pphm N02  (50% RH; KI =
     0.4/min).
                               78
-------
concentrations depending upon localized emissions in the sampling area.

The use of purge gas at low concentrations of solute leads to reduced
sensitivity.  This is attributable to a decrease in ionization efficiency
with increasing flow rate through the EC detector.

The utilization of the ionization efficiency as a confirmatory aid has been
demonstrated and further applied to confirm the identity of phosgene in a
simulated photochemical smog study and, accordingly, the probably tropo-
spheric synthesis of this compound.  Because of its high ionization
efficiency (>75%) and instability, the latter making the preparation of
calibration mixtures extremely difficult, phosgene and similar reactive
strong electron absorbers are excellent candidates for coulometric
analysis.  Accordingly, for such compounds, new packings and passivation
procedures are recommended along with a detailed analysis of sorption
kinetics.

The exquisite sensitivity of the EC detector to most of the compounds under
study and their wide spectrum of emission patterns and reactivities make
them excellent candidates for the study of complex atmospheric phenomena.
The methods and data presented here should find wide application in studies
involving point and multisource diffusion modeling, transport of large
scale air masses, photochemical smog and sea breeze modeling and strato-
spheric exchange.

5.2  Gas Phase Coulometry

Under optimum conditions of near 100% ionization in an electron capture
(EC) detector, strongly electron absorbing compounds produce a response
of such .gfeat sensitivity that femtogram (10~15g) analysis has been sug-
gested^^).  In this study a coulometric gas chromatographic method of
analysis based on gas phase electron absorption has been evaluated and
used for measuring the ambient concentrations of several such compounds.
Developed by Lovelock"   ^, this method is based on a 1:1 equivalency at
100% ionization between the number of solute molecules in a carrier stream
to the number of electrons absorbed by them in the EC detector.  Accordingly,
the solute concentration can be calculated directly from the number of
electrons absorbed.  At ionization efficiency of less than 100% the use of
two identical detectors in series enables one to determine the fractional
ionizations in the EC detector and thereby maintain the absolute nature
of analysis by correcting for the unionized molecules.  A further modi-
fication of gas phase coulometry, for use with reactive compounds which
undergo decomposition on the gas chromatographic columns, has been
developed by us.  We have termed it "Pulsed Flow Coulometry" and it will
be described in section 5.1.3.

When operated coulometrically at 100% ionization efficiency an EC detector
is at its maximum sensitivity since all solute molecules are "counted."
Since the method is absolute, sources of mixing and contamination errors
inherent in the preparation of extremely dilute calibration mixtures are

                                      79
-------
precluded.  An additional advantage of this mode of operation, particularly
in air chemistry studies, is the ability to determine the concentration of
an unknown compound and possibly deduce its identity from spatial and
temporal distributions of concentrations.  Furthermore, rate of thermal
electron attachment is an excellent aid for confirmation of identity when
used in conjunction with retention data.

5.2.1  Theory -

The theory of gas phase coulometry is as follows:  Consider two identical
EC detectors in series and let their signals be Xj and X2 in coulombs due
to an injection of a plug of Q molecules of compound AB.  If p is the
fractional ionization of AB, at high ionization efficiencies and low solute
concentrations one can write:

         Xi = pQ                                            (1)
         X2 = p CQ-pQ)                                      (2)
          p = 1 - X2/XX                                     (3)

The gram moles of solute W in the EC detector are therefore from equations
1 and 3.

         W =      Xi _                                (4)
             96,500 (1 - *1)
                         xl

For an injection of V ml of sample at t °C, the volumetric mixing ration
CAB is:
         CAB =
             = 8'5 x 10"4 x
                    Vrl - X2A
                     1
With a recorder the signals Xj and X2 are simply the respective chroma-
togram areas in coulombs.

Ionization efficiencies can theoretically be predicted by considering
the EC detector as a stirred tank reactor in which solute molecules under
go pseudo-first-order reactions with electrons present in large excess.
For a carrier gas passing through the detector at constant flow rate F0
simple mass balance gives :
                 iCVd                                         (6)

where K is the first order constant and Vd is the detector volume.  Veri
fication of the model offers the possibility of determing optimum para-
meters for coulometric analysis.

                                    80
-------
5.2.2  Results -

The ionization efficiencies of the compounds studied are listed in
Table 7.  The functional relationship between peak height and concen-
tration for CC14 and CClsF are shown in Figure 16.  The variations of
ionization efficiencies with flow rates are plotted for these compounds
over a range of flow rates in Figure 17 and extrapolated from one point
through the origin for the other appreciably ionizable compounds (>30%)
of Table 7,  Concentrations determined coulometrically at intermediate
efficiencies of 45% for CC^F and 50% for CC14 are plotted against known
concentrations in Figure 18.  Coulometric convergence to actual concen-
tration with increasing ionization efficiency is graphed for these two
compounds in Figure 19.  A chromatogram for a typical ambient injection
in the New Brunswick area is given in Figure 20 and the corresponding
coulometrically determined concentrations are reported in Table 8.   The
chromatograms for the substances exhibiting greater than coulometric
response as shown in Table 7 are given in Figure 21 and the effect of
varying concentrations on this response is shown in Figure 22 for trans -
CHC1:CHC1.

5.2.3  Discussion -
CC14 and CCljF were evaluated extensively to verify the linear model
assumed in equations 1 and 5.  Figure 16 shows that the EC detector is
slightly nonlinear over the concentration range studied.  With con-
venient sample size (3-10 ml), this range includes typical to three
times ambient concentrations.  Clearly, the profiles approach linearity
at very low concentrations and would appear to limit accurate coulometric
analysis to this concentration regime.  Reference to Figure 18 shows,
however, for at least CC14 and CClsF this is not the case.  The concen-
trations calculated with equation 5 are in fact linear with the standard
concentrations.  This unsuspected result was due to a decrease in ioni-
zation efficiency with increasing concentration.  The practical con-
sideration here is that by operating coulometrically with two detectors,
errors due to non-linearity of a single EC detector were offset over the
entire concentration range studied.  This behavior is attributed to a
complex functional relationship between response, concentration, and
ionization efficiency.  Qualitatively, this can be explained by considering
a  non-linear response, suggested by Figure 16, of the type

         Xi = pQ - m p2Q2                                   (7)

where m is a constant.  Factoring equation 7

         Xi = pQ(l-mpQ) where [mpQ]«l                      (8)

Similarly, the signal in the second detector is

         X2 - P (Q-PQ) (1 - mp (Q - pQ))                    (9)

Defining a detector coulomb efficiency E as the fractional change in

                                    81
-------
               Table?.   lonization Efficiencies3




            Compound               lonization Efficiency
          CC14                            0.90




          SF6                             0.85b




          CC13F                           0.84




          CBrF2-CBrF2                     0.70




          CC12=CC12                       0.69




             I                            0.63
          CC12F2                          0.33




          CH3-CC13                        0.20




          CCl2F-CClF2                     0.10




          CHCl3                           0.06




          CHCl=CCl2                       0.00




          trans-CHCl=CHCl               < 0.00




          CH2=CC12                      < 0.00




                                         <0.00
a_   ,	    	 .     __   2.
                         2
Carrier Flow Rate:  33 cm /min.  Porapak Q Column
                               82
-------
          Table  8.  Ambient Concentrations of
             Coulometrically Determined Compounds in the
             New Brunswick, N. J., Area
      Compound                     Concentration ppb

      CC13F                              0.37

      CH3I                               0.08

      CH3-CC13                           0.27a

      CC14                               0.17
      CrIC -L^CC -L f)
                                         0.12
aBased on an ionization efficiency of 20%.  Not amenable
to analysis (Ionization efficiency = 0) .
Table 9.   Effect of Flow Rate on Detector Responses
    Responses and Efficiencies for CC^F and
Dector
Compound
CCl3F
CC13F
CH3I
CH0I
Plow r.ate,
ml/min
71
11
71
11
.0
.3
.0
.3
response
coulombs
x 10^-0
209
45
135
16
.1
.0
.0
.5
                                             Ionization
                                             Efficiency

                                             0.73

                                             1.00 (.approx.)

                                             0.60

                                             1.00(approx.)
                            83
-------
BH
 fl
u
3
o
 a
 f-
3
        I       1       I       I       I       I       i       1
                                                                         o
                                                                         ro
                                                                          CO
                                                                          CM
                                                                          CD
                                                                          CM
                                                                          VI
                                                                          OJ
                                                                          CM
                                                                          CM
                                                                          O
                                                                          CM
                                                                               UJ
                                                                _J
                                                                o
                                                                               LJ
                                                                          -   Pr

                                                                          (0   <"
                                                                               X
                                                                               ca
                                                                          vr   a.
                                                                          —   Q.
                                                           CM   "
                                                           —   o
                                                                          o
                                                                          CD   y
                                                                               6
                                                                          CD   O
                                                                          CM
 8
S
-
                                           84
-------
                                        LU






                                        OL






                                        O
                                 a
-  CL
-------
u
U
                                                      O
                                                      ro
                                            QV
                                                    -,I0
                                                      C\J
                                                      O

                                                      C\J
                                                         O-

                                                         C.
                                                         O
                                                         o
                                                    -;e  _i
   P

   o
   <


LO
00
d
V
5
•f-
tt.
\
\\
1 1 1 1 1 " '
if) O u~> O ^> c
CJ CVJ — —
   (8dd) NOIlVdlN30N03
                         86
-------
in
C
O
•n o
rtl
C
0)
o
C








o
0 i 1
- I -
2 I V
0 "I
rt
o
•M •
t/) 0)
•P 'H
C 0
6 
C) 'H
fH O
Sl-H
t/1 £4-1
rt FH
4) i (L)
"•)
r
!'
I

H
B
/ .
\
r
1
I
n
1
	


,
)
]i k
e .- ( ft
c i n
00 H
•H -H
?Hft->
+J rt
0) to
e -H
0 C
rH 0
V

J?
I)

i^
r —
a

\
o
0
1
\ 1
CO * f

U rt 1 	
\ ~:'
\ 5

~
O

f^
LJ
• "•
O

i
1
\ |[IB
UJ
2;
o

t _^
M
	
^*^
O











(Bdd) NOI1VU1N30NOD
            87
-------
88
-------
89
-------
100
       • Figure 22  - Effect of trans-CHC1=CHC1  concentration on the greater than
                   coulometric response.
                10         20        30        40        50
                 CONCENTRATION  I PPM  X  SAMPLE SIZE)
GO
                                    90
-------
coulombs X^-X2/X^ as distinguished from the definition of p (fractional
change in molecules),

         E = 1 - £                                         (10)
                 Xl

By substitution of equations 8 and 9 in 10, one obtains by linearization
for the condition [mpQ]«l,

         E = p - mQp2 (1-p)                                 (11)

Clearly, E must always be less than or equal to p.  The latter approached
E at extremely low concentrations (Q-K)), under linear conditions (m-K)),
as p-KL or a combination thereof.  Equations 8 and 11 show a reduction in
Xi and E respectively as Q increases.  The linearity seen in Figure 18
is attributed therefore to these effects which help maintain Xj/E as a
relative constant and thereby permit an extension of the workable coulo-
metric concentration range.  This linearity does not preclude, however,
large errors at low efficiencies.  The coulometrically determined CClsF
and CC14 concentration range of Figure 18.  As the ionization efficiencies
approach 100% these errors become negligible as shown in Figure 19.  It
follows that accurate coulometric analysis requires conditions favoring
maximum ionization efficiencies.  From our data it seems reasonable that
barring irreversible sorption phenomena accuracy greater than 95% should
be routinely obtained at ionization efficiencies greater than 90%.  Errors
of 25% and less can be expected at ionization efficiencies exceeding 50%.

According to equation 6, a plot of the reciprocal efficiency versus flow
rate should be linear.  This is confirmed for CClsF, CC14 and CF^I in
Figure 17.  The linearity allows one to determine an efficiency at one
flow rate and extrapolate it to zero flow rate.  This has been done foi
all appreciably ionizable compounds of Table 7.  Practically, one can
determine with such plots the feasibility and possible errors of using
coulometry.  A large slope indicates poor efficiency which can only be
compensated for by very low flow rates.  A small slope allows flexibility
in the choice of flow rates.  However, although one can theoretically
achieve 100% ionization efficiency for an ionizable compound by approaching
zero flow rate, such flow rates may be imcompatible with practical analysis.
Table 9 gives the detector response at two flow rates for CC13F and CH3l.
The responses are seen to fall off drastically at the lower flow rate,
making the coulometric response invalid.  This phenomenon was attributed
primarily to increased sorption and spreading in the GC column, which
could more than offset the advantage obtained due to increased efficiency.
It follows that one can only reduce flow rates as long as GC response
remains constant or increases.

Figure 20 is a chromatogram obtained from an injection of 8 ml. of ambient
air in the New Brunswick, N.J. area.   Identified peaks are CCl^F, CH$I,
CH3-CCl3, CC14, CHCl:CCl2, and CCl2:CCl2.  The identity of these peaks
was not only established by retention data on different packings (SE30,
Porapak Q), but also was confirmed by their efficiency or ionization.
                                    91
-------
This was found to be a highly reliable method of identification since it
is extremely unlikely that two compounds will have the same retention
times as well as equal ionization efficiencies.   Table 8 shows the
ambient concentrations of some of the compounds  identified in Figure 20.

Hitherto, it has been considered highly unlikely that a greater than
coulometric response (Xi>X2) could be encountered in practice(182)_   jn
this laboratory, CC12:CH2, trans-CHC1:CMC1 and CH2C12 were found to
yield greater than coulometric response as shown in Figure 21.  Figure 22
shows that for trans-CHC1:CHC1 the response of the second detector is at
least 265% greater than that of the first detector.  Since such compounds
are apparently rare, dual EC detectors in series can be used reliable
to confirm their identification.  Further, an increase in sensitivity is
possible by using the second detector conventionally.  Based on the
mechanism for electron attachment proposed by Wentworth^°^), the
greater than coulometric response is attributed to the products of
ionization having greater electron affinities than the reactants.

5.5  Pulse Flow Coulometry

In the course of this study it became evident that certain highly
electron absorbing compounds, which otherwise would be prime candidates
for analysis by gas phase coulometry, presented real analytical diffi-
culties because of their tendency to undergo decomposition on the gas
chromatographic column.  An excellent example of this is phosgene, which
is one of the strongest known electron absorbers (comparable to carbon
tetrachloride).

Previous workers, as indicated below, have reported difficulties with
phosgene analysis due to losses on columns.  For example, Priestly et
al.'   J reported the electron capture  (EC) gas chromatographic deter-
mination of phosgene in air.  Separation was achieved using an aluminum
column packed with 30% didecyl phthalate coated on 100/120 mesh GC 22
Super Support.  Dahlberg and Kihlman^^^) USed a similar GC procedure with
a stainless steel column packed with 20% DC 200 on Chromosorb W.  The
column had to be treated with acetyl chloride to preclude unacceptable
phosgene losses.  A sensitivity of 1 ppb was achieved by both groups.
Jeltes et al.™^' used an aluminum column packed with 30% diisodecyl
phthalate coated on 80/100 mesh Aero Pak for phosgene analysis and re-
ported a sensitivity of 0.2 ppm with the EC detector.

Because phosgene was expected to be an  important product in some of our
photochemical studies, and because of its potential importance as an air
contaminant, efforts were made to improve on the analytical procedures
available.

The wet chemical procedures reported in the literature for the deter-
mination of phosgene vapor have been reviewed by Kolthoff et al.0-85)
and Jeltes et al.^lj.   in general, they suffer the typical difficulties
associated with wet chemical procedures, namely, lack of specificity,

                                     92
-------
interferences, losses in sampling lines and the requirement of large
samples precluding real time analysis.  Furthermore, such methods are
often elaborate and require considerable experience for acceptable
accuracy.

Because of its reactivity and the problems associated with wet chemical
methods, phosgene analysis is best accomplished by on-site GC procedures.
The three columns used by Priestly et al.^70)^ Dahlberg and Kihlman(l84)
and Jeltes et al.^1'IJ^ based on our experience, require routine cali-
brations because of the extreme reactivity of phosgene which causes
variable column losses, depending on the column's history.  Clearly, an
absolute method not requiring calibration or suffering from changing
column characteristics is desirable.  Reported here is an extension of
absolute coulometric analysis which empirically corrects for column
sorption through the use of pulse flow kinetics.  For brevity the method
is called pulse flow coulometry (PFC).

5.5.1  Theory -

The theory of PFC is as follows:  In the absence of column losses, from
equation 1 above we can write

         Ce (ppb) = Ci (ppb) - 8.5 x 1Q5 (275 + t) Xj

                                     - ^ )                 (12)
where C^ is the inlet sample concentration, Ce is the exit concentration
expressed as the analogous mixing ratio of eluting C to V ml of mixture,
and KI and ^2 are tne respective serial EC detector responses in
coulombs.  Use of equation 12 leads to accurate analysis only at high
ionization efficiencies (1 - X2/Xj) provided no losses take place in
the GC column.  Reactive compounds such as phosgene, however, exhibit
a significant loss in the GC column requiring the novel application of
PFC for absolute analysis.  In this procedure a pulse of the reactive
constituent is studied by coulometric analysis of the exiting constituent
to obtain the decay kinetics in the column.

Consider a packed column of length L and cross-sectional area S through
which a carrier gas flowing at a velocity u sweeps a slug of a reactive
gas mixture, say phosgene in air.  For conditions of no axial dispersion,
mass balance gives the instantaneous moles of phosgene traversing the
column in time and space as,

         9C     9C   8C*     , ^
         at + u 9! * 3t~ = - W
where r is the rate of reaction of component C in the GC column, C* is the
absorbed moles of C in equilibrium with the vapor phase, t is the time,
and 1 is the length along the column axis.  Assuming first order kinetics
and a linear adsorption isotherm one can write:

                                    93
-------
          (r) = kC                                            (14)
          C* = AC                                            (15)

where k and A are the first order rate  and  adsorption constants respectively,
Inserting equations 14 and 15 into  13,  one  gets:

          3C    u  3       kC
                     _
         3t   1+A 91 =  -  1+A

For the present model the following boundary conditions (B.C.'s) are
valid:

         at t = 0,  C = 0 for 1 > 0                          (i)

         at ,   n+  r   W (t) for t > 0
         at 1 = 0 , C = {                                   (ii)
                        0    for t < 0

The solution to equation  16 with B.C.'s  (i)  and (ii)  is given by Singh
et al.(4 ):
         C = W  (t -      +3 exp  (-    -)                      (17)
         Weight  (or moles) of C  out  of the column   Ce(ppb)   Jo  •._•,
              T  MO.AI
      JoW(t - L  l1+AJ)dt   =  J°W  (t)  dt,                      (19)
         Weight  (or moles) of C  in  the column       Ci(ppb)   
                                                                0 W(t)dt
                                                             (18)

Since
      JoW(t - iL_
                 u
inserting equations 17 and 19 into  18,  it  follows  that:

         Ce                      kV
         £7  = exp  (-|Sk) = exp  (--p^-)                       (20)


where Fo (uS) is the carrier gas flow rate and Vc  (LS)  is the column
volume.  Equation 20 can be rewritten as:
                      kvc
    In  Ce = In  C- - ^—                                    ,01,
                      f Q                                     V^iJ

5.5.2  Results -

Standard samples of phosgene were prepared at several concentrations  (10
to 167 ppb), and each sample was injected  into the GC at several known

                                     94
-------
carrier gas flow rates.  Equation 12 was used to determine the column
exit concentration at each flow rate.  A plot of In Ce versus 1/FQ was
made for each standard sample, and the intercept (C-jJ was compared with
the standard concentration.

Individual dual EC chromatograms of CC13F, CC14 and CC12F-CC1F2 are shown
in Figure 23 for standard injections of air-halocarbon mixtures prepared
with their respective permeation tubes.  A comparison of the standard
concentrations with the coulometrically determined concentrations for
these compounds at their indicated ionization efficiencies is given in
Table 10.  Figure 24 is a plot of phosgene permeation tube weight versus
time.  Presented in Figure 25 are chromatograms of replicate injections
of a standard phosgene mixture.  Figure 26 shows semi-log plots of Ce
versus 1/FO for several standard concentrations of phosgene.  A used and
a freshly conditioned column were employed in these experiments.  A com-
parison of the standard concentrations with those determined by PFC is
presented in Table 11.  Figures 27 and 28 show the variation of ionization
efficiency with flow rate and input sample concentration respectively.
Figure 29 is a plot of phosgene decay in a conditioned glass vessel in
the presence and absence of water vapor.  Also shown in Figure 29 is the
dry phosgene decay profile in a ground-glass vessel having a large spe-
cific surface area.

5.3.3  Discussion-
Coulometric analysis can be used for the absolute determination of elec-
tron absorbing compounds which do not suffer column losses.  This is
illustrated in Figure 23 and Table 10, the latter of which shows less than
a 15% error between standard ppb injections of CCI^F and CC1$ and their
coulometrically determined concentrations (equation 12).  For compounds
exhibiting low ionization efficiencies, however, significant errors
can be expected as is demonstrated by the 82% error for CC12F-CC1F2
analysis at a 28% ionization efficiency.

The reactivity of phosgene suggested the use of a TFE Teflon Permeation
tube, as a primary standard, for the dynamic preparation of ppb phosgene-
air mixtures.  After a few days of conditioning, the tube exhibited a
constant rate of weight loss (Figure 24) and provided an extremely
reliable phosgene output (Figure 25).  Figure 25 further shows that
phosgene is an excellent candidate for coulometric analysis because of
its high ionization efficiency (>85%) at a convenient carrier flow rate.

The assumptions of a linear adsorption isotherm and first order kinetics
for phosgene - column reactivity are proven valid by Figure 26, where
semi-log plots of C  versus 1/FO are shown to be linear (equation 21).
As developed in the theory, the intercepts of these lines are the inlet
phosgene concentrations (Ci).  From Table 11, PFC concentrations are
seen to be in very good agreement with the standards (maximum error =
10.2%). . This is attributable to the use of ionization efficiencies
exceeding 75% and the inherent applicability of the assumed kinetic
model.  Since the lines are parallel for a given column (Figure 26),

                                    95
-------
CM

U-
u
u
                                                    o
                                                     '
                                                    CVJ
                                                    o
                                                    co
                                                    <£>'
 2 -
 00 M
 8
(LI O
  V
•-I p.
rt in
3 <0
a a:
CM

O
I*

3,
*rH.
U.
                      O
cc.

UJ
        o
      .0 O

  -   £g
u- JH2 ^t^
 rozi w^
«" 2m
           <
           o
Ih'a-l
u
o
  cvi
LJ

UJ
o:
                                    CJ
                                      LU
                                      O
                             Ld
                             O
                            96
-------
•5
                         97
-------
c
u
el
tn
o

£


•8
a
TJ
c
a
                                                                                                 q
                                                                                                 ro
                                                                                               J32
                                                     98
-------
  300.0 r-
   100.0 j—
 o>
O
Q.
Q.
O

O
O
LJ
O
CO
C
X
Q.
C.GO     0.01
                                                      !67ppb(S.C.)
                                                      80ppb(S.C.)
                            0.02      0.03      0.04     0.05     0.06


                               '/F0  MINX mi
                                       99
-------
   1.8

   1.7

   1.6

   1.5
I
P  1.4

   1.3

   1.2

   I.I

   1.0
Figure 27  - Variation of lonization Efficiency
          of Phosgene with Flow Rate.
      0   10   20   30   40   50   60   70   80
                  CARRIER GAS FLOW RATE
                     F0  m0/MIN
                       90   100
                                 100
-------
          q
          cd
          CO
f.
4->
•H
 0)
 M
 t/1
 o
f.
O.

M-i
 O

 X
 o
 u
UJ

C
O
• H
•P  C
rt  O
N -H
•H 4->
C  rt
O  (H
1— I 4-)
   C
4-1  0)
O  O
   c
c  o
o u
•H
•P  0)
rt i-i
•H  PH
fH  6
rt  rt
oo
CNJ
0)
JH

a
• H
U-,
«   s
 c   O
 C   CO
UJ
NJ
(S>
l±J
^   °
I   52
<
C7)
X
•a
 O-
CO
q
cd
           o
                                                        CO
                                             •             •
                                            o           o

                           d  'AON3I01JJ3  NOI1VZINOI
                                                                       q
                                                                       o
                                                                       CJ
                                                             o
                                                             o'
                                                             o
                                                             0  P
                                                             d  e
                                                             CO  LJ
                                                                 Nl
                                                                 C7)
                                                                 UJ

                                                             O  5
                                                             q
                                                             c>
                                                             CJ
                                                          LO

                                                          O
                                                                 -a
                                     101
-------
            Figure 29 - Phosgene Decay in a Conditioned Glass Vessel in Presence and
                      Absence of Water Vapor,  and in Contact with a Ground Surface.

                                    MINUTES
c.00.0
                 50
                   100
   150
 200
—I—
 250
—r~
 300
—r~
       t
  100.0
•--.
li -a
„•> a.
CO Q-
O —
   10.0
—    o
                O  O
                                  DRY AIR  i   AIR WITH 785 ppm

                                        "**•   WATER
350

   30.0
                                              10.0
                                                                                 o
                                                                              —,  ui
                                                                         o

                                                                         CL
    ..0
                 20
                   40
   60

MINUTES
 80
 100
 120
                                      102
-------
     CD
    •D
 tn  M
 C  fO
 O T!
 •H  C
 -P  fO
 m .p
 M CO
 -p
 C  0
 CD JQ
 u  D
 C E-i
 O
 0) -P
 c  ro
•H  a;
 e  e
 M  M
 CU  (U
-P Oi
 (U
P rC
    .p
rH
 (0
 O
•H
 M  U
-P  y
 0)  T
 e  &,
 O   C
rH  rH
 3  U
 O  CJ
      CM
                    W
                U  C
                -H  O
                M  -H
                -P  -P
                i
                o   u
               -H   C
               -P   CU
                m  -H
                N   U
               •H  -H
                C  4-1
                O  'W
               H  W
o

o
                                          (X)

                                          o
               CO
               CM
o
rH

(U
10
EH




fa
1
F~l
U
u





^
_J
i^n
o
0
CM
fa
i-H
u
V
fa
CM
1
i^n
u
u
                                                           10."
-------










,G
-p
•H
to
C
o
•H
-P
id
v^
•P
c
0)
o
c
o
0
0)
c

id
M
JJ
C
U
G
0
U

TD

-P
(d
iH
£5
U
i-H
id
0

i

K
CM


























^i
O
c
a>
•H
0
•H
4-1
M-l
W







^





'O
0)
4J
id
r-f
3
U
i-H
nS
U









TD

id
•0
c
id
-P
en


c
G 6
5 3
rf 	 1
CD
4J
C
(I)

£•
O
U







0)
tp
G
fd
oi






vi
o

S_l
M

to
c
o

•p '-^
(d ,0
M a
-P Q.
C ^
QJ
O
C
O
U




to
c
0
-H
4J
id -<
M ^2
-P a
G d
Q) ^
U
c
o
CJ
,J » — 1
r-l O
o o
U
= = = = JC
T3 tfl
a; cu
to M
P fc






mo in o
co co r~ co
• • • •
00= = o o

A A* A A
a, a a a






O vD O O CN O
......
^f in in in o in
r-)







vD O O O O O
• !••••
CS^ ro CO vO O *»O
n m r~ in r*
•H











0 0
o o o o o o
......
o in o o r» o
r-i m tj« oo vo co
r-l









;










in
r->
•
o

A
a






(N
•
O
i-H







O

o
in
r-t












O
•
r-

r-H



104
-------
once the slope of one of them is determined, analysis is possible by a
single injection at one flow rate.  The inlet concentration C^ would
then be determined as the intercept of the parallel extrapolated line.  It
is recommended, however, that the slope of an analysis line be routinely
checked.  The rate constant k may vary gradually with column history as
is suggested, in the extreme case, by the different slopes of the lines
obtained for the used and the conditioned columns.  In conventional GC
procedures a change in slope would correspond to a need for a new cali-
bration whereas in PFC, the analogous requirement would be the injection
of an unknown sample at a few flow rates.  This is substantially simpler
than a rigorous calibration, particularly for reactive gases like phosgene.
Since there is evidence'-" >^^ ' that carrier flow rate and solute mass
are the major factors governing the ionization efficiency and hence the
accuracy of the analysis, the effects of these variables on phosgene
ionization efficiency were studied.  A linear plotf ^ >182 ) of the
reciprocal ionization efficiency versus flow rate (Figure 27) shows that
an increase in ionization efficiency can readily be obtained by reducing
the carrier gas flow rate.  At a given flow rate, however, Figure 28a
clearly demonstrates that the ionization efficiency is nearly independent
of the input solute mass up to about 0.1 ng.  Beyond this the ionization
efficiency is seen to fall off, presumably because of the decreasing
ratio of electrons to solute molecules (Figure 28b) .  Consequently, in
the regime where solute mass has an effect on the ionization efficiency
(>0.1 ng for phosgene), the latter can be increased by a reduction of
solute mass as well as of carrier gas flow rate.

Having established the validity of PFC for the absolute determination of
phosgene in air, the method was used for a preliminary study of phosgene
vapor stability in glass vessels.  A 560 ml cylindrical glass vessel
(45 cm x 4 cm i.d.) was flushed with a 167 ppb mixture of phosgene in dry
air for 60 minutes and was then capped and allowed to stand at 23°C fox
subsequent analysis.  Figure 29a shows the first order decay of phosgene
in this system.  After three hours, water- saturated air was injected into
this vessel by syringe to bring the water vapor concentration to 785 ppm.
It is clear from Figure 29a that water had, at best, a minimal effect on
phosgene decay.  Figure 29b shows a much faster decay of a phosgene-air
mixture in a vessel of much higher surface area (ground glass), indi-
cating that the role of water, if any, is manifested in heterogeneous
surface reactions.  Further, in tropospheric photochemical smog simu-
lation experiments where phosgene was synthesized from C2C14 in 200 liter
Teflon bagsC  ), it was found that phosgene concentrations remained
stable for periods exceeding 15 hours in the presence of 10,000 ppm of
water vapor.  We attribute the absence of surface reaction here to the
passivation of the walls by photochemical reaction products (CClsCOCl,
COC12, HCOC1, CC14, Cl2, HC1, etc.).  These results lend support to
the observations of Noweir et al.(186) that the importance of phosgene
decay by the gas phase phosgene - water reaction has been overemphasized
in the literature.
                                  105
-------
                               SECTION VI

                          AMBIENT MEASUREMENTS

Reported here are aerometric halocarbon and SF£ data obtained during
several programmed field studies initiated since March 1973 at various
locations in the U.S.  which should be representative of a wide gamut of
emission patterns and  meteorological conditions.  The compounds included
in these studies were  CClsF, CC12F2, CH^CCl^,  CC12CC12, CC14, CHC1CC12,
CH3I, SF6, CH2CHC1,  CHC13 and CC12F-CC1F2.  Of these, several were sub-
jected to simulated tropospheric stability studies.   Compounds that were
found tropospherically stable were tested for  possible stratospheric
reactivity.  Correlations between ozone and halocarbon concentrations
monitored at a non-urban location were used for the  first time to
demonstrate the feasibility and utility of tracing large-scale air
masses for elucidation of photochemical smog phenomena.

