United States
             Environmental Protect/on
              September 1 997
Office of Pollution Prevention and Toxics (7406)	
Presidential Green
Award  Recipients


 Introduction	1

                     1997 Winners

 Academic Award
 Professor Joseph M. DeSimone, University of North Carolina at
 Chapel Hill (UNC) and North Carolina State University (NCSU)
 Design and Application of Surfactants for Carbon Dioxide  	2-3

 Small Business Award
 Legacy Systems, Inc.
 Coldstrip™, A Revolutionary Organic Removal and   •
 Wet Cleaning Technology .  . .	,	4.5

 Alternative Synthetic Pathways Award
 BHC Company
 BHC Company Ibuprofen Process  ..-...-	6-7

Alternative Solvents/Reaction Conditions Award
 DryView™ Imaging Systems  . .	,.	     8-9

Designing Safer Chemicals Award
Albright & Wilson Americas
THPS Biocides: A New Class of Antimicrobial Chemistry 	10-11

                      1996 Winners

Academic Award
Professor Mark Holtzapple, Texas A&M University
Conversion of Waste Bio mass to Animal Feed,
Chemicals, and Fuels  	.12-13

Small Business Award
Donlar Corporation
Production and Use of Thermal Polyaspartic Acid	14-15
    -  "•• •'• -           tttnfaps'-*?
Alternative Synthetic Pathways Award
Monsanto  Company
Catalytic Dehydrogenation of Diethanolamine  	16-17

Alternative Solvents/Reaction Conditions Award
The Dow Chemical Company
100 Percent Carbon Dioxide  as a Blowing Agent  for
the Polystyrene Foam Sheet Packaging Market	18-19

Designing Safer Chemicals Award
Rohm and Haas Company
Designing an Environmentally Safe Marine Antifoulant	20-21

                                                        /nfrodudion   \

         resident Clinton established the Presidential Green
         Chemistry Challenge to promote pollution prevention and
         industrial ecology in partnership with the chemical indus-
         try. In October 1995, the U.S. Environmental Protection
         Agency (EPA) Administrator Carol Browner announced the
 Presidential Green Chemistry Challenge Awards Program as an
 opportunity for individuals, groups, and organizations to compete
 for Presidential awards in recognition of fundamental breakthroughs
 in "cleaner, cheaper, smarter chemistry." Five winners are typically
 honored each year, one in each of the following categories:
 • Academia.
 • Small business.

 « The use of alternative synthetic pathways for green chemistry,
  such as catalysis/biocatalysis; natural processes, including photo-
  chemistry and biomimetic synthesis; or alternate feedstocks that are
  more innocuous and renewable  (e.g., biomass).

 • The use of alternative reaction conditions for green chemistry,
  such as the use of solvents that have a reduced impact on human
  health and the environment, or increased selectivity and reduced
  wastes and emissions.

 • The design of chemicals that are, for example, less toxic than current
  alternatives or inherently safer with regard to accident potential.
  This booklet presents the 1996 and 1997 Presidential Green
Chemistry Challenge Award recipients and describes their award-
winning technologies. The winners each demonstrate a commitment
to designing, developing, and implementing green chemical technolo-
gies that are scientifically innovative, economically feasible, and less
hazardous to human health and the environment. The Presidential
Green Chemistry  Challenge Program is looking forward to adding
next years winners to the growing list of chemists and chemical com-
panies who are on the cutting edge of pollution prevention.

                     1997 Winners

   Professor Joseph M. DeSimone, University of
    North Carolina at Chapel  Hill (UNC) and
      North Carolina State  University (NCSU)
Design and Application of Surfactants for Carbon Dioxide
           Professor Joseph M. DeSimone, UNC and NCSU
           Fred Hansen, Deputy Administrator, EPA

           "[Professor Joseph M. DcSimone's] develop-
            ments in basic science are already making
            an impact on technology. This award will
            send a significant signal to manufacturing
            industries that there are indeed alternative
            ways to process manufacturing that don't
            generate waste streams."

