chemicals in the enivironment

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					Envr 210
   Tues. and Thurs- 3 credit hours: Room 1001 Hooker-
    SPH
   11am to 12:15 pm
    snow days call me at 942 4880 or
    cell 919 614 4730
   room 2304
   http://www.unc.edu/courses/2006spring/envr/210/001/Env
    r210.html
   Rich Kamens; 966 5452
   kamens@unc.edu
   http://airsite.unc.edu/~kamens/

                                                         1
    Introduction to Environmental
    Physical Organic Chemistry

   Environmental chemistry may be defined
    as "the study of sources, reactions,
    transport, effects, and fates of chemical
    species in water, soil, and air
    environments, and the effects of
    technology thereon.” Manahan, 1994



                                           2
    Class objectives:

   Highlight some important areas in
    environmental chemistry

   present some of the common techniques that
    environmental chemists use to quantify
    process that occur in the environment

 It  is assumed that everyone has courses in
    organic and physical chemistry.
                                                3
Class objectives:

             is a thread that runs
 Partitioning
 through the course

 Linear free energy relationships
 will be used to help quantify
 equilibrium and kinetic processes



                                     4
Thermodynamics

 ui  = uo1 +RT ln pi/p*iL
 fi = i Xipi*pure liquid


 RT   ln fi hx /fiopure liq = RT lnfi H2O /fiopure liq

  fi hx = fi H2O

 ln   Kp = a 1/T+b
                                                          5
Vapor pressure
                      Tb        Tb
      ln p *iL 19(1  ) 8.5(ln )]
                      T         T


    How to calculate boiling points




                                ( S fus ) (Tm  Tamb )
       ln    *
            piL    ln p is 
                        *
                                   R         Tamb
                                                          6
Vapor pressure and Henry’s law


                P isat
    K   sat                 sat      *
                                     P iL V iw
        iaw
                C sat
                    iw
                               iw



    Solubility and activity
    coefficients


    Octanol-water partitioning
    coefficients

                                                 7
Additional Principles
   Organic    Acid-bases and LFERs
   diffusion

   chemical    spills and mass transfer
   Organic    reactions in the environment
   Solid-   liquid interactions
     photochemistry

                                              8
Homework, quizzes, exams
  To  insure that most of us stay reasonably
   current with the lectures and readings, an
   option is to have 6-8 unannounced
   quizzes throughout the semester.
  They will take ~10 minutes. The first quiz
   will be on Chapter 2 since we will not cover
   Chapter 2. Quizzes will count 10% of your
   grade.


                                             9
 Another option is a set of short
 questions to be answered and handed
 in before most lectures (5% of
 grade)—your choice!




                                  10
 There   will be a homework problem set
    associated with each assigned chapter of
    the book. It is due a week after the
    completion of the book chapter.


   These problem sets should take between 3
    and 10 hrs.     Answers will graded and
    returned to you as soon as possible. These
    will count for 25% of your grade.



                                               11
 In addition, you are expected to work
  through the illustrative examples and
  problems
  which have answers in the test on your
  own.

 Some    of these could appear on exams

 There will be three exams (70% of your
  grade ), 25% homeworks, 5%???




                                           12
    Important Environmental Issues
   Global warming and stratospheric ozone
    depletion

   Concentration of environmental pollutants at
    the poles; pesticides in foods, etc.

   Buildup of environmental chemicals in the
    oceans; contamination of soil and ground water

   Particle exposure, photochemical oxidant
    exposure, acid deposition

   Energy shortages
                                                     13
 Why the interest?
      are more than 70,000 synthetic
 There
 chemicals that are in daily use:
  – solvents
  – components of detergents
  – dyes and varnishes
  – additives in plastics and textiles
  – chemicals used for construction
  – antifouling agents
  – herbicides, insecticides,fungicides
Some examples of
environmental chemicals
 Polynuclear Aromatic HC (PAHs)
 Dioxins
 Ketones
 PCBs
 CFCs
 DDT
 O3, NO2, aerosols, SO2
  PAHs
 Formed  from small ethylene radicals “building
  blocks” produced when carbon based fuels
  are burned

 Sources    are all types of burning

 in   ChiangMai, Thailand:
                   a) 2-stroke motorcycle engines
                   b) cars- light diesels
                   c) open burning
                   d) barbecued meat??
Combustion Formation of PAH
                            Badger and Spotswood 1960