6.1  Results
Figure 30 shows the locations of the eight monitoring sites.  Table 12
presents the complete data for levels of all the above compounds at
Seagirt, N.J.; New York, N.Y.; Sandy Hook, N.J.; Wilmington, Del.;
Baltimore, Md.; Wilmington, Ohio; and Whiteface Mountain, N.Y. for the
dates and times listed during summer and fall, 1974.  Also given in
the table are data for Bayonne, N.J. taken from March to December, 1973
for all the compounds except SF6 and vinyl chloride for which analytical
procedures had not at that time been perfected.  Dashes in this table
indicate that analysis of the compound was attempted, but the level was
less than the lower limit of detectability.

Table 13 lists the maximum, minimum and mean values observed for these
eleven compounds at all eight locations.

Table 14 shows representative levels in urban and rural areas, as well
as the halocarbon levels associated with an inversion.

Table 15 lists the daily mean and monitoring period mean ambient levels,
and their standard deviations expressed as a percent of the mean.  Be-
cause of the relative infrequency of monitoring at Bayonne, daily mean
values are not listed for this location.  Instead, monthly mean values
are given in the table.  Also indicated in this table are the number
of observations at which detectable levels of the compounds were present.
It should be noted in using the mean values in Tables 13 and 15 that
only those measurements at which detectable levels of compound were
observed are included in the mean,  in some cases, using this procedure
undoubtedly gives a mean value which is too high; however, including zero
readings in the mean would, especially in the case of the non-ubiquitous
compounds, result in some of the "mean" values being less than the
minimum detectable level.

Table 16 shows for each compound at each  location the precentage of

                                   106
-------
                                                8
o
                                107
-------
CN
                                 in co





m
(U
5
•H
^
cn
3

(0 PH
^ (D
JJ C
rO
C/)
m -p
rH •£
0) 10
(4 4J
10
1 1 t~\
4J (H
0) 

in in VD
p^ r**" CN oo oo in o^ o^ ^j* VD ^* ^*
inin^^^COCNCNrHrHrHCNrHrHrH





co m in
VD ^N in r^ vo vo VD
OrHCNrHrHtHrHrHrHrHOOOrHOO
CN

inm mcNcN CNCNCN r^-r-cNt^
vDr^roininmo^^'in^'cyicNcNcocN
CNCNrOCOCNCNrHCNCNCNrHCNCNCNCN


incoc^ ro^CNCNinroTtro
cNrHin OrHr*"tx>t**vD^jiinvDCOvD
iHrHrHCNrHrHOOOOOOOOO



CO V0
rH O vD vD ro
OOI 1 1 1 1 1 1 IOIOIO
. • • • t


rH ro vo in in
O rH rH O O
OIOOI I IOI IOI 1 1 1
1 • • . .




m r> in in in
CN co P^ m vo in r^- CN in co 0** r*^ i — i r^»
rf^CNincNCNrHCNCNCNrHrHrHCNrH
ommoomomoominininin
CO ^* rH CO O rH O » — 1 m rH CN ^* O CO ^*
vDvDQOCOCNCNrominvDvDvor~r~-co
OOOOrHrHrHrHrHrHfHrHrHiHrH

CT>
rH
"^v
VD





                              108
-------
 W
 cu

•H
EH

 CO
 D
 O
•rt
 H
 (0
A -P
   m
•P Q
c
0) 0)
•H -P
•us
< a

 vOO
fe U
CO
 C  W
 a  c
    o
 C -rl
 O -P
A  (0
 V)  U
 (0  Q
 U iJ
 O
rH -O
 m  c
K  (0
CM
r-H
 0)
rH

•8
 E-i
(U
.,-1

o
5
u


^*
rH
O
CM
U


ro
i-H
U
CM
u
*
rH
o
u


E-i
rH




ro
rH
u
u


rH
ro
a
u


rH
rH
fa



0)
g
•H
£_|



cu
1 1
ro
Q



0)
u
ro
r-H
a.



i i




in CM
^^* r^
rH CM




m ^i*
CM 00



en
ro CM



vO ^d*
^ ^





rH
0 1



VO
O
O 1



*
rH
CO CO
0 0


o m
CO rH
vD t*»
00
*
CM


r-
CM
\
vO




w*
s M
0) O
S3 r^



1











VD
CN


«
vo
rH



00
in






i





i



in
ro
ro


O
CO
00
0












>
4J
•H
U
-a
Q,
O
rH
V



in
r^
en




in
in


rH
CM
CN



in
CD






1




ro
0




00
ro


O
CN
en
o












i



•a
a
o
rH
V




1
1





ro
rH

in
rH
ro




in

rH




1





1




00
CM


O
O
rH
rH
















X)
a
o
rH
V




ro
ro
rH




ro
r-H

in
rH
ro




VO

rH




1





1




00
rH


O
O
CM
rH
















ft
U
a
r-H
V




ro
ro





H
rH


rH
CM



^*
CM

rH




1





1




in



0
m
^*
rH



















1 1





O
O ^J*




ro m
en o
rH

in en
vO ro
CM CM




CO rH
O.
•
O



co en
** CM



in
rH i-H
0 O



"31
vO vO



o m
in ^
vo vo
rH rH
















_Q rQ
p. Q.
a a
0 0
1 1 rH 1 rH
V -V




rH VO CM 
P" VO ^* CM
CM ro ro CM


00
vo in in
ro in ro






1 1 rH 1



ro ro CN ro
O O ro o
O O O 0





. ""! § °i
rH rH

o o in o
o o <* ro
en rH CN ro
O rH rH rH




00
CM
>X
vO

1












in
CM
rH
•
II

CN
rH
1
ft,
i/\
U 1
CM*
•VO
rH
II
in
CM r-
rH •
I _ j
I r-l
II

* CM
ro H
i
i
m »
• in
o
II 0
r\j
rH II
1
&4 VO
» CO
in
CM
file
^J9
•in
II
ro
•H
H m
^
ro
(N II
(N
rH
-------
























•
u
(N
rH
Q
a
EH



























CM
rH
1
CH
^
rH
O
u
ro
, 	 |
y
K
CM
u

•<*
rH
O
O
^
rH
rH
CO
rH
QJ
HI
o
ro
rH
rH
fa

r-t
ro
K
U

rH
rH
1

0)
e
•H
|H


Q)
4J

Q


0)
O
(0
rH
DLI


1 1

in
co r-
vo m



ro ro
if ^*
• •



CO rH
ON ^J1

VO
m co
CM CM



1 1

00
in ro
O 0
• •

VO CN
in co
o o




CO CO
O/—V
VJ
in m
rH rH
0 rH
rH rH

*
rH
CN
V
p-


^1
*O ,14
C 0
flj O
co ffi


1

in
CM
vO



"31
ro
•



0
ro

in
CM
ON



i




i



I
1


vo
CM

in
i— i
CM
rH















1 1


*fr in
*tf ro
rH




1 1



VO CT*
CM CM


CO rH
rH rO



1 1




1 1

r-  ^3*
CN CO

in o
rO rH
ON VO
rH rH

















in
CM
ro





1



vT>
rH


in
rH



1

in
p~
rH
•

-*
^J1
o



rH
CM

in
^*
0
CM















1


m in
CM rH




rH
1


vo vO
!"•» P"»
H rH

CM
rH
rH rH
in
H CN
0 O
• •

in
rH ON
rH rH
• •

ro in
VO CM
O O


in vo
r- r-
rH rH

m in
ro O
H ro
CN ON














^* ^1* ^
1 II < 1 • 1

co in m
in  | I


m en
r^vOvTi'* COrHVOCOvO
rHOM^rrOCOrOCMCMrHVD

co m in ^r vo m
cooMOOMinrHininvor^
OrHOMrHCMOMONCMrHrH
in
ON
0
1 1 1 1 1 1 1 1 • 1


ON
O
1 1 1 1 1 . 1 1 1

m ^« o*> vo
ro vo m o co rH in
OrHCOrHrHO OOO
• •/"**•••! •••
• • ^J • • • 1 • • •

vo m in
r- Is* in ro r- in
rHrHCOCNinmCNCM^l'ON

ininin^inmoinr^cMin
OinO^frHCMCMrOOrH^t
rHror*r»-vTitTiHrHinvor>
OOOOOOrHrHrHrHrH

* *
CM ro
ro
\
r-









i i

in
CTI r~
ON ro



^j< in
ro CM
• •


•<* CM
vo in
rH OM

ro
CO ^t
rH OM
in
CM
o
• 1




1 1

m
ro
CO O
O.
•



CO CO
l~\ f~\
\J VJ
0 0
rH rH
CTt CM
rH CM

£
r}1












1


Tf
^


in
r^
rH
•


in
vo
CM

in
ON
ro



1




I

ro
VD
O




to

0
i-H
ro
CN














in
o
0
10

CO
ro




^3*
O
0
II

vo
CO
+
OM

m
rj
•

%
^
»
r««
•
o
CO

CN
cn
m
*
ON
rH
1
1
ON
\
r^

C m
O o
o
0 •
o
CO II
rH
vD
f i fV(
< CO


* *
rH «*















































f.
&,
P^

Lj
cd

t/>
•*-•
•H
p;

110
-------






,
o

rH
rH
fa

rH
co
a

rH
H
1
V
E
•H
EH


0)
•P
m
Q


0)
u
m
r-l
cu
1
CO

1

vO
F~
rH




m
rH





1

tn
CM
O

in
CN
in
in
o
o
o

*
rH

^V^
r~


^i
-0
C
m
03
o
o
*
1
in in
r* CM
CO CM
in
CM
• 1

*
vO 0
rH CM




in CM
rH rH


in in
CM CN
O O
* *


in
o
_ i
• i

in m
r- co
o o
rH rH
rH CN
0 0









^
O
o
a
i i
CO | ,
*
tn m
CM CN
CO CO
• •

«•
CN VO
CM rH



VO
in m
rH rH


in
in CM
0 0


r- co
CO CM
0 0

in
vo r-
<# ^fr
m o o
rH <* O
CO CO VD
O O O













1 1
1 1
in
CM m
CO rH
• i •
in
CN
^*
• i i

ID rH VD
00 m rH
•H rH rH



VO
in en en
rH O O





1 1 1

VD VO
rH O
tn o o

m
in CN oo
CO rH rH
o ^J* m
CO ^ CN
en in vo
O rH H













CN
rH
O
CO
rH

1

<*
vO
H



CM
H
rH


CM
H
o
•

in
o
o

in
CM
CM
in o
^j* co
vo r-
rH rH













1
CN CO
• > 1
CO rH
in
CN
CN
1

1 1

•*
O
CN 03
• O



CO vo
0 0



vfi
m
t

00
o
o 03

r»
r-
rH CO
o m o m
O Tj1 O rH
oo co cn ch
rH rH rH r-H

*
CN










O O
o o
CO
• 1 1
rH
in
VD CM
VD CM

1 1

rH CO
r> o
rH rH



^ *3"
C7> CT>
O 0


m in
CM r~
0 0


CTi CO
rH O
O O

m o
r- o
rH CN
in co in
rH CN ^J"
O 0 CN
CM CN CN













0
o
• 1 1
1 1 1
in
rH
• 1 1

1 1 1

in oo oo
oo co r-
0 O 0



CN r-
CO rH CO
O H O


in in
CN CN
o o
1 • •

in in ^
CM CO CM
o o o


CN rH O
rH rH rH
in in in
co in m
O CN CO
o o o



in
v^
r~»







o
0
i
i i
i i

i i

CO CO
tn o
O rH



VD
in o
O rH


in
CN
o
1 •

00
** CN
O O

CO
CO
O3 rH
O.
•
r- o
CM O
rH VD
rH rH
*
CO











1

1

vO
CO
O



CO
^»
o





1

Tj
CN
O

CO
VO
rH
rH
in
tn
rH













VD
rH
o

II
m
i
o
*
CO








CO
vD
O
II

co
rH
U
*
CM



CM
O
4

II

CO
rH
r\
a
o


*
rH

































JD
P<
^
<0
rl
CO

4J
•H
c

111
-------
  VO
•
CO O H O

CO CM CO
rH H O rH
O O O O
....



rH in r- rH
vO O C"> VO
iH rH O rH

o m tn m
O rH O **
CO VO rH CO
rH rH CM CM
* *
rH CM


CO
X


1
y'i ^^
C 0)
•H Q
e -
rH C
-H 0
S 4J
m in
r* in in CM
O rH rH CM
. 1 . . I

in
vo r»
in rH rH
1 ... 1 I


CO in CM rH VD CO
C^ CO 'f CO CO VD
O O rH i-H O O



r*- vo vo co
r» co m co in "cj"
O H rH rH O O

CO
rH rH O
o o o
III..



m co
'd* rH t^ ^
rH W CM rH rH rH
. o • • •
mooininomincoo
^OOCOi-HrHrHCO'J'O
rH^fVOCOCMCOrHrHrHrO
OOOOHHCMCMCMCM




C^
\.
r^










1




i



CO
o



^"
vo
o

CO
rH
o





rH
rH

O CO
in CM
H O
O rH



0
i-H
X









i-H
in
i > i




i i i


in rH rH
r- r- t>
o o o



00
^j* r*1* ro
O 0 0

00 CO
rH O
0 O
1 . •



m
c^ o o
O rH rH
• • •
co o r^ o
co CM co m
O CM CM ^
H rH rH rH




























O
in
rH

II

H
o
rH
»^1
C
••H
>
*
CM









vo
CO

II

rH
O
rH
C
•H
^

*
rH
                                                                                                     0)
                                                                                                     H
                                                                                                     oj
                                                                                                     t/1
                                                                                                    *->
                                                 112
-------

VD
fa
to

CN
H
1
fa
<*
rH
f)

O
CN
rH rH
0 O
• *


in
. i

in
r-
o
. i
• i
n
o
0
•


m
*


in
CN


VD
O
O
•

in
CN
•


in
rH


in
0
o
•



1




1
1
VD
O
O
•


CO
*

«
00
rH





1



1

IT)
CN
CN


in
o
0


in
CN
•


CTi
CN


vD
O
O


in
CN
•

in
CN
CN


I-*
O
O




1


in
rH





i i

in
CN
i •

in
r».
o






00
o
*

II
rH
•H
fa



CO
       lilt
                         I   I    t
                                       I   I    I   I
                                                             ro


CN
H
0)
rH
f\
•8
CN
U
O
rH
iH
rH
CO
T*
U
rH
O
VD
in
0
CN
o
O

ro in
vD CN C7i
O rH O
CO
•^ CO CO
0 O O
l l l

c* in
M ro
fH rH
rH in
CN rH
VO CN
O rH
o o

rH
in
rH
rH
CN
o
o

vD
in
rH
o
CN
o
o

00
o
CN
rH
CO
rH
o

CO
CN <*
iH rH
00 ^fr
0 0
00
O rH
0 O

CO
CN
H
in
CN
rH
VD
O
o

iloride =
t*-i
o
rH
c
•H
*
CN

rH     in  00 rH  ro
rH     CN  oo m  r>
 I      rH  O CN  CN
fa       .   .   .   .
                 VD  m
                 t^  Is*        00  in rH  rH
                 CNCOCQCnvDrHrHrH
                   .   .  o o   •   •   •    •
                                                             (U
 0)     in  in H  vo
 g     O  CN CN  00
-H     CO  CO fN  CN
 &     rH  H CN  CN
     *  *  *
     rH  CN CO
                 comcovocoincoin
                 ^^•OrHOiHinm
                 rHCNVDvOr^OrH1*
                 OOOOOrHrHiH
                                                             O
                                                             iH

                                                             ff
                                                             O
                                                              c
                                                             •H
 0)
4-1
 a
Q
                                                             in
                                                             CN
                                                             o
                                                                    PH
 (1)
 U
 a
rH
O4
    "Q
 I   2
•H   •
4J  
-------
o o
                                              O O




















•
fh
CN
r-i

 m rH in co m
rH O rH 01 rH rH rH
• • • • • « «




rH in in  cr\
CN CN r-4 CN r~ o o
o o o o o o o
» • • • • » •





in vo
1 O rH
0 0
i ..ii i i




o in o co r* m in
rH rH VO VO (7» fN CN
rH rH CN CO O rH rH
• • • • • • »





coiH^co^inoovoooioinou^ooio
rMfOCNrOrotOCNCNOOOinrOO^^rHf^iH
00 CO 0^ ^^ ^1 ^M ^3 r~H ^i* *^3* CO ^3* l^ l^ ^D ^^ CO ^^

* * * *
rH CN CO Tt
 rH
• w y
(QMS
Cj (-« ^1
M pw ^ "
r^ O
in
VD m »
rH 't rH
ro H n
rH O
III 4J •
4-> (0
1 O •»
c m VD
•H Tf rH
^ rH •

4c
rH


















































Q
P.
&

j_!
cd

V)
+J
•rH

s 3
                       114
-------
     vO
    fa
    CO
                                                             0 0
CM
fa
                             CO
                             o
                                    0  O
                                                                           O O
°CM
O
               in
               CM
               o
             i    -   i
                                  i   i
                                           00  CO
                                           O  O
                                                       i   i    i
rH
u
CJ
            r- r-  vo
            rH rH  rH
                    rH  VO

                    00  CO

                                                                       VO
                                   CM
                                   rH
                                in o
 
-------
VO
                       O O
o  o
















*
H
CN
H
(U
H
Q
(0
EH
























CN
rH
1
CJ
CN
U
••1
tt}
CN
CJ
•tf
rH
CJ
0
r_,
•H
i-H
rH
rH
.U
33
U
ro
H
r-l
fc|

rH
K
U
i-H
rH
|
b
Q)
e
•H
E-<

0)
4J
(0
Q




Q)
o
(d
rH
CU
CN
VD
O
• 1

ro
vo
1

O CN
r^ r-
ro CN
* *
rH VD
co m
O O
• •
rH
ro CO
O 1-
• •



1 1



1 1
<* c*
"vf ^
rH rH
• •

H £
0 0

co
CN
\
r^

1
tr>
C
-H
e -
rH C
•H 0

CO
0
• 1

1 1



1 1

•tf ^
^ in
rH rH
• •
in VD
VD in
0 0
' '



l i
in en
CN O
0 0
• •

rH
o
1
en m
rH CN
rH rH
* •
^5 ^2 @^ r**
$ rH rH CN
O rH rH rH










O
•rl
f]
O
in
rH
•

CO
o
•

^
ro
CN
•
H
CO
CN
•



1
0>
0
o




1
0
en
rH
•
ro
3
rH














O
in t>
CN
•

in
CN
•

cr>
VO
CN
•
«tf
^*
rH
•
CN
rH
0
•
cn
o
o
•



1
o
CT>
rH
•
CO ^D If) ll
CN rH l-l C
ir> f» r~ c
rH rH rH r














rH rH rH
fl • •

VO CO CO
rH O 0
• • •

^j* ^^ ^^
r** "^l* ^j*
rH CN CN
t • •
tr. <* rj-
r~4 ^> ^*
rH i-H rH
• • t
CN CN
r-l rH
0 O
1 •
CN
rH rH CN
0 O O
• • •



1 1 1
in r~ en
t*' CO rH
rH rH rH
• • *
n m o in m
D "rj» f>J \f) ^
0 CO rH CO O
H rH O4 CN O

^J1
CN
\
r-









ro
rH
•

CO
0
*

(^
ro
CN
'
•<*
^*
rH
•
CN
rH
O
•
o
rH
0
•

0
0
•
O
VO
rH

O
3
0














<*
rH
•
CN
ro
•

in
CN
•

in
in
ro
•
rH
CO
CN
'
rH
ro
0
•



1

O
0

0
""J"
rH

0 0

O 0














in
CN
*

VD
rH
•

in
CN
ro
•




CN
rH
0
9
CN
f\|
O




1
in
CN
rH

O
3
o














<*
rH
• 1
in
CN
*

in
CN
•



ro
t
r^.
ro
CN
•
CN
rH
0
•
CN
CN
O
•



1
^
CTi
O

in in in o o
3 In $ £ °
O O O O O















































^
o
*— *-
a
0)
crt
to
in
4->
•H
C
3






                                 116
-------
       vD
      fa     O
      05

      M
      rH
       I
      fa
                      O  O
                                            O O
                                                          O  O
           00
           O
                             O  O
                                                   CD
                                                   O
                                                                 O  O
o  o
 CN •
u
                VO
               O O
                                     i   i
                                                       in
    OJ
u
u
               (NJ M
               CM C>J
                                    00  CO


                                    rH  rH
                                      •   t
EH  •<*
rH  •*
i-l  f-l
               O rH
               rH rH
                                          O  rH

                                          rH  rH
                                           •   •
  CO
rH
U
                I   I
                                     I   I
                                                      cs
                                                      rH
                                                      O
QJ

,Q    H CM
OS    rH O
EH    fe   .
               O O
                                        CM
                                    rH  
-------
 VO
          o  o
                            o o
          o  o
CM
rH
 I
                 00  03
                 O  O
00
                     00
                     o
•<*  CO
rH  O
U
CN
U
^

f_)
U


EH
rH
i-H
rH

(•"•
rH
PJ
Sc
rj
•

o
*

CM
rH
O
•


CM
CM
O
•


^*
CT>
rH
•

in rH r~
CM
O
•
rH
CO
rH
•


0"!
rH
rH
•



rH
•


CM
CM
O
*



vD
rH
•

VD m m o o
rH
•
CO
cr*
rH
•


^j<
o
•H
•

CM
rH
O
•


CM
CM
O
•


t^
CO
o
•

^rt ^^ ^rt
r-
CO
rH
•
0^
CM
CM
•


^*
O
rH
•

CM
iH
O
•


in
CO
0
•


O^
rH
rH
•

moo
CO
rH
•
i-H
CM
•


rH
rH
rH
•




1

CM
CM
O
•



0^
VD
rH
•

in o in o c
t-«
f^
CM
•



0"^
0
•



w
o



rH
o
t


CPi
VD
rH
•

D O in
1
CO
CPi
rH
•


rH
CO
0
•




1


en
o
o
•


in
rH
rH
•

O
o
r-
p—
CM
•


in
en
0
•

CM
rH
0
•



rH
0
t


VD
in
H
*

CM
CM
CM
CM
•



Cft
O
•

CM
rH
O
•



rH
0
•


0^
^*
iH
•

CO
in
CM
*
0

tl
CO
rH
fj
pr)
CM
U
CO






f>«
CO
O
•

1!

CO
1—1
CM
O
•HrrCciivv»r-
EHOOOOOOOOOOOOOOO
                                                        rHrHrH
   m
   CM
    C
    o
    4J
    CT>
    C
 (U  -H
 o  e  o
 (0  r-t  -H
•H  -H  f,
QJ  S  O
iH rH rH O rH
* *
CM CO
in VD
CM CM
X X
r- r-









*
CM



"TJ1
0
O
•
I
•H
CO
O

*
rH









J3
P-
P-
ct!
i/l
+-!
•H
I
                                               118
-------
fa
to
CM
rH ^*
| -rjt
fa rH
•
«-m
rH CM CM
CJ O O
CM • •
U
ro
rH
CJ ^l1
03 O
CM • 1
CJ
<*m CM
rH m in
CJ CM CM
O • •
j ^ ro in
CM rH VO ^J*
rH rH 0 O
rH • •

U -P 0)
m -in o •
rH f. flj 4J
04 9: 'W S
'•^ tJ» ^M


inro rom roin in ro •*
oOi-H rHoo r~co oo rnr-**
OrH rHO rHO O rHOrH
• • «f » » • •••
O
CM roin CM CMCMro
O OO O OOOOH
.|| . . | | 'III • • • • 1



m co oo »* co
ro o o o o
ill • i • i I i i i ii i > • •

r^^tcM r-cM^tr^ cMh-cr>cM mcM cMin CMCM
VO^*CM rs"rO^I'VO rHC^irOCM OrO rHO rHrH
CMCMCM CMCMCMCM roCMfMCM rocM roro roro
• •• • • • t •••• * • * t t *
HCOin HrHinrH rHHOOro rHOO VOrO COCM
inro'* inm^fin minro^t inro t*~oo oo
OOO OOOO OOOO OO OO rHrH
• •« «t«« ••<• «fl «• ••



VO vO vO vO vO vO
OOrHrH OO O OrH
OOOO OO 0 OO
. . . 'Ill • • 1 1 'I 1 • 'I

ro CM ro ro
000 0
OOO O
'II 1 • • 1 1 1 1 1 II '1 II
omm momm om oo mm oo mm
inrHO rHcoi-HCM <*CMrHO »*ro roro in-?}1
rHrHrH 1-HrHrHrH rHrHrHrH rHrH rHrH rHrH
• •• ••§• t**t •• •• «t

oooinoooininminininooooinininooooom
rHO'<3<^trHCMO'5j'inrHCMin^OCMinrO^I
-------
    CO
CN  ro
rH  rH
 I   rH
En   •
ro
rH
       in     in
       oo     oo
       o     o
                                                             in
                                                             oo
                                                             o
                                                                               in
                                                                               CO
                                                                               o
U
 CN
u
       rH  CTl
       rH  rH
                   I   I
                                o
                                CN
                                                  in  in
                                                  o  o
                                                                 I   I   I
                                                                       in
                                                                       o
     ro
     CN
    u
           CN rO
           O rH
                     CO
                         (N
                                    CO
                                    o
                                                                    oo
                                                                    o
                                                                 i   •  i
 TJ«    in  CN
rH     O  00
rj     ro  CN
o       •   •
                  CN  ro
                  rH  rO
                  ro  ro
              CN
              rH
              ro
                  CN
                  CN
                  CN
rH  O O
CN  CN CN
  •   •   •
                                                                r- r-  r- r^
                                                                r~   m r>
                                                                CN CN  CN CN
EH     f*  <*
rH     CN  ro
a
                  CN  CN
                  H  rH
                   t   •
                             00
                             O
                      ro
                      CO
                      O
                             rH in  in

                             o o  o
                              •   •   •
                                                                rH  CO  CN in
                                                                in  in  ro VD
                                                                o  o  o o
     ro
 Q>  rH     m
rH  M     CN
    in
rH  CN
O  O
                                0
                                O
                                                      o
                                                      o
                                                             o o
                                                             o o
                                                         o
                                                         o
•H     o  m
rH     f>  \O
    o m
    m r^
    rH rH
                                in
                  O
                  ro
                                                  in  m m
                                                  ^t  CN rH
                                                  rH  H rH
              O
              ro
                                                                        to
                                                                        o
                                                                       m
                                                                       CN
 fljommmoooooo


 E-lrHrHrHrHr-ICNCNCNCNCN
    (0
    Q
                                               ininoinotnoommo
                                               CN'tO'Jl'OCNOrH'^rOO
                                               OOrHCN^^tt^t^P^COOv
                                               OOOOOOOrHOOO
                                               CO
                                               rH
                                                                                      PH





                                                                                      0)

                                                                                      e/)
        0)
        o   c
        m  -H
       MH   (0
    QJ  Q)  4J
    U 4J   C
    (0 -H   D
                                                     120
-------
    cs

    r-l

     J

    fa
              o  o
                                        in
                                        oo
                                        o
                                                                        in
                                                                        00
                                                                        o
    r-f

    U
     (N

    o
       o  o
                          i    i
 i   i   i   I
   o
   t-*     CN
   o     o
I    •  I
     ro
    U
                                            III!
                                                          I   I
                                                                    o o
^*
rH
U
U
B
rH
rH
rH
O
CT»
(N
•
in
VO
O
•
O
CT>
CS
f
in
vO
O
t
(N
rH
ro
t
in
VO
o
•
(M
ro
r*4
t
ro
in
o
•
o
cr>
CN

__,
in
o
•
o

M
•
in
vO
0
fl
^J<
o
tN

H
in
o
•
cr>
CO

    u -P  fl>
    to -H  u
   H ^3  id
                                                                                  fa
                                                                                  CO
                                                                                          • H
                                                     121
-------
CM
H
 I     I   I
          in CM rn
      CMCMCMrHrH
                                  OOO
                                                              r- CM
                                             I   I   I
                                                                     en
                                                                            co
                •<* ro
       < CO P~  "3*  O H  CN  O
                O O O  f>  CM
                         I    I   I
                                   oooooooooooo
                                   oooooooooooo
                                    ........   t   ..   Jb
O
CM
t-l
F-l
1
CM CO
TJ in
o
in
o
CO
H
r-l
iH
in
CM
H
rH
iH
CO
VD
O
 CD
H
•8
                                                                            00
                OOO
                                   I   I    I
                                                        • o
                                                                 000
                                                                      CM
                                                                        •  O
     0)   oooooooinoinoomoinooooininin
                                                                                              CM
                                                                                              0)
     QJ   ^f n  O
     4J   H r*  CM
     a   \ en  X
     ^   CO iH  CO
                 CM
                        CM  CM
                                        \     \
                                                          o
                                                          iH
                                                               ro  vo
                                                                          O
                                                                          CM
                                                                                    to
                                                                                    4-1
                                                                                    •H
     0)
     o
C


I
a
                                                     122
-------
      eg
               «tf                 in in
               I-H  co  co         n M
         II    •    •   •  l   l    •   •   l
        III    •   l    I   l
                                                                                    I   I    I
                                                                 CO  CO VD
       •3<                               in ro     ro     r>     rH  r-H vo
      H                     in         r-»«3"(Minvovom
      U                     01         rH en     r-i     o     o  o o
      U    i    i   i    i   i    • o o   •   • o   •  i    •  o   •   •   •  i   o o  o   i
      u
              r—IO1     O  O O  O  rH r—lOrHr—)     OOOrMrHrHrHO'"!
              OO     OOOOOOOOO     OOOOOOOOO
            I    •   •   I	I	
04
 (U
iH

•s
     rxi r«j  H                   c^  r-
     CS M  M                O O  rH
      •   •   •  I  O O  O   •   •   *  O
    OJ            f^  VO                C3
    CM            vo  VD                m
    rH            O  O     O         O
     •IOO   •   • O   -OO    -O
      E
      •H
                                                                                                        PH
      0)
      4J
      m
      Q
                   in
                                 in
t
H
                                                   CO  rH
                                                   H  CN
                                                   \\
                                                   in  in
V

a

10
0)
O
            0)
            c
            c
           0)
                                                         123
-------
             vo