            —Dr. Edward Samulski, Chairman,
             Department of Chemistry, UNC

                                                1997 Academic Aware/
     t has been a dilemma of modern industrial technology that the
     solvents required to dissolve the environments worst contami-
     nants themselves have a contaminating effect. Now, new technolo-
     gies for the design and application of surfactants for carbon diox-
     ide (CO:), developed at UNC, promise to resolve, this dilemma.
   Over 30 billion pounds of organic and halogenated solvents are
 used worldwide each year as solvents, processing aids, cleaning
 agents, and dispersants. Solvent-intensive industries are considering
 alternatives that can reduce or eliminate the negative impact that sol-
 vent emissions can have in the workplace and in the environment.
 CO, in a solution state has long been recognized as an ideal solvent,
 extractant, and separation aid. CO2 solutions are nontoxic, nonflam-
 mable, safe to work with, energy-efficient, cost-effective, waste-mini-
 mizing, and reusable. Historically, the prime factor inhibiting the use
 of this solvent replacement has been the low solubility of most mate-
 rials in CO2, in both its liquid and supercritical (sc) states. With the
 discovery of CO, surfactant systems, Professor DeSimone and his
 students have dramatically advanced  the solubility performance
 characteristics of CO, systems for several industries.
   The design of broadly applicable surfactants for CO, relies on the
 identification of "CO2-philic" materials from which to build
 amphiphiles. Although CO2 in both its liquid  and supercritical states
 dissolves many small molecules readily, it is a  very poor solvent at
 easily accessible conditions (T< 100 °C and P< 300 bar) for many
 substances. As an offshoot of Professor DeSimones research program
 on polymer synthesis in CO,, he and  his researchers exploited the
 high solubility of a select few CO2-philic polymeric segments to
 develop nonionic surfactants capable  of dispersing high solids poly-
 mer latexes in both liquid and scCO2  phases. The design criteria they
 developed for surfactants, which were capable of stabilizing hetero-
 geneous  polymerizations in CO,,, have been expanded to include
 CO2-insoluble compounds in general.

  This development lays the foundation by which surfactant-
 modified CO, can be used to replace conventional (halogenated)
 organic solvent systems currently used in manufacturing  and
service industries such as precision cleaning,  medical  device fabri-
cation, and garment care, as well  as in the chemical manufacturing
and coating industries.

             Legacy Systems, Inc.
Coldstrip™, A Revolutionary Organic Removal and
            Wet Cleaning Technology
        Robert R. Matthews, President, Legacy Systems, Inc.
        Fred Hansen, Deputy Administrator, EPA

        "Green Chemistry is truly the triumph of inge-
         nuity, innovation, and science which together
         can preserve and protect the long-term sustain--
         ability of our environment and our economy."

         —Fred Hansen, Deputy Administrator, EPA

                                          '997 Small Business Aworrf.
        i or over 30 years, the removal of photoresists with Piranha
        solutions (sulfuric acid, hydrogen peroxide, or ashers) has
        been the standard in the semiconductor, flat panel display, and
        micromachining industries. Use of Piranha solutions has been
        associated with atmospheric, ground, and water pollution.
 Legacy Systems, Inc. (LSI) has developed a revolutionary wet pro-
 cessing technology, Coldstrip™, which removes photoresist and
 organic contaminants for the semiconductor, flat panel display and
 micromachining industries. Coldstrip™  uses only water and oxygen
 as raw materials.

   LSIs Coldstrip™ process is a chilled ozone process that uses only
 oxygen and water as the raw materials. The active product is ozone,
 which safely decomposes to oxygen in the presence of photoresist.
 Carbon dioxide, carbon monoxide, oxygen, and water are formed.
 There are  no high temperatures, no sulfuric acid, no hydrogen perox-
 ide, and no nitric acid, all of which cause environmental issues.
   The equipment  required for the chilled ozone process consists of
 a gas diffuser, an ozone generator, a recirculating pump, a water
 chiller, and a process vessel. The water solution remains clear and
 colorless throughout the entire process sequence. There are no parti-
 cles or resist flakes shed from the wafer into the water; therefore,
 there are no requirements for particle filtration.
   Using oxygen and water as raw materials replacing the Piranha
 solutions significantly benefits the environment. One benefit is the
 elimination of over 8,400 gallons of Piranha solutions used per year
 per silicon wet station and over 25,200 gallons used per year per flat
 panel display station. Additionally, the overall water consumption is
 reduced by over 3,355,800 gallons per year per silicon wafer wet
 station and over 5,033,700 gallons per year per flat panel display
 station. The corresponding water consumption in LSIs process is
 4,200 gallons per year and there is no Piranha use.
   In 1995, the  U.S. Patent Office  granted LSI patent 5,464,480
covering this  technology. The system has the lowest environmental
 impact of any wet resist strip process, eliminating the need for thou-
sands of gallons of Piranha chemicals and millions of gallons of
water a year.