                        C
                                                   C                    C
  C                 C                                  C                    C
  C                 C
                       C                                                    C
  (I)               (II)                   (III)                 (IV)   C


   Benzo a Pyrene




          (VII)                         (VI)               (V)

                                                                                17
 Some PAH structures
                    fluoranthene
naphthalene


anthracene      benz(a)anthracene




 phenanthrene
                benzo(a)pyrene [BaP]   18
    PAHs
Naphthalene,    phenanthrene and
    anthracene are found in the gas
    phase
    pyrene and fluoranthene are in both
    the gas and particle phase
BaA     and BaP are mostly on the
    particles, Why???
    PAHs
Metabolized    to epoxides which are
    carcinogenic; O PAH

are indirect acting mutagens in
 bacterial mutagenicity tests (Ames-
 TA98+s9)
methyl PAHs are often more
 biologically active than PAHs
 Carcinogenic tests with PAHs
Professor   Gernot Grimmer extracted
 different types of smoke particles
 He then took the extract and applied it to
  mouse skin
 and implanted it into rat lungs


 How did he obtain extracts?
 How did he fractionate his extracts??
 Extractionby soxhlet extraction starts
 with solvent (MeCl2) in a flask




                                           22
 Hotsolvent fills this chamber and
 bathes the filter




                      Heat
                                      23
 The  solvent in the filter chamber then
 drains back into the heated flask with
 chemicals
 from the
 particles
 on the
 filter



                           Heat
                                            24
 The organic liquid in the soxhlet
 flask can be concentrated by
 evaporation by a dry nitrogen
 stream or rotary evaporation
 theextract can then be
 fractionated into different polarity
 compound groups


                                        25
 Professor Grimmer fractionated
 the exhaust extracts

Total
        HPLC                uv or
                            fluorescence
                            detector




               Total

                       PAH 2    PAHs> Total
                       &3 rings 3 rings -PAHs
                                           26
What did Grimmer see when
exposed rats and mice to the
different fractions?

   skinpainted mice
   implanted rat lungs




                               27
            40


            30
% cancers




            20


            10


             0
                 Total               PAHs 2&3 rings
                            Total-PAHs          PAHs > 3 rings


                         rat lungs       Mouse-skin
Analysis of reaction products

 soxhlet  extraction for 3 hours
   – blow up with dry gentle flow of nitrogen to
     about 0.5 to 1 ml
 evaporation to about 0.5 to 1 ml
 1 to 2 ul injected directly to GC-MS (EI and CI)
 The remainder solution: derivatization




                                                29
In environmental samples why
don’t we see some large highly
oxygenated compounds that form
in the atmophere??

Reverse reactions to the original
aldehyde parent structures can occur
during sample work up/solvent
extraction procedures;

                                       30
PFBHA O-(2,3,4,5,6-pentafluorobenzyl)
-hydroxylamine for carbonyl groups

     acetone or ketone               PFBHA
                                 F       F
              O

              C              F                CH2 O   NH2
         R1       R2
                                 F       F

                         F   F

R1
     C    N   O   CH2            F           H2O
R2
                                                       31
                         F   F
Pentafluorobenzyl bromide (PFBBr)
derivatization for carboxylic and hydroxyl groups
                                                                         PFBB r
                                                                    F           F
                    H3C         CH3         O
               O

          HO   C                      CH2   C   OH             F                     CH2 Br



                                                                     F          F

                                                       F        F
                   H3 C     CH3         O
               O

          HO   C                  CH2 C     O   CH2                  F              HB r


                                                       F        F




                                                                            F          F
          F         F
                                       O CH3     CH3       O

      F                   CH2     O    C             CH 2 C O       CH2                    F   2 HB r


                                                                            F          F
                                                                                                        32
          F        F
BSTFA for carbonyl, hydroxyl, and/or carboxylic
                                              BSTFA
   carboxylic acid
    or alcohol                      CF3

                                              C     N
      R     OH
                          (CH3)3Si                      Si(CH3)3
                                          O