     CM      CO
     rH    I    •
                                                       rH  00 CM
                                                                         in CM  o co  CM o  vo
                  I   I    I       I   I    I   I   I   llT*COCMinCO^rHCMr-CMvT>00
                                                           COCMrHCMrHCMrHCMCMrH
           I   I
     O
                                             I   I
                                                    co vo  m
                                                                     rH

                                                                     CO H CM  rH
                                   o m in

                        CO  VO ^  VO I- rH
      CO
     rH
      CM

     U
                                                    in
                                                                                       m     m
                                                    t*~ oo  r^ co  r-     r~ r~  H
                                                     •   ••••      •••      t      t
                     I    I   I    I   I    I   I   I   I   rH 00  CO 'tf     OCOCOCMOHOrH
     rH


     8    •   •
                     I    I   I    I   I
                                      co co     in
                                      oo oo  co cr>  m
                                      CM CM  CO CM  -st
          in  co co  "tf CM  ^t     minin
       rj|<«j|CMCM^iin^|in\o^|cN
                                                    in            in CM  m            in     in
                                                    P-CMrHinCMVOr^rHCMVOr^inr^

           I   I   I   I    I   I    I   I    I   I   I   IrHCOCOOCM     rHCOCMrHCOCO
O
CM
(U
      CO
     u
           I   I   I   I    I   I    I   I    I   I   I   I
                    00  in     00 vO  00 CO
                                                    r- rH  co     r* r^  m
                                                    OrHCMrHrHrHVOCOCMCOOOr-

                                                                         ^* 0"!  r^     in oo  rH
          co
jQ   rH   in ^j  in in  CM o^  m o^  vo rH  in
to    co  ^d* o  m ^f  in in  *>}* rH  in CM  o rH     in  CM oo     m  c^     oo vo  cr* r^  ^*
EH   ffi   OOOOOOOOOrHCMCMCMt^vOcOOCMOrHOOOOO
     u	:	
     rH      CM
      I    CO O
                               co
                                         co  in CM  in vo
                                         rH  rH rH  VD O
              in     m
              rH  P~ VD  O
CO
in
m
CM
                    rH  rH
                                                           rH rH  rH
     Q)   oooooommooooomooooioooinoino
     £   rHinrHrHCO^'^'incOOCOOCOCOCOCOfOCO^'COCO^l'OrHCO
     •H   CMCMCO'*^^'^<#'*mmvDCOCftOiHCMCOr-»OOvTiOCMCO<3'
     EH   i—IrHi—I r-1  r-IrHrHrHrHrHrHrHOOrHrHrHrHOOOrHrHi—I  rH
     o)   m
     +J   CM
     (0   \
     Q   m
                                      o
                                      co

                                      m
co

oo
                                                                         oo
                    0)

                    03


                    w
                    .(->
                    •H
                    C
      0)
          c
          c
      y   o
      as   >i
      -i   ro
      Q*   CQ
                                                  124
-------
CN    O  O O  O  VD
!—!••«••                                                                             *3*  CJV  CJ*  rH  O V£>  r*~
 i     r-  r- co  cri  01    111111     111111     111111      	
trHrHCNHrH                                                                             rHrHCNrHi-l

  *tf
rH        CN         cNinrHrHrorH           t~-  r~      r~   r-      r-
O    in  co I-H  i-H    CTI  co  o to    mmcNCNCNCN   cNincNom       O'S'incN^rocN
  CN   •	         .......
UrHrHi-HrH        rH         HrH                      H                   1-HOi-HrHrHi-ICNrHrH
U
ffi
                          r~-r~r-~     r^m
                          CNrHrHinHr^
                                                                                               IT)
                                                                           
(0
Q


O
(0
H
(i
OOOOO CN a>o votnoooLO^ rocMrvrsjiHro ^rrvjrococNfN co^roco^oin^
^T 00 rH iH

ooooo oooooo LOOLOLOOO oooooo 10101-0101/^1010
OroOOO iHO^OOO CNmc^ronro OO^OOroO i-Hr-lr-irHiHiHrH
o rH c^j ro ^j1 CN ro ro ^ LD vo CN ^ LT> v^ r^- co o rH i — i CN CN co CN ft ^ to vc r** oo
rHrHrHiHrH rHrHrHi-ii-HrH rHrHiHi-HiHrH rHrHrHiHrHrH rHrHrHi-HrHrHrH

^ CTl rH LO
^yg CN LO T-H CN
"S^ N^ \^ X^ X^
00 00 c7^ CJ> CTi
Q)
C
0
t>i
ft)
CQ












^3
a,
£X
CD
rH
rt
V)
H-»
•H

3






                                                            125
-------
                                                                               in
vDOrH    cn  VD CN i>  O "31   ro ro  vO r~ r~  O    O  T ro  ro  en vo   rH rH  rH rH  CM












(A
CN
H
0)
, — |

rt
EH



















i
fa
rH
U
CN
ro
U
CN
u


u
u

EH
rH
H
ro
rH
u
5

ro
rH
fa
rH
CO

rH
rH
fa
0)
g
-H
^

Q)
4J
m
Q



rH CN
\^ "X^
rH rH
rH rH





0
CM
ro
ro
vD
ro

CO
vO
ro
rH

^r
rH

^
ro
rH

O
•31
CM
•=r
VD
CM

cn
vo
o
o
CM
rH









CM
ro
00
ro
rH

CM
VD
rH
CO

VD

VD
vO
CN

CM
oo
ro

CO
ro
VO
r^
co
o
o
ro
H









cn CM
CN
rH CO
CN "31
CO
O H

O CO
CO O
rH rH
<*
vO VO
m VD

VD
VD CM
rH

o r~
CM VD
rH rH
00
vO O
rH CM

VO rH
VO [^
0 0
0 0
*r in
rH rH









rH CN rH
Ln VO VD H VD
vominminin cno^u-j^o
in in
CN ^ rH
oo o'ooo'oo
ro in ro r~ ro
covO^rocoo rfrocNroro
^1* rH

cMunco co cMinr^cMCO
'^'S'rOCNinr^ •xfCMrHCNCM
rH
CO CO ro ro
vD VD CM in CM cn CN
HrHOOOCN rHCNO O
o
ro r^ ro
oommoco cNOvomro
CN'3'CNrH'^''31 CNrHrHCM

LO ro ro c~~ r>- in in
^y rH ^T ro CO ro ro ^ CM CM ^
rH rH
in in m CM r* ro
t^OOTCOCO CMOvD'tfCO
CMVD
^-J
•H
a





                                   126
-------


C
•H

CO
C
o
•H
cd
O
O


CO
3
O
•H

to
s)
4J ^N

a,
CD CX
rH ^
 CD
0) C
i-l O
•H
r* 4J
0 cfl
V^ i *
u cu
O 0
rH C
cfl O
s u
e
3 •
•H 0)
CiJ
*^
•rH fl)
S 4-1
^
r* *rt
n) QJ
4J
6 -i-i
3 C
St— j
i—1
•H i
'X CO
S H
•
"*3«
CO
1 — 1


a)
rH
*^
crt
»y
H
U
U
H in
U CO 0
CJ CN O

CM
U
O CO O
CM CO i-H
U O O
O


^r ID CM
I-H ro rH
U 0 0

ro
rH
rj rr
u o •&
ro CN O
CJ 0 0
CM
fa
CN co in
H ro CM
U 0 0


fa
ro in CM
H in H
U 00
to
H
cu
> X C
0) Id -H
nJ 2 2

CU
to
id
ffl

*O
^
• id
• o
c w 'id
O to C
•H -H 0

rd y 4J
" m *
0 <" S
fj CO ^

r>
cr* *\
G cn
•H rH
^ \^
O 'O VO
•P O 1
•rl -H 00
C to H
0 
CM
o




rH
vO
o



in
H



*>J*
•sr
H

S
0)
2

























O
co
o




<*
rH



VD
VD
O




ro
ro
O



CM
ro



in
r-
0

S
2




•
*"D
•
x
*.
8
K
^1
1
co


«^j*
r-
\^
in
*^^
r>
i
CM
\

m
o
0
V


in
H
0


m
CO
o
o




ro
o
o



•^
0



0
H
o

C!
•H
2






^^
o
0
o
s
K
4-1
o












<*
ro
0



en
ro
o



CN
CN
0




m
H
o



CN
H



CO
CM
0

§
0)
2

























vD
m
0



H
in
o



^ji
rH
0




0
ro
O



ro
H



rH
CN
o

s
2


H
CU
Q

•»
4-1
•rl
U
CU
S
s
id
rH

^
p^
\
O
i-H
\^
r>
1
CO
*\
f-
m
o
o
V


CM
0
O
V


^Q
o
0




ro
0
O



<*
0


in
en
O
o

C
•rl
2

CN
t~*
0)
4J
^3
O

c3
00
•*
•O
id
0












m
ro
o



^1
CN
o



en
o
o




o
r-H
o


CO
VD
0



ro
H
0

§
cu
2







"5"
0
•H
4J
O
0)
to
in
a)
4J
C
•rl












in
o
o
V


0^
CM
O



VO
H
O




r-H
CM
O



00
o



CO

o

X
id
2






•
TD

CU
to
O
-H
4-J
i-H
id
CQ

r-
x^
CM
rH
\^
f"-.
1
i-H
r-H
^\
^
m
o
0
V


CN
O
O
V


VD
0
O



<^1
^
o
o


in
CM
o



o
rH
0

G
•H
2
^
to
tn
ra
PH

rrt
iH
•H
id
U
§

rH
O
rH













1




CO
i-H
O



CN
r-H
O




CN
H
O


O
•ST
O



^
CN
0

(U
2


Id
cu
to
a

•O
to
•rl
•a
i-H
O
03

•s
O
fa












ro
vD
0



cn

O




ro
O




m
ro
O


CO
i-H
o



CO
ro
o

X
rd
2




0
•rl
C*.
0
*.
C
0
4-1
C
•rl
rl
••H
S

?
\

CN
\^
p^
1

rH
*\
^
m
o
0
V


CM
O
O
V

VO
CTi
O
0




ro
0
O


CO
O
O


CO
r~
o
o

.5
2





>i
4-1
§
O
U
c
s
c
rH
CJ












en
rH
o



in
rH
O



0
CN
0



r>

0
o


rH
H
o



^
H
O

§
0)
2





^-+.
Q)
CO
id
CQ
cu
o
to
0
fa
•rl












in
ro
o



en
rH
o



ro
ro
O




ro
r-H
O


r^.
r-H
O



00
H
0

X
id
2


•S
id
4->
n
3
1

01
o
id
fa
0)


S
"X^
en
H
\.
en
i

M
\
cn
in
o
o
V


CN
0
O
\f


0
CM
O



CN
ro
O
O

m
CO
0
o



o
rH
0

•H
2






CU
4-1
rd

*
H
O
X
cu
z












0
rH
0



t>
0
O



VD
CM
0



f-*
VD
0
0


O
i-H
O



ro
H
0

§
CU
2


























CO
CO




CN
00





00










CO
00

X
id
2







^
*
Z
cu
C
c
o
id
CQ


ro
r>
^s.
CM
H
1
ro
p>.
N^
ro
in CN
o cn
0 0
V


O ro
ro vO
O H



m ro
O vD
0 H



in
t — cn
o m
O rH

0

O CN
O VD


VD
^ ^
O ro
O H

c
C TO
•rH CU
2 2

























127
-------
ci
•H
en
0
o
•H
4-1
O
o
CO
3
o
•H
J^
cfl

4-1 /-v
Q.
en ft.
I s^^
CU
> W

O CO
rO IH
M 4-f
rrt f"1
CU C
CJ CU
0 0
rH G
Cfl 0
fTj t_)
0
0 03
•H CU
C3 4-i
•H Cd
r5-4 •J-'

C/j
*"O
S *^3
cfl CU
4J

0 %r^
3 fi
e P
•H
X  3

r-H
•* id
4-> fi
•H 0
tn 4->
rd rd
O 2
co — •

^f
o
x^
en
rH
\N
VD
1
00
•-H
^s^
^o
in m
CN rH CN
o o o
o o o
00 rH li)
•*r o I-H
o o o
V
0 0
H rH I
V V-

m I-H m
0 0 O
o o o
o o o
V


CN ro
ro o rH
o o o
O O 0




X C n)
cd -iH CD
s s s




f~^
C
o
4->
• Dl

• -iH
^ X
' s
^
M oa
o
4-)
£ m
O *3*
IZ «-

^J.
t~-
\^
co
CN
^\
vD
1
r~
CN
^N^
ii)
VO rH CO
in o o
0 O 0
V
ro
iD iH ro
o o o
o o o
V
o o
rH rH 1
\s v

CN rH in
H O O
O 0 0
o o o
V


ro
VO O ^
rH O O
O 0 O




C
cd -
H
0
O 1
V
rH
o
O 1
o
o en
rH f-
V

rH ^3*
0 O
0 0
0 0
V


CN
O rH
0 O
0 O




C ro
a s


CN
t-~

CI)
+J
3
o
Pn -*-~*
C
c8 O
•rH
CO 4->
*T O
^ CU
CO
•O >H
CO 0)
O -P
pi c4
"— -rH













CO
ro rH ro
o o o
000
V
rH r-H
o o
o' d i
V V
m
O 0 CO*
^ rH ro
V

CN i-H r>
rH O O
O 0 O
0 0 O
V


ro rH CO
rH O O
o o o
o o o
V



Cd -rt CU
a s s


U)
CO —
rd rd
en eu

'O id
• M
•O -H n3

to -H
» 0 XI
cu S cd
M O rH
O C4 O
6 ffi
•H H
•POT!
rH 1^ M
Cd rH O
CQ ~-^ CM

•*
r-.
^\
CN
rH
N*^
f"».
1
r-H
rH
N^
r~
in
t~ rH
O 0
0 0
V
H
CO O
^ o
V
^ K*
*2! fZ


rH rH
O 0
0 0
O 0
s/ V


VO rH
rH 0
0 0
0 0
V



cd -H
s s






0
"*l ^1
A -P
O C
3
•• o

4-> C
rji O
C -P
•H C
e -H
rH rH
•H U


^J,
r--
X

CN
X

1
^D
rH
^s^
r~
li)
rH
o
o
ro
o

1




1



r-
o
o
o




id
1







*— »
Q)
ca
us
CQ
0)
o
iH
o
CM
J^l
•H
-------
of Halocarbon
to &
H ^
 0
0) rH
J rt

•H £
ro .H
u c
•rH 3
a
>i
EH


*
*
«*
rH

_i
O
JH

*
a
r-
X 0
P» O
CM CO
X CM
VO
CT>
0
O
•tf
CN
•
O
no
00
o
t
o
rH
rH
•
o
ro
rH
•
O



(U
-p
(0
.p
CO

t
r*
t
z


•
to
c
•H
n>
•4J
c
D
a_

Q) 'c'
u m
(it ,Q
b S-i
3
0) t
4J C

^5
£
X 0
P* O
rH CM
X rH
cn
ro
O
00
CM
0
CO
•H
0
CM
•
O








•
r^
•
53

*
\A
0
o
as

^i •*•*
ro o
rj J^|
m o
CO
*
Cm
*r^
(0  O
X O
CM Tt
X rH
f*»
CM
O
cn
rH
O
CM
O
O
CM
O
00
rH
•
O






'O

(0

o

rH
a
G
0
•H
.p
fd
^

i

b

^?i

*
•P
M
•H .— •
Cn CD
m to
0) (0
en ffl
£
X 0
O\ o
X rH
r^
CM
0
•
o
V
0
rH
•
O
in
CM
o
t
o
o
r-
o
o
CM
rH
t
O







•o
(U
4J
m o
> •*
0) ,C
H 0
(U

^ c
G 0
0 -P
•rl C"
to C
JH -H
0) e
> rH
C -rl
H £

Q) x-.

4J J
m
0)
> 0

rtl in
?
X 00
Is- CM
X rH
r^
ro
r-
•
o
rH
t
CM
in
V0
o
*
o
in
cn
o
o
•
00










C 0
O -H
•H A
V O
fl)
> »
0) C
rH O
fl) jj
^ cn
c
rl -H
o e
I*rH
10 -rH
J &

fl ^^
o •
-rl -P
tQ «*H
M
 o
C m
H rH
r-

r- o
rH CM
XrH

129
-------













to
G
|

ro
u
0
rH
(0
w

MH
O
CO QJ
rH PH
cu
>G)
£_J
(^
I/)
to •£
O .s
•H
a
>S|
EH


•
A
^*
rH

! *-*
o i ra
'D
CHJ
^"^
rO MH
W O

% •
C -H
(0 E
0)
U ro
0 ~

rl •
 m

•H -a
tT1 M
(C (0
0) D
tn o
-*
r^ o
X 0
0^ CO
r-l rH
X
r~

CO
rH
•
0

rH
0
0
v

g


rH
O
O
f
O
V

rH
O
o
•
O
V


CN
O
•
O
V
•c
a

(0 O
> -H
0) ,C
rH O
Q)
•— * ^
C
C 0
O 4J

to c
t 1 ,pj
CU £
> rH
C -H
H 5

Q) ^^
rC '
[ 1 | i
MH
(U
> 0
0 0
rO O
•<*
r*- oo
X CN
r** CN
rH rH
X



CN
•
CN

CN
rH
O


^


rH
O
O
•
O
V

rH
O
0
•
o
V

lO
r-
o
•
0




o
TJ -rl
Q) 4^
4J O
ro
^ ^
0) C
rH O
Q) 4J
-^ tr>
c
M -H
d) £
?*1 fH
(0 -rl
h3 S

C ^»
O •
•rl 4J
cn M-I
>_l
0) O
> 0
C *ft
H rH
^
r^* ro
X 0
r- CN
rH rH
X
r*
130
-------
                      <#>
m
•a
              •a
 W  g   (0

 O  o*   >
•rl       Q)
jj  to    -
Tj  i)
 (O  *^
 U  -H

rH  3   U
         Q)
T)   W  +J
     §0)   (U
     3  "O
    rH



J   fiS
•p   (d   d
     0)  -H
 was

 O  'O
-H   O
 H  -H  .p
 fd   M   fO
 >   (I)
    CLi   CO
•P       C
 ca   tn  o
     fl  -H
 03  -H  4J
H   rl   (0
     O   >
    •P
    •rl
     C
     O  J3
•P  S   O
 C
 Q)  T5  >*H
•H   G   o
,D   a]
 B       SH
 (3   C   
                          to
               H
                I
                          W
                          EH
t£> «a*
CN  in
--- rH
o en
rH 0
in o
r- o
rH
CN ID
rr ro
0 O


o m
r~
CM in

CNJ CM
oo en
rH rH
X. \
IS V0
O t£l IQ
^r co CN
rH CN ro
CN rH *-*
o m CN
rH 10 ^
O ^ O
in CM
rH
r- in H
<* r-
O rH rH
O
rH
m
CM
o
rH O O
r- oo o
i-H
r-» o -tf
•^ rH •-'
r- •"
O rH i-H
O O O
O ID rH
•sr oo <*
rH H CO
CN rH —
in r- o
CN  l£>
cr> o m in o
r- •* ro CN m
m oo ro ro 
\D CM CN rH O
en o o in o
rH CN t~
rH
* S Ci^i
~^ in 10
\D CN CN «* rH
H O O O O
O O O O O
l£ CTi
rH
I-H in I-H co n
in in
CN CN CM
O rH O rH O
O M rH O CO
or* ro r— o CM
H
•si* r~ o o i£
^j *— "^ 1 _J V,^*
i-H VD r« CM m
o o o o o
co * rH O H
0 O 0 0
^ ro r^ >£>
m CN CM
CN ty in «tf
n >_»_->_
oo ro in
CM rH i-H rH
in
1 O
CM CO Cn rH
\ \\ \
r~ r^ r-- r~
o en ro
r- CM «*
•^ ^oo
•*~>
o r~ ^
rH OH



0
ro
CN
ro
O
O 0 CO
•* ro
O i-H CO
t ^^ %•„«•
*" CN CO
rH 0 O
O 0 O
co o cn
CM in r~
ro ^ m
c*1 CO CO
rH rH CN
o
rH
1 rH (M
00 rH H
\ \ \
r- r~- r-
m
CM
CM
rH
CN
rH



o
ro
CM
ro
o
CO
ro
cn
00
o
o
m
r~
o
rH
•f
CN
CM
rH
rH
rH
\
r^
                          8
                           •rl
                            rl

                            S1
                            Q)
                           to
                                                 u
                                                                 to
                                                                      o
                                                                      o
                                                                                         •H  0)
                                                                                         S  Q
                                                                                                       m  s
                                                                    131
-------
CD
M
 0)

•H

 O
rH
A
U
 >t  W
 C  g
•H
                 Q

                 cn
vO
       Q

       w
    *°


  ^
H
U

U  rtj
       W
       w
DC
  f>
U
U
CJ
    Q





rH
CM
(N
ro

T ro
v£> in
Cn
ro ro

0 rH
•sr in
m 
-------
o
    o
    r<
-Q  .H

 tfl  C

H  3
                 W
                 g
             ro
             HIS



             O X
              i  w
                EH
                rt!
                Q
O O Cn
rH

H rH CM
rH IT)
•^ VO r-{
O O oo
o
CM
rH
ro
O
O O O
m
rH rH CM
in
CM CM CM
o o o
0 0
r7
in
o
o
O O v£>
(N
i-H rH CM
H CM rH
H 1-1 ro
VO r~ 00
H rH i-H
\ \ \
r> r- r-
o o
rH CM

in rH
x— •* i-H
in m
0 0
en
o
rH
vo
rH
in
ro o
on
rH
ro vo
cn
ro o
0 O



03 CO
VD i-H
•-* rH
CM ro
H H
i-H CM
CM CM
\ \
r~ t—
LD o
r- ^

oo o
•-' rH
CM in
i-H i-H
r-~ ^i1
cn &
rH
^ VO
•tf
rH
CM O
rH
O O
vo ro
VD O
rH CM
0 0
o o
P CM
•31
H 0
0 O
Cn rH
rH CM
00 rH
S—' 1
VO <*
rH H
ro 'tf
CM CM
\ \
1s* r-
0 0
i-H

00 rH
Ch
rH O
CM O
>£
rH
in rH
VC CM
CM rH
O O
O O
•-
p^
•^
r~
(Tl
0
r~-
CTi
CM
«tf
•*
ro
rH
00
CO
m
vD
rH
O
rH
r-
&
r^
o
o
VD
'T
CTi
^T
'S1
rH
VO
CM
VO
rH
\
r^
O 0
m f

CTl rH
m
-31 OO
0 O
o r-
m k£>
VD 
>£ en
O 0
o o



O 0
In r7
ro ro
o o
O 0
CM ^<
rH rH
cn vi>
-- rH
CM •*
rH H
vo r~
rH rH
\ \
cn cn
O 00
-sT rH

rH ^~'
cn ro

VD
O
O






r~ CM
i-H
Ttf TJ
rH ^
CM ro
H rH
oo cn
rH rH
\\
cn cn
cn
ro

T
r^
kD
O
CO
r-
,_4
CM
cn
o
o



in
H
to
ro
O
O
"31
i-H
ro
<*
ro
rH
cn
r-H
1
VO
H
cn









o
CM
H
^^
<£>
CM
rH
in
00
r^
*«*
CO
CM
m
r-
\
ro









VO vO
in •<*
H rH
"* O
i-H CO
VO
O 'tf
O O
•^r CM
r~ vo
rH
O 00
rH rH
rH rH
rH CM
a ro
r- r^
\ \
•* m
cn <*
CM CM
H

CM ^
CO H

\ \
00 cn
CN o in
^r oo
rH

— ' rH ---
r^ r^ r~
ro P^ CM
CM
moo
CM in o
H H
in co in
"* o cn
H ^ O
O ^ rH
o o in
rH rH
~- rH •—
rH oo in
CM CM in
vo ro in
r^ CM
in co in
— rH >-'
in oo in
T CM CO
rH
r- vo cn
in <* vo
in oo in
•~- rH -^
in in ro
rH CTl VD
rH ^J< CM
n co oo
r~ r^ r~-
\ \ \
O rH CM
                3      3
                                                                   0)

                                                                  -P  Q)
                                                                  -H  O
0)
a
c
o
                                                                                         m
-------





Q ^
m D
rH H
rt
QJ
. (/)
^Q < i
cO c
H O



Q
eW •
CN
rH
1
a
Q
T
U
U
§
•
Q
* •
ro
O
CN
O
Q
Cfi
U
PLACE DATE !•
o vo o H r> CN r> o o o r- •^rococorHcocn^1
rovD ro CN-sf CN ^forororocNcnro
rH
rH ro rH T vo in rocNrorHcn i^cor^cocNincnin
in in
VD cncoHcn H I-HOCOCOO vovocn r~ ro
rH OOrHO rH rHrHOOH i-HCNCNCnroro^frH
CO rH CN VO
rH rH
^< ororooom vomt^OiH 'jin^'coo
ro in^inro cn inr^Hot^ cot^rocoro
rH
CN romcnvDrHvo movovoro •^coinr^in
in
VD vO'd't^ m cNoovD'^'r~ voocncoro
in OHrHHrHH OOOOO rOCOOvDvO
CN CN rH
o ovor-o oo ^inoror- voocnr-o
cnin ro ^r~ roco CNVOCNIH
H rH rH
CN rHinr^H vo rocnrHcNin vor-incNH
[^
VD CN^^OO Cn vOCOCOvDO vDrOCN in
rH incNrHO H HOOOH vDinenvOrH
rH
oocororomrH^roo co^mr^o inovoro^o^o
^TrHrorO'd'pH f rOrHiHrHCN r~incnCOCO'3'roro
rH
rHrHcNinrHcoi— icorHoo cnvDvo^fin vD^cNrrcnincQin
^^ »-» • — v rH — 'rH1 — — '^ ^^ i— 1 rH — * ^" •— *^ H CN rH ' — rH — '
vO
rHCyirOiniHrOCNCNrOO rHCnvD^VD COVD^CNOrHvDCN
rHOCNrHCNCNCNCNCNCN CNCNCNCNCN rOOrH'3l'!3lrOVOrO
vD en
CN rH
1 1
vor^COrHcNrO'S'invOvO vOt~-COcnvO rorororororororo
rHrHrHCNCNCNCNCNCNrH rHrHHrHrH t>r-l>r~r~r-r--r--
r^* r^ r>* r*~ r^ r*^ r^- r^~ r^- r^- cn cn cn en cn ro *vf in co en o rH CN
rH rH rH
-P 0)
1 g C
0) C
gO -4-1 0) O
H -H -HO >i
•H A X! ffl tO
so s &< m
134
-------
Q)
•a
•H
rH JH
>i 0
C H
> O
0)  H OH
0) 1 CO
Q fa
en
fd •<*
S H
O 0 O
tt CN O O
fi U H H
3
O ro
S U
O 33 r- o
U CN v£> O
U H
U
rd
H O 0
A U 00
O U H H
•H
A
EH
C H O O
•H H 0 O
rH H rH
cn
Q)
in ro
•H O ro ro
id K ro ro
O ro
H O O
tn H
(U ft.
rd
fi H
 o
ro i£> o
rH
O O O
0 00
rH H H

CTi
rH
1
oo t^ oo
H CN CN
O O O O O
H O ro iD ro
H CN ro ro
CN ro H CO O
CN ro CN CN
cn o ro in r--
CO O ^O CO H
H
in o *3* H o
cn in ^ ro
in o o o o
(T> O O O O
H H rH H
cn o o o o
CO O O O O
rH H rH H
CN in ro co r-
ro CN H H
in ro vo CM o
ID \Q m

rr co co CN o
r~- oo co c^ o
H
o o o o o
0 0000
H H H H H

00
CN
CN CN ro <* in
o o o o
m
^ o r^ o
CN in m m
^f o o t^
CN m <* H
in o r~ in
p- in vo CN
co m o o
ro CN in
o o o o
o o o o
H H H H
O O O O
O O O O
rH H rH H
CO O O O
H
ro O O O
"
ro o o in
cy> o in r-~
H
o o o o
O 0 O 0
rH H H H

in
1 O
CN CO O> H
r-- r~ r-- r~
r~ o o
H m
ro O ro
m o 
in in o
ro r~ m
o in m
in i~» t~-
cn o o
CN
o o o
o o o
rH H H
o o o
o o o
rH H rH
O 0 O
O 00
m

rH in O
r- CNO
H
o o o
0 00
rH H H

o
H
1 rH CN
CO H H
r~ r^ r-
H
in
r-
CO
m
m
r-
0
o
o
H
o
o
rH
O
H

in
o
0
H

CN
H
1
H
H
r--
4J
•H
i
O CP • H3 ,* g • -P
fdrd SH CO HH H.
H(U > rdO -HO) rdTj
04U] S W33 SQ «S
13.
-------

























M
vO
i — 1

(U
rH
rt
E-<




















10
to
rH
|
PM

<3-
, 1
1^
U
CN
u
ro
i— l
O

(N
O
•^
rH
U
EH
H
rH
rH
ro
rH
u
g

ro
H
H
fo

rH

B"
rH
rH
{
&,




w
EH
rtj
Q



W
<
^
p,

O O O O O O O

o
in o o co ro rr in
ro ro ^ p*


oooor^rocNino
O CN VO CO f^ O
H rH


OOOOCnrooroo
O VQ IO rH
rH

OOOroOOOOO
OOOCOOOOOO
i~H i™H ^H i~H i~H P* t pH rH
OOOroOOOOO
OOOCOOOOOO
i-HrHH rHi-HrHrHrH

oooomoinino
o m in m i^ o
i-H iH


oooommrHOO
oooinmr~cnoo
rH i-H rH H rH


OOOOOrocoroO
O in rH rH rH
rH
OOOOOOOOO
ooooooooo
rHi-Hi-Hi-HrHrHrHi-HrH




*>Q f^~ CO ' — 1 CN ro *3* in vO
i-HrHi-HrNCNr\lCNC\)CN
\. "^X *\ ^^ \. \» \v \v ^^
[^-r^t^r^-i^r^-i^t^r^



• *
e o
rl -H
•H Jlj
s o

0


01



CN




CM
ro


00
en

00
en


^
in


CO
p^,



CM
rH
O
O
rH

VD
CN
N^
VO
H
\^
[^.