            BHC Company
     BHC Company Ibuprofen Process
    Newt Williams, Vice President, Government Relations,
    Celanese Corporation
    Lynn R. Goldman, Assistant Administrator, Office of
    Prevention, Pesticides, and Toxic Substances, EPA
    "[The award-winning technology] provides
     an elegant solution to a pressing problem
     in bulk pharmaceutical synthesis—that is,
     how to avoid large quantities of solvents
     and wastes."

     —Steve Wachnowsky, Manager,
      Bulk Pharmaceutical Operations,
      Celanese Corporation

                             1997 A/ternafiVe Synffiefic Pathways Award   7
          HC Company has developed a new synthetic process to
          manufacture ibuprofen, a well-known nonsteroidal anti-
          inflammatory painkiller marketed under brand names
          such as Advil™ and Motrin™. Commercialized since
          1992 in BHCs 3,500 metric-ton-per-year facility in
 Bishop, Texas, the new process has been cited as an industry
 model of environmental excellence in chemical processing technol-
 ogy. For its innovation, BHC was the recipient of the Kirkpatrick
 Achievement Award for "outstanding advances in chemical engi-
 neering technology" in  1993.

   The new technology involves only three catalytic steps, with
 approximately 80 percent atom utilization (virtually 99 percent
 including the recovered byproduct acetic acid), and replaces technol-
 ogy with 6 stoichiometric steps and less than 40 percent atom utiliza-
 tion. The use of anhydrous hydrogen fluoride as both catalyst and
 solvent offers important advantages in reaction selectivity and waste
 reduction. As such, this chemistry is a model of source reduction, the
 method of waste minimization that tops EPAs waste management
 hierarchy Virtually all starting materials are either converted to prod-
 uct or reclaimed byproduct, or are completely recovered and recycled
 in the process. The generation of waste is practically eliminated.
   The BHC ibuprofen process is an innovative, efficient technology
 that has revolutionized bulk pharmaceutical manufacturing. The
 process provides an elegant solution to a prevalent problem encoun-
 tered fn bulk pharmaceutical synthesis (i.e.,  how to avoid the large
 quantities of solvents and wastes associated with the traditional stoi-
 chiometric use of auxiliary chemicals when effecting chemical
 conversions). Large volumes of aqueous wastes (salts) normally
 associated with such manufacturing are virtually eliminated. The
 anhydrous hydrogen fluoride catalyst/solvent is recovered and recy-
 cled with greater than 99.9 percent efficiency. No other solvent is
 needed in the process, simplifying product recovery and minimizing
 fugitive emissions. The nearly complete atom utilization of this
streamlined process truly makes it a waste-minimizing, environmen-
tally friendly technology.

               DryView™ Imaging Systems
            Kris Burhardt, Vice President, Technology Development,
            Lynn R. Goldman, Assistant Administrator, Office of
            Prevention, Pesticides, and Toxic Substances, EPA

            "The Presidential Green Chemistry
             Challenge Award...is indicative of Imation's
             commitment to develop solutions that not
             only meet our customers' needs, but also
             benefit society as a whole."

             —Kris Burhardt, Vice President,
              Technology Development, Imation

                   •/997 Aifernofive So?ve"-^/Readion Conc/rtions Award
         hotothermography is an imaging technology whereby a -.
         latent image, created by exposing a sensitized emulsion to
         appropriate light energy, is processed by the application of
         thermal energy. Photothermographic films are easily imaged
         by laser diode imaging systems, with the resultant exposed
 film processed by passing  it over a heat roll. A heat roll operating at
 250 °F in contact with the film wall produce diagnostic-quality
 images in approximately 15 seconds. Based on photothermography
 technology, Imations DryView™ Imaging Systems use no wet chem-
 istry, create no effluent, and require no additional postprocess steps,
 such as drying.

   In contrast, silver halide photographic films are processed by
 being bathed in a chemical developer, soaked in a fix solution,
 washed with clean water, and finally dried. The developer and fix
 solutions contain toxic chemicals, such as hydroquinone, silver, and
 acetic acid. In the wash cycle, this chemistry, along with silver com-
 pounds, is flushed from the film and becomes part of the waste
 stream. The resulting effluent amounts to billions of gallons of liquid
 waste each year.