                         H2N

                                C       O
 (CH3)3Si   O
                          F3C
                 R
                     +    CF3

                                    C     NH

                                                  Si(CH3)3         33
                                O
GC-EIMS for Oxygenated Terpenoids
Compound           Structure           m /z (EI) Compound                Structure            m /z (EI)
Mw, g mol-1                                      Mw, g mol-1
a-Pinene oxide                 O       67 (100) Nopinone                                      83 (100)
Mw=152                                 109       Mw=138                                       55
                                       83                                  O
                                                                                              95
                                       152                                                    109
b-Pinene oxide                         79 (100) Menthone                                      83 (100)
                               O
Mw=152                                 71        Mw=154                                       56
                                       41                                                     112
                                                                                     O
                                       152                                                    140
                                                                               C

Limonene-2-oxide          O            67 (100)   Camphore                                    95(100)
Mw=152                                 94         Mw=152                                      81
                                       108                                                O   109
                          H
                                       79                                                     55
                                       137
                                       68 (100)                                               152
d-Limonene                             93         Myrtenol                         CO H       79 (100)
Mw=136                                 79         Mw=152                                      91
                                       136                                                    108
                                                                                              152
2-Hydroxy-3-               OH          71 (100)
                                   O
pinanone                               99       cis -Verbenol                               94 (100)
Mw=168                                 168      Mw=152                                      109
                                                                                        OH  81
                                                                                            137
Cineole                                84 (100)   trans -Pinane-1,10-                    OH 82 (100)
Mw=154                         O       71         diol                   HO                 67
                                       108        Mw=170                                    55
                                       154                                                  70
                                       139                                                  152
Myrtenal                 CHO           79 (100)   trans -p-Menth-6-en-               OH     109
Mw=150                                 107        2,8-diol                                  (100)
                                       135
                                       150
                                                  Mw=170                       C   OH
                                                                                            59
                                                                                            79
                                                                                                          34
Thermal desorption particle beam
mass spectrometry (Paul Ziemann)

                   Particle generator or
                   smog chamber




                                           35
    Chlorinated dibenzo dioxins and
    Furans
 These   are some of the most toxic
    organics in the environment - LD50

 Created    by burning organics which have
    chlorine; incineration is a big source of
    atmospheric dioxins and furans

   bleaching in making paper is another
    source
Combustion Formation of Dioxins from
Polychlorinated phenol
       OH
                                                     Clx
                     OH .


                     Flame
 Clx
                                                .O
                                       OH   +
 Polychlorinated
 Phenol
                             C ly




                                                                 O
                                    + OH
            O

                       Cly
 Clx            OH                                               O
                                                                                  Cly
                                                Clx
                                       Chlorinated dibenzo dioxin
                                                                                        37
                                                      Shaub & Tsang, ES&T 1983.
They have the following general
structures
            O             Clx

   Cly      O   chlorinated dioxin
They have the following general
structures
            O             Clx

   Cly      O   chlorinated dioxin

            O            Clx

  Cly             chlorinated furan
More than 200 different
structures are possible

          Cl     O      Cl
          Cl     O      Cl



 The most toxic is either the 2,3,7,8
 tetrachlorodibeno dioxin or furan
 These types of compounds produce
 toxic enzymes: arylhydrocarbon
 hydroxylase and 7-ethoxyresorufin
 deethylase

Atlow concentrations they may
 behave as environmental estrogens
 Environmentally,they are unreactive
 and can be transported long distances

 They did not start to show up in the
 environment until the 1920s when
 there was a big increase in the
 production of chloro-organics
 (Professor Ron Hites, and students)
Environmental Fate of Chlorinated
       Dioxins and Furans
             (Czuczwa and Hites, 1984)



 Collected  core sediment samples from
    southern Lake Huron in the USA

   Based on sedimentation rates they
    established age vs. concentration
    profiles for chlorinated dioxins and
    furans

                                           43
US coal consumption vs chlorinated
       aromatic production

      US coal in 10^6 short-tons   700                                             800

                                   600




                                                                                         10^6 lbs Cl-aromatics
                                                                                   600
                                   500
                                            Coal
                                   400
                                                                                   400
                                   300
                                                          chloro-
                                   200
                                                          aromatics                200
                                   100

                                     0                                             0
                                     1860   1880   1900    1920   1940   1960   1980
                                                           Year

                                                                                                                 44
Chlorinated aromatic production vs dioxin
and furan conc. in lake core samples

         Total dioxins and furans in ppt   1200                                      800


                                           1000




                                                                                           10^6 lbs Cl-aromatics
                                                                                     600
                                            800


                                            600     chloro-                          400
                                                    aromatics          chlorinated
                                            400                        dioxins and
                                                                       furans        200
                                            200


                                             0                                      0
                                             1900    1920       1940   1960      1980
                                                                Year


                                                                                                                   45
PCBs in the U.S. Great Lakes

   PCBs were banned in the early 1970s

   In 1980 Eisenreich and co-workers
    estimated that still 85% of the PCBs in
    the US great lakes came from
    atmospheric sources.