O
O
i-H

<£>
in



ro
ro


O
O

O
O
rH

(^
U


O




vO
m
o
o
rH




UD
rH
*\
en

-K
*
i)
-P
•H
r]
^

O


O 00 O
O ro O
i-H rH

ro CO O
vO ro in



vO O) O
in m


0 0 O
0 O 0

0 0 O
o o o
•H rH H

VO CO O
in ro


o o o




v£> O O

O O O
O O 0
rH rH rH




[^ co en
rH i-H H
\^ ^x ^^
en en en

B
4J
^
CJ
U
OJ


0


en
r-


rH
in



ro
ro


O
0

o
o
H

CO
ro


O




ro
rH
O
O
1-1

en
rH
1
ID
H
*x^
en











o o o
o o o
i-H rH H

1 1 1




1 1 1



O ro ro
O ro \o
rH

i i i


i i i



i i i




000
000
rH rH rH
r^ r- o
in VD VD





ro ro ro
r~ r~- i^
\x *\ "s^
ro «3* in



fi
O

(0
CO



0 0 O
0 O 0
rH i-H rH

o in o
o en o
rH 1-H


i^ en o
ID CO O
H

O O 0
o o o
J 1 1
^1 r~1 n™1
O CN O
0*3*0
rH rH

en co o
r- m O
rH


m i o
m o
rH


\o o o
en o o
rH H
0 0 O
0 0 O
rH rH rH




ro ro ro
p*" r*" ^^
s\ x^ %^
oo en o
rH










0 O
0 O
rH rH

0 O
0 O
rH rH


r~ o
IO CN


0 O
0 0
i"H i"H
O 0
0 0
i-H rH

^ o
en o
rH


0 O
0 0
rH rH


0 0
O O
rH I-H
0 0
0 0
l-H rH




ro ro
t*~ I —
x^ x^
rH CN
rH rH

































































































O 0

II II

0) Q)
•a -a
•H -H
H M
o o
rH rH
6 U

rH i— (
c c
•H -H
^* ^
*
* *
136
-------
analyses where detectable levels were observed.

In Table 17 an attempt has been made to quantify the degree of variation
of the ambient levels of the eleven compounds measured.   For each com-
pound, a "weighted average standard deviation" has been calculated, by
summing all the individual location standard deviations with weighting
factors proportional to the number of measurements taken at each
location.  The resulting values are listed in order of increasing
"variability."

This data is presented graphically in Figures 31 to 77 to demonstrate
more clearly diurnal trends.  Table 18 lists aerometric parameters for
all times and locations monitored.  For purposes of later discussion,
some representative atmospheric measurements taken at four of the moni-
toring locations are graphed together in Figures 78 - 81.  The key to
symbols and scale factors used in Figures 31 - 81 is given in Table 19.

6.2  Discussion

Because of the need for a halocarbon data base, initial studies were
concerned with characterizing the spatial and temporal halocarbon
distributions.  At all locations and times indicated in Table 13, CClsF,
CC12F2, CH3-CC13 and CC14 were always easily measurable.  Accordingly,
they have been classified as "ubiquitous" for discussion.  The minimum
detectable concentrations for the analytical methods used to measure
the non-ubiquitous compounds studied are given in Tables 13 and 14.

6.2.1  "Ubiquitous" Halocarbons -

The minimum concentrations that have been observed for the ubiquitous
halocarbons, CC13F, CC12F2, CH3CCl3 and CCl^, since June 1973 at the
time and locations indicated in Table 13 are 0.046, 0.06, .03 and 0.05
respectively.  It is interesting that the values for CClsF and CC14 are
comparable to the reported background concentrations for the two, of
0.05 and 0.06 ppb respectively(I0>13).  The minimum CC12F2 concentration
of 0.06 is an order of magnitude less than the concentration used by Su
and Goldberg(lS) to calculate a 30 year residence time for CC12F2-  Their
background CC12F2 concentration of 0.7 ppb is inconsistent with cumulative
world production data.  The integrated worldwide CC12F2 production would
give an average background concentration of less than 0.1 ppb.

During extended periods of inversion the ambient concentrations of the
ubiquitous halocarbons may attain values as high as 100-500 times their
minimum concentrations.  For example, the maximum concentrations ob-
served for CCl^lr, CC12F2, CH^CCl^  and CC14 during a three day inversion
in Bayonne, N.J. were 8.8, 47.0, 9.8 and 18.0 respectively (Table 13).
                                    137
-------
Table 17.  Halocarbons and SF6 in Order of Ambient
           Variability - Expressed as Weighted
           Average S.D. for Each Compound*.
          CC14                           50.6

          F-12                           50.7

          F-ll                           59.6

          SF6                            66.1

          HIT                           66.5

          C2C14                          68.7

          F113                           95.4

          CH31                           96.5

          C2HC13                        112

          CHC13                         129
   Vinyl chloride:  Insufficient data

   *Calculated as        .Z. S.D. x No. of determinations
                            No. of determinations
                          138
-------
            (U
 ra
 C
 o
•M
4J
 (0
 u

3
-H  I
 3
 U
•H  t
 (0
04
                       in
    VD
CO  tt
o  co
                                                                               00 CN
                                                                                      co
 en
            O
            O
           oooooooooooooooo
                                                                ooooooooo
 CO
 3
 o
•H
            O
            !23
           OOiHOi-HOOOOOOOOOOO
                                                                OOOincoroocoro
 (0

 0)
 H
 (U
-P
 (U

 (0
 s-i
 ro
O4

 u
•H
o  a-
a  a
           ^5  ro  10  CN (""••  ^o  f**  ^^ ^3  m  oo CM CM  CM  vo o^      (^
O'CL     OCO^^DOrorOrtfOroOOOOCOCTiOOOO      O
    Oi     CMrHHrHrHrHrHiHrHrH                            rH
 O
 M
 0)
 1
•H
EH
oomoominininooooooo
 0)
            0)
            -p
                       00 •<*
                                                                           X  
                                                                           VO  rH
            0)
            u
            (0
           rH
            Oi
            +J
            5-1
            -rH
            Cn
            (0
            0)
                                                        139
-------
 tfl
 c
 o
•H
4J
 (0
 O
 o
•H

f
 U
 (0
           in     or^omcN^j'invDC^ivDo
                rHCOr-ioa>r~oo
                  iH     r-t  rH iH  i-l     i-l
•o
 c
•H
           OCL     ooooooooooooo
           u  Q^
 03
 3
 O
 (0
           oa-     ooooooooooooo
           25  O-'
 03
 j-i
 0)
4J
 QJ

 (0
 Vj
 rC
 U
•H
 S-l
               Qi
 O
 U
 0)
 0)

•H
                      omooooooooooo
n
oo
r-l

(U
!-|

•8
 QJ
4J
            a;
            u
            (0
           r-J
           04
           -P
           S-l
           •H
           Cn
           (0
           (U
           CO
                                                        140
-------
 M
 c
 o
•H
-P
 ro
 u
            en
              V0
tn  ^
vo  00
•D
to
CD
e
•H
CO
D
O
•H
M
4J
oO'HcMoo'd'invovDr*-c'^Or-Hi— ICM
H rHHHrMrHr-lrHrHrHrH-ICMCMCMCM

G) r** ^*
-P CM r-
10 \ O\
Q VO r-l
^
4J
-H
O
o
QJ >i
U
ns S
r-l Q)
04 J5

CM U3 in
r-t r-l rH



o o o
o m in
CM CM t^


o in o
o r>- o







o o o





o m in
rH CO CM
oo  o
•H

00 ^
CM r^
•\ en
VD rH










                                                            141
-------
          0)
 w
 c
 o
•H
-P
 m
 u
rH I
 3 £
 u
•H cn
      o CD in
      CO vo VQ
•a
 c
 Cfl


 I
•H
O
U
8
a
a
                   oo m o
 U5
 D
 0
•H
 M
 (TJ
o  a
53  a
      o o o
      o m m
      M ro ro
•P
m
 VI
 0)
-P
 a

 (0
 X.Q
§§:
      o o m
      in in r-
      ro rf ro
 u
•H
 VI
-P
 0)
 £
 o
 M
 0)
             a
             a
 0)


•rH
                   O O  o
      o in in
      in o •<*
      o rvi CM
      rH rH .H
a
oo
 cu
          (U
          -P
          (0
          CD
             cn
                   •H

                   O
          cu
          u
          ra
          rH
          O<
          Q}
                                                 142
-------
 co
 c
 o
•H
-u
 (0
 u
 o
            0)
           -P
           u £
           -H
           4J  01
                      in
                                                             n  in o  
                                                             in  vo co  cr>
•a

 (0
     r-  co
              ,Q       •    •
           OO-    CNCvJOfMOOCNOOOOOCMOOO
                                                                               OOrHOCNHOJOOr-r-fN)
                                                                                                                   rH
(0

CQ
M
Q)
^J

i
(0
M
fO
               a
                         r*  CP> r-
                                        co
                                                                               HHCN
                                                                               t^r~-vovDro
4J
(U
E
o
M
0)
           irorO'*vor^ooOrHrv)ro
-------
 en
 C
 o
•H
•P
 OS
 o
            0)
           -p  — *
iH  I
 3  S
 u
•H  Iji
-P  a
 M  *•— '
 (0
                                         in  *£>
                                         r-4  i-t
                                                                               r- CM
                                                                                                  cr>
 tn
 (U

•H
o  e
u  Q»
r-IOO^fOOOOOOOOOO
                                             ooooooooooo
 CD
 3
 O
•H
 M
 10
    -Q
    CL
    a
                       m in     r-4
                        •   •      •

                       rHrHOHOOOO
                                                                    in
                                                                                       in
41
 (0
 0)
 -g
   o  o -H
m  o  o H
                                      CN
                                      ro
                                      vo
                                                         m o
                                                         CM CM
            oooooooominmooo
            orooooooo^ooooo
                                                        ooooooooooo
                                                        OOOOOOOfOOOO
00
 10
            0)
            -p
            (0
            p
            ro
                                                                    »
            Q)
            O
            10
           tH
            ft
            •0
            C
            (0
            en
                                                             144
-------
 03
 C
 o
•H
 o
3
            03

            Q)

            4J
            3
            CJ
           -H
            fO
            Ok
                                                      o     m
                                                                                                                       00
                                                                                                                       n
 fi
 rtJ
•H
               ,—                                in

                Qi     CNOrHOOOOOOOOO      OOOOOOOOOOOOO
 03
 3

 O
                       m
                       ro  ro  in
                                                                                                               in  in  o
 flj
4J
 a

 03
 M
 Q)
4->
 0)

 1
 n
 (0
04

 u
•H
 n
-p

 I
 0
 w
 (U
            X
           O
               ,
            OCL
                Q.
                                                                        00
                       tH^r-l
                                      r-(l-f^l
                       oooooooomooo
                       COOOOOOOOHOOO
OOOOOOOOOOOOO
Or-IOOOOOOOOOOO

(H^VDr--COCr>OiHfMrO
                                   r-H rH i-H r-l
 
-------
 CO
 c
 O
•H
.p
 fl
 O
 O
       CO
       0)
       -p *-»
.-1 I

 ss
-H  &l

 Vi >*^'
 m
04
(^^ "^J*
-------
 w
 c
 o
•H
J-»
 to
 u
 0
 en
 0)
-P  —
 ten
H  l
 o  S
 u
•H  tr>
•P  a.
 M  —'
 m
04
 c
 (0

 0)
 ®
 E
•H
 EH

 CO
 3
 O
•H
 M
 rtj
O
U
    a
                  in         in  m     T}-

           OO     rH  O                OOOOOOOOOOOOOO
       r*»»  to  r**                ^n                    oo     IA     CN  in

inOOrHrHiHiHOOO         OOOO     r*  "*  O     i-lCNOOO
                                                                                                      in
•P
 10

 0)
 H
 0)
-P
 
to
Q





-------
 c
 0
•H
-P
 (0
 u
 o
           to
           0)
           4J
           
           o  a
•H
EH
           omooooooo
           ooooooooo
                                O3OOOOOOOOOOOOOO
                                ooooooooooooooo
                                rHCNfO'<*ir)vor~«ooOr-icNn'^
-------




en
c,
O
•H
1 I
4-»
(0
o
o
CO
0)
-p ^
/H CO
IU " I
rH 1
3 2
0
•H cn
-P a
I. -_j
M *•**
a
&4

                             V0  rH
                             oo  o
                             rH  CN
 05
 a;
 e
           o  a     o o  ro  o
           o
 (0
 D
 0
•H
           O  CL>    \T) O  CD
           g  a    m r-t
 W
 M
 Q)

 •P

 1
 (0
            X.Q             «3 O
           O  CL            MO
 O
-P
 0)

 o
 n
 cu
               Q.
               a
           
rH

•8
EH
          -P

           «

          Q
           Q)
                      C
                      O
                     4->  (U
                      tn  n
                      c  m
                     -H  S
                      6  «
                     rH iH
                     -H  Q)
                     5  Q
                                                     149
-------
            to
 CO
 c
 O
•H
-P
 a!
 O
 O
           4J
            (0
               I
    2
H
•u  tn
u  o^
ra «-»
ro  ro n
CN  CN CN
                                         o  o
                                         m  ro
                                                                           co  r-  m
                                                                           ro  m  VD
'O
 G
 (0

 to
 Q)

•H
 EH

 (0
 D
 O
•H
 M
 m
    cx
O  CL
a  a
               in
                          in
                      f)
                                         O  O
                                         CO  iH
                                         i-l  ^H
                                         oooinoooineNOOOinin
 (0

 to
 i-l
 
                                                    rH  rH  rH  rH
                                                 ooininooommoin
                                                 cnin^onoocN^tfo^oor-
                                                 rH  i-H
                                                                                              in  in
               ,       m oo  CM  m  i
           rH   M
            m   m
           «  s
                                                     01
                                             CM
                                                        150
-------
 03
 C
 o
 •r\
 -P
 m
 o
 o
 0)
 -P ^
 n3 ro
 r-<  I
 3  S
 U
 •H  &>
 -P  D
 M •—
 m
 (0
 0)

•H
 EH

 01
 D
 O
-H
 M
 (0
     a
     a
    ^     o
    ,
o  a,
a  a
4J
 (0

 CO
 H
 a)
4J

 I
 a
 M
 (0
cu

 u
•H
 n
-P

 I
 o
 M
 (U
0,
           o
           CN
           rH
           m
o  a
    a
           o
           o
           oo
 Q)
rH
^J
 (0
-P
rO
Q
                      CN
            (U
            U
            a)
           -H
           CM
           0)
           M TD
           o  n
           E  fl
           •H r-t
           -P  >1
           rH  H
           ra  «
           cq S
                                                      151
-------
            w
 m
 G
 O
-H
4J
 m
 o
 o
           •P  -^
           10 en
          .-i  i
           3  £
           U
          •H   U>
          -P   a

           (0
              r*  co -
-------



• t
CO
G
O
•H
-P
(0
U
O
•O
G
CO
(U
£
CO
3
O
-H
J_l
(0
4J
id
CO
U
0)
4J
(1)
e
(d
M
0<

U
•H
M
•P
0)
e
o
5-1
0)

CO
Q)
•P -^
rH 1
3 S
U
•H tT*
•H ^
W ^"^
(0
CM



^
o s
O*«\
S1
QJ

«^
f)
O Q.
^4 Qj
*-*

•*•>
o a
2 QJ
<^*





fO iQ
O QJ
a
**-*




0)
-H
EH




o^rr^^'rHr^rHinvDtNinro^'VjOf'irHinn o^
oococoooc!>coc'^c'^r^r*cy>O'Hoocj>o rnro
rH rH rH rH rH rH rH







in in in tn tn in in in in
• * • * • » • * •




oooooooooooooooooooooo




Q\ f—j] \fl \£ p^ »QQ ^^ (JQ ^0 f^ 0^ ^^ Q\ ^ji f— f \Jft f^ QQ ^Q ^Q (^
rHCNrHrHCNrHCNrHrHiHrHHrHrHCNrHrHlH^r MCN






oo o CN o co oo r^ co o cyi in CN vo m oo vo rH o^ vo »H o ^
«^f¥1
-------
 (fl
 c
 o
•H
4J
 IT)
 0
        W
        0)

        m

        on
        u  i
        ID   O.
        CU  —
           CM O
           (N H (N
                              iH H  ro
ro  r» m m  in  Is- in
n  co ^ ^*  t"»  co CN
rH  iH rH rH  rH  rH rH
 c:
 m

 CO
 V

•rl
 EH

 to
 D
 o
•H

 m
                                         m in                            m

                                     r-IOOr-)rHrHiHrHrHiHrHrHi-l
                                                                                            in  in  m  m
        O  Q<     O O  O  iH
        [2J  Cu
                          rHOOOOOOOOOOOOO     OOOOOOO
 (Q
 H
 0)
 .p

 1
 IQ
 >-l
 m
 Cu
 o
•H

 -p

 I
 o
 0)
            a
o  a
    QJ
        i
        •H
        EH
                      (NrOtN(MiHrHOlrH
H

IT)
EH
        4J
        m
        a
        
-------
 0)
 c
 o
•H
-P
 fC
 u
        to
        cu
       •P
        (0 *-*
       rH CO
        3 I
        u 2
       •H
       •4J  &>

        ro -3
       ft ^
           S
       o  a
                                                          m in
                  i-t rH rH  rH
                                               H H  iH  rH
                                                                               in in  in            in  in  in
       oa     oooooooooooooooo
       iz;  a
                                                                               ooooooooo
       ox-a
       I3  0^
                                                         rH^DHnCM     CMCMrHrHCMCMvO^CM
                                                         rHi-HCMrHi-H     rHf-lr-ll-HrHrHrHrHrH
       o  a
           QJ
 e
•H
 E-i
                 OOOOOOOOOOOOO
                 OOOOOOOOOOOOO
                                                                 irt
                                                                    OO
                                                                    OO
                                                                               ooooooooo
                                                                               ooooooooo
                         rHrHrHrHrHiHrHrHrHCMCMCMCMCM
rH


 0)
(0
EH
 0)
-U
 (0
0
                  CM
                  X
                  c
                  o
                                                                               in rj<
                                                                               CM r-
                                                                              X 
        o
        (0
       iH
       (X
                      o
                     -rl
                                                       155
-------
 M
 C
 O
•H

 1C
 o
 o
        to
        
-------
 CO
 w
 c
 o
•H
•P
 (0
 O
 (On
rH  I

 ss
-H  tn
 a
•a
c
(fl

w
0)

•H
EH

tn

o
•H
M
(0
       o  a
       O  D'
                           >n  in m  in
       oa    oooooooooooooo
       2  a
                                                                        m


                                                             (NoolCM
                                                                 •>* CO CM CN rH
                                                                    ooooooooo
                                                                    ooooooooo
 CO
 CO

 rH


 0)
       a>

       at
       a
          VO
                                                             CN
           fi
           o
 o
 a
                  C
                 •H

                  e  o
                 rH  -rl
                                            157
-------
 to
 c
 o
•H
-P
 «j
 o
 n
 0)
-u  -»
 (CfO
r-l  I
 3  a
 o
•H  tJi

 H  -^
 m
On
•st  m i-i
•<*  r- r-
 m

 to
 Q)
    ta      in
O  u-
O  QJ     
-------
 m
 C
 o
•H
-P
 m
 u
 o
            tn
            ai
            •P
 u
•H
4J
 M
 (0
    CP
    3.
'C
 c
 (0

 03
 0)
 e
•H
o  a
o  *•"
 tn
 a
 O
•H
CO-     OOOOOOOOOO
                                                                 OOOOOOOOOOOOOO
4J
 tO

 03
 H
 (U
-P
 Q)
 £
 rd
 J-l
 (0
 o
-H
 M
4J
 0)

 O
            o  a
                CL
            e
           -H
                                      in  oo oo
                                                                        ri     in          mininm
                                                                         •       •           ••••
525  a     CM
                          cn  
                                      vr>
           OOOOOOOOOO
           OOOOOOOOOO
                                                     OOOOOOOOOOOOOO
                                                     OOOOOOOOOOOOOO
 0)
1-1

•8
 0)
-p
 (0
Q
            0)
            O
            (C
            ^
            04
            o   c
            (0  -H
           ^W   «J
            0)  -P
           -P   C
           -H   O
                                                         159
-------
 w
 c
 o
•H
+J
 ro
          CQ
          0)
          4J
rH I
 D S
 U
•H  &1
•u  a.

 m
cu
                                            co  .H  .H co co oo
                                                rH  «H
                                                                                                CTi
•o
 c
 ro
 w
 0)
 E
-H
O
u
 CQ
 D
 o
              a
                   oooooooooo     oooooooooooooo
 (0
 M
 <0
 4J
 (D
 g
 fO
 VJ
 n)
 o
-H
 M
4J
 0)

 O
 M
 (U
             —x    in  m
                                ininm     in    r\i    in     oo^mm        inm
   .
ocu
S3 a
              a
01
                                                                              ••*
                          CN
                                   co  o  m CN ro
          oooooooooo
          oooooooooo
oooooooooooooo
OOOOOOOOOOOOOO
 <0
 r4

 •8
0)
-P
(0
Q
                       
                                                       00
          0)
          o
          1C
          rH
          CU
          cu
          o  c
          1C  -H

          0)  4->
          -P  C
          •H  3

          S2
                                                160
-------
 W
 C
 O
-H
-P
 tO
 U

3
            W
            QJ
            -P —*
            (0 n
            rH  I
            3 2
            u
            •H  tyi
            -P  A
            M -—'
            (0
rH  rH in
rH  i-H rH
                          r- 10
                          in -?j.
                                         r»
                                         in
 n

 8
•H
 EH

 CO
 D
 O
-H
0
u
OQ-    OOO      OOOOO
 (U
 .p
 0)
 e
 (0
O
•23
               ^^    00  CM  f>
                        .    .   .
                      (N  
-------
      aJ
      D.
      O
      u
      c
       X
     c
                         03  ctf      cCojcticd      c3  ctf  03
      c/:
 I

i-H

tO     TJ
      I-H

CO    U
K     CM

OS    CJ
      U
      u
OS

2
E-
U
<   u

CO   C_3



      to
<   i-H
01   r-t
LU
i-J   I-H
oa    to
<   a:
H   u
              II      .0,0




              I   03      03  OJ




             o3  cd      oi  ctf





             OS  03     J2   i
                                      '  -O ,0   i
                                                                                     rto3o3c3rtcCctfa3      ctf  ctf  ctf
                                                                                                                           iiii
                                                                 oS      rtrt      ,0   i    i    i    I    i    i    i        1111
                                         ctf  cti  n3      c\3  oj  n3
                                     ri  oj  o3  o3
                                                                                      rtrtrtrtrtrtrtrt
              i   rt      rcrt       i   rt  rt   i       rtrtrt      rtrt
             rtrt       irt      rtrtcdrt
                                                                         rtrt      i    i   ctt  rt  rt  rt   i    i       rtcflctirt
             rtrt
                                     rtcSrti       ai  ni   i        11        iiictirtiii       rtcflicti
             ctirt      cticti      rtcdctirt      ccrtrt       rtcti
                                                                                                                           ctirtrtctj
             ctirt
             cflcj      ,c  ,O
              ii       nil
                                     ctJctirtct      rtrtcC       ctirt
                                                          ill       ii
                                                          ill       ctfi        1^X1X2X3,011       1111
                                                                                       11111111
                                                                                                                                              N1  CN  i-H
                                                                                                                                               I    I   I

                                                                                                                                               O  O  O
                                     cdcdcdcri       rtojoj       c$ctj
      WOOCT.      I^OC                                  O
      H     i—irn      rgrsi      Cxit-  +j       CO
      J     t> •-;        •  -i-l       rt   O
      a.    y:z      zu      LOZ
                                                          E   •          +J          SO
                                                         i—I i—I          i—I    *      i-H  'H
                                                         •H  a)          nj T3      -H  x
                                                         S o          ca s      s  c
o
cfl
O  O  U
w  t/1  t/)

II   II   II

O3 Xl  O
                                                                  162
-------
r-
r-
 t
<-\
ro

M
O
•rH
 QJ
 10
 3


 M
H
ro   O
O     Q


 I       I
                                       CM
                                                  o
                                               "31
                           .-I
                           U
                                                    U
                                                    a
                                                      CN
U
U
                                                                                            fa


                                                                                            i
                                                                                      ffi      1

                                                                                      U     fa


                                                                                       lt
                                                                                           X
oa
en
                                                          163
-------
 CP
  cu
  cr
  a:
  '.j
  o
  _i
  cr
£
  a:
  U-J
  i,~
     r#
  06'Z
•z
                    9dd  'NGIlbyiN-33N03
                              164
-------
          Z.05
CONCENTRATION,  PPB
 Z.10     2.15     0.20
0.25
2.30
                                                        rn
                                                        D
                                                        en
ro
ro-
                                                     r o>
                                                     ! 5
                                                     o, •*=
                                                        O
                                                        o
                                                        X)
                                                        03
                                                        03
                                                        O
                                                        m
                                                        <
Cu"

ea
M'
Q
O
                          165
-------
                                                                            S)


                                                                            "rj
   GO
   _J
   UJ
   >
   UJ
   o
   ca
   cc
   cr
   CJ
   CD
   _1
   cr
   ar
o
h  CT)
a  -
•rt  V^
"•  CD

   I—
   or

   CD
   a:
                          9dd
                                      166
-------
15
                 CONCENTRATION.  PPB
                  Z. 30     12.45     0.6S
0. 75
0.90
cs
                        167
-------
                                                                                 ea
                                                                                 (SI
Zf:
                                        168
-------
CONCENTflfiTInN.
 5.CZ     7.50 .
                                  10. Z2
12.50
15.22
o
                       169
-------
170
-------
                CONCENTRATION.  PPB
                  s.eu     7.52     iz.zz
15.
                                                     rn
-------
in
to
  LU
  >
  uJ
  O
  QD
  QC
  CE
  LJ
  O
  _)
  CT
  X
  o
  CD
  26 'Z
'2
                       '-j
                                  ibblN
                                 172
-------
                   CONCENTRATION,  PPB
           0.60     1.20     1.63     2.40
3.00
 (59
 t;
JL"50
                                                          3D
                                                          •z.
                                                          o
                                                          o
                                                        •n O
                                                          ro
                                                          -j
                                                          JC.
                                                          O
                                                          o
                                                          33
                                                          33
                                                          CD
                                                          O
                                                          m
                                                          (—
                                                          CO
ss
Si
                           173
-------
2)6 'Z
           0£'0
'NOIlbblN3-JN03
                                         ST -0
                         174
-------
                CONCENTRRTION,  PPB
         2.60      1.2C     I.82     2.HZ
3.02
3.60
J="


PS
                        175
-------
9dd
       176
-------
                 CONCENTRfiTION,  PPB
         Z.63     1.23      1.82     2.WB
3.
60
                                                     CO


                                                     2

                                                     O
                                                     rn
                                                     o
                                                     o
                                                     -J.