   Significant developments in photothermographic image quality
 have been achieved that allow it to successfully compete with silver
 halide technology. During 1996, Imation placed more than 1,500
 DryView™ medical laser imagers, which represent 6  percent of the
 world's installed base. These units alone have eliminated the annu-
 al disposal of 192,000 gallons of developer, 330,000  gallons of
 fixer, and 54.5 million gallons of contaminated water into  the
 waste stream. As future systems are placed, the reductions will be
 even more dramatic.

  DryView™ technolog}' is applicable to all industries that  process
 panchromatic film products. The largest of these industries are med-
ical radiography, printing, industrial radiography, and military recon-
naissance. DryView™ is valued by these industries because  it sup-
ports pollution prevention  through source reduction.

          Albright & Wilson Americas
THPS Biocides: A New Class of Antimicrobial Chemistry
         Paul Rocheleau, President, Albright and Wilson Americas
         Lynn R. Goldman, Assistant Administrator, Office of
         Prevention, Pesticides, and Toxic Substances, EPA

         "We are thrilled to provide a product that is
          less harmful to the environment than
          traditional compounds, while offering
          superior performance."

          —Paul Rocheleau, Chief Executive,
           Albright & Wilson

                             i'??7 Des;vr'nq Safer Chemicals Award    \\
            onventional biocides, used to control the growth of
            bacteria, algae, and fungi in industrial cooling
            systems, oil fields, and process applications, are high-
            ly toxic to humans and aquatic life and often persist
            in the environment, leading to  long-term damage.
To address this problem, a new and relatively benign biocide,
tetrakis(hyHroxymethyl)phosphonium sulfate (THPS), has been
discovered by Albright & Wilson Americas.  THPS biocides repre-
sent a completely new class of antimicrobial chemistry that
combines superior antimicrobial activity with a relatively benign
toxicology profile. THPS's benefits include low toxicity low recom-
mended treatment level, rapid breakdown in the environment,
and no bioaccumulation. When substituted  for more toxic bio-
cides, THPS biocides provide reduced risks to both human health
and the environment.
  THPS is so effective as a biocide that, in most cases, the recom-
mended treatment level is below that which would be toxic to fish.
In addition, THPS rapidly breaks down in the environment through
hydrolysis, oxidation, photodegradation, and biodegradation. In
many cases, it has already substantially broken down before the
treated water enters the environment. The degradation products
have been shown to possess a relatively benign toxicology profile.
Furthermore, THPS does not bioaccumulate and, therefore, offers a
much reduced risk to higher life forms.
  THPS biocides are aqueoxis solutions and do not contain VOCs.
Because THPS is  halogen-free, it does not contribute to dioxin or
AOX formation. Because of its low overall toxicity and easier han-
dling when compared to alternative products, THPS provides an
opportunity to reduce the risk of health and safety incidents.
  THPS has been applied to a range of industrial water systems for  '
the successful control of microorganisms. The United States industrial
water treatment market for nonoxidizing biocides alone is 42 million
pounds per year and growing at 6 to 8 percent annually. There are
over 500,000 individual use sites in this industry category. Because of
its excellent environmental profile, THPS has already been approved
for use in environmentally sensitive areas around the world and is
being used as a replacement for the higher risk alternatives.

                           1996 Winners
                ACADEMIC AWARD
      Professor Mark Hollzapple, Texas A&M University
Conversion of Waste Biomass to Animal Feed, Chemicals, and Fuels
                Professor Mark T. Holtzapple, Texas A&M University
                Lynn R. Goldman, Assistant Administrator, Office of
                Prevention, Pesticides, and Toxic Substances, EPA
                "[The award-winning technology] is a very
                good example of where technology can be
                both environmental and profitable at the
                same time. Yon don't have to choose
                between those two."