                                              46
Polychlorinated biphenyls (PCBs)
   Total    Flux = Jair + Jrain + Jparticles

   Jair   = vw ( Cw-P/KH)

    if resistance to mass transfer is in
    the water phase

   Jair   = va (Cw KH - P)/RT
           if resistance is in the gas phase
In the late 1980s a fugacity model
was used to represent the
distribution of PCBs in different
environmental compartments


  RT       ln fair /fiopure liquid = RT lnf H2O /fiopure
   liquid


  fair = f H2O
   In 1990 Eisenreich and co-workers reported
    that ambient measurements over the great
    lakes were generally constant for the past 10
    years.

   For the past 15 years sources to the lakes had
    declined because of the PCB ban.

   Based on mass transfer calculations it was
    proposed that during the summer months the
    lakes were actually a source of atmospheric
    PCBs.

                                                     49
Polychlorinated biphenyls (PCBs)

 used  as coolants - insulation fluids in
  transformers, capacitors , plastercisers,
  additives to epoxy paints
 are thermally stable and biologically
  stable
 can exist in the gas and particle phases
PCB structures

                    Cl x

    Cl y


Environmentally, they used to be
considered unreactive, but there is
evidence for some bio-degradation;
they can be transported long
distances                           51
 Up until the 1970s there was a lot
 of dumping of industrial wastes in
 the USA

   one example, from 1950 to 1975
 In
 there were two capacitor
 manufacturing plants on the
 Hudson river in New York State,
 which discharged into the river.
 Levels  in the river sediments
  downstream from the plants exhibited
  concentrations of 10 ppm which was a
  factor of two higher than commonly
  found.
 Dredging was considered financially
  impossible
 it was also believed that is very
  difficult to bio-degrade PCBs with
  multiple chlorine atoms
 Investigationsin the 1980s
 revealed that PCBs in sediments
 were being slowly converted to the
 mono and dichloro forms via very
 slow anaerobic processes.

 {CH2O}+ H2O + 2Cl-PCB---> CO2
 +2H++ 2Cl-- +2H-PCB
What do we do now, when new compounds
are introduced into the environment...??

   toxicity??
   low concentration health effects?
   damage to the ecosystem ?
   where will it show up in the
    environment?
   how is it transported in the
    environment and what is its life-
    time?

                                        55
An example is a new compound called D5. It
is a silicon-oxygen compound
    Itis used to make silicone
     plastics.

    Itis possible that it could be used
     to replace toxic solvents like
     toluene and dichloro-methane.

    Before   it can be put into use in the
     US, we need to know its toxicity,
     chemical reactivity , environmental
     half-life, etc.                          56
 New compounds are introduced into the
 environment ... Toxicity? Where will it go?


      H3C         CH 3 H3C                                      H3C         CH 3 H3C
                                    CH 3                                                      OH

             Si                Si                                      Si                Si
      O             O                O              OH.         O             O                O

                                             CH 3                                                     CH 3
      Si               Si            Si                         Si            Si               Si
H3C          O                 O                          H3C          O                 O
             H3C        CH 3               CH 3                 CH 3   H3C        CH 3              CH 3
      CH 3



                  D5                                                        D4TOH
                                                                             D4D'OH


                                                                                                             57
    Some examples of
    environmental exposures
 In  1976 there was a significant industrial
    explosion in the town of Seveso, Italy that
    spewed out chlorinated dioxins.

 735  people were evacuated from the
    immediate vicinity.