                                                   •a v.
ru !
                       177
-------
                                                            IS

                                                            CJ
                                                            -3-
                                                            rj
                                                         a i
                                                            rj
                                                            IS


                                                           I-S"1
O
DO
or
a:
or
o
o
X
a:
CO
                                                            IS
                                                              a

                                                              u_
                                                              o
                                                            ea


                                                            tc
                                                     •!  XI
                   8dd  'NOIibldlN'J3NG3
                                               si -
                            178
-------
                  CCNCENTRfiTION.  PP3
                   1 .20    - 1..8B     2.. 10
3.ZZ
3.60
oo-
o
CO
         m
         <
         m
 .
SI
Si
                          179
-------
o

CD
                                                                                       ta
                                                                                       6D
                                                                                      -!M
                                                                                       rj
                                                                                       ea
                                                                                       ea
                                                                                       ca
                                                                                       ca
                                                                                       ca
                                                                                         Q

                                                                                         U_
                                                                                         O
 ca
 o

-OJ
                                                                                       ca
                                                                                       ca
                           0Z'0
                            9dd
                                         , T •'
                                              180
-------
                 CONCENTRRTION,  PPB
                  0.52     2.7
i.ez
1.25
                                                       en
                                                       —-\
                                                       o
                                                       o
                                                       rn
                                                       i—
                                                       :D
                                                       2:
                                                       OO
                                                       CD
                                                       O
                                                       ni
                                                       
-------
-------
                 CCNCENTRRTION.  PPS
,p.zz      0.05      a.ie      z.is     2.20
Wj	i	|	I	!
Z.25
 2.30
	i
                                                        O
                                                        —»
                                                        O
                                                        3D
                                                        z:
                                                     2  rn

                                                     H  -o
                                                        -vj

                                                        JZ
                                                        o
                                                        o
                                                        D
                                                        JO
                                                        CO
                                                        o
                                                        2T
                                                        rn
                                                        <
                                                        m
CO
ea
                          183
-------
                                                                      fcj
at -0
                                   184
-------
CONCENTRRTION,
 Z.5Z     2.75
       PPB
        1.00
1.25
1.50
                          m
                          <
                          m
                          r—
                          en
185
-------
CJC
CO
                                                              (SI
                                                              3-
                                                              rj
                                                             KT
uJ
O
CU
cr
cr
o
o
_j
cr
» 1^-
^
a Q
£ 2
  u:
or
cr
UJ
cc
o
                                                                O
                                                                T:
                                                                U-
                                                                UJ
hC'Z
         ZC'Z
                     9T '2

                      8dd
                           NOIibcilN33NG?
                              186
-------
      CONCENTRATION,  PPB
'15     £.3(3     8.45     3.5Z
V  	1	1	L.
                 2. 75
Z.92
187
-------
                                   63
188
-------
         Z. 15
CONCENTRATION,  PRB
 Z.33     Z.45     B.6Z     2.75     0.9Z
                                                    m
e.
c.
                         189
-------
190
-------
       CONCENTRRTION.
e.is      z.az      3-""
                                             e.75
2.93
sr
                                                        O
                                                        z"
                                                        O
                                                        n:
                                                     •B
                                                     )•*•
                                                        ~
                                                        O
                                                        O
                                                        3D
                                                        00
                                                        CO
                                                        O
                                                         m
                                                         r~
                                                         LO
                           191
-------
                                       ea
                                       is

06-0

Si ''0 09 ''0 5V1 8 0£ -'0
9dd 'NOIlb!diN13N03

PJ
CJ
cjl''0 ' 02 '2T'
192
-------
CONCENTRRTION,
 Z.16     B.2H
                                   0.3,
0.40
CO
ea
                                                     O



                                                  -d  *sj
                                                     o
                                                     o
                                                     ns
                                                     o
                          193
-------
194
-------
                CONCENTRATION.
         2.15     0.33     Z.45     0.62
                          '        I
KS
ea
                        195
-------
                                          ca
                                          CJ
196
-------
Z.1S
                 CGNCENTRfiTION.  PP8
                  Z.3B     Z.qS-    Z.62
                                                      . o
                                                      X
                                                      •—«
                                                      o

                                                      -J
                                                      \
                                                      r\>
                                                      o
                                                      o
                                                      35
                                                      00
                                                      CD
                                                      O
                                                      2
                                                      m
                                                      <
                                                      rn
(SI
                         197
-------
                                                                           (3
Qfi'0
                                  198
-------
               CONCENTRRTION,  PPB
                Z.33     2-^5     0.60
0.75
0.90
CD
M
.c-'
                        199
-------
  UJ
  r>
  uJ
  _J

  z.
  o
  CO
  or
  a:
  o
  o
  _i
  or
  3=
   CD
Ol
   O
   s:

   uJ
   (_»
   CT
   u_
   UJ
                                                                                        LLJ
    CiC'Z
~^2
                                            T '2!
                                           200
-------
J-J£
                CCNCENT3RTION,  PP8
                  z.12     s  is     a.Z4
.5.30
Z.3S
C3
                        201
-------
   CO
   _l

   UJ
   >

   uJ
   O
   CD
   or
   cr
   o
   o
   _i
   cr
    r~
o
in
o

I
cn
    O
     C_J
     uT

     u_
     UJ
                                                                             isa
                                                                        !    -3
                                                                        i    o
                                                                        !    :r
                                                                             !'  o
                             add
                                          202
-------
 I.B'J
3.Z6
CONCENTRfiirCN. PPB
 2.12     3.13     E.24
2.30
CJ
M
                         203
-------
  CT>
  UJ
                                                                                      eg
                                                                                      IS)
                                                                                      IS)
                                                                                     !SS
  cr
  CO
BO
i-l
CX.
 cr
 i—
 z.
 -j
 o
 5T

 LiJ
 O
 LT
 U_
 UJ
GE'Z
                                                                                   »-~Cr
                                                                                       o
                                                                                       "S>
                                                                                      I-
                                                                                   I 'J
                                                                                   , *-,
                                                                                   L
                                         204
-------
C.ZS
                  CONCENTRRTION.  PP3
                   2.12      3.18      0-24
 0.33      0.35
__i	j
                                                      1
                                                          rn
                                                          -n
                                                          X>
                                                          o
                                                          o
                                                          c:
                                                         CO
                                               CXl
                                                         35
                                                         (—
                                                         O
                                                         o
                                                         35
                                                         00
                                                         CO
                                                         o
                                                         m
                                                         f—
                                                         U5
c-.
C.J
                         205
-------
  o
  
  CO
o
a. LT
  O
  LJ
  cr
  o_
  UJ

                                                              I  >--
           ZC
                      add  4NOIibbiN.13NOD
                                206
-------
                  CONCENTRRTICN,  PPS
                   2.i2     .-MS     3.24
                    1	1-	1
                                                         rn
                                                         ~n
                                                         3D
                                                         o
                                                         O
                                                         c:
                                                         
-------
       cT       .    ,?.
10 / --> K' b U 3 0 b .  I ki
                  i u
"08
-------
                                                                                  ca
                                                                                  es
                                                                                 r?-
                                                                                  i-r
  or
  i—
  CL
  O
   CD
   2T
   o:

•J  =**
"  r-
    CD
    cc

    o
    cr
    UJ
                                                                                      o
                                                                                      or
*,
 I i
                                          209
-------
                                                                       (SI
   cr
   i—
   a:
   ffl
   2~
   ir


   r-

   r-
•n
•ri
   o
   UJ
 20'ZG
Z2
Z2
zz •:
                                                        'cJO  Sdd
                                      210
-------
                                                                            IS)

                                                                            (S)
   cr
   i—
   cr
   o
   CQ
   5-
   a:

   ^
   r-
   \
   CO
   rj
4>
fe
B.  •— •

   O
   DC
   O
   UJ
                                                                            is)
                                                           NS Ll_.
Z3"2G
"^     ZZ'ZS
                                               22'2c
22 'r,:
 yo
4,
 7
                                      211
-------
PPB
    METE"
162.22     222.22    ^<^*  22
                                                       o")
                                                       _h>
                                                       a
                                                       —c
                                                       CO
                                                       rj
                                                       -^
-------
  CT
co
1/1
?
I
i-t
u.
O"1





Ci
r—,

in

•>—
Cj


or
                    'ZS\     22
                     3i8n:/c
•*2\
                                         ZZ
                                                     JJ
                                 213
-------
            'Zb     ZZ'Zt-
            1 IN  'd 0  9 J J
214
-------
                                                                                           K)
                                                                                           (S3
                                                                                           (SJ
                                                                                            CSS
 .  a:
   CD
   2"
   cr

o  rr
   o
   o
   a:
   D
   Z
   vX
                                               215
-------
vO -,



8^
3 :s
oc  r
•H ' L

*• _J

  LJ
  o
ZZ'Z2>
                     zz'z??    zz'zr,:
                                          zz'z?:     zz'zs.
                                           'tJOih yo
                                                                     •::u:
                                                                       o
                                                                       O
                                                                     ts)

                                                                     to



                                                                     (T
                                                                     (S3
                                                                     ts)
                                   216
-------
    or
    i—
    or
    a
    CD
    27
    a:


    r--

    cn


fM
*°   UJ
fl)   Q

•H   ^
B.   a:
    _j
    LLJ
    O

    z:
    o

    o


    1C
    -J

zz

1
'Z2L


ZZ

i
•zsc
ci31

22
3K
— i 	 1 —
"OHP oio'^rr
t^ ^- C t* *-> «-j i .
oign'j/s^bc

zz
J30a'
I
'2?:
j i K


yo

22
t"1
— r 	
•Z'.,
Jd
	 r-
;'.:• ?,

                                                217
-------
or
                                 218
-------
cr
                                  yo add
-------
  or
  i—
  a:
                                                                    (S3

                                                                    •SI
  oj
§>
  or
  o
  a:
  CO
ZZ'ZK    ZZ^ZST
                                          ZZ'Zb     ZZ
                                            ih  yo  a
                                 220
-------
cr
                                221
-------
                                                                IS)

                                                                "MS
  cc
  Q
  *
  on
  5T
  cr

  rr
  r—
a"
•H r—,
n_ '—'
  O


  U)
                                                               1 -O
ZZ'ZZJ
ZZ'ZSI
                                        ZZ'Zb
zz
                                222
-------
                                                                                   (S3
cr.
                                    223
-------
cr
                                                                    IS)




                                                                    rj
                                                                    IS)




                                                                    i"j
                                                                      o
                                                                      JT
                                                                    IS)
                                                                    is) 11 ;
                                                                    IS)

                                                                    IS)
n	1	r
21     ZZ'ZG     ZZ'Z?
          ik  yo  g<
                   20'Z9I
ZZ'Z'
                                 224
-------
 or
 i—
 cr
 o
 aJ

 CD
 5:
 a:

 rr
 r-
0
  rf
  CM
   o

   o
  00*0f
                                    225
-------
                                                                  S3
  CT
  I—
  cr
  o
  mi

  GO
  2~
  or
  in
  r\j
«  o
f-l  .	.
li.  O
   O
                     00 '091
                U313W  :
                                                     00
00*0^
                                  ^26
-------
                                                                         63
cs
t-
cr
i—
cr


i—
2
UJ

CO

(X

IT
   CG
   ru
lo
   O


   2
   O
   I—
   LD
00-091
                              02'02I
                                             00-08
                                                                         ru
                                                                         K)
                                                                         K)
                                                                         K3
                                                                         Kl
                                                                        "—or
                                                                           x
                                                                         ca
                                                                         R3I, j
                                                                         IS)
                                                                         (S)
                                                    yo  add
                                    227
-------
                                                                      1S1
                                                                      ca
  OC
  a
   aJ

   CD
   5:.
   CE
R
•H
u.
   o

   CD
                                              00-0&     00'*?"
                                                    yo  9dd
                                    228
-------
   cr

   cr
   CD
   r-
f-


(-
ZZ'ZE     Z2
ZZ'ZS     Z2
ZZ

Sdd
                                                               7-Z
                                 229
-------
                                                                   IS)
cr
i—

0

t—
zz:

t—-*
CD

CE



r~

z.
-3
o
o
cr
                                                                  h
                                                                   (SI
                                                                   IS)
                                                                   IS2 _^

                                                                   -^
                                                                   — or
                                                                     ~o
                                                                     0
                                                                     T-
                                                                   'SI ""
ZZ'I/.      ZZ'ZS
                              22 "F
                                         ZZ'Zc     ZZ C,I
                                        bDih  uo  ajj
zz
                               230
-------
                                                            IS3
  cr
  i—
  cr
CD

cr




CO

\
en
£ -
  o
  2:
                                                            rj
                                                         W
                                                             O
          W1L
00 "0S
02
                     31903/9
00";
   22'$ i
UG  add
                                                      22 '
                             231
-------
                                                        (S3
                                                        IS)
02*36
            J313W 319037
22 '2'
                            232
-------
(HdW)Q33dS QNIM

     cvi      O

                                             o
                                             o
  w
  \-

  UJ
  2
  UJ
  (T
  UJ 00
  2-
    o

  o
  a

  1
   g
   o
   UJ
   en
       i I I
                                                                       CM
                                                                      00
                                                        OT
                                                        (T
                                                        X

                                                      CVJ I

                                                      " UJ

                                  I

    10 CJ —
        GNIM
  (SA319NV1)
A1ISN31NI
 8

qdd
                                   233
-------
(HdW)Q33dSaNIM

     8      O
                   (SA3"19NV1
                 AilSNBlNfHVIOS
qdd
                                 234
-------
(HdW)Q33dS QNIM
                                CM
    (833^930)
    'ma QNIM
   (SA319NV1
A1ISN31NI
qdd
                                235
-------
(HdlMHSdSONIM
    8     O
    tOCJ —

    (S33y93Q)
        QNIM
   (SA319NV1)
A11SN31NI HV10S
qdd
                                  236
-------
The maximum, minimum and average data of Table 13 for all the halogenated
compounds are indicative of a complex variable emission pattern and a
strong dependency on meteorological factors and should be representative
of the lower and upper limits one can expect at typical urban and non-
urban locations.  However, the Bayonne, N.J. data show that, at times,
meteorological conditions are probably more significant than local emission
patterns.  At this location not only were many of the maximum but also
minimum halocarbon readings obtained.  The frequency of minimum halocarbon
data in Bayonne, N.J. was understandably quite low when compared to rural
area data, for example the Whiteface Mountains.  Representative levels of
halocarbons that one can expect in urban and rural areas are given in
Table 14.  Also included in Table 14 are data indicating a dramatic
increase in halocarbon concentration as one enters an inversion layer
from aloft.
The apparent ubiquitous nature of CClsF, 00^2, CH3CC13 and CC14, the
probability of their near exclusive anthropogenic origin, their signi-
ficant emissions, their low solubility in water, and theoretical chemical
and biological inertness all suggested, early in our experiments, that
these compounds would continue to accumulate in the troposphere and upon
photolysis in the stratosphere play a significant role in stratospheric
chemistry.  However, there were insufficient data on CClgF and CCl2?2
and no data on CC14 and CH3CC13 which rigorously precluded their reactions
with typical reactive tropospheric species such as OH- , 0-, RO', etc.  The
tropospheric stability of these four compounds is unequivocally demonstrated
in Figures 82 and 83.  In these experiments kj for NC>2 photolysis was
0.39/min.  Accordingly, in terms of total energy input, our laboratory
irradiation times are equivalent to much longer tropospheric irradiation
times.  Similar experiments were conducted in which characteristic reactive
hydrocarbons were also present.  Again, with the exception of the small
initial decay attributable to surface adsorption, these halocarbons were
stable.  Since NC>2 was replenished periodically (up to 50 pphm NC>2 ever/
24 hours) during the course of the irradiation, reactive tropospheric
intermediates were continuously available for reaction with the halo-
carbons .

While atmospheric CC13F, CC12F2 and CH3CC13 are clearly anthropogenic,
the occurrence of CC14 in the atmosphere can not be accounted for from
direct production emission data*-   '  J.  No valid explanation for the CCl^
budget is available to date.  Promising research in this laboratory
supports the possibility of considerable atmospheric CClq formation by
the photodecomposition of chloroalkenes in the troposphere (  J.

6.2.2 "Non-Ubiquitous" Halocarbons -

€2*^14 was measured at concentrations exceeding 0.06 ppb at least 50% of
the time at all locations.  In a short-term monitoring effort in New York
City, levels as high as 9.8 ppb were observed.  Similarly, CHC1CC12 was
observed over 90% of the time at all urban locations  (except Baltimore)
at concentrations exceeding 0.05 ppb.  A large clean oceanic air mass
had moved in during the Baltimore monitoring, which probably accounts for
                                    237
-------
  i tr
  o: o


  P
  10 u
  4- a:
  CM w
  E o
  4L x
f^ "*~ ff
00 ^_ **•

111
   o <
   ffl z
   a: -
   3
                                                         o
                                                         o
                                                         '8
                                                         to
                                                          o
                                                          CO
                                                          CVI
o
^r
CM


   W
   
-------
_


s



fO
o
o
1
fO
> X
.c O
4- «*
X
or
u5 ^
CM (
o
z
1 <
o. **

i 2
M 5 CK
00 ** QJ
g Z H •
a- -« ••
"IB
CO c\l



? 1
in
8
CM


o
00

o
u>




o
2:


o
OJ
*~
a:
il
bJ
O
00

8


0
o
CM


0
239
-------
the absence of detectable CHC1CC12 as well as the generally low levels of
all other halocarbons.  At the non-urban locations,  however,  this compound
was undetectable (<0,05 ppb)  about 70% of the time.

Since the sources of C2C14 and CHC1CC12 are located  primarily in urban
areas, urban transport plays  an important role in their distribution.
However, superimposed on this is the tropospheric reactivity of these
compounds.  The tropospheric  photochemical reactivity of CHC1CC12 has
already been reportedW.  Figure 84 is a concentration-time profile for
the irradiation of a mixture  of 0.8 ppm C2C14 and 50 pphm N02 in ultra-
aero air (R.H.=50%).  02014 is clearly quite reactive and would be
expected to undergo significant photochemical degradation during transport
to non-urban areas.  Depending on the 02014 source strength,  meteorological
dilution, sunlight intensity  and the presence of other trace constituents,
02014 or its predominant product COC^ accordingly may or may not be
observed in the non-urban areas.  As is clear from Figure 85 the percentage
conversions on a chlorine basis of 02014 to 00012 is about 60%.  Recognizing
the need for a sufficient reaction time, we calculate that an ambient con-
centration of 10 ppb 02014 observed in New York City should lead to the
formation of 12 ppb COC12 (TLV=100 ppb).  Although quantitative data on
the 00012 yield from CHC1CC12 is not yet available,  COC12 has been
unequivocally confirmed to be a major product of the tropospheric photo-
oxidation of CHC1CC12.  The gas-phase phosgene-water reaction is probably
insignificant as a removal mechanism for COC^^  ), although particulate
surface reactions and reactions of 00012 with other trace constituents,
say NH3, may be important.  This clearly suggests the need for a program
of ambient measurements of 00012-  The rapid ozone decay in Figure 85 is
probably due to a chlorine atom ozone chain reaction similar to the one
proposed for the stratospheric ozone destruction by fluorocarbons f •*• ).

The lower frequency of detection of CHC1CC12 is probably due to a smaller
source strength(1^8) and a higher tropospheric reactivity^.  Additionally,
however, urban transport may not always manifest itself in increased ground
level halocarbon concentrations in non-urban areas due to the trapping of
urban halocarbons in inversions aloft.  The inversion data of Table 14
illustrates this point clearly.  All halocarbon concentrations measured
at this rural location at ground level were typically low.  Halocarbon
concentrations above 5000 ft. were similarly characteristically low.
Within the inversion layer however (1500 ft), halocarbon concentrations
were many factors higher, say 35 for CCl^F, than their corresponding ground
level or above inversion values.

CH3I, SF6, CH2CHC1, CHOI,, and CC12F-CC1F2, the other halogenated compounds
of interest, were generally measurable less frequently than 02014 and
CHC1CC12 and, for the most part, traceable to nearby sources.  The note-
worthy characteristic feature of tropospheric CH^I is its general non-
detectability  at locations remote from the ocean (Table 14).  Indeed,
Lovelock et al.^  •'found a 100 fold higher mean surface ocean concen-
tration than aerial concentration for this compound and suggested the
ocean as a source.  The lack of detectability at sites remote from the
                                    240
-------
                           uidd *
  4-

  is
  ? m
   I
   ID

   O
"-  II
2  UJ
|> o o ° J

  4- CJ  _ ^

  IPS

  z
  u
  CVJ
  u
                             241
-------
ocean is likely due to tropospheric reactivity (Figure 85).   It should
be noted that a ghost peak frequently appears at the same retention time
as CHjI when one uses a glass syringe repeatedly.   This is tentatively
attributed to heterogeneous CH$I synthesis from unknown ambient precur-
sors which accumulate on the glass walls.

The ambient SF^ concentrations were typically below 0.001 ppb although
levels as high as 0.005 ppb were observed  in New York City.   The latter
is attributed to leaks from SF6-dielectric high-voltage transformers,
or the only other probable source of this  compound, a nearby meteorolo-
gist conducting a tracer study.

The reported link between Angiosarcoma and vinyl chloride monomer (pending
TLV=1 ppm) prompted the inclusions of CH2CHC1 in the halocarbon ambient
monitoring program.  CH2CHC1 could not be  measured at all locations
(sensitivity >10 ppb) except at Delaware City, Delaware, where levels as
high as 1.5 ppm were observed.  These readings were obtained downwind
from a complex of chemical plants.  Experiments conducted in this lab-
oratory which will be reported in detail at a later date demonstrate
that CH2CHC1 is tropospherically reactive  and hence will not accumulate
in the troposphere.

Both CHC13 and CC12F-CC1F2 were detectable at most urban locations at a
relatively low frequency (sensitivity >0.01 ppb).   CC12F-CC1F2 exhibits
significant tropospheric stability (Figure 86) and should accumulate in
the troposphere.  Since CHCls absorbs radiation only well below the
290 nm tropospheric cut-off (CHC13 Amax =  175 nm)  it can only undergo
thermal tropospheric reactions.  Its structure however, suggests minimal
tropospheric decay by such reactions.

6.2.5  Ambient Variability of Halocarbons  -

Table 17 lists the eleven compounds measured in order of the "variability"
of the ambient values, as defined in section 6.1.   This quantity, though
extremely crude and statistically indefensible, nevertheless gives a
rough relative indication of the degree to which these compounds fluc-
tuate in their ambient levels.  Interestingly, the compounds fall rather
neatly into two groups - a "low variability" group with values of 50-70%
and a "high variability" group, with values of 95-130%.

With the exception of C2C14, all the members of the first group are tro-
pospherically stable, which no doubt explains their relatively constant
values.  CC14 is clearly the least variable compound, which is consistent
with the ideas already expressed regarding its possible sources.

The high variability of CH3l and C2HC13 is understandable in view of their
tropospheric reactivity, as well as the probable oceanic source of CH3l.
There were apparently high local sources of F113 at Bayonne, and of CHC13
at both Bayonne and Wilmington, Ohio, which contributed considerably to
the overall variability.

                                   242
-------
                           uidd '
I
a:
S5

8
0

"*
   s
   fc
^ O
Z O
— cvi
O


•-«
 ro
                                             ro   cu    —
                              qdd'NOIlVUlNBONOO
                             243
-------
                          iff
                          
Q-  f>

<  o:
o
CD
            cvi
                                            I
                                                                ro
                                                                 O
                                                                 TJ-
                                                                 CM
                                                                 CM
                                                                    UJ
                                                                to
                                                                  o
                                                                  CM
                      CM
                               in        O        m

                              ' NOIiVyiN30NOD
                                244
-------
6.2,4  Ambient Halocarbons as Tracer for Large Air Masses -

Because of their characteristic spatial and temporal distributions, wide
gradation of atmospheric reactivity, and amenability to ultra-trace
analysis, halocarbons are potentially useful for elucidating complex
atmospheric transport phenomena.  Figure 87 is a diurnal concentration-
time profile for 03, light scattering aerosol (LSA) and several halo-
carbons obtained at Whiteface Mountains, New York, a relatively clean
air site (LSA 20 to 60 yg/M^).   Ozone concentrations are seen to increase
gradually from 0800 to 2000 hours.  The net increase of 20 ppb from 1100
hours to about 1600 hours can be attributed to either tropospheric syn-
thesis and/or transport.  However, the ozone concaitrations increasing
until 2000 hours to a maximum of about 65 ppb can not be accounted for
by synthesis.  Since the halocarbons generally originate in urban areas
their concomitant increase with ozone and particulates is an unequivocal
proof of urban transport.  Stratospheric injection of ozone can be dis-
counted since this would be associated with deep vertical mixing and
hence, in the absence of significant simultaneous transport, a decrease
in halocarbon levels.  Stratospheric injection occurring simultaneously
with transport can be discounted since CC14 would have to decrease, be-
cause of its known decreasing vertical concentrations profile ^ ^ com-
bined with its uniform distribution in urban and non-urban locations.
This is clearly demonstrated in Figure 88  where the levels of CC14 in
New York City and the Whiteface Mountains are remarkably similar.  The
corresponding data for the other halocarbons shows their expected much
higher urban levels.

6.2.5  Seagirt monitoring - General comments -

At this location breezes were typically from the land in the morning and
from the sea in the afternoon.   The pattern of NOX and 03 levels on
6/19/74 is consistent with this (Figure 78).  In the absence of des-
tructive agents the ozone levels will remain through the night, an
observation made by others in some non-urban areas.  With the onset of
the afternoon sea-breeze, all the fluorocarbon levels dropped.  This is
especially noticeable with the ubiquitous compounds F-ll and HIT.  The
drop in CC14 is less pronounced, consistent with its relative non-depen-
dence on location.

The data here demonstrate that caution needs to be exercised regarding
samples taken by the ocean, with on-shore breezes, as being representative
of background.  At Seagirt, the halocarbon levels were clearly substantially
above background, concurrent with the Seabreeze.  In other words, polluted
air is being recycled.

6.2.6  New York City monitoring - General comments -

The monitoring site was in the heart of mid-town Manhattan.  Not unexpec-
tedly, the highest values for almost all compounds were registered here.
This is especially true of F-ll and €3014, which were each about an order
of magnitude higher here than at any other site.  Local wind speed and
                                   245
-------
to   5   PJ  _
d   d   o  d
   (qdd)-QNOO
       246
-------
'NOliVdlN3DN03
    247
-------
direction are largely meaningless because of the proximity of tall
buildings - however the general wind direction over the city during the
monitoring period was northeast.

Extreme fluctuations in all the measured parameters are apparent, again
no doubt due to the peculiarities of the monitoring site.   It is possible,
however, to discern the increases in nitrogen oxides during the morning
and evening rush hours.  On 6/27/73 there is even a peaking to coincide
with the evening theatre traffic in this area (Figure 79).

6.6.7  Sandy Hook monitoring - General comments -

On all four days, exceptionally high maximum ozone levels  were observed
(180 to 200 ppb).  On the first day (7/2/74) this high 03  can be
attributed to high hydrocarbon and NOX emissions from inland being
transported over the monitoring site (Figure 80).  The halocarbon levels,
which were characteristically higher than background, support this view.
At about 1300 hours the wind direction changed suddenly from north to
west.  The air mass from the west was probably more contaminated with
ozone precursors, since there was a simultaneous dramatic  increase in
C2C14 and, to a lesser extent, some of the other halocarbons.

NO was characteristically very low, which further supports the concept
of 03 formation upwind of the monitoring site, and is consistent with
the high 03 levels.

The monitoring period was just prior to a holiday weekend, with high
traffic density on the New Jersey Turnpike and other major roads, west
of the monitoring site.  CO levels were seen to increase concurrently
with oxides of nitrogen, as would be expected.

Because of the possibility of analytical artefacts in the converter of
the NOX detector, care should be taken in considering the N02 data.  The
N02 values could well include PAN, as is well known.

6.2.8  Wilmington, Delaware monitoring - General comments -

As far as halocarbons are concerned, this was a fairly "clean" site,
with F-ll and F-12 values as low as anywhere.  Except for somewhat
higher CH3I values  (due no doubt to proximity of the ocean), measurable
vinyl chloride, which has already been commented upon and lower CC14,
this location is not unlike the Whiteface Mountain site.  03 levels were,
however, exceedingly high, exceeding the 0.8 ppm standard.  The air was
clearly contaminated, but in a "non-urban"  fashion.

6.2.9  Baltimore, Maryland monitoring - General comments  -

As stated earlier, a large clean air mass arrived from the ocean during
the monitoring  period.  The air was thus much cleaner than  should normally
be expected in  an urban location such as this.  The very high NOX levels
                                   248
-------
(Figure 81) are almost certainly due to the proximity of local sources.
The site was only a few hundred yards from the tunnel entrance of Inter-
state 95, which was vented by large fans.  Also close was a D.O.T, main-
tenance building having very heavy truck traffic throughout the day.  The
lack of wind during the night would permit oxides of nitrogen from these
local sources to remain in the vicinity.

6.2.10  Wilmington, Ohio monitoring - General comments -

Based on halocarbon levels, the air at this site was considered to be
mildly polluted.  Surprisingly, CH^I was detectable on a few occasions,
despite its high tropospheric reactivity and the remoteness of the site
from the ocean.  A local source is possible, such as the one which
apparently existed for CHC13.  (CHC13 had the highest average value here
of any site, and the highest variability.)

The typical diurnal trend of 03 levels can be seen at this location, but
the absence of a diurnal pattern of NO and the high 03 concentrations even
in the evening, is indicative of transport.

A considerable amount of additional data was accumulated during this
monitoring period, as part of a collaborative effort with EPA.  For
example, halocarbon levels were measured in aircraft samples taken above
and below an inversion line.  A wide variation between the levels was
noted - for example, F-ll was 0.3 ppb above the inversion layer (6000 ft.)
and 8 ppb below it (4500 ft.).  All this data has been supplied separately
to the EPA and will no doubt be incorporated in due course into a full
report on this monitoring effort.

6.2.11  Whiteface Mountain monitoring - General comments -

The evidence for large-scale urban transport to this location has already
been discussed (Section 6.2.4).  Otherwise the site is the cleanest of
those studied, and the minimum halocarbon levels are probably typical of
background.  As stated earlier, agreement with background values reported
by others is quite good.

6.2.12  Bayonne, New Jersey monitoring - General comments -

This was the first site at which regular halocarbon analyses were carried
out.  Up till May, 1973 only F-ll, F-12, CC14 and CHsI were measured, but
after August 1973 the analytical procedures had been developed sufficiently
to permit measurement of F113, CHCls, HIT, TCE and PCE.  The data here
were taken over a larger period and less frequently than at the other sites,
so it was not considered worthwhile to compute daily averages, as has been
done in Table 15 for the other locations.  Monthly averages are given
instead.

This site showed perhaps the greatest variability of halocarbon levels.  The
highest values of all compounds measured except TCE (where NYC had a slightly
higher value) were recorded here, as well as the lowest values of F-ll, CC14,
-------
TCE, CHsI,  CHC13 and F113.   The site is  distinctly urban,  but  appropriate
meteorological conditions can evidently  provide typical  background levels,
on occasion.
-------
                                SECTION VII

                      PHOTOCHEMICAL REACTIVITY STUDIES

The compounds discussed in the following subsections (7.1 to 7.10) were
each subject to simulated tropospheric sunlight under a variety of con-
ditions .   Those which showed no evidence of significant decay under
tropospheric conditions were further examined for their behavior under
simulated stratospheric sunlight conditions.  The experimental details
have been described in Section 4.

7.1  F-ll, F-12 and F115

7.1.1  Results -

In all systems simulating tropospheric irradiation neither Freon-11,
Freon-12 nor Freon 113 reacted.  Preliminary investigations had indicated
that these compounds would not react; as a result the following experi-
ments were pursued:  Freon-11 and Freon-12 were irradiated in ultra zero
air at 50% relative humidity in Mylar bags for a period of 13000 minutes.
The system investigated contained Freon-11 and Freon-12 and N02-  The
nitrogen dioxide concentration was monitored daily during the course of
this experiment and was replenished in an effort to maintain a concen-
tration of 50 pphm N02.  Freon-11 and Freon-12 concentrations were also
monitored daily.  The same system was investigated in a glass reactor,
and identical experimental procedures were followed.  In both systems,
there was no net decomposition of either compound (indicated by no
decrease in concentration) as shown in Figure 82.  A similar result was
obtained with F-113 (Figure 86).  The aforementioned experimental scheme
was repeated with approximately 1 ppm hydrocarbon "A" in the system, and
the results obtained substantiated the previous findings (Figure 89).
Freon-11 was next introducted into the 72 liter Pyrex glass reactor.  The
investigated mixture was composed of Freon-11, ultra-zero air at 50%
relative humidity and nitrogen dioxide.  Nitrogen dioxide was replenished
daily to maintain 50 pphm, and Freon-11 concentration was monitored as a
function of irradiation time (almost 400 hours).  The result of this
experiment (Figure 90) indicated no net decrease in the concentration of
F-ll indicating no photoreactivity of these compounds in a polluted
environment.  A similar result was obtained with F-12.

Figure 91 shows the effect of simulated stratospheric photolysis on F-ll
and F-113.  In these experiments the halocarbons in ppb binary mixture
with zero air were irradiated in the 1-liter quartz reactor by the 450
watt high-pressure mercury vapor lamp.

7.1.2  Discussion -
The results presented above conclusively establish that these compounds do
not react chemically in a polluted environment under the influence of
tropospheric sunlight.  Their chemical inertness, and the fact that these
                                   251
-------
    QL
  2 >-
  O 5
  m <
                                                      O
                                                      O
                                                      rO
  a: < oo

  >° 5
  i tr <
  -L uj x
  Q N O

    <
8
2  «
o  x
CM  —

   LU

                                                          O
  _
  Q.  I-
  fei
                                                      o  5
                                                      o  <
                                                       "  a:
                                                          tr
                                  ro

                                add
                             252
-------
*
0 •
See
OH *>
S -1 d
F CM «M U.
b r- o o
2 < Z
3 — z «v
i§ x d
CM< (0 .CM
do z £
9,0: LU
U^LU _l
0 N OL
"* < !f
^ cc °-.
§ i b 0=
sl^g
s,y z o
bo l£ — ^
ou **• Q LU
r LU Q:
U- H <
ro < tn
_j Q tn
o ^ *t
0 flC -I
— cc o
~ u m
2 £ CC
IJ ^^ ^^
DC - "-
u. o <
0
1 0 i i iC


•

o








!

o



•
H , , , ,,














I
_


~

^

^r


-
1 . , , ,
O




O
8
w
cc
UJ
3g
1 §
5
o
^
oc
cc



o
0






000°
10 CM —
   8dd
253
-------
                          Figure 91


                  HALOCARBON DECAY IN A I LITER


                    U.V.Q2200A) REACTOR



                  HALOCARBON + AIR + U.V.
  100 i—
                                    CCA2F-CCfiF2
o.
o.
 ft

Z

O
te.
t-



\
o
o
                     20      30      40


                      TIME (MINUTES)
                          254
-------
compounds are transparent to wave lengths longer than 2900A^   •* serve to
substantiate our  findings that photolysis of these compounds does not
occur  in the troposphere.   Molina et al.*-  ^ have proposed stratospheric
photolytic dissociation of F-ll and F-12 to CFC12 and Cl, and to -CF2C1 +
•Cl, each reaction creating two odd electron species, a Cl atom and a free
radical.  The ultimate proposed sink involves a catalytic chain reaction
leading to a net  destruction of ozone and atomic oxygen as follows:

          Cl + 03 ----- > CIO- + 02
          CIO- +  0 ---- > Cl + 02

Figure 91 clearly establishes the stratosphere as a sink for these compounds,
From the slopes and a consideration of the average light intensity of
0.34 watts/cm  used in our experiments - a level some 400 times the solar
irradiance at the top of the stratosphere ("^, the respective half-lives
of CClsF and CC12F-CC1F2 of 10 and 31.5 minutes correspond to minimum
stratospheric half-lives in hours of 69 and 217 hours.

