United States
                 Environmental Protection
                 Agency
Risk Reduction and
Engineering Laboratory
Cincinnati, OH 45268
                 Research and Development
EPA/600/S2-91/018  June 1991
EPA        Project  Summary
                 Diaper  Industry Workshop
                 Report
                 Clyde Dial and George Wahl
                   This report is the product of a 1-day
                 workshop on the diaper industry that
                 was sponsored  by the U.S.  Environ-
                 mental Protection Agency (EPA).  Four
                 topics were covered during the work-
                 shop: public health and safety, recy-
                 cling, composting,  and  product life
                 cycle analysis.  The primary objective
                 of the workshop was to identify areas
                 within the diaper industry that  need
                 further research that will lead to mini-
                 mizing the negative effect that diapers
                 have on the environment.  This report
                 can be used by both the  private and
                 the  public sector  to pursue  such  re-
                 search.
                   This Project Summary was developed
                 by EPA's Risk Reduction Engineering
                 Laboratory, Cincinnati, OH, to announce
                 key findings  of the research project
                 that Is fully documented In a  separate
                 report of the same title (see Project
                 Report ordering Information at back).

                 Introduction
                   In  response to the recent heightened
                 concern about the effect that diapers have
                 on the environment, and as part of EPA's
                 continuing effort to transfer technical infor-
                 mation to the public, EPA held a 1-day
                 workshop on the diaper industry.  More
                 than 30 representatives from industry, gov-
                 ernment, consulting firms, and waste han-
                 dling companies came together to discuss
                 issues relating to diapers and to identify
                 areas needing further research. The work-
                 shop was not a forum for debating whether
                 disposable or reusable diapers were the
                 more environmentally sound choice.  The
                 topics discussed during the workshop were
public health  and  safety,  recycling,
composting, and product life cycle analy-
sis.
  The research needs defined during the
course of the workshop are detailed in the
report summarized here.  Both the private
and  the public sector can use  the full
report to select research projects  that will
lead to improving diapers and lessening
their negative effect on the environment.

Procedure
  The focus topics for the workshop were
selected for their  relevance to the diaper
industry and  to the research that EPA is
currently pursuing.  The  chosen partici-
pants represented diverse knowledge and
viewpoints about the current state of the
diaper industry:  the reusable and the
disposable diaper manufacturers; waste
haulers, recyclers, and composters; con-
sulting firms that have conducted life cycle
analyses of diapers; academia; and vari-
ous EPA offices.
  Each of the four sessions, one on each
of the focus issues, began with a brief
presentation  on the issue, was followed
by  a discussion  period,  and concluded
with a summary  of the  research issues
that the participants had identified during
the discussion period.
  The overviews and research needs are
summarized, by topic, below.   The re-
search needs  are limited to  the knowl-
edge of the  participants at the workshop
and  are not  meant to be comprehensive.
In addition, some of the issues discussed
in this report may have already been re-
searched,  but the workshop participants
were unaware of the research.
                                                                     Printed on Recycled Paper

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 Public Health and Safety

 Overview
   To open this session, Wayne Turnberg
 of the Washington State Department of
 Ecology gave a presentation on the Wash-
 ington State Infectious Waste Project. This
 study, which assessed the risk of human
 infectious  disease acquired during the
 course of disposal, concluded that human
 pathogens  are routinely introduced  into
 the  solid waste stream  from residential
 sources  including disposable diapers and
 from medical waste stream sources. Once
 in a properly operated  landfill, pathogens
 are not likely to migrate and  may become
 inactive.   No  evidence of human infec-
 tious disease from  infectious  agents
 present in  municipal solid waste landfills
 or the waste stream was identified based
 on the literature search conducted for the
 report.

 Research Needs
   Human exposure considerations as they
 relate to the diaper industry  must be fur-
 ther examined for a better understanding
 of the human  exposure aspects of  han-
 dling and processing soiled diapers to pro-
 vide ways to control such exposure.  Be-
 low  are  examples of creditable  informa-
 tion  that  should be obtained and distrib-
 uted.
   • A  study  is needed of  the  occupa-
     tional infection risk to waste workers
     and the source of that  risk.  Sero-
     logic  markers for hepatitis  B and
     other  appropriate  pathogens should
     be  employed.  This study  should
     identify risks associated with collec-
     tion,  handling,  and  processing  of
     these waste materials.
   • A study is needed of the captured
     aerosols found in the void spaces of
     closed receptacles (i.e., plastic trash
     bags) containing soiled diapers and
     the effect of these aerosols on hu-
     mans during handling and collection
     of these containers by reusable dia-
     per services.  Human  exposure to
     these aerosols  during  the launder-
     ing  of reusable diapers should be
     evaluated.  Exposure assessments
     during collection of  disposable dia-
     pers and  their handling during recy-
     cling or composting are needed.
   • An  epidemiological study is needed
     to determine any health risk associ-
     ated   with   recycling  or  with
     composting  practices of this solid
     waste.
  Additional public health  and safety re-
search not  related directly to human  ex-
posure should:
      examine the survivability of patho-
      gens in the reusable diaper wash
      process;
      evaluate different biocides used for
      sanitizing reusable diapers;
      define,  quantitatively, the sources of
      microorganisms that enter the waste
      stream, including human and animal
      wastes;
      determine  the need for biological
      testing  of landfills to monitor human
      pathogens; and
      study the macro effects of combin-
      ing sewage sludge with the munici-
      pal solid wastestream.
 Recycling