   Now excess cancers are showing up.
Seveso, Italy Dioxin release

 Overthe past eight years the birth ratio
 has changed from 106 males: 100
 females to 26:48

 observed   increases in cancers

 decline   in number of males born

                                         59
A similar observation has been
made in the bird population
 In  the Great Lake region of the USA
    during the 1980’s, hatchlings of
    crested cormorants with a crossed bill
    deformity were almost always female

 Male   birds did not show the deformity

    Scientist speculate that the chemicals
    causing the deformity were also killing
    the males before they hatched.        60
1. There is a general concern
that if we observe
abnormalities in wildlife,
similar kinds of mechanisms
may exist in humans.

                                61
Mercury poisoning off the coast of
Minamata, Japan is an example
 Fishermen  in the 1950s noticed sea
 birds were dying and feral cats that
 scavenged fish from the docks were
 “stiff legged”

 Cerebralpalsy and mental retardation
 started showing up in children.


                                         62
2. Toxic loads


 Scientistshave hypothesized that the
 fetus is sharing the mother’s toxic
 load, and may actually provide some
 protection to the mother by reducing
 her internal exposure.



                                         63
2. Toxic loads
 Children  get 12% of their lifetime
  exposure to dioxins during the
  1st year.

 Their exposure is 50 times
  greater than an adult during a
  very critical developmental
  period.

                                        64
2. Toxic loads


Firstborns from dolphins off the
 coast of Florida usually die before
 they separate from their mothers




                                       65
2. Toxic loads
 It is speculated that mother dolphins
    unload 80% of their accumulated
    pollutants into their calves, probably
    during nursing.

    The greatest exposures occurs with
    the 1st born

 Does  this have any implications for
    humans?
                                             66
3. Pesticide exposures
 Children   of farm families in the western
    Minnesota area of the US have
    significantly higher rates of birth defects
    than the general population.
   The highest rates are among children
    conceived in the spring when spraying of
    pesticides is most intense; male babies
    had far more birth defects than females

                                             67
4. The end points may not only be
cancer, but compromised
immune systems and generally
poorer health.


                                    68
4. Immune systems & Mother’s milk

   the Netherlands researchers have
 In
 found that children with higher levels of
 dioxins and PCBs in their bodies have
 more health problems (immune system
 and hormonal changes) than children
 with lower levels.
     was linked to levels of PCBs in
 This
 Mother’s milk.
                                        69
4. Mother’s milk


    Overall, however, it was concluded
    that nursing was still of greater
    benefit than bottle feeding babies,
    but that even mild exposures may
    weaken immunity


                                          70
4. Mother’s milk


 Mother’s milk from Inuit Indians in
 the Canadian Arctic has 7 times the
 PCBs as mother’s milk from women
 in the urban industrialized areas of
 southern Quebec.



                                        71
4. Mother’s milk


    During the first year, Inuit babies
    suffer through 20 times more colds
    than babies in southern Quebec.

    Acute ear infections are rampant.



                                           72
4. Mother’s milk

 Babies    nursed by mothers with the
    highest contamination levels in
    their milk are afflicted with more
    acute ear infections than bottle fed
    Inuit babies.
    Many of these children don’t seem
    to produce enough antibodies for
    childhood vaccinations to take.
                                           73
5. PCBs and lower intelligence

    There is evidence of lower intelligence
    in babies exposed to PCBs.

 In  adults, a blood-brain barrier insulates
    the brain from many potentially harmful
    chemicals circulating through the body

   In a human child this barrier is not fully
    developed until 6 months after birth.
                                            74
5. PCBs and lower intelligence

   In 1979 in Taiwan, more than 2000
    people were exposed to PCB-
    contaminated cooking oil.
   In the 1st 3 months many babies died
    outright. As the surviving children grew
    up, many were slower intellectually than
    other kids their age, were hyperactive
    and had behavioral problems.

                                          75
5. PCBs and lower intelligence

    Similar observations were made in
    "high-PCB kids" in the Lake Michigan
    area.

   This was associated with mothers
    eating salmon and trout from the Lake
    during the years before their children
    were born.
                                             76
5. PCBs and lower intelligence

 Atage 4 the high exposure group had
 poor short term memories. At age 11
 the 30 most highly exposed kids had
 average IQ scores that were 6 points
 lower than the lowest-exposed group.

 biomarker-metabolites???


                                        77
6. DDT and immune system damage


 Ina recent study (1998), residents
 whose homes are within a mile of
 Aberdeen, Texas pesticide sites show
 elevated DDE levels in their blood.