With the expectation of 10-30 fold increase in concentration of freons in
the atmosphere, based on the assumption that present fluorocarbon pro-
duction and emission would continue, Molina and Rowland'  ' calculated
atmospheric lifetimes in the range 40-150 years.  Stratospheric photo-
dissociation of freons, it was proposed, would produce significant amounts
of chlorine atoms, and lead to destruction of atmospheric ozone by the
chain process above.  In fact it was suggested C 190) that these compounds
in the stratosphere have already caused a 1% to 2% reduction in strato-
spheric ozone concentration, enough to cause an estimated 10,000 new cases
of skin cancer each year in the U.S.  Reduction in the level of ozone
which heats the stratospheric air as it absorbs radiation could also
cause changes in  glocal air circulation patterns and subsequent climatic
changes at the earths surface.  The overall effects on man are difficult
to evaluate at this time.  There could possibly be damage to the eyes,
sunburn ind aging of the skin.
It has, however, been pointed out' 19D that ozone concentrations less than
10% at atmospheric pressure and room temperature, the photosensitized
decomposition of 03 by chlorine is not a chain reaction, but has a quan-
tum yield of only 2.  Further, the radicals can react not only with 0?
but also with other atmospheric constituents such as ^0 and N02 to form,
for example, HCL03, HCLO^ and HN03.  Such competitive processes would,
of course spare the ozone from the full effects of the chlorine atoms
produced by u.v. photolysis of freons.

7.2  Perchloroethylene

7.2.1  Results -

In all irradiated systems investigated perchloroethylene reacted to 95%
completion.  However, the rate of reaction was substantially different
in each system investigated.  Hydrocarbons exerted an inhibiting effect
                                    255
-------
on the reaction rates.

Perchloroethylene in Ultra Zero Air at 50% R.H, -  In the photolysis of
perchloroethylene in ultra zero air at 50% relative humidity the compound
was 100% reacted in 1.5 - 2 hours,   Figure 92, whereas in the same system
plus 1 ppm hydrocarbon the time needed for total reaction of this com-
pound was considerably longer (Figure 93) ,

Perchloroethylene in Nitrogen -  Approximately 1 ppm was introduced in
the reaction chamber containing nitrogen.  Figure 94 clearly indicates
the accelerated decomposition of perchloroethylene with a peak concen-
tration of ozone of 1 pphm 03. Perchloroethylene reacted to completion
in this system in about 7.5 hours yielding phosgene as a decomposition
product.

Perchloroethylene in Air at 50% R.H. plus N02 and Hydrocarbon "A" - Inves-
tigation of this reaction mixture indicated that the time needed for com-
plete decomposition of perchloroethylene was between 23 and 31 hours (4
runs shown in Figures 95 - 98).

Perchloroethylene and NC>2 in Ultra Zero Air at 50% R.H. -  The time
needed for total reaction of perchloroethylene in this system was about
8 hours (Figure 84).

Dark Reactions in System Investigated -  In all systems investigated dark
reactions were conducted to verify that these compounds would not react
unless supplied with the energy of the provided light source.  This was
accomplished by preparing identical experimental mixtures and allowing
them to sit in the reaction chamber for the maximum time needed (indicated
by previous experimentation) to accomplish total decomposition of the
perchloroethylene if subjected to the light source. In all systems inves-
tigated concentrations of NO, NC>2, 0? and perchloroethylene were monitored
as a function of time.  The data indicated no dark reaction.

Ozone Dark Reaction -  In all experiments conducted it was observed that
at sometime in the course of the irradiation of the compound the ozone con-
centration would maximize followed by a sharp decrease in concentration.
This decrease in ozone concentration was always accompanied by a signifi-
cant acceleration in the rate of the perchloroethylene decomposition.  It
was therefore decided to investigate the possibility of an ozone attack
on the perchloroethylene.  This was accomplished by introducing a pre-
determined concentration of ozone  (maximum ozone concentration observed
in experimentation) in air in the reaction chamber, and by monitoring the
ozone concentration as a function of time to determine the time needed
for thermal decay of ozone in the system.  Approximately the same amount
of ozone was once again introduced into the reaction chamber with 1 ppm
perchloroethylene.  The ozone and perchloroethylene concentrations were
monitored as a function of time.  A decrease in the perchloroethylene
concentration and a decrease in the decay rate of ozone  (indicated by
the slope) would indicate an "Ozone Attack" on the perchloroethylene,
                                    256
-------
                                                  in
                                                  o'
                                                                           o
                                                                           c>
(£

<

O
DC
UJ
  OC


  Z>
  uj
3,1-
  a:

   ^r

  o
   CNJ
  O
                                                                                    CO
                                                                                    tr
                                                                                    X


                                                                                    UJ
                                                                                    z
                                                                                    o
                                                                                    tr
                                                                                    a:
                                        257
-------
                            00

                            O
                                    IMdd
CD

O


T
CVJ

d


T
cr
a:

O  <
OQ
o:  o
<  a:
o  LJ
o  M
a:
Q  <


-b

s  =

a!  5
o
CVJ
o
                                                       o
                                                       ro
                        O)
                        a:

                        x


                        UJ
                        z
                        O
                        ct:

                        (T
                           WHdd
                              258
-------
                   CO

                   d
INdd

  ^-
  d
o
d
                                                                  
-------
                              Wdd
o
CD
o:

o
o
cc
Q


*1

2 O
< a:
X
   z

e>
Q  Q

oc  uj
13  o:

a!  5
o
CVJ
o
(O
o
1 1 1 1
ro
O
1 - 1 '
O
c5
i
                            IMHdd
                           260
-------
 CVJ
o
< o
£ <
< a:
u t-
0-i
o: z>
Q ^
>. ^
   <
   a
O
            O
      o




IMHdd
                          261
-------
                                IMdd
                                 IO
                                 o
                                          o
                                          o
 CM
O

ii
< o
z tt:
° is
QQ M
2 <
o
>-
X
  Q
ST <
_J K
o tr
CM —
u
            ro

 L
o
                              o
                              to
                       I^IHdd
                          262
-------
     O
     DC
     UJ
     N
UJ
H   Q

5   2
,«   a:
Q_   O
     oo
          00
 CVJ
o
     ct:
     o

     x

     Q

     <
                                             IMHdd
                                                263
-------
and would possibly indicate one path of the mechanism of the perchloro-
ethylene decay.  The results,  however (Figures 99 and 100) did not indicate
this as a path in the mechanism involved in the atmospheric fate of per-
chloroethylene.

Phosgene as a Product -  In each system studied phosgene was identified
as a decomposition product.  However, the rate of appearance of the com-
pound varied depending on the particular system that was being investi-
gated.  Table 20 summarizes the systems investigated, and the phosgene
concentrations measured in each system as a function of irradiation time.

Phosgene as a Catalyst -  It was observed in the system of air plus per-
chloroethylene that once the phosgene was detectable by the gas chromato-
graph, perchloroethylene concentration decreased very rapidly.  Because
of this observation it was decided to investigate the catalytic effect
(if any) induced on this system by phosgene.  This was accomplished by
introducing the maximum concentration of phosgene observed as a result
of the reaction of perchloroethylene reaction in this system (0.8 ppm) ,
and irradiating it for a period of time equal to the longest time needed
for perchloroethylene total decomposition.  Phosgene and perchloro-
ethylene concentrations were monitored as function of irradiation time.
The results of this experiment, however, indicated that no catalytic
effect was exerted by the presence of the phosgene in the system, as
indicated by a lack of change in perchloroethylene concentration fol-
lowing 2 hours irradiation.

Formation of CC14 -  CC14 has been observed by us as a product during our
longer runs in the simulated tropospheric irradiation of synthetic mix-
tures of C2C14 in air.  In these and other long-term studies with other
compounds, N02 was replenished every 24 hours.  This was necessary because,
in our experimental arrangement, the half-life of N02 was only about 6
hours (See Figure 101).  Both COC12 and CC14 were identified by retention
data on two separate columns (5% SE30 and 30% didecyl phthalate for COC12,
and 5% SE30 and 10% DC200 for CC14) and by their electron attachment
properties( y>5>187  J,  The results of these experiments are presented
in Table 21.

During the irradiations, an unexpected peak was tentatively identified as
CHC12COC1 and traces of CHClg were also observed.  While quantitative
measurements of CCl^COCl were not feasible in these preliminary experi-
ments, it was identified as a product by the GC determination of its
isopropyl ester'1°4J>

7.2.2  Discussion -
The atmospheric fates of perchloroethylene were investigated in a variety
of systems.  In each system investigated, perchloroethylene under the
influence of the light source employed was chemically reactive.  The time
needed to accomplish a given decomposition of the perchloroethylene varied
significantly in repeated runs on the same system (see e.g. Figures 95 to


                                    264
-------













(U
4J
03
O"1
•H
-P
01
CU
J>
C
H

01
E
CU
4J
tn
w
0)
c
CU
rH

rC
•P
(U
0
O
rH
rC
U
H
(U
CM
o
CN
rH
42
03
EH
C
CU O
c -
CU -P
en 05
tn 5-t
O -P
42 C
O< CD
U
c
o
o
s
CU Pn
C QJ
CU
i— 1 »
r^< c
rC O
4-1 -H
CU -P
o ro
lr t._i
O -P
rH C
42 0)
V U
ii £*•*
CU O
04 CJ



O M
•H D
•P O
fd ffi

03 cu
5-1 -H
H EH








 IT)
 CU   W
•H   cn
42   O
 (0  -P
4J   (0
 U   g
 01   0
-P   !-l
 0)  ,C
T3   U
 I
 q
     01
 O   (0
 12!   (J>
 C
-H

 CU
 C
 01
    W
            in
rQ


 QJ
r-l

42
 re
                 (0
                 O
    +J
-P   03
 U   £
 
    K  =


e
CU
-P
to

en



CD
-P
03
Cn
-H
•P
tn
CU
^>
c
H
4J
CU
0

o
r-l
42
U
^
CU
CM
Dn

^
O
in

©

SH
•H
03
^J
Q)
o

o
rH

U
J^
-------
              c
              o
              •H
              CO  <*
          4->  M rH
          x:  cu o
          t^ > o
          •H  C
          CD  O  O
          £  U -P
                                n
o

CO
                                                   co





SH
•H
<
C
•H

^
rH
U
(N
O

UH
0
c
o
•H
4-1
(0
•rf
u
O
CO
CO
•H
'O
O
4J
O
CO
c
O
-H
4->
(0
!H
4-1 ^
C >
CD \
U >
c
O CT>
0 1
0
4-1 rH
U — '
D
T3
O
M
Ol









C
O
•H
4->
rc o;


•sj
r-H
O
U










r\
rH
8
o












*-*s
to
                                                              in
           rl  g  >1
           •O  -H  (0
                                o
                                o
                                o
                                        o
                                        o
                                        o
                                        o
                                        o
                                          *
                                        CO
                                        rH
                                                   (N
                                                    o
                                                    o
                                                    CT>
 o

 CO
4J
 u
 D
TD
 O
 >H
 O
•r-|
 (0
 S
           H
                CO
            C ^-"*
            O  CO
           -H rH
           4J  CU
            U  CO
            fO  CO
            (U  CD

            «  >
CO
CO
nJ
rH
O
Glass
Glass?
Teflon
Glass;
Teflon
Teflon
 0)
rH

#
 (0
            rH  C
            (0  O
            •H -H x-v
            4J -P  >
            •H  m x
            C  JH  >
            rH  O O
            U  C rH
             OJ O — '
            U  U
                           o
                           o
                           r-
                           CM
O
o
p~
(N
  O
  o
  r^
  
-------
                  Figure 99
           OZONE  DARK REACTIONS
             OZONE PLUS C2CL4
              DUPLICATE  RUNS
100 r—
 10
                 I
L
                 50            100
                    TIME (HRS)
                    150
                         >67
-------
                      Figure 100
                OZONE DARK REACTION;
            DETERMINATION OF  OZONE  DECAY
                   DUPLICATE  RUNS
  100 r-
                                       RUN* 2
x
0.
Q.
     0
50
       100
TIME (HRS)
                           268
-------
98).  Due to the highly irreproducible nature of this phenomenon, no
accurate explanation can be given at this time.  However, Dusoleil et
al.(-29^ observed the same phenomenon in a series of experiments in which
they investigated rate constants in gas phase photochlorination of per-
chloroethylene and pentachloroethylene.  Such erratic results they
attributed to "the time necessary for conditioning of the walls of the
reaction chamber"; accomplished by the occupation of the active sites
on its walls by "perhaps" polymeric chlorinated derivatives.  As a re-
sult of this phenomenon they discarded a number of their initial exper-
imental results which were erratic in terms of total time needed for
100% decomposition of the compounds of interest.

None of the experimental results obtained by us were discarded, since the
primary objective of the derived experimental scheme was to indicate the
fates of these compounds in a polluted atmosphere.  It was felt that the
variable nature of the decomposition kinetics were not as important to
an understanding of air pollution phenomenon as the observations that
C2C14 did decompose under simulated tropospheric conditions, and the
general behavior of the other reactants, intermediates and products.

Carbon Tetrachloride and Trichloroacetylchloride Formation -  A maximum
concentration of 72 ppb carbon tetrachloride was measured as a decom-
position product of the induced perchloroethylene chemical reactions.  This
was observed and measured in a mixture of air plus perchloroethylene
which had been subjected to the irradiating light source for 63 hours.
The same mixture was monitored for trichloroacetylchloride, and this com-
pound was positively  identified as a decomposition product by the method
previously explained.  CC14 concentrations continued to increase well
after all the C2C14 had reacted while the COC12 and CHC^COCl concen-
trations plateaued,  At the same time CC^COCl continued to react suggesting
its role as the CC14 precursor.  The overall reaction is probably initir t^ed
by photolysis of C2C14 followed by a chlorine sensitized photo-oxidation'"  '.

From Table 21 on the average, C2C14 photodecomposition leads in 7 days to
the formation by weight of about 8% CCl4 and 70 to 85% of phosgene.  Since
the present world-wide emissions of C2Cl^ can be estimated to be about 450
millions kg/yr.t1^)^ this conversion would result in an annual atmospheric
CC14 loading of 36 millions Kg/yr.

This source of CC14 alone can account, depending on the residence time, for
a significant fraction of the atmospheric CC14 budget.  In any consideration
of the CC14 budget, this source must be considered along with others such as
direct industrial emission and possibly methane/chlorine reactions^™.

Our laboratory simulation studies indicate that CC14 is tropospherically
stable (see Section 7.4.1 below).  Reactions such as CC14 + OH --> HOC1 +
CC13 or CC14 + 0 --> COC12 + C12  '     , are negligible under all tropo-
spheric conditions.  Given the relative inertness of CC14, another
possible precursor of ozone destroying stratospheric chlorine atomsd )
presents itself in the form of CC14 as a secondary anthropogenic pollutant.
                                   269
-------
It is significant too that a relatively innocuous material such as C2C14
(A.C.G.I.H.  T.L.V,  100 ppm) can decompose in the atmosphere to produce
highly toxic materials such as phosgene (Proposed A.C.G.I.H.  T.L.V. re-
vision 0.05 ppm).

Ozone Concentration -  In all systems studied, it was observed that the
ozone concentration would maximize after some given time of exposure of
the system to the light source.  The ozone concentration would then de-
crease with a simultaneous decrease in the concentration of perchloro-
ethylene in  the system and an increase in the rate of phosgene produc-
tion (seeFigure 98) .   In the system investigated in which hydrocarbon
"A" was incorporated it was observed that:

(a)  Ozone concentration increased at a slower rate than in any of the
systems investigated, and decreased beyond its maximum more slowly.

(b)  The reaction rate of perchloroethylene was substantially reduced.

(c)  The time needed for 96 to 100% decomposition of perchloroethylene
was substantially increased.

(d)  The observed ozone concentration was substantially greater than that
observed in any other system investigated.

Possible Reaction Mechanism for C2C14 -  There are no documentations of
simulated smog chamber studies performed on perchloroethylene.  However,
gas phase photochlorination studied performed using intermittent light
capable of inducing chemical reactions have been performed on mixtures
of perchloroethylene with Cl2 in airf^o) ^n which the following scheme
was proposed as the initiator in the observed chemical reactions of
perchloroethylene .

          Cl2 + hv     ----- > 2C1
          C2C14 + Cl   ----- >
          C2Cl5 + C12  ----- > C2C1& + Cl
          c2ci6 + ci   ----- > c2cig + ci2
          2C1 + M      ----- > C12 + M
          C2Clg + CL   ----- > C2C14 + C12
          2C2Cl5       ----- > C2C16 + C2C14

They also established the fact that reaction with impurities on the walls
or other entities (Cls, polymeric chlorinated derivatives needed to occupy
sites on the walls of the reaction chamber) were, within a highly experi-
mental precision, completely negligible.  Although the experimental scheme
studied by this investigator did not involve introduction of chlorine in
the reaction chamber, the writer proposes a chlorine sensitized oxidation
of perchloroethylene, initiated somewhat differently from that proposed
by Dusoleil et al . , but including some of his proposed paths.  The pro-
posed mechanism is as follows:
                                    270
-------
          C2C14          -_v_> C2CI^ + Cl
          Cl + C2C14     ----- > C2Cl5
          C2Cl5 + 02     ----- > C2C1502
          C2ci5o2        ----- > c2cij; + o2
          C2Clg + C2C1502 ----- > C2C1502C2C15
          C2C15°2 + C2Cl502---> C2C1502C2C15 +
          C2C1502 + C2Cl502 — -> 2C2C150' + 02
          C2C150-        ----- > CC13COC1 + Cl-
          c2ci5o-        ----- > coci2 + cci^ - >coci2 + ci
               + Cl-     ----- > CC14
As is clearly indicated by the proposed mechanism there is a time lag
necessary for the initiation and propagation of the radical -chlorine,
radical -oxygen and radical -radical species.  Figure 92 indicates a
time lag followed by a rapid decomposition of perchloroethylene.  In the
systems investigated in which hydrocarbon is introduced there is an
extensive initial time lag before perchloroethylene begins to react
chemically, and this is followed by a slow reaction rate.  This can be
explained by the fact that the very reactive olefin radicals not only
compete with the C2C14 for the C2Cl5 specie but also probably react
rapidly with the Cl chain carrier itself.  This proposed path would be
followed until the olefinic specie from the hydrocarbons has been totally
reacted. Then the perchloroethylene would be attacked by the Cl specie,
hence the observed extended time lag in the hydrocarbon system.  An
additional explanation could involve collisional de-excitation of the
C2C14* with olefin, resulting in a photosensitized dissociation of the
latter.

Step 8  in the proposed reaction scheme was substantiated by identifying
trichloroacetyl chloride with extended irradiation time of 24 hours.  It
was observed that the trichloroacetylchloride had been completely decom-
posed and the concentration of carbon tetrachloride had increased con-
siderably.  The overall reaction scheme may be presented to proceed as
follows by consecutive or side reactions:

          C2C14 ----> COC12 + CC14 + CC13COC1

Blank runs of all systems investigated produced very low NO, N02 and 0^
readings and no carbon tetrachloride or trichloroacetylchloride.

7.5  Methyl Iodide

7.5.1  Results -

Figure 102 shows the stability of methyl iodide in the presence of ozone
which decays thermally while the methyl iodide concentration remains the
same.
                                   271
-------
272
-------
 Concentracion (ppb)
(iLdd)
        273
-------
Figure 103 represents the photolysis of methyl iodide in a nitrogen
atmosphere.  The photolysis is apparently first order as the straight line
plot (Figure 104), of the concentration vs.  time shows.   The half-life of
the methyl iodide in this experiment was 6.5 hours.

The photolysis of methyl iodide in the presence of oxygen, as pointed out
in the literature^46,49,50,51,194 J should be faster than in its absence due
to the fact that methyl radicals react with  oxygen rather than recombine
with iodine to form methyl iodide.  However, the Teflon bags used for runs
were permeable to the oxygen in the room air and therefore the half-life
of 7.6 hours (Figures 105 and 106) for the photolysis of methyl iodide in
the presence of air and water is in disagreement  with neither the previous
value nor with other investigations.  Figure 85 shows the photolysis of
013! with the formation of NO and 63 in air  in presence of N02 and 50%
relative humidity, and Figure 107 shows the  first-order decay of CH^I in
this system.  Figure 108 shows the same measurements when 1 ppm of
hydrocarbon ("Fuel A") was present in addition.

7.3.2  Discussion -
From Figure 85 it is clear that the NC>2 half-life in air is much smaller
in presence of CH^I than in its absence (Figure 101).  With CH^I present,
the NC>2 half-life was less than 2 hours and the NO reached a peak of
0.175 ppm, whereas in the blank the maximum nitric oxide value was 0.120
ppm.  the initial concentrations of nitrogen dioxide were respectively
0.450 and 0.535 ppm.  Note that the nitric oxide remained at a steady-
state concentration in the blank but was consumed in the methyl iodide
irradiation.  From the literature&*• >^*' 1"5) nitric oxide has been shown
to be an extremely efficient scavenger for methyl radicals.  The half-
life of methyl iodide is a fast 3.6 hours (Figure 107) due to the
inhibition by nitric oxide of the back reaction reforming methyl iodide.
Hydrocarbons seem to negate the influence of nitric oxide on the reaction
(Figure 108).  The half-life of methyl iodide in this simulated urban air
was 5.5 hours.

The source of atmospheric methyl iodide has been postulated by Lovelock et
al.*-  •'to be the oceans.  Biological methylation of iodine by marine plants
and animals is a likely cog in the wheel of the iodine cycle.  Another
possible way the sea can be a source for methyl iodide is by methyl radi-
cals in the air reacting with sea salts.  To test this possibility, a mix-
ture of 12 ppm of potassium iodide and 1.0 ppm of acetone were irradiated
in the 72 liter pyrex reactor.  Almost immediately a four-fold increase
in methyl iodide over the unirradiated blank to a maximum of 1.4 ppm of
methyl iodide was observed.  This result agrees with experiments of Pitts
and Blacet  ( 195) .

7.4  Carbon Tetrachloride

7.4.1  Results -
 Figure 83  shows the reaction of carbon tetrachloride with nitrogen oxides,


                                   274
-------
(qdd)
          275
-------
                              -   •„ Nitroeen  on semi-log paper
4 Figure 104 - CH3I Photolysxs in Nitrogen,
                          4      .   6
                    Time Irradiated (Hrs.)
                                  276
-------
-------
10 \
  LV
 *
    •  \  Fieure 106 - CH3I Photolysis  in Air with 50% R.H. on
Figure
                       semi-log paper
                                       CH,I
                                    278
-------
Figure 107 - CH3I  *  N02  in  air with 50% R.H. on semi-log paper
                          12





                            279
16  Time Irradiated (Hrs.)
-------
(u>dd)  ucnriEaauaoucrj  o tueajouj
         280
-------
ozone, atomic oxygen and simulated tropospheric sunlight in a Mylar bag.
The compound remained stable for more than 200 hours.  The chamber was
replenished daily with nitrogen dioxide to bring the chamber to a 0.5
ppm concentration providing a constant supply of reactive constituents
for attacking the halocarbon.

Figure 109 depicts the stability of carbon tetrachloride from the attacks
of free radical hydrocarbons as well as ozone, atomic oxygen and nitrogen
oxides.  Here too, nitrogen dioxide was replenished daily.

Having established the tropospheric stability of CCl^, its possible
stratospheric reactivity was investigated.  Figure 90 includes its
decay under the influence of U.V. irradiation in ppb mixture in air.
Its half-life under our conditions of 5.5 minutes corresponds to a
minimum half-life in the stratosphere of 37 hours.

7.4.2  Discussion -

From the data presented above it can be inferred that carbon tetrachloride
will not decompose in the troposphere.  It is clear, however, that €014
will play a role similar to that ascribed to CCljF and CC12F2 as precur-
sors of chlorine atoms potentially destructive to stratospheric ozone.

7.5  1:1:1 Trichloroethylene

7.5.1  Results -

Figure 109 shows the reaction of 1:1:l-trichloroethane with nitrogen
oxides, ozone, atomic oxygen, free radicals and simulated tropospheric
sunlight in a Mylar bag.  The compound remained stable for more than
200 hours.  The chamber was replenished daily with nitrogen dioxide to
bring the chamber to a 0.5 ppm concentration, providing a constant
supply of reactive constituents for attacking the halocarbon.

7.5.2  Discussion -
From these systems, it can be inferred that methyl chloroform will not
decompose in the troposphere.  We have not tested its stability to strato-
spheric conditions.

7.6  Trichloroethylene

7.6.1  Results -

Figure 110 illustrates the stability of T.C.E. to thermal attack by
ozone.  Figure 111 shows the effect of irradiating this compound with si-
mulated tropospheric sunlight in nitrogen.  The effect of the presence of
air and 50% relative humidity are shown in Figure 112.  With the addition
of N02 to the reaction mixture the results shown in Figure 113 were
obtained.  Figure  114 shows the results when both N02 and hydrocarbon
                                   281
-------
M
o)
£>
  rt
5-0
^-t "O
12
 u c
 u a
 o
 fH

 O
                            O
                            O
                                                O
                                                o
                                      \t\
            (qdd)


            282
-------
                                         Figure 110


                                   TRfCHLOROETHYLENE +

                                          dark reaction
 100
                                                        TCE
  80
•  60
o
u
  20
                     20
    40

time  hrs
                                                     60
                             283
-------
  M
  CO
 JO

  q
  o
 r—(
 <4-
  0)
 c
 c
 (Nl

  rt

  C
 rt
 •H
 -a
 c
 • H
 a;
 c
 X
X
 (D
 O
 o

E-
 i
 3
•M
u_
 cn
 V.
J-.
                                                                                                                    LU
                                                        284
-------
                                       qdd   auoo
                                                                        £




                                                                        01
flC  .=
      o
      e
                                uiqdd    ONOD
                                285
-------
qdd  NOI1VU1N3DNOO
    286
-------
              «»dd  ONOO
uiijdd
 287
-------
("Fuel A") were present in the irradiation mixture.

7.6.2  Discussion -

T.C.E, is clearly stable to direct 03 attack - the ozone half-life was
unchanged whether T.C.E. was present or absent, and no discernable
decrease in initial T.C.E. concentration was apparent after almost 60
hours of exposure to 63.

In the system where N02 was employed, it was noticed that the time
required for 95% decomposition was much longer than in systems where
trichloroethylene was reacted without the nitrogen dioxide present.  This
same phenomenon was observed by Wilson(21) when she studied the photo-
reactivity of trichloroethylene.  It was noted by her that if the N02
concentration is several times that of trichloroethylene, the reaction
was completely inhibited and that the rate of decomposition is quite
dependent on the T.C.E./N02 ratio.  As the ratio decreased, she noted
that all the measures of photoreactivity also decreased.

In the system where both nitrogen oxide and Fuel A were introduced, it
was noted that the hydrocarbon further inhibited the reaction.  The
occurrence of a competitive reaction seems to be a good possibility.  The
synergistic effects of one hydrocarbon to another are extremely hard to
evaluate, and since this report is not primarily concerned with reaction
kinetics the possibilities were not thoroughly investigated.

In all the systems investigated, phosgene was the major decomposition
product observed.  By doing a chlorine balance it can be seen that at
the point of 95% decomposition approximately 30% of the budget is converted
to phosgene.  Depending on the system studied the rate of formation of
phosgene varied;the quicker the trichloroethylene dissociated, the more
rapid the formation of phosgene.  A proposed mechanism for the formation
of phosgene and the other decomposition products which is consistent with
the present observations is presented later in this section.

Chloroform was noted to form in all systems where light was employed, the
maximum concentrations observed varying from 8-15 ppb depending on the
system investigated.  Again, the rate of formation was dependent on the
decomposition rate of T.C.E.  Other products identified were dichloro-
acetyl chloride and HC1.  Both of these products were identified quali-
tatively but the concentrations could not be quantified due to limita-
tions of procedures employed.  In order to account for these products a
chlorination reaction is suspected.

The formation of ozone occurred in all the systems investigated where a
light source was employed.  After the ozone concentration reached its
peak a steady decay took place.  It was also noted that following the
peak the decomposition of trichloroethylene accelerated.  The time for
the peak concentration to occur in identical systems varied considerably
as well as the magnitude of the peak concentrations observed.
                                    288
-------
The following reaction mechanism is proposed in order to account for the
observed formation of the products mentioned.  The mechanism involves a
chlorine-sensitized photo-oxidation of trichloroethylene.  Huybrechts et
al. *-   ' did work on the chlorine photosensitized oxidation of trichloro-
ethylene but in their case CL2 was added as a primary reactant,   The
mechanism they proposed was discussed earlier in this report.  This
mechanism could not account for the results observed in this study but
some of the reactions are included.  The proposed mechanism for the
present study is as follows:

     i)   c2HCi3         -----> c2Hci2 + cr
     2)   Cl- + C2HC13   	> C2HC14-
     3)   C2HC14 + 02    	> C2HC1402'
     4)   C2HC14' + C2HCl402--> C2HC1402C2HC14
     5)   C2HC1402- + C2HCl402---> 2C2HC140' + 02
     6)   C2HC140-       	> CHC1COC12 + Cl-
     7)   C2HC140-       	> COC12 + CHC12'
     8)   CC13-CHC10-    	> CC13' + HC1 + CO
     9)   CC13' + %}2    	> COC12 + Cl-
    10)   CHC12' + Cl-   	> CHC13

This mechanism accounts for the products and the time lags observed in
the various systems investigated.  Time is required for the initial pro-
pagation of chlorine radicals, oxygen radicals and radical-radical species.
The time lag varied significantly from one system to another due to the
presence of N02 and fuel competing for the radicals being formed.  The
time lag in the systems with nitrogen dioxide is substantially longer than
in the systems not incorporating N02.  This is suspected to be due to
nitrogen dioxide competing for Cl•  radical thereby increasing the time
required for trichloroethylene decomposition and product formation.  Evi-
dence to this occurring is provided when the chlorine budgets in runs
incorporating N02 and those not incorporating N02 are compared.   The products
observed in the runs not incorporating N02 account for approximately 41%
of the chlorine initially present,  where in the systems with N02 added the
products observed only account for about 24% of the chlorine.  A possible
competitive reaction follows:

          Cl + N02 + M 	> C1N02 + M
          C1N02 + 0    	> C1NO + 02

If this reaction occurs it can account for the differences in the chlorine
budgets.  Further evidence of this competition occurring is provided by
Figures 113 and 114.  These figures demonstrate that as the N02 concentration
drops off the inhibition becomes less severe and the trichloroethylene
decomposes at a much more rapid rate.  Similarly, the mechanism can account
for the increased time lag when Fuel A is added to the system.  In this
case again a competition for free radicals is expected.  The reactive
                                    289
-------
olefin species provided by the hydrocarbon competes with the trichloro-
ethylene for the 02^1^' species as well as the Cl' chain carrier.  Once
the olefinic species is reacted, then the photo-dissociation of trichloro-
ethylene proceeds at a much more rapid rate.