                —Professor Mark T. Holtzapple, Texas
                  A&M University

                                             f 996 Academic Award   13
           family of technologies has been developed at Texas
           A&M University that converts waste biomass into ani-
           mal feed, industrial chemicals,  and fuels. Waste bio-
           mass includes such resources as municipal solid waste,
          .sewage sludge, manure, and  agricultural residues.
Waste biomass is treated with lime to improve digestibility. Lime-
treated agricultural residues (e.g., straw,  stover, bagasse) may be
used as ruminant animal feeds. Alternatively, the lime-treated bio-
mass can be fed into a large anaerobic fermentor in which rumen
micro-organisms convert the biomass into  volatile fatty  acid (ATA)
salts, such as calcium acetate, propionate, and butyrate. The VFA
salts are concentrated and may be converted into chemicals or
fuels via three routes. In one route, the VFA salts are acidified,
releasing acetic, propionic, and butyric acids. In a second route,
the VFA salts are thermally converted to ketones, such as acetone,
methyl ethyl ketone, and diethyl ketone. In a third route, the
ketones may be hydrogenated to their corresponding alcohols,
such as isopropanol, isobutanol,  and isopehtanol.
   The above technologies offer many benefits for human health
and the environment. Lime-treated animal feed can replace feed
corn, which is approximately 88 percent of corn production.
Growing corn exacerbates  soil erosion and requires intensive
inputs of fertilizers, herbicides, and pesticides, all of which conta-
minate ground water.

   Chemicals (e.g., organic acids and ketones) may be  produced
economically from waste biomass. Typically, waste biomass is
landfilled or incinerated, which  incurs a disposal cost while also
contributing to land or air pollution. Through the production of
chemicals from biomass, nonrenewable resources such as  petrole-
um and natural gas are conserved for later generations. Because
50 percent of U.S. petroleum consumption is now imported, dis-
placing foreign oil will help reduce the  U.S. trade deficit.
   Fuels (e.g., alcohols) produced from waste biomass have the ben-
efits cited above (i.e., reduced environmental impact from waste dis-
posal and reduced trade deficit). In addition, oxygenated fuels
derived from biomass are cleaner burning and do not add net car-
bon dioxide to the environment, thereby  reducing factors that con-
tribute to global warming.

             Donlar Corporation
Production and Use of Thermal Poiyaspartic'Acid
       Larry R Koskan, President, Donlar Corporation
       Lynn R. Goldman, Assistant Administrator, Office of
       Prevention, Pesticides, and Toxic Substances, EPA

       "Society wants chemical companies and other
        industries to develop environmentally
       friendly materials. When we answer that
        call and when there is an economic incen-
        tive to do so, everybody wins."
       "Response from our customers and friends
        throughout the chemical industry has been
        overwhelming, very gratifying, and, not to
        mention, good for our business."

       —Larry P. Koskan, President,
         Donlar Corporalion

                                         1996 Small Business Award   J5
               illions of pounds of anionic polymers are used each
               year in many industrial applications. Polyacrylic acid
               (PAC) is one important class of such polymers, but
               the disposal of PAC is problematic, because it is not
              I biodegradable. An economically viable, effective, and
 biodegradable alternative to PAC is thermal polyaspartate (TPA).
   Donlar Corporation invented two highly efficient processes to
 manufacture TPA for which patents have either been granted or
 allowed. The  first process involves a dry and solid polymerization
 converting aspartic acid to polysuccinimide. No organic solvents
 are involved during the conversion and the only byproduct is con-
 densated water. The process  is  extremely efficient—a yield of more
 than 97 percent of polysuccinimide is routinely achieved. The sec-
 ond step in this process, the  base hydrolysis of polysuccinimide to
 polyaspartate, is also extremely efficient and waste free.
   The second TPA production process involves using a catalyst
 during the polymerization, which allows a lower heating tempera-
 ture to be used. The resulting product has improvements in perfor-
 mance characteristics, lower color, and biodegradability. The catalyst
 can be recovered from the process, thus minimizing waste.
   Independent toxicity studies of commercially produced TPA have
 been conducted using mammalian and environmental models.
 Results indicate that TPA is nontoxic and environmentally safe. TPA
 biodegradability also has been tested by an independent lab using
 established OECD methodology. Results indicate that TPA meets
 OECD guidelines for Intrinsic Biodegradability. PAC cannot be classi-
 fied as biodegradable when tested under these same conditions.
   Many end-uses of TPA have been discovered, such as  in agricul-
 ture  to improve fertilizer or nutrient management. TPA increases
 the efficiency of plant nutrient uptake, thereby increasing crop
 yields while  protecting the ecology of agricultural lands.  TPA can
also be used for water treatment, as well as in the detergent, oil,
and gas industries.