                                        78
6. DDT and immune system damage

 DDEis a byproduct of the body’s attempt to
 break down the pesticide DDT, which has
 been banned in the USA since 1972.

 “Levels of plasma DDE in the study
 population overall were low (6ppb) compared
 to nationwide levels between 1976 and 1980,
 just after the DDT ban,” (UNC, Prof. Vine)



                                           79
6. DDT and immune system damage

 Younger  Aberdeen residents – those
 between ages 18 and 40 – and people
 who lived there before 1985 when the
 plants were operating did show a two-
 to three-fold increased risk of herpes
 zoster,

   shingles, which indicates modest
 or
 suppression of the body’s immune
 system                                   80
7. Sexual impairment

 Thereis evidence for sexual impairment
 in both animals and humans from high
 PCB exposures and other
 environmental chemicals.

 Male beluga whales in the very polluted
 St. Lawrence River have exhibited
 female organs.
                                       81
    7. Sexual impairment

 Highly  exposed humans, alligators and
    panthers exhibit smaller male sex organs
    and low sperm counts.
   Testicular cancers have nearly doubled
    among older teenagers in the US between
    1973 and 1992.
 In   previous lectures I have said these have
    been linked to toxic exposures....long way
                                             82
    from finding proof.
  7a. Sexual impairment
 In a new study (Hardwell et al, Environ Presp,
  2003) woman who’ve had substantial exposure
  to certain environmental pollutants are more
  likely to bear sons who develop testicular
  cancers (men ~ 30 years of age)
 From   1973-1999 testicular cancers up 67%
 Men  with test-cancers had high cis nona
  chloridane, not PCBs, etc
 Mothers,however, had high PCBs, HCB (hexa-
  chlorobenzenes) and cis nona chloridane    83
  7b. Sexual impairment
 Thesesame mothers probably had high
 exposures when environmental contaminets
 peaked in Scandinavia in the 1970s
 Richard Sharpe of Edinburogh and Niels
 Skakkebek (Denmark) propose that exposure to
 endocrine disruptors before birth can alter
 testicular-cell development and some of these
 cells may be cancerous after puberty.
 Thismay also may explain rising rates of male
 infertility, and other sexual deformities
                                                  84
8. Endocrine disrupters

 Thesestudies have led to the
 notion of environmental "endocrine
 disrupters".

   the lock and key relationship
 In
 between hormone and receptor
 molecules, these "hormone
 impostors" can:
                                      85
8. Endocrine disrupters


 bindwith receptors and trigger
 biological processes

   bind with receptors and tie up
 or
 an active hormone site

 Some of these have been called
 environmental estrogens
                                    86
9. Other chemicals
 From a historical perspective, everyone is
 now carrying at last 250 measurable
 chemicals that were not part of human
 chemistry before the 1920s (Peter Myers,
 1996)
 The most basic toxicity testing results cannot
 be found in the public record for nearly 75%
 of the top volume chemicals in commercial
 use in the USA

                                               87
9. Other chemicals
 In other words, the public cannot tell whether a
  large majority of the highest-use chemicals in
  the United States pose health hazards or not
  (Amicus Journal, p23, Spring 1998).



 An example are phthalates that go into many
  types of plastics which have been shown to
  reduce the sperm counts in mice.

                                                88
9. Other chemicals

 Bisphenol-A     (BPA) is an additive in
    polycarbonate plastics used in food
    liners, dental sealants, and dental
    fillings.

   BPA causes increased prostate size in
    mice exposed to tiny doses while in the
    womb. These doses were 25,000 times
    smaller than the EPA threshold.
                                            89
9. Phthalates
 Exposure  of female rates to 200 to 1000
 mg/kg body weight results in much
 lower testosterone in male offspring
 ( L. Earl Gray. Jr. EPA, RTP, J. Tox and
 Ind. Health, Mar, 1999).
 Exposures  to the herbicide linuron
 made the epididymis (sperm-storing
 organ in rats) much smaller in male
 rats.
                                         90
epididymus




             91
 Recommendations
 During the insecticide spraying season,
  farmers should not try to have children.
      exposures to pesticides around the
 Limit
  home.
 When  possible, buy foods that were grown
  without pesticides.
 Governments    must try to limit PCB
  introduction into the environment.
 Ifincineration is used, chlorinated plastics
  should be removed, along with modern
  technology.
                                                 92

				
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