7.7  Ethylene Dichloride

7.7.1  Results -
Figure 115 shows the stability of dichloroethane to simulated tropospheric
conditions.  No decomposition was observed over a period of almost 400
hours.

7.7.2  Discussion -
Ethylene dichoride is a saturated alkane, held together only by sigma
bonds. Extremely high energy of short wavelengths are necessary to pro-
mote the electrons.

In order for any compound to react photochemically, it must be capable of
absorbing light in the range of wavelengths employed.  In this study the
wavelengths of light employed were predominantly in the visible region
of the spectra.  In order to determine if the compound absorbs in the
region the spectrum covering the UV and visible portions was examined,
and it was found that -it was transparent to wavelengths greater than
2900A.  Therefore, light present in the chamber or in the troposphere
could not cause the compound to react.

It is also evident from Figure 115 that dichloroethylene is also very
unreactive towards reactive photochemical intermediates.  Tropospheric
reactions are thus unlikely to be a major sink for the compound.

7.8  Vinyl chloride

All experiments were performed using 200 liter Teflon bags filled as
previously described (Section 4.2.4).  Vinyl chloride initially at
F*l - 10 ppm was irradiated with simulated sunlight under the following
conditions:

a)   in ultra zero air at 50% relative humiditiy
b)   in dry nitrogen
c)   in ultra zero air at 50% relative humidity, with N02 present,
       initially at 0.2 to 6 ppm
d)   as for (c), with hydrocarbon present.

The dark reaction between vinyl chloride and ozone (~5 ppm) in ultra zero
air at 50% relative humidity was also studied.

7.8.1  Results and Discussion -

The effects of irradiating vinyl chloride in air at 50% relative humidity


                                    290
-------
291
-------
are shown in Figure 116.  For comparative purposes the corresponding
data for a nitrogen atmopshere are also shown.   It can be seen that in
both cases the removal of vinyl chloride is rather slow, with only a
slightly greater rate in presence of oxygen.  The removal rates cor-
respond to half-lives of approximately 17 hours in air and 30 hours in
N2.

Several experimental runs were performed in which N02 was present in the
vinyl chloride/air mixtures.  Results of one such run are shown in
Figure 117.   The initial vinyl chloride concentrations were varied between
1 and 10 ppm, and the vinyl chloride:N02 ratios were in the range 1.4 to
5.3.  No significant differences were observed in the time for the vinyl
chloride concentration to fall by a factor of two - the average time was
3±0.6 hours.  Ozone usually peaked at about this time.  The other reaction
products identified in the V.C./N02 runs were NO, formaldehyde and HC1.  NO
was usually very low, peaking soon after the start of the irradiation, and
falling rapidly to undetectable levels within about 3 hours.  Formaldehyde
slowly built up over this period to 1 or 2 ppm.  HC1 was not quantitatively
determined.

The effect of adding hydrocarbon to the V.C./N02/air system is shown in
Figure 118.   Though the N02/V.C. ratio was very low, the vinyl chloride
still disappeared at about the usual rate.  NO disappeared very rapidly,
accompanied by a rapid rise in Oj, and a steady build-up of formaldehyde.

Vinyl chloride in air reacts rapidly with ozone in the absence of light,
as shown in Figure  119.  Formaldehyde and HC1 are products.

It is clear that in presence of N02, 03 or hydrocarbon, vinyl chloride is
more photochemically reactive, than in their absence.  In experiments
where the hydrocarbon fuel was added, NO disappearance was especially
rapid, confirming that the hydrocarbon supplies significant amounts of
reactive species such as radicals.  We might have  expected  that hydro-
carbon would also protect vinyl chloride  by itself competing  for the
available reactive  species.   This  evidently did not occur  in  our systems
to any great extent.   Possibly the additional  radicals made available by
the presence of  the hydrocarbon counterbalanced this effect.

In all runs  containing N02,  formaldehyde  was a product.  Approximately
equal  amounts  of HC1  were  formed  simultaneously.   Gay et al.1-78  ' have
also observed  HC1  from photooxidation of  vinyl chloride.   In  their
work,  about  50%  more HC1 than formaldehyde  was produced.   They also report
formyl chloride, which decomposes  rapidly to CO  and HC1.   Sanhueza and
Heicklen^99 J.  observed HC1  formation  from both Cl-atom and 0(3P)-
initiated oxidation of vinyl chloride.  They found no evidence for
formyl chloride  formation  in the  former case,  but  observed it, as well
as CO, HC1  and formic acid,  in the latter case.  Apparently HC1  is both
a primary and  a  secondary  product.

The major product  observed in our experiments  was  ozone.   The peak 0^
values correlated strongly with the initial levels of N02  present.   When
                                    292
-------
                  K)
VINYL CHLORIDE,  P.P.M.
w       *»      in       ci
            -H :
           -'i-
                      :,;-:-£-
                      _;_ , ..,_ ..;
                       I  :
                       -1	
H/
                            -i •F-htir
                               o;
                                      .
                                                      00'
                   -0
            -j....
                                                         in
                                           - -JMI
                                             ••*---
                                                                 =r:~:Q.-r-
                                                                  ::'-n
                       -4iH'
^s

                                          -> -..
                                         ^•^9
       '-hH-
                              j_i~:
a
§
g

                                                                  FSI1
                                                                   :.»T

                                                        —gr^

                                 ^15:

                                     .-.:) .:
                                                                  _W-
                                                                  : O
                                                     -I".
 OL
                                     If
                                     f
                           iz
                                 293
-------
P.P.M.
294
-------
P.P.M
                                 10
    295
-------
296
-------
hydrocarbon was present, initial ozone production was particularly rapid,
peaking in about 2 hours, as compared with 3-5 hours for runs where hydro-
carbon was absent.  This is as expected, as 03 build-up is partly due to
the oxidation of NO to N02 by organic radicals, followed by N02 photo-
lysis.  Ozone attack on vinyl chloride is certainly a major factor in the
removal of V.C. in our experiments, as may be seen by the "dark" reaction
(Figure 119),  Possibly an intermediate cyclic ozonide is formed, which
can break up into either formyl chloride, CO and H20 or formaldehyde, C02
and HC1.  The low levels of HC1 observed, however, imply that other halo-
genated reaction products, not measured in this study must also be formed.

Vinyl chloride would appear to be quite reactive photochemically in
presence of N02 and hydrocarbons, and would presumably be fully photo-
decomposed in the troposphere, though near emission sources it might per-
sist under adverse meteorological conditions.

7.9  Dichloromethane
Simulated tropospheric irradiation for up to 16 hours of dichloromethane
in various mixtures in nitrogen, ultra-zero air, N02 and hydrocarbon fuel
resulted in no significant decrease in dichloromethane concentration.  This
compound is evidently quite stable under these conditions.   This finding
agrees with those of others, such as Billing et al.f^^), McConnell et al.
(196) and Wilson and DoyleC197).

7.10 PCB's
The following laboratory investigation was designed:  (a) to simulate some
important physical and chemical parameters characteristic of both clean
air and polluted air and (b) to study the effect of those parameters on
the rates of disappearance and products formed of a selected chlorinated
biphenyl.

Commercially prepared mixtures of PCB's as mentioned previously are com-
plex mixtures of between 50 and 100 isomers.  The use of these mixtures
in photochemical studies poses a nightmare in analyses and interpretation
of product formation.  Therefore, we deemed it advantageous to study a
selected isomer.  It was estimated that the results of such a study would
yield mechanistically interpretable products.

Ortho-chlorobiphenyl (OCB) was chosen since:  (a) it is present in commer-
cial PCB formulations, (b) it is volatile and (c) it exhibits an ultra-
violet absorption similar to other PCB isomers (Figure 3).  From a prac-
tical standpoint, the isomer could be obtained from commercial sources in
a very pure form (Analabs, Inc., North Haven, Connecticut).

7.10.1  Results and Discussion -
All experiments were performed in 250 liter FEP Teflon bags, the details
of which have been described  (Section 4,1.1).  All experiments employed
                                    297
-------
50% relative humidity conditions.

Stability of OCB in the Absence of Ultraviolet Radiation -  As indicated
by Figure 120 less than 12% of OCB is lost from the gas phase over a 24
hour period.  The 250 liter sample of 1.7 ppm OCB declined to 1.5 ppm in
the absence of ultraviolet radiation.  This was found to represent an
unacceptable loss in the light of the experimental design.

Effect of Ultraviolet Wavelength Intensity on Rate of OCB Destruction -
Since OCB absorbs ultraviolet radiation coincident with incident tropo-
spheric radiation, the effect of variation in intensity of those wave-
lengths on OCB was studied in an "inert" atmosphere.  Irradiations were
carried out in nitrogen at 50% relative humidity.  This was considered
as an inert photochemical environment since neither N2 or H20 absorb
energy in the range utilized.  In addition, both require energies greater
than could be supplied by any energy transfer processes to rupture their
bondsC 42 )_  Traces of oxygen present (primarily permeation through Teflon
film) will weakly absorb some long wavelengths (in the visible range) but
represent little potential to effect chemical change in OCB.  The bond
energies of N2, H20, and 02 are 226, 119 and 117 Real/mole respectively
which are higher than the highest energy found in the simulated tropo-
spheric ultraviolet radiation utilized G~99 Real/mole).  However, the
carbon-chlorine bond, which possesses a strength of 58-97 Real/mole depen-
ding on the carbon's other bonds, does have the potential to rupture under
these conditions.  The other bonds in the biphenyl structure are of energy
beyond the tropospheric  cut off.

The first experiment utilized radiation which roughly represents the
quality of the tropospheric ultraviolet spectrum.  It is difficult to
determine the absolute intensity of this range without elaborate and
expensive instrumentation.

The result of these runs are displayed graphically in Figures 121  and 122
respectively as concentration and log concentration OCB as a function of
irradiation time.  A 59% loss of the starting concentration was observed.

The second experiment involved changing the spectral distribution of the
incident radiation.  By increasing the lamp distribution from 6 to 24 sun-
lamps, the intensity of the 310 nanometer band is effectively quandrupled
since the blacklamps do not remit in this range.

The results of three runs are displayed graphically in Figures 123 and
124 respectively as concentration and log concentration OCB as a function
of irradiation time.  A 97% loss of the starting concentration was ob-
served.

If it  is assumed that OCB absorbs radiation in the 310 nanometer range
resulting  in chemical change,

     1)    OCB + hv	> OCB*
                                    298
-------
                            FIGURE 120
                    ^i-iE^YL STABILITY IN 250 LITER TEFLON  EAOS


            IN TliE ABSENCE OF  ULTRAVIOLET RADIATION.
£
a.
M
PQ
C
e:
o
o

o
      2.0
      1.5
1.0
     0.5
     0.0
          0     200      1:00     ?00     800     1000     1200
                             299
-------
                           FIGURE 121




     GRTHO-CHIOPOBIPHZNYL IS NITROGEN IRRADIATED WITH



       SIMULATED TROPOSPKERIC RADIATION (LINEAR PLOT).
    2.0
Pu
Pu
>H
§


g
 i
o
K
C
    0.0
200
600     800



    (VI:JUTES)
1000
                                                       1200
                             300
-------
                            FIGURE 122



      ORTHO-CHLOR03IPHENYL II* NITROGEN IRRADIATED WITH SIMULATED



     TROPOSPKERIC  RADIATION CLOG CONCENTRATION VS. TTMT?.) _
   10.0
    1.0
2;

a
»—«
A,
M
PQ
o
K
O
o


c
    0.1
  0.01
              200
                            RUN 1
                       A


                       n
                            PUN 2
                            PUS 3
                              600     800     1000     1200



                            TPTE (''INUTES)
                             301
-------
                                  FIGURE 125
             OPTHO-CHLOR03IPHENYL IN NITROGEN IRRADIATED WITH FOURFOLD
                310 NANOMETER INTENSITY SOURCE (LINEAR PLOT).
          2.0
          0.0
              0      200      LOO      600      800     1000    1200
                                 1T*E  (MINUTES)
-r  -V
302
-------
                         FIGURE 124


      OR7HO-CHLOROBIPHENYL IN NITROGEN IRRADIATED WITH FOURFOLD


310 :;ANO:*ETEP INTENSITY SOURCE (LOG CONCENTRATION vs. TIME).
   10.0
 g
 w
 §


 g
 o

 c
 o
 s
   0.01
200     HOO     600     600    1000



               TIME (MINUTES)
                                                      1200
                            so:
-------
the rate of disappearance of OCB is expressed as la the rate of absorption
of OCB.  la is equal to the product of the molar extinction coefficient e,
the integrated light intensity I., the pathlength L, and the concentration
of OCB.  The rate of disappearance of OCB is hence, dependent on the con-
centration of excited OCB*.

If it is assumed that the rate of absorption assuming thermal deactivation
and emission processes are small or constant, then the rate of disappear-
ance of OCB is :

     2)   d(OCB)  * I   = el (L(OCB)
          ~dt~
if we rearrange and integrate to the linear form, the effect of I. can be
evaluated.
     3)   OCBt


        ') (OCB)


     4)

where t0 = 0.

The rate of 2) is expressed as d the quantum yield of disappearance.

     5)   log (OCB) = -tI0L
                      -2303 t + log (OCB)Q

Evaluation of Figures 124 and 122 in terms of 5) for the rate of disappear-
ance eI0L illustrates a rate of 0.948 x 10"^ sec'-'- for the tropospherically
balanced irradiation versus a rate of 4.48 x 10"^ sec~l for the increased
310 nanometer band.  Thus a four-fold increase in the 310 nanometer inten-
sity produces a four-fold increase in rate of OCB disappearance.

Effect of Reduced Oxygen -  The effect of oxygen in the photodegradation
of OCB was explored by irradiating OCB in air and nitrogen.  The nitro-
gen irradiation was viewed as a reduced oxygen experiment since the
initial nitrogen can have up to 20 ppm oxygen and oxygen from room air
permeates through the bag material at a substantial rate.  The concen-
tration and log concentration of OCB as a function of irradiation time
are plotted in Figures 125 and 126.

The data indicate a 75% decay of the OCB in air as opposed to a 59% delay
in nitrogen.  Again assuming first order kinetics, the semilog plots
yield rates of 2.01 x 10'*' sec'l in air vs. 0.95 x 10"^ sec'l in nitrogen.

The results support the hypothesis that OCB is degrading through direct
                                   304
-------
                             FIGURE 125


      , ORTHO-CHLOROBIPHENYL  IH AIR IRRADIATED WITH SIMULATED


              TPOPOSPL'EPIC RADIATION (LINEAR PLOT).
£
FU
Pk
M
FQ
O
 ?
o

I
o
    C.
    0.0
               200
600     800     1000


Tl'ffi (^INUTES)
1200
                               305
-------
                           FIGURE 126
      ORTHO-CHLOROBIPKEHYL IH AIR IRRADIATED WITH SIMULATED
     rROPOSPHERlC RADIATION (LOG CONCENTRATION VS. TIME).
 10.0
  1.0
M
O
|
O
O
EH
O
eO.l
0,01
200
                     o   ?u:; i
                     A   ?-JIJ 2
                     D   ?T^ 3
                            60Q     800     1000    1200
                           TIME (MINUTES)
                            306
-------
photodissociation.  The slower rate of decay in nitrogen is expected since
the unreactive nitrogen functions as a collisional deactivating body for
the excited OCB*.   Collisional deactivation returns the electronically
excited OCB* to its undissociated ground state before photodissociation
can occur.

Oxygen also can function as collisional energy absorber.  However, the
photodissociated OCB would probably react readily with molecular oxygen.
Thus, in air the biphenyl radical reacts with oxygen to form a peroxybi-
phenyl radical.   In the nitrogen environment the lack of reactive oxygen
also makes more likely the recombination of the biphenyl radical and
atomic chlorines thus producing the observed slower rate of decay.

Chlorinated Products -  On the assumption that atomic chlorine is generated
upon the rupture of the weak carbon-chlorine bond, it is believed that the
photodissociated chlorine produces hydrogen chloride under tropospheric
conditions.  Wofsy and McElroy in a tropospheric/stratospheric model cal-
culated that kinetic and thermodynamic considerations favor the formation
of HC1 in the troposphere<"198) _  Chlorine dioxide (C102), which is probably
formed readily from the reaction of free chlorine and the abundant mole-
cular oxygen, readily photodissociates under tropospheric conditions.
Other species less likely formed considering the unlikely reaction of two
chlorine atoms are chlorine monoxide (C120) and free chlorine (Cl2).  These
would also be readily photodissociated under tropospheric conditions(178,
199).  Hydrogen chloride, however, will be readily formed in the presence
of molecular or atomic hydrogen.  Hydrogen chloride will not dissociate
under the influence of tropospheric radiation and is stable in the chemical
dynamics of troposphere(198).   In the real troposphere HC1 probably reacts
with ammonia to form ammonium chloride.  However, in the purified air used,
it was assumed that ammonia was not present (<10 ppb based on NOX measure-
ments) and therefore the chlorine was analyzed as soluble chloride ion
(Cl~) along with hydrogen ion (H+).

Figures 127, 128 and 129 illustrate the corporation of H+ and Cl~ concen-
trations (expressed as micrograms M^) as a function of irradiation time.
Perhaps more revealing is the production of H+ and Cl" normalized against
the OCB lost.  Assuming that all OCB lost forms equimolar concentrations
of HC1 then a plot of the data should show a constant ratio (product
observed to product calculated from OCB loss) of 1.0.  Figures 130, 131
and 132 illustrate the results for the chlorine yields.  Figures 133, 134
and 135 similarly demonstrate the corresponding hydrogen ion yield.

Although a constant 1.0 ratio was not obtained, a few observations are in
order.  The scatter observed in the earlier part of the irradiations is
in general much greater than the final data points.  This is not unexpected
since the precision of the potentiometric method at low ion concentrations
is poor.  Additionally, changes in OCB concentration at high concentrations
are more difficult to detect due to the non-linearity of the electron cap-
ture detector.
                                     307
-------
02




8

O
M
                          FIGURE 127



      SOLUBLE CHLORIDE AND HYDROGEN ION PRODUCTION IN THE



   NITROGEN/FOURFOLD 310 NANOMETER INTENSITY IRRADIATION  (LOG



                  CONCENTRATION VS. TIME).
   '10-
    10
    10  —
                   O  RUN 1: CHLORIDE ION



                   A  RUN 2: CHLORIDE ION



                   Q  RUN 3: CHLORIDE ION
                                 O  ?U!i I; HYI^OGEN ION



                                A  PUN 2: HYDROGEN ION



                                    PUN 3: HYDROGEN ION
200
600
POO
                                             1000
1200
                            TIME ("INUTES)
                             308
-------
                          FIGURE 128


     SOLUBLE CHLORIDE AND HYDROGEN ION PRODUCTION  IN  THE


 NITROGEN/SIMUL/TED TROPOSPHERIC IRRADIATION  (LOG  CONCENTRATION


                         VS. TIME).
oo
 s

 CO
 K
 O
 M
     105
     10
10-
                O  RUN 1: CHLORIDE ION


                A  RUN 2: CHLORIDE ION


                D  RUN 3: CHLORIDE ION
                •   RUN 1: HYDROGEN ION


                A   RUN 2: HYDROGEN ION


                B   RUN 3: HYDROGEN ION
         0     200     1)00     600     800     1000    1200


                              TIME (MINUTES)
                           309
-------
                        FIGURE  129




  SOLUBLE  CHLORIDE AND HYDROGEN ION PRODUCTION IN THE AIR/




SIMULATED TROPOSPHZRIC IRRADIATION  (LOG CONCENTRATION VS.  TIME).
           O   RUN  1:  CHLORIDE ION




                RUN  2:  CHLORIDE ION
            U  RUN  3:  CHLORIDE ION
                         o  RUN i: HYiPOGi::; ION
                        A  RUN 2: HYDPOGSN ION




                         a  RUN 3: HYDP01EN ION
          200
                                                 1200
                           310
-------
                              FIGURE 150


       CHLORIDE  lONrORTHO-CHLOROBIPHEHYL LOSS VS.  TIME IN THE


  3ITPO-3KJ/FOURFOLD  310 UANQ'-ETER INTENSITY IRRADIATION.
     2.0
co
CO
o
PH
M
pq
o
PC
o
i-3
33
O

O
cc
o
CO
>
o
M
I
K
e
o
M
(X
Q
t-^
W
O
1.5
1.0
„•   0.5
    0.0
                O   RUN 1


                A   RUN 2


                D   HUN 3
                                1
200    100
                                       800    1000


                             TIME (MIliUTES)
                          600
                          9
1200
                                311
-------
                            FIGURE 151


       CHLORIDE lOiliOPTHO-CHLOROBIPHENYL LOSS  VS.  TDffi IN THE


UITB03M/SIMULATED TROPOSPHERIC IRRADIATION.
     2.0
CQ
CO
PL,
M
pq
o
H

§
C.O
>

o
M
K
O
     1.5
1.0
0.5'
     0.0
               D
               RUN  1


               RUN  2


               RUN  3
               200
                   Hoo
600
Soo
1000
1200
                              312
-------
                            FIGURE 152



       CHLORIDE  ION:ORTHO-CHLOR03IPHEKYL LOSS  VS.  TIME IN THE AIR/



              SI14ULATED 730POSPHERIC IRRADIATION.
to

s
PH
s
A
as
E3
q


I

§
o
o
M
M
K

s
t^
O
                O    RUN  1



                A    RUN  2



                D    RUN  3
200     ^400     600



              TI'«E '
1000
                                                       1200
                               313
-------
                             FIGURE 155



        SOLUBLE  EYDROGEH  ION FOR'ttTIOI?:ORTHO-CELOPOBIPKENYL LOSS



 VS. TIME  IJ THE NITROGEN /FOURFOLD 310 NANOMETER INTENSITY IRRADIATION.
CO
to
a.
M
CQ
O
K
O


O
K
O
CO


§
M

13
g

g
a
c
O
O
co
    2.0
1.5
1.0
    0.5
    0.0
           O-  RUN 1



           A  HUN 2



           D • RUN 3
              _1
              200
                         600
800
1000   1200
                            TIME  (MINUTES)
                              314
-------
                              FIGURE  134


         SOLUBLE HYDROSEN ION :ORTHO-CHLOROBIPHENYL LOSS VS.  TIME IN


  NITROGEN/SriULATED TROPOSPEERIC IRRADIATION.
    2.0
CO
M
cq
o
K
 I
o
o

 •
CO
o
M
PL,
O
M
n
w
I-P
cq
O
CO
1.5
    1.0
    0.5
    0.0
                  RUN  1


                  RUN  2


                  RUN  3
               200    1^00      600     800     1000    1200


                             TIME (MINUTES)
                               315
-------
                            FIGURE 155



     SOLUBLE  HYDROGEN ION:ORTHO-CHLOROBIPHENYL LOSS VS. TIME IN


         THE  AIR/SIMULATED TROPOSPHERIC IRRADIATION.
    u.o
CO
w
(X,
M
pq
o
K
W
O
 I
o

EH

g
to
I
o
o
M
O
LO
3.0
    2.0
    1.0
    0.0
                                   O  RUN 1


                                   A  RUN 2


                                   D  RUN 3
               200     HOO      600     800   1000


                             TIME( MINUTES)
                                                 1200
                              316
-------
The final data points, however, are in good agreement for H+ and Cl~.  Due
to the poor reproducibility of the earlier data points, however, it is
difficult to discern any distinct trends between experiments.  In general,
OCB loss yields a quantitative conversion (50-100%) to HC1.

Irradiations of OCB in the presence of nitrogen dioxide were made but are
not included here because instrument problems rendered OCB analysis poor.
However, it should be noted that phosgene, COC12, was measured at ppb
levels after about 17 hours of irradiation.   Phosgene, although not
measured in the experiments presented here,  is expected to be produced in
air irradiations without N02.

Phosgene probably accounts for a very small  (less than 1%) fraction of the
chlorinated product yield.  It is expected that it is formed by the reaction
of atomic chlorine with atmospheric carbon monoxide.

     6)   Cl + CO	> COC1
     T)   COC1 + Cl -—> COC12

It is not surprising that phosgene is produced in such small yields since
its formation required the collision of CIO and Cl which are both present
at low concentrations.  This contrasts with the formation of HC1 which
requires the collision of one chlorine atom with one available hydrogen.
The available hydrogen could be from molecular hydrogen present at 0.5 or
from hydrogen on other PCB molecules.

Oxygenated Products -  Since a review of the literature revealed that the
photodissociation of aromatic halides in an oxygen environment generally
produces phenol, aldehydes, and polymers analyses for phenolics and alde-
hydes were performed 0-'^ ) _

Although a detailed aldehydes and phenolics analysis by gas chromatography
was desired, this proved impractical.  Phenolics are difficult to separate
by gas unless first derivatized.  Higher molecular weight aldehydes like-
wise are difficult to separate without decomposition and the low molecular
weight aldehydes suffer low sensitivity with flame ionization detectors.
Analyses for phenolics and aldehydes were thus performed by wet chemical
methods.  Unfortunately, these techniques are non-specific and in the
case of the aldehydes methods, insensitive.

In the irradiations made in nitrogen at the fourfold 310 nanometer inten-
sity, an average of 1.06 ppm aldehydes (at HCHO) remained at the end of
the 24 hour irradiation.  The phenolics peaked at 3 ppb in the first 300
minutes and were undetectable at the end of the irradiation (see Figure
136).

In the nitrogen irradiations made with the tropospherically balanced lamp
array  (1/4 the previous 310 nanometer intensity), aldehydes averaged
0.45 ppm (as HCHO) at the end of the irradiations.  The phenolics again
peaked at around 3 ppb but did not reach its maximum until 700 minutes
(see Figure 137).
                                    317
-------
                              FIGURE  136




        PKIL'JOLICS FORMATION IN THE NITROGEN/FOURFOLD 310 NMO.'-ETER




                       INTENSITY IRRADIATION.
    u.o
CO
o
o
a
PL,


pq
    3.0
                                        800   1000
1200
                                318
-------
                                 rUHB  137
         PEENOLICS jOKiATION III THE NITROGEN /SIMULATED TROPOSPHERIC




                            IRRADIATION.
    lt.0
    3.0
CO
8  2.0
   1.0
   0.0 ,
               O





               A   RUN 2
200
          J	1
                              600      800     1000   1200
                              319
-------
In the air irradiations made with the same lamp balance, aldehydes
averaged 0.37 ppm (as HCHO) at the end of the irradiations.   The phenolics
peaked around 200 minutes at about 1.5 ppb (see Figure 138).

It should also be noted that at the end of all irradiations,  a character-
istic aldehydic odor was evident.  Although this was reminiscent of the
odor of low molecular weight aldehydes, spot checks by gas chromato-
graphy with a flame ionization detector failed to reveal any C2 to €5
aliphatic aldehydes.

The results of the aldehyde production should be viewed in light of the
photochemistry of aldehydes.  The CHO group absorbs and dissociates the
a hydrogen in the 310 nanometer band.

Thus, it is surprising that at the fourfold 310 nanometer intensity,
there is more aldehydes remaining than is present at the same nitrogen
irradiation under the balanced lamp array.  Since the aldehydes would be
expected to be higher with less than 310 nanometer radiation, the
efficiency of the production of aldehydes is more efficient than its
destruction process.

A comparison of the irradiations conducted in air vs nitrogen reveals
lower aldehydes remaining at the end of the air irradiation.   This is
probably a result of further oxidation of aldehydes in the oxygen rich
air.

Figures 136 and 137 demonstrate the phenolics profile observed upon
quadrupling the 310 nanometer band.  As can be seen, the phenolics peak
much earlier at the higher 310 band in nitrogen.  The production of
phenolics is accelerated by the shorter wavelengths and probably its
destruction rate since it disappears shortly after its maximum is
attained.  The presence of oxygen  (Figure 138) also increases the rate
of destruction.

Light Scattering Aerosol -  Light  scattering aerosol measurements on the
air and nitrogen irradiations produced surprising results.  Figures 139
and 140 exhibit the formation of aerosol expressed as the scattering
coefficient due to particles in the range of 0.5 to 5 microns  (molecular
scattering is small).  In terms of scattering coefficient in both irradi-
ations, b scat increased from 0.23 to  100.  Converted empirically to mass
loading, this represents an increase from less than 10 micrograms/M  to
3-5000 micrograms/M^.

An exploratory experiment conducted at low relative humidity  (less than
10%) also showed the same high aerosol formation.  Since hydrogen chloride
has a high vapor pressure at room  temperature it is unlikely that it would
account for the aerosol observed.  Oxygenated aromatics such as 0-hydroxy-
biphenyl, however, have low vapor  pressures at room temperature.  Thus,
it is not likely from vapor pressure considerations that the light scat-
tering aerosol formed is of organic character.
                                    320
-------
                             FIGURE 138

        PKENOLICS  FORMATION  IN THE AIR/SIMULATED TROPOSPHERIC

                           IRRADIATION.
    t.O
    3.0
8   2.0
pq
fc
                   A   RUN 1

                   D   RUN 3
1000
                                                     1200
                               321
-------
                             FIGUES 159



       LIGHT  SCATTERING AEROSOL  FORMATION  IN  THE  NITROGEN/



  SIMULATED TROPCSPHERIC IRRADIATION  (LOG  B    , VS.  TIME).
                                          scat
    100
"O
 H
  •p
  a
  o
  O
     10
200
600    800
1000
                                                      1200
-------
                         FIGURE 140
    LIGHT SCATTtPIZJG AEROSOL FORMATION IN THE  AIR/SIMULATED


      TSOPOSPIIZP.IC IRRADIATION (LOG B    , VS.  TIME).
                                     scat
  100
   10
-p
K
0
B5
   0.1
                      O  RUN 1


                      A  RUN 2
                     _L	L	__.
             200     1(00     600     600    1000    1200
                            323
-------
The results of this investigation indicate that 2-chlorobiphenyl is
degraded in the troposphere through photochemical processes to mainly
aldehydes and hydrogen chloride with minor yields of phenolics and phos-
gene.