 Overview
   The first presentation, given  by  Nancy
 Eddy of Procter and Gamble, focused on
 the Seattle Diaper Reclamation Project.
 This is a cooperative effort among Procter
 and Gamble (manufacturer of disposable
 diapers), the Seattle Solid Waste Utility, a
 local diaper service, and Rabanco (a solid
 waste recycling firm). The goal is  to de-
 termine the technical and economic feasi-
 bility of recycling disposable diapers.
   During  the course of  the project, the
 potential market for reclaimed pulp, plas-
 tic, and absorbent gel  materials will  be
 determined, and the Seattle Solid  Waste
 Utility will complete an economic evalua-
 tion, which will be verified by an indepen-
 dent consulting firm. If recycling is deemed
 economically feasible, the project will  be
 turned over  to Rabanco for continuous
 processing of disposable diapers.   This
 project began in June 1990.
   The second presentation, given by Gerry
 Sheehan  of  Weyerhaeuser, focused  on
 Weyerhaeuser's  San  Diego  Recycling
 Project.  The goal of the project was to
 design a recycling process  that was eco-
 nomically feasible,  was insensitive to mar-
 ket fluctuations, required minimal capital,
 and required no major changes  in current
 consumer habits. The drawbacks revealed
 by the project included  contamination of
the recovered pulp with  absorbent gel
 material, high water usage, and costly de-
 livery  and pickup of diapers.  Future re-
 search efforts include proving that the re-
claimed pulp's purity is  not impaired be-
cause  of  gel  contamination, testing the
pulp for  composting, exploring low-cost
 methods for extracting gel, and investigat-
 ing ways  to include disposable diapers
from the retail trade in the collection pro-
gram.
 Research Needs
   Research related to improving the qual-
 ity of recycled diaper material should:
    •  determine the  impact of contamina-
      tion by gelling material on pulp qual-
      ity;
    •  explore low-cost methods for extract-
      ing gelling material;
    •  find methods to efficiently separate
      different types  of plastics;
    •  develop catalysts  that enhance the
      properties of co-mingled plastics;
    •  study the feasibility of reducing the
      diversity of plastic for diaper liners,
      bags, adhesive strips, and elastics;
    •  evaluate the effect of different col-
      lection and separation  methods on
      the cost of recycling and  consumer
      acceptance;
    •  conduct  material balances to deter-
      mine how  much reclaimed pulp and
      paper are actually returned  to  the
      market and  not discarded as  pro-
      cess waste;
    •  determine the energy requirement for
      reclamation; and
    •  include collaborative  efforts among
      the  EPA, the Department of Com-
      merce, the Food and Drug Adminis-
      tration,  and  the  General  Services
      Administration to examine which gov-
      ernment actions can selectively "pro-
      mote" use of reclaimed materials.

Composting

Overview
   The first presentation, given  by  Nancy
Healy of  Recomp,  focused  on the  St.
Cbud, Minnesota, Diaper Compost Project.
The goal  of this project was to demon-
strate the viability of composting dispos-
able diapers.   For this  project, the  per-
centage of diapers  entering  St. Cloud's
aerobic composting process was increased
from  approximately  2% to  7.6% of the
municipal  solid waste feed to magnify the
effects of disposable  diapers on  the
composting process.  Preliminary results
indicate that the compost produced in this
study did not differ from the normal com-
post produced at  the St. Cloud facility.
The plastic backsheets  from  the diapers
are not compostable and  were removed
during the composting process by screens
that  eliminate materials over 1.5  in. in
diameter.
   For  the  second presentation, Steven
Howard of Amerecycle provided an over-
view of the Sumpter County, Florida, Com-
post Facility. Before being composted, the

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municipal  solid waste goes through sev-
eral processes at this facility including seg-
regation of household  hazardous waste,
shredding, magnetic separation, metal de-
tection,  hand-sorting, and moisture addi-
tion. The waste is then placed in open-air
windrows.  Aeration and inoculation with
microorganisms are  used to promote
composting.   This facility  has not con-
ducted any specific studies on composting
diapers but has had no problems from the
diapers that are processed at the facility.