          Monsanto Company
Catalytic Dehydrogenation of Diethanolamine
     Michael A. Pierle, Vice President, Environment, Safety, and
     Health, Monsanto Company
     Lynn R. Goldman, Assistant Administrator, Office of
     Prevention, Pesticides, and Toxic Substances, EPA
     "[The Presidential Green Chemistry Award] is
      an outstanding honor, one which we believe
      symbolizes the overall commitment of
      Monsanto people worldwide to reduce pollu-
      tion and create a more sustainable world."

      —Michael A. Pierle, Vice President,
       Environment, Safety, and Health,
       Monsanto Company

                           7 996 Alternative Synthetic Pathways Award   17
           4sodium iminodiacetate (DSIDA) is a key intermediate in
           the production of Monsanto's Roundup® herbicide, an
           environmentally friendly, nonselective herbicide.
           Traditionally, Monsanto and others have manufactured
           DSIDA using the Strecker process requiring ammonia,
formaldehyde, hydrochloric acid, and hydrogen cyanide. Hydrogen
cyanide is acutely toxic, and requires-special handling to minimize
risk to workers, the community, and the environment. Furthermore,
the chemistry involves the exothermic generation of potentially
unstable intermediates, and special care must be taken to preclude
the possibility of a runaway  reaction. The overall  process also gener-
ates up to I kilogram (kg) of waste for  every 7 kg of product, and
this waste must be treated prior to safe disposal.
   Monsanto has developed and implemented an alternative DSIDA
process that relies on the copper-catalyzed dehydrogenation ot
diethanolamine. The raw materials have low volatility and are less
toxic. Process operation is inherently safer, because the dehydro-
genation reaction is endothermic and, therefore, does not present
the danger of a runaway reaction. Moreover, this "zero-waste" route
to DSIDA produces a product stream that, after  filtration of the cat-
alyst, is of such high quality that no purification or waste cut is
necessary for subsequent use in the manufacture of Roundup®.
The new technology represents a major breakthrough in the pro-
duction of DSIDA, because it avoids the use of cyanide and
formaldehyde, is safer to operate, produces higher overall yield,
and has fewer process steps.
   The metal catalyzed conversion of aminoalcohols to amino acid
salts has  been known since 1945. Commercial application, howev-
er, was not known until Monsanto developed a series of propri-
etary catalysts that made the chemistry commercially feasible.
Monsanto's patented improvements on metallic copper catalysts
afford an active, easily recoverable, highly selective, and physically
durable catalyst that has proven itself  in large-scale use.     _   :
   This catalysis technology also can be used in  the production of
other amino acids, such as  glycine. Moreover, it is a general
method for conversion of primary alcohols to carboxylic acid salts,
and is potentially applicable to the preparation of many other
agricultural, commodity, specialty, and pharmaceutical chemicals.

             The Dow Chemical Company
      TOO Percent Carbon Dioxide as a Blowing Agent
      for the Polystyrene Foam Sheet Packaging Market
           Gary W. Krook, Global Director, Research and Development,
           The Dow Chemical Company
           Lynn R. Goldman, Assistant Administrator, Office of
           Prevention, Pesticides, and Toxic Substances, EPA

           "It is particularly significant to have Dow's com-
           mitment to the environment recognized by our
           peers in the chemical industry...This technology
           is testament that when we merge our environ-
           mental commitment with innovative chemistry,
           we can create results that benefit our customers
           and society."

           —David T. Buzzelli, Vice President and
             Corporate Director of Environment,
             Health, and Safety, The Dow Chemical