The observed results indicate that the absorption of radiation of wave-
lengths between 290 nanometers to 310 nanometers leads to the degradation
of 2-chlorobiphenyl.  The weakest bond, the carbon-chlorine, is probably
cleaved.  This is supported by the appearance of hydrogen chloride and
phosgene.

The bulk of the organic fraction appears to be converted to aldehydic and
phenolic compounds.  The detection of total aldehydes as collected by the
bisulfite addition, along with the characteristic odor of short chain
aliphatic aldehydes prompted efforts to pinpoint specific aldehydes.
However, spot checks for acetaldehyde, proprionaldehyde, and benzaldehyde
produced negative results.  The exact identity of the aldehyde(s) remains
unknown.

Phenolic compounds detected in minor amounts representing less than 1% con-
version appear to be transient.  They build up in the early hours of the
irradiation and die off thereafter.  The decrease in concentration may be
due to mechanical removal by condensation and subsequent settling.  Also,
it may be removed by further reaction i.e. photolysis, oxidation, etc.

From an overall view direct photolysis in the troposphere may be a very
significant sink for the PCBs.  Rates of disappearance for biphenyls of
higher chlorine content will probably be faster than 2-chlorobiphenyl
under similar conditions as evidenced by the liquid phase studies.  The
conversion of these compounds to aldehydes, phenols, hydrogen chloride,
and phosgene makes removal by rainout more important since they are more
soluble in water than the parent compounds.
                                    324
-------
               LIST OF PUBLICATIONS AND THESES
1,   "Absolute Determination of Phosgene:  Pulsed Flow Coulometry" by
     A. Appleby, H.B. Singh, D. Lillian; Anal. Chem., 47_, 860(1974).

2.   "Fates and Levels of Ambient Halocarbons" by D. Lillian, H.B. Singh,
     A. Appleby, L. Lobban, R. Arnts, R. Gumpert, R. Hague, J. Toomey,
     J. Kazazis, M. Antell, D. Hansen, and B. Scott; A.C.S. Symposium
     Series, 17_, 152(1975).

3.   "Gas Chromatographic Methods for Ambient Halocarbon Measurements"
     by H.B. Singh, D. Lillian, A. Appleby, and L. Lobban; Env. Letters,
     (accepted for publication).

4.   "Atmospheric Formation of Carbon Tetrachloride from Tetrachloro-
     ethylene" by H.B. Singh, D.  Lillian, A. Appleby, and L. Lobban;
     Env. Letters, 1.0, 253(1975).

5.   "Atmospheric Fates of Halogenated Compounds" by D. Lillian,
     H.B. Singh, A. Appleby, L. Lobban, R. Arnts, R. Gumpert, R. Hague,
     J. Toomey, J. Kazazis, M. Antell, D. Hansen, and B. Scott; Env. Sci.
     and Techn., 9_, 1042(1975).

6.   Comment on "Atmospheric Halocarbons:  A Discussion with emphasis on
     Chloroform" by Y.L. Yung, M.B. McElroy and S.C. Wofsy; Geophys.
     Res. Letters, 3_, 237(1976).

7.   "Gas Chromatographic Analysis of Ambient Halogenated Compounds," by
     D. Lillian, H.B. Singh, and A. Appleby; J.A.P.C.A., 26^ 141(1976).

8.   "Atmospheric Formation of Chloroform from Trichloroethylene" by
     A. Appleby, J. Kazazis, D. Lillian, and H.B. Singh; Env. Letters,
     (accepted for publication).


Student Research Theses:

1.   J. Kazazis, "Atmospheric Fates of Trichloroethylene and Ethylene
     Dichloride."

2.   R. Gumpert, "An Investigation of the Ambient Behavior and Atmos-
     pheric Chemistry of Carbon Tetrachloride, Methyl Iodide and 1:1:1
     Trichloroethane,"

3,   L. Lobban, "The Atmospheric Fates of C2C14, CF2C12 and CFC13."

4.   J, Toomey, "Atmospheric Fates of Vinyl Chloride and Methylene Chloride,"

5,   R. Arnts, "Photodegradation of Ortho-chlorobiphenyl under Simulated
     Tropospheric Conditions."
                                    325
-------
                                 REFERENCES
1.    Molina, M.J., and F.S. Rowland.  Nature. 24£:810, 1974.

2.    Cicerone, R.J., R.C. Stolarski, and S. Walters.  Science. 185:1165,
      1974.

3.    Chem. and Eng. News. 52^:6, 1974.

4.    Singh, H.B., D. Lillian, A. Appleby, and L. Lobban. Env. Letters,
      in press.

5.    Lillian, D., H.B. Singh, A. Appleby, and L. Lobban. J. Air  Poll.
      Control. 26_:141, 1976.

6.    Chem. and Eng. News. 52_:5, 1974.

7.    Chem. and Eng. News. 52;.44, 1974.

8.    Lovelock, J.E. Nature. 23p_:379, 1971.

9.    Hester, N.E., E.R. Stephens, and O.C. Taylor.  J, Air Poll. Control
      Assoc.  2£:591, 1974.

10.   Lovelock, J.E., R.J. Maggs, and R.J. Wade.  Nature.  241:194,  1973.

11.   Lillian, D., and H.B. Singh.  Anal. Chem.  46_:1060, 1974.

12.   Lovelock, J.E.  Atmos. Environ.  6^:917, 1972.

13.   Wilkness, P.E., R.H. Lamontagne, R.E. Larson, J.W. Swinnerton,
      C.R. Dickson, and T. Thompson.  Nature Phys. Sci.  245:45,  1973.

14.   Murray, A.J., and J. P. Riley.  Nature.  242:37, 1973.

15.   Goldberg, E.D., and Chih-Wu Su.  Nature.   245_:27, 1973.

16.   Simmonds, P.G., S.L. Kerrin, J.E. Lovelock, and  R.H. Shair.
      Atmos. Environ.  8^:209, 1974.

17.   U.S.  Int. Trade Comm, Prelim. Report,  (Feb. 5, 1975).

18.   Weaver, E.R., E.E, Hughes, S,M. Gunther, S. Schuhmann, N,T. Redfearn,
      and  R, Gorden.  J. Res. Nat. Bur. Stand.   59_:383, 1957.

19.   Lovelock, J.E.  Nature.   25_2_:292, 1974,

20,   Saltzman, B.E., A.I. Coleman, and C.A. demons.  Anal. Chem.
      38_;753, 1966,

                                    326
-------
21.   Wilson, K,W.  SRI Project PSC-6687 (Sept. 1969).

22.   Chemical Marketing Report (August 21, 1972).

23.   Hudlicky, M.  Chemistry of Organic Compounds.  New York, MacMillan,
      1962.  p. 840.

24,   Encyclopedia of Marketing Technology,  2nd Edition, Vol. 1. pp. 307-
      325.

25.   Ethylene and its Industrial Development,  S.A. Hiller (ed.). pp. 808,
      812, 859.

26.   Huybrechts, J., T. Olbregts, and K. Thomas.  Trans. Faraday Soc.
   >   63_:1647, 1967.

27.   Horowitz, A., and L.A. Rajbenbach.  J.A.C.S,  9£:4105, 1968.

28.   Goldfinger, P., G. Huybrechts, and G. Martens.  Trans. Faraday Soc.
      57j2210, 1961,

29.   Dusoleil, S., P. Goldfinger, A.M. Malieu-Van der Auwera, G. Martens,
      and D. Van der Auwera.  Trans. Faraday Soc.  57_:2197, 1961.

30.   Kuriyang, T.  Chem. Abs.  67, 1967.

31.   Reid, F.H., and W.R. Halpin.  Amer. Ind. Hygiene Assoc.  29:390,
      1968.

32.   Williams, I.H.  Anal. Chem.  37_:1723, 1965.

33.   Bucknell, M.  Brit. J. Ind. Med.  7;122, 1950.

34.   Charlson, R.J., and S.S. Butcher.  An Introduction to Air Chemistry.
      New York, Acad. Press, 1972.  p. 144.

35.   Junge, C.E,  Air Chemistry and Radioactivity.  New York, Acad.
      Press, 1963.  p. 93.

36.   Garland, A., and F.E. Camps.  Brit.. J. Ind. Med.  2_:209, 1945.

37.   Documentation of the Threshold Limit Values for Substances in
      Workroom Air,  Am, Conf. of Govt, Ind. Hyg.  166, 1971.

38.   Lillian, D., H.B. Singh, A. Appleby, L. Lobban, R. Arnts,
      R, Gumpert, R. Hague, J, Toomey, J. Kazazis, M. Antell, D. Hansen,
      and B. Scott.  Env. Sci. § Techn.  9_:1042,  1975.

39.   Bates, J.R. and R. Spence.  J.A,C.S.  5_3:1689, 1931.

40.   West, W., and L. Schlessinger.  J.A.C.S.  60;961, 1938.
-------
41.   Iredale, T.  Trans. Faraday Soc.  35J458, 1939.

42,   Leighton, P.A,  Photochemistry of Air Pollution.  New York,
      Acad, Press, 1961.

43.   Iredale, T,, and E,R. McCartney,  J.A.C.S.  6^:144, 1946.

44.   Schultz, R.D., and H.A. Taylor.  J. Chem. Phys.  18_:194, 1950.

45.   Willard, J.E,  Annual Review of Phys. Chem, 6^,  Rollefosn, G.K.,
      and R.E. Powell (eds.).  Stanford, California, Annual Reviews,  Inc.,
      1955,

46.   Martin, R.B., and W.A. Noyes, Jr.  J.A.C.S.  75_:4183, 1953.

47.   Hudson, R.P., R.R. Williams, Jr., and W.H. Hamill.  J. Chem.  Phys.
      2^:1894, 1953.

48.   Souffie, R.D., R.R. Williams, Jr. and W.H. Hamill.  J.A.C.S.  78_:
      917, 1956.

49.   Christie, M.I.  Proc. Royal Soc. of London.  244A:411, 1958.

50.   McKellar, J.F., and R.G.W. Norrish.  Proc. Royal Soc, of London.
      263A:51, 1961.

51.   Heicklen, J. and H.S. Johnston.  J.A.C.S.  84_:4030, 1962.

52.   Doepker, R.D., and P. Ausloos.  J. Chem. Phys. 41_:1865, 1964.

53.   Mains, G.J., and D. Lewis.  J. Phys. Chem.  74_:1694,  1970.

54.   Gilbert, J.R., R.M. Lambert, and J.W. Linett.  Trans. Faraday
      Soc.  66_:2837, 1970.

55.   Lewis, C.E.  J. Occupational Med.  3_:82, 1961.

56.   Hazardous  Substances:  Definitions and  Procedural  and Interpretive
      Regulations.  Federal Register.  55, No. 161,  13198(1970).

57.   Hazardous  Substances:  Definitions and  Procedural  and Interpretive
      Regulations.  Federal Register.  33_, No. 102,  7685(1968).

58.   Lyons, E,H., Jr.,  and R.G. Dickinson,   J.A.C.S.   5J7:443,  1935.

59.   Ung, A.Y-M,  and H.I.  Schiff.   Canadian  J. Chem.   40_:486,  1962.

60,   Pfordte, Von K.  Journal  Fur Praktische Chemie,   Series 4,  5j 196,
      1957.                                                       ~
                                    328
-------
61.   Bagdasar'yan? Kh,S., and R.I. Milyutinskaya,  Zhur. Fiz, Khim.  28:
      498, 1954.                                                      ~

62.   Roquitte, B.C., and M.H.J, Wijnen.  J,A.C.S,  85_:2053, 1963.

63.   Solar Radiation.  Robinson, N. (ed,).  London, England, Elsevier
      Publishing Co., 1966.

64.   Tomkinson, D.M., J.P. Galvin and H,0. Pritchard,  J. Phys. Chem,
      68:541, No. 3, 1964.

65.   Clark, D.T., and J.M. Tedder.  Trans. Faraday Soc,  62^:393, 1966.

66.   Lautenberger, W.J., E.N, Jones, and J.G. Miller.  J.A.C.S.  90/.1110,
      1968.

67.   United States Patent No. 3, 034, 903.  Cothran: Brogdex Co.

68.   Federal Register.  35_, No. 161.  13198(1970).

69.   Stewart, R.D., H.H. Gay., D.S. Erley, C.L. Hake, and A.W. Schaffer.
      A.I.H.A.J.  _22_:252, 1961.

70.   Martens, G.J., and G.H. Huybrechts.  J. Chem. Phys.  43^1845, 1965.

71.   Bertrand, L., L. Exsteen-Meyers, J.A. Franklin, G. Huybrechts, and
      Olbregts.  Int. J. Chem. Kinetics.  3^:89, 1971.

72.   Smog Formation - is Trichloroethylene a Contributor.  Env. Sci. §
      Techn.  1966.

73.   Selzer, R.J.  Chem. and Eng. News.  May 19, 1975.

74.   Sax, N.I.  Dangerous Properties and Industrial Materials,  New
      York, Van Nostrand Reinhold Company, 1969.

75.   Huybrechts, G.H. and L. Meyers.  Trans. Faraday Soc.  62_:2191, 1966.

76.   Huybrechts, G., G. Martens, L. Meyers, J. Olbrechts, and K. Thomas.
      Trans. Faraday Soc.  61_:1921, 1965.

77,   Mayo, F., and M. Honda.  The Liquid Phase Antoxidation of Trichloro-
      ethylene.  Presented at:  (A.C.S. meeting. San Francisco, California.
      April 2-6, 1968).

78.   Gay, B.W., P.L. Hanst, J.J. Bufalini, and R. Noonan.  Env. Sci. §
      Techn.  1_0:58, 1976,

79.   Industrial Hygiene and Toxicity.   2nd Revised Edition.  Patty, F.A.
      (ed.).  New York, Interscience, 1963.  II, p. 1303.
-------
80.   Preliminary Assessment of the Environmental Problems Associated
      with Vinyl Chloride and Polyvinyl Chloride.  EPA Report No. 56014-
      74-001.  September 1974.

81.   Chem. and Eng. News.  53;. 11, 1975.

82.   Federal Register.  40_,  40529(1975).

83.   Chem. and Eng. News.  52;27, 1975.

84.   Chem. and Eng. News.  53; 37, 1975.

85.   Chem. and Eng. News.  5_3:34, 1975.

86.   Chem. and Eng. News.  53_:45, 1975,

87.   Koebler, H.  Parfuem u. Kosmetik.  40:625, 1959.

88.   Federal Register,  39.  18116(1974),

89.   Maltoni, C.  Ann. N.Y. Acad. of Sci.  246;195, 1975.

90.   Chem. and Eng. News.  52;14, 1974.

91.   Federal Register.  39_.  30830(1974),

92.   Federal Register.  39_.  14953(1974).

93.   Federal Register.  39_.  30112(1974).

94.   Viola, P.L., A. Bigotti, and A. Caputo.  Concer. Res.  31_:516,  1971

95.   Chem. and Eng. News.  52;4, 1974.

96.   Torkelson, T.R., F. Oyen, and V.K. Rowe.  A.I.H.A.J.   22;354,  1961.

97.   Federal Register.  39_.  12342(1974).

98.   Federal Register.  39_.  35890-35998(1974).

99.   Sanhueza, E., and J. Heicklen.  J.A.C.S.  79_:7678,  1975.

100.  Huie, R.E., J.T, Herron, and D,D. Davis.  Int. J. Chem.  Kinet.
      4_;521, 1972.

101.  Arnold, S.J., G.H, Kimbell, and D.R, Suelling,  Canadian J. Chem.
      52;2608,  1974.

102,  Rennert,  Dissertation  Abstract.
                                    330
-------
103.   Williamson, D.G., and R.J, Cvetanovic.  J.A.C.S.  90^4248, 1968.

104.   Grimsoud, E.P., and R.A. Rasmussen.  Atmos. Environ.  9_:1014, 1975.

105,   Durrans, T.H,, and E,H. Davies.  Solvents,  London, England,
      Chapman and Hall, Ltd,, 1971,  p. 186,

106.   Schnell, H.  Chemistry and Physics of Polycarbonates.  Interscience.
      31, 1974.

107.   Chem. and Eng. News.  5_3:20, 1975.

108.   Milford Citizen.  Milford, Conn.  July 8, 1976,  p.l

109.   Fahrmeir, A.O.  Aerosol Rep.  8^  (2}:62, 1969.

110.   Cannizaro, R.D., and D.A. Lewis.  J. Soc. Cosmet. Chem.  20:355,
      1969.

111.   Bergwein, K.  Kosmet Parfum. Drogen. Rundsch.  15^:105, 1968.

112.   Aerosols - Science and Technology.  Shepherd, H.R.  (ed.).  New York,
      Interscience Publishing Inc., 1961.

113.   Solvents Guide.  Marsden, C. and S. Mann  (eds.).  New York,  Inter-
      science Publishing Inc.

114.   Stewart, R.D., and C.L. Hake.  J. Am. Med. Assoc.   2_35_:398,  1976.

115.   Rinzoma, L.C., and L.G. Silverstein.  J.A.I.H.A.  33_:35, 1972.

116.   Billing, W.L., C.J. Bredeweg, and N.B. Nefertiller.  Env. Sci. §
      Techn.  10^:351, 1976.

117.   Arnold, S.J., G.H. Kimbell, and D.R. Suelling.  Canadian J.  Chem.
      52_:271, 1974.

118.   Lin, M.C.  J. Phys. Chem.  7£:3642, 1971.

119.   Dowty, B.J., D.R. Carlisle, and J.L. Laseter.  Env. Sci. £ Techn.
      9j762, 1975.

120.   Hubbard, H.L.   Kirk-Othmer Encyclopedia of Chemical Technology.
      2nd Edition.  5_:289, 1964.

121,   Polychlorinated Biphenyls - Environmental Impact: A Review.
      Panel on Hazardous Trace Substances.  Env. Research.  5_:249-362,
      1972.

122.   Risebrough, R.W., P. Rieche, D.B, Peakall, S.G. Herman, and
      M,N. Kirven,  Nature.   220:1098-1102, 1968.
                                    531
-------
123.   Anonymous.  Monsanto Will Take Steps to Prevent Environmental
      Buildup of PCBs.   Chem.  and Eng.  News.   51,  1970.

124.   Cook, J.W.  Env.  Health Perspectives.   1_:3,  1972.

125,   Sissons, D., and D.  Welti.  J. of Chromatography.   6£:15-32, 1971,

126.   Anonymous.  Aroclor-plasticizers.   Monsanto  Technical Bulletin,
      0/PL-306A.

127.   Anonymous.  Monsanto Releases PCB Data.  Chem.  and Eng. News. 15,
      1971.

128.   Hustert, K., and F.  Korte.  Chemosphere.  4_:153-156, 1974.

129.   Nisbet, I.C.T., and  A.F. Sarofin.   Env. Health Perspectives.
      l_:21-38, 1972.

130.'   Crosby, D.G.  The Nonmetabolic Decomposition of Pesticides.  Ann.
      N.Y. Acad. of Sci.  160_:82, 1969.

131.   Plimmer, J.R.  The Photochemistry of Halogenated Herbicides.  Residue
      Reviews.  3_3_:47,  1970.

132.   Rosen, J.D.  Photodecomposition of Organic Pesticides.  In Organic
      Compounds in Aquatic Environments.  Faust, S.D,, and J.V. Hunter
      (eds).  New York, Marcel Dekker.

133.   Beruen, G.H., and M. Hall.  The Relation Between Configuration
      and Conjugation in Diphenyl Derivatives, Part. VII.  Halogendi-
      phenyls.  J. Chem. Soc. of London.  4637, 1956.

134.   Friedel, R.A. and M. Orchin.  Ultraviolet Spectra of Aromatic
      Compounds.  New York, John Wiley, 1951.

135.   Pickett, L.W., G.F.  Walter, and H. France.  The Ultraviolet Absorp-
      tion Spectra of Substituted Biphenyls.  J. Amer. Chem. Soc.  58:
      2296-2299, 1936.

136.   Sadtler Standard Spectra.  Sadtler Research Laboratories,
      Philadelphia, Pennsylvania.

137.   Williamson, B., and W.H. Rodebush.  J. Amer. Chem. Soc.  63:3018,
      1941.

138,   Wagner, P,J.  Conformational Changes Involved  in the Singlet-Triplet
      Transitions of Biphenyl.  J, Amer. Chem. Soc.  89_: 2820-2925, 1967.

139.   Baltrop, J,A., N.J.  Bonce, and A. Thomson.  J. Chem. Soc. of London,
      C:1142, 1967.
                                    332
-------
140.  Henderson, W.A,, and A, Zweig.  J. Amer. Chem, Soc.  89/.677S, 1967.

141.  Kharasch, N.,  R,K. Sharma, and H.B. Lewis.  Chemical Communications.
      1.3:418, 1966.

142.  Kharasch, N. ,  and R.K. Sharma.  Chemical Communications.  4_:106,
      1966,

143.  Pinhey, J.T.,  and R.D.G. Rigby.  Tetrahedron Letters.  16:1267,
      1969.                                                         \

144.  Sharma, R.K.,  and N. Kharasch.  Angew. Chem.  7^:36, 1968.

145.  Wolf, W., and  N. Kharasch.  J. Org. Chem.  3£:2493, 1965.

146.  Calvert, J.G., and J.N. Pitts.  Photochemistry.  New York, John
      Wiley, 1966.

147.  Herring, J.L., E.J. Hannan, and D.D. Bills.  Bulletin of Environ-
      mental Contamination and Toxicology.  8_:153, 1972.

148.  Hutzinger, 0., S, Safe, and V. Zitko.  Environmental Health
      Perspectives.   1_:15, 1972.

149.  Andersson, K., A. Nordstrom, C. Rappe, B. Rasmuson, and H. Swahlin.
      Abstracts. (166th National Meeting of the American Chemical Society.
      Chicago, Illinois. August 1973).

150.  Nordblum, D.,  and L.L. Miller.  J. Agric. and Food Chem.  22:57,
      1974.

151.  Ruzo, L.O., M.J. Zabik, and R.D. Schuetz.  Bulletin of Environmental
      Contamination  and Toxicology.  8_:217, 1972.

152.  Ruzo, L.O., M.J. Zabik, and R.D. Schuetz.  J. Amer. Chem. Soc.  96:
      3809, 1974.

153.  Veith, G.D., and G.F. Lee.  Water Research.  5_:1107, 1971.

154.  Harvey, G.R.,  and W.G. Steinhauer.  Atmos. Environ.  8_:777, 1974.

155.  Tarrant, K.R., and J. Tatton.  Nature.  n9_:725, 1968.

156.  Sodergren, A.   Nature.  2^6_:395, 1972.

157.  Birox, F.J., A.C, Walker, and A. Medbary.  Bulletin of Environmental
      Contamination and Toxicology.  5_;317, 1970,

158.  Anonymous,  EPA, FDA Crackdown on Toxic Pollutants in Chem, and Eng.
      News.  July 16, 1973.  p. 10.
                                   333
-------
159.   Anonymous.  International Notes in Chem,  and Eng.  News.
      December 18, 1972.  p. 7.

160.   Council on Environmental Quality.  Environmental Quality - the
      Fourth Annual Report.   1973.   p. 188.

161.   Reed, R.M,  Anal. Chem.  30;221, 1958.

162.   Dresdner, R.D., T.M. Reed, R.E. Taylor, and J.A, Young.  J. Org.
      Chem.  25;1464, 1960.

163.   Ellis, J.F., C.W. Forrest, and P.L. Allen.  Anal.  Chem. Acta.
      22;27, 1960.

164.   Nachbaur, E., and A. Engelbrecht.  J.  Chromatog.  2_:562, 1959.

165.   Campbell, R.H., and B.J. Gudzinowicz.   Anal. Chem.  33_:842, 1961.

166.   demons, C.A., and A.P. Altshuller.  Anal, Chem.  38/.135, 1966.

167.   Greene, S.A., and P.M. Wachi.  Anal. Chem.  3_5_:928, 1963.

168.   Lysyj, I., and P.R. Newton.  Anal. Chem.   35_:91, 1963.

169.   Williams, F.W., and M.E. Umstead.  Anal.  Chem.  40;2232, 1968.

170.   Priestley, L.J., F.E.  Critchfield, N.H. Ketcham, and J.D.
      Cavender.  Anal. Chem.  37;70, 1965.

171.   Jeltes, R., E. Burghardt, and J. Breman.   Brit. J. Industr. Med.
      28;96, 1971.

172.   Turk, A., S.M. Edmonds, H.L.  Mark, and G.F. Collins.  Env. Sci.
      and Techn.  2;44, 1968.

173.   demons, C.A., A.I. Coleman,  and B.E. Saltzman.  Env. Sci. and
      Techn.  2;551, 1968.

174.   Dietz, R.N. and E.A. Cote.  Env. Sci. and Techn.  7;341, 1973.

175.   Lovelock, J.E., R.J. Maggs, and R,J. Wade.  Personal communications.

176.   Hester, N.E., R.S.  Edgar, and O.C. Taylor.  J. Air Poll, Control
      Assoc.  Presented June  1973.

177.   Standard Methods.   13th Edition,  A.P.H.S.A.  240, 1971.

178.   Braverman, M.M.,  S. Hochheiser, and M.B, Jacobs.  Colorimetric
      Ultramicro Determination  of Phenol  in Air from  Industrial  Hygiene
      Quarterly.   18:132, 1957,
                                   334
-------
179.   Jacobs,  M.B,  The Chemical Analysis of Air Pollutants.  New York,
      John Wiley, 1960.

180.   Hoffman, C.  Personal communications,

181.   Lovelock, J.E,  In:  Gas Chromatography 1968.  Harbourn, C.L.A. (ed),
      Amsterdam, Elsevier, 1969.

182.   Lovelock, J.E,, R.J. Maggs, and E.R. Adlard.  Anal. Chem.  45:1962,
      1971.

183.   Wentworth, W.E., and J.C. Steelhammer.  Adv. Chem. Series.  82:75,
      1968.

184,   Dahlberg, J.A., and I.B. Kihlman.  Acta Chem. Scand.  24:644, 1970.

185.   Kolthoff, I.M., J.E. Phillip, and F.H. Strauss.  Treatise on
      Analytical Chemistry, Part III.  In:  Analytical Chemistry in
      Industry. 2_:75, 1971.  New York, Wiley Interscience.

186.   Noweir,  M.H., E.A. Pfitzer, and T.F. Hatch.  Amer. Ind. Hyg. Assoc.
      J.  34jllO, 1973.

187.   Singh, H.B., D. Lillian, and A. Appleby.  Anal. Chem.  £7:860, 1975.

188.   U.S. Tariff Commision Reports, 1974.

189.   Anonymous.  More Ozone Bombshells.  In:  Ind. Res.  16, 1974.

190.   Anonymous.  Chem. and Eng. News. September 23, 1974.  p. 27.

191.   Spinks,  J.W.T.  Chem. and Eng. News.  June 23, 1975.  p. 3.

192.   Compilation of Air Pollution Emission Factors, 2nd Edition.
      U.S.-E.P.A., Ap-42.  April 1973.

193.   Heicklen, J.  Advances in Photochemistry.  7j57, 1969.

194.   Blaedel, W.J., R.A. Ogg, Jr., and P.A. Leighton.  J.A.C.S.  64_:2500,
      1942.

195.   Pitts, J.N., Jr., and F.E. Blacet.  J.A.C.S.  74_;455, 1952.

196.   McConnell, G., D.M. Ferguson, and C.R. Pearson.  Enderour.  34_:13,
      1975,

197,   Wilson,  K.W., and O.J. Doyle.  SRI Project PSO 8029.  Invine, Cali-
      fornia.   September 1970.

198.   Wofsy, S.C., and M.B. McElroy.  Canad. J. Chem,  52:1582, 1974.
                                      335
-------
199.   Noyes, W.A., and P.A,  Leighton.   Photochemistry of Gases,   New York,
      Dover Publications,  1941.
-------
                                   TECHNICAL REPORT DATA
                            (Please read Instructions on the reverse before completing)
1  REPORT NO.
   EPA-600/3-76-1U8	
4 TITLE AND SUBTITLE
   ATMOSPHERIC FREONS AND HALOGENATED COMPOUNDS
                                                           3. RECIPIENT'S ACCESSION NO.
             5. REPORT DATE
               November 1976
                                                           6. PERFORMING ORGANIZATION CODE
1 AUTHOR(S)
    Alan Appleby
                                                           8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
    Rutgers University
    Department of Environmental  Science
    New Brunswick, New Jersey    08903
             10. PROGRAM ELEMENT NO.
                1AA603 (1AA008)
             11 CONTRACT/GRANT NO.
                R-800833
12. SPONSORING AGENCY NAME AND ADDRESS
    Environmental Sciences Research Laboratory
    Office of Research and Development
    U.S.  Environmental Protection  Agency
    Research Triangle Park, North  Carolina  27711
             13. TYPE OF REPORT AND PERIOD COVERED
                Final Report	
             14. SPONSORING AGENCY CODE
                EPA-ORD
15. SUPPLEMENTARY NOTES
16. ABSTRACT
         Ambient levels of atmospheric Freons, halogenated hydrocarbons, and SF, were
    measured at various locations  in the U.S.A.  Compounds such as CC1.F, CC12F2,
    CH -CC1_,  and CC1. were ubiquitious and generally measured  at sub ppb levels.
    Tropospherically reactive  compounds such as C Cl  and CHCICCI- were frequently
    measured;  other compounds  were measured where a reasonable  source was known.  A
    novel pulsed flow coulometry gas chromatographic analysis along with other requisite
    analytical and calibration procedures were developed and used.  Laboratory
    irradiation simulations established the tropospheric stability of CC1-F, CC1-F  ,
    CH CC1_, CC1., CC1 FCC1F  , the reactivity of the chlorinated ethylenes, and the
      J   J     *T     L.     £.
    stratospheric reactivity  of CC1 F, CC1., and CC1 F  .  Adventitious labelling of
    air masses with halogenated compounds was used to demonstrate urban ozone transport
    to rural areas.
17.
                               KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
       Air pollution
       Halohydrocarbons
       Atmospheric composition
       Chemical analysis
                                              b.IDENTIFIERS/OPEN ENDED TERMS
                             COSATI Field/Group
                              13B
                              07C
                              04A
                              07D
18 DISTRIBUTION STATEMENT
    RELEASE TO PUBLIC
19 SECURITY CLASS (This ReportJ
    UNCLASSIFIED
21 NO. OF PAGES
    357
                                              20 SECURITY CLASS (This page]
                                                                         22. PRICE
EPA Form 2220-1 (9-73)
                                            337
-------