Research Needs
  Further  research in composting should:
   • conduct a systems study comparing
     composting with landfilling,
   • compare sewage sludge composting
     with   municipal   solid  waste
     composting,
   • perform pilot studies on the separa-
     tion of diaper materials,
   • examine how trace  impurities (like
     gel material) affect the quality of com-
     post material, and
   • determine the economic viability of
     composting.

  Other research  not  directly  related to
composting should:
   • compare aerobic and anaerobic deg-
     radation in a controlled landfill with
     an outlet provided to collect meth-
     ane, and
   • conduct feasibility studies on the de-
     velopment and use of a flushable
     diaper.
Product Life Cycle Analysis

Overview
  Jere Sellers of Franklin Associates pro-
vided an  overview of product life  cycle
analysis (PLA). PLAs must examine multi-
media factors  including energy use, natu-
ral resource use, the quality of air, water,
and land when determining the environ-
mental impacts of a product. Comparison
of products within a PLA must be fair and
unbiased. Franklin Associates is currently
doing a life cycle analysis on various dia-
per products for the American Paper Insti-
tute.
  Anthony  Montrone  of Arthur  D. Little
gave a presentation on his firm's PLA of
diapers.  The study examined the health,
environmental, and economic effects of
both reusable and disposable diapers.  The
study showed that both types  of diapers
negatively  affect the  environment.   Dis-
posable diaper manufacture and  use gen-
erate more municipal solid waste than do
reusable diapers.  Reusable diapers use
more energy and water and result in higher
levels of total air and water pollution.

Research Needs
  Research needs related to  life cycle
analysis centered on the need to provide
guidance on approaches  to conducting
these analyses and their use. Further life
cycle studies should:
   •  identify the variables that significantly
     affect the final results for all diaper-
     related life cycle analyses,
   •  determine where diaper-related life
     cycle  analysis should begin and  end,
     and
   •  use life cycle  analysis to find target
     areas that should be  changed to re-
     duce  the environmental  effects of
     both  single-use  and  reusable  dia-
     pers.

Summary Statement
  The diaper industry workshop focused
on four important issues: public health and
safety, recycling, composting,  and prod-
uct life cycle  analysis  techniques.  A ma-
jority of participants believed that the health
and safety  issues  related to diapers cur-
rently receive more public scrutiny than is
warranted.  They concluded that there is
probably no significant public health and
safety problems related specifically to dia-
per handling, recycling, or disposal in prop-
erly  operated  and  constructed  landfills.
Because diaper disposal is  a  highly vis-
ible public issue, however, more definitive
health and safety studies should be con-
ducted on the handling and processing of
diapers.  This would clearly enable public
health officials to define any health and
safety issues related  to diaper  handling
and  to  dispel unwarranted  fears about
health problems associated with diapers.
  The  issues related  to recycling  and
composting of diaper  materials focused
on how to make these technologies eco-
nomically viable.  The consensus of  the
participants was that the major issues re-
lated to recycling, beyond making it eco-
nomically feasible, were the  quality of  the
product and the acceptance of  recycled
materials in the marketplace.
  The  conclusion from the  PLA discus-
sion was that these techniques are  an
excellent  way to identify aspects  of a
product's  life  cycle  that can be  targeted
for further study.  Such studies would fo-
cus  on  ways  to  increase the  length of
product life, the reuse  of product materi-
als, or ways of producing the product that
result in less waste.
  Many  research needs were identified
during the course of this workshop. Fur-
ther investigation  into these research is-
sues by  both the private sector and  the
public sector  will  lead to opportunities to
lessen the adverse environmental impacts
of diapers and to improve the health and
safety  of  those  who  come  into contact
with diapers. Initiation of research projects
in this area by EPA is contingent on  the
Agency's priorities.
  The full report  was submitted in  fulfill-
ment of Contract No. 68-C8-0061 by Sci-
ence Applications International Corpora-
tion (SAIC) under the sponsorship of  the
U.S. Environmental  Protection Agency.
                                                                          .S. GOVERNMENT PRINTING OFFICE: IWI - S48-OM/40015

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   Clyde Dial and George  Wahl are with Science Applications International Corp.,
     Cincinnati, OH 45203.
   Mary Ann Curan is the EPA Project Officer (see below).
   The complete report, entitled "Diaper Industry  Workshop Report," (Order No.
     PB91-191262/AS; Cost: $15.00, subject to change) will be available only from:
           National Technical Information Service
           5285 Port Royal Road
           Springfield, VA 22161
           Telephone: 703-487-4650
   The EPA Project Officer can be contacted at:
           Risk Reduction and Engineering Laboratory
           U.S. Environmental Protection Agency
           Cincinnati, OH 45268
 United States
 Environmental Protection
 Agency
Center for Environmental
Research Information
Cincinnati, OH 45268
      BULK RATE
POSTAGE & FEES PAID
         EPA
   PERMIT No. G-35
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Penalty for Private Use $300
EPA/600/S2-91/018

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