                1996 Alternative Solvents-Reaction Conditions Award   19
    n recent years the chlorofluorocarbon (CFC) blowing agents
    used to manufacture polystyrene foam sheet have been asso-
    ciated with environmental concerns, such as ozone depletion,
    global warming, and ground-level smog. Due to these envi-
    ronmental concerns, the Dow Chemical Company has devel-
oped a novel process for the use of 100 percent carbon dioxide
(CCh). Polystyrene loam sheet is a useful packaging material
offering a high stiffness-to-weight ratio, good thermal insulation
value, moisture resistance, and recyclability. This combination of
desirable properties has resulted in the growth of the polystyrene
foam sheet market in the United States to over 700 million
pounds in 1995. Current applications for polystyrene foam
include thermoformed meat, poultry and produce trays,  fast food
containers, egg cartons, and serviceware.
  The use of 100 percent. CO: offers optimal environmental perfor-
mance since COi does not deplete the ozone layer, does not con-
tribute to ground level smog, and will not contribute to global
warming since COi will be used from existing byproduct commer-
cial and natural sources. The use of COi byproduct from existing
commercial and natural sources, such as ammonia plants and natur-
al gas wells, will ensure that no net increase in global COa  results
from the use of this technology. COz is also nonflammable, provid-
ing increased worker safety. It is cost-effective and readily available
in food grade quality. COz also is used in such common applica-
tions as soft drink carbonation and food chilling and freezing.
  The use of Dow 100 percent COi technology eliminates the use
of 3.5 million pounds per year of hard CFC-12 and/or soft HCFC-
22. This technology' has been scaled from pilot-line to full-scale
commercial facilities. Dow has made the technology available
through a commercial license covering both patented and  know
how technology. The U.S. Patent Office granted  Dow two patents
for this technology (5,250,577 and 5,266,605).

          Rohm and Haas  Company
Designing an Environmentally Safe Marine Antifoulant
        Howard Levy, Vice President, Rohm and Haas Company
        Dr. Charles Tatum, Vice President, Rohm and Haas Company
        Lynn R. Goldman, Assistant Administrator, Office of
        Prevention, Pesticides, and Toxic Substances, EPA

        "The President's Green Chemistry Challenge

         Award has had a positive effect on our

         introduction of this new chemistry for
          -John C. Harrington,
           Global Commercial Manager,
           Biocides-Marine, Plastics,
           Rohm and Haas Company

                             !996 Designing Safer Chemicals Award    21
        oulirig, the unwanted growth of plants and animals on a
        ship's surface' costs the shipping industry approximately $3
        billion a year,' largely due to increased fuel consumption to
        overcome hydrodynamic drag. Increased fuel consumption
        contributes to pollution, global wanning, and acid rain.
   The main compounds used worldwide to control fouling are the
organotin antifoulants, such as tributyltin oxide (TBTO). While
effective, they persist  in the environment and cause toxic effects,
including acute toxicity bioaccumulation, decreased reproductive
viability, and increased shell thickness in shellfish. These harmful
effects led to an EPA special review and to the Organotin Antifoulant
Paint Control Act of 1988.  This act mandated restrictions on the  use
of tin in the United States,  and charged the EPA and the U.S. Navy
with conducting research on alternatives to organotins.
   Rohm and Haas Company searched for an environmentally
safe alternative to organotin compounds. Compounds from the
3-isothiazolone class were chosen as likely candidates and over
140 were screened for antifouling activity The 4,5-dichloro-2-n-
octyl-4-isothiazolin-3-one (Sea-Nine™ antifoulant) was chosen as
the candidate for commercial development.
   Extensive environmental testing compared Sea-Nine™
antifoulant to TBTO, the current industry standard. Sea-Nine™
antifoulant degraded extremely rapidly with a half-life of 1 day in
seawater and 1  hour in sediment. TBTO, on the  other hand,
degraded much more slowly, with a half-life in seawater of 9 days
and 6 to 9  months in sediment. Tin bioaccum'ulated, with bioac-
cumulation factors as high as 10,000 X, while Sea-Nine™
antifoulant's bioaccumulation was essentially zero. Both TBTO
and Sea-Nine™ were acutely toxic to marine organisms, but
TBTO had  widespread chronic  toxicity, while Sea-NinerM
antifoulant showed no chronic  toxicity. Thus, the maximum
allowable environmental concentration (MAEC) for Sea-NinerM
antifoulant was 0.63 parts per billion (ppb) while the MAEC for
TBTO was  0.002 ppb.
   Hundreds  of ships have been painted with coatings containing
Sea-NineIM  worldwide.  Rohm and Haas Company obtained EPA
registration for  the use  of Sea-Nine1M antifoulant, the  first new
antifoulant  registration in  over a decade.

       Additional information on the Presidential Green Chemistry
       Challenge program is available by calling EPA's Pollution
       Prevention Information Clearinghouse at 202 260-1023.
       Information is also available from Paul Anastas and Tracy
       Williamson of EPA's Industrial Chemistry Branch at
       202 260-2659, and via the Internet at