United States
Environmental Protection
Agency
Risk Reduction
Engineering Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S2-90/029 Aug. 1990
Project Summary
Development of a Data Base on
Chemical Migration from
Polymeric Materials
Rosemary Goydan, Andrew A. Hawkins, and Arthur D. Schwope
A data base was designed and
constructed to organize and access
data on the migration of chemical
substances from polymeric materials.
The data base was developed under
an Interagency Agreement between
the U.S. Environmental Protection
Agency (EPA) and the U.S. Food and
Drug Administration (FDA). The data
base will facilitate the thorough and
efficient review of chemical migration
data and enable the EPA and FDA to
maintain an up-to-date compilation of
such data.
The migration data base was
developed with the use of a
commercial software package,
Advanced Revelation81", and runs on
IBM personal computers and
compatibles. Data elements include
the identity of the polymer and
migrant(s), the experimental
conditions of the migration test, the
diffusion coefficient, the amounts
migrated as a function of time, and
the data source. Data extraction
guidelines and data base features for
data entry, editing, searching, and
reporting were developed based on
EPA/FDA operational requirements.
All data entered into the data base
were extracted from the published
literature and FDA indirect food
additive petition files. Migration data
were entered from 90 citations and
include data for approximately 26
polymers and 81 migrants and
adjuvants. A User Manual providing
"Mention of trade names or commercial products
does not constitute endorsement or
recommendation for use.
detailed user instructions was also
prepared.
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
Migration is the movement by diffusion
of low molecular weight molecules from a
polymeric material to an external phase.
Migrants may be additives to the
polymeric material that improve its
stability (e.g., an antioxidant) or that
impart desirable properties (e.g., a
plasticizer). Migrants may also be
monomers, oligomers, or other residues
of polymerization (e.g., catalysts).
Furthermore, migrants may be chemicals
that are absorbed by the polymer after
fabrication.
Migration of chemical additives is of
interest to the U.S. Food and Drug
Administration (FDA), which is
responsible for ensuring that materials
used for packaging foods do not
contribute levels of chemicals to foods
that may present a health risk. Migration
of chemical contaminants is of interest to
the U.S. Environmental Protection
Agency (EPA) because of health and
safety concerns of workers wearing
protective clothing (e.g., the slow release
of chemicals from chemical protective
garments that have not been fully
decontaminated). In addition, EPA is also
concerned with chemical migration from
polymeric materials as a potential source
of indoor air pollution and as a factor in
the containment of wastes at sites where
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polymers are used as waste containment
liners.
The objective of the report summarized
herein was to design, construct, and
document a computerized data base on
the migration of chemical substances
from polymeric materials. The effort was
performed under an interagency
agreement between the EPA and the
FDA to address both agencies'
requirements for access to chemical
migration data and to fundamental
parameters associated with migration
data (e.g., diffusion coefficients).
Data Base Design
The Initial requirements for the data
base focussed on the types of data to be
stored in the data base and the
capabilities for operation of the final data
base system. We first developed a
prototype system based on the definition
of the system requirements. The
applications development software
package was selected, and a prototype
capability for data entry and searching
was constructed. After the prototype was
reviewed by EPA and FDA, the fully
operational data base was developed and
delivered to them with a documented
data set, guidelines for further data
extraction, and a User Manual.
Data Elements
Each data record in the data base
contains a series of data elements or
fields that are required to fully define the
migration test and test results. The data
elements describe the data source, the
identity of the polymer formulation, the
chemical migrant(s), the experimental
conditions under which the migration test
was performed, the migration data, and
the diffusion coefficient when available.
Full reference citations identify the
source of the data. Each chemical and
polymer is identified by using data
elements for the CAS registry number as
well as by using several chemical names.
Data elements were also included to
report properties of the polymer
formulation (e.g., molecular weight,
density). Data elements describing of the
experimental conditions include the test
temperature, the extraction medium and
volume, the polymer surface area and
thickness, and the analytical detection
method and its sensitivity. The migration
test results are reported using data
elements for time, amount migrated, and
diffusion coefficient.
Each data element was categorized as
either essential or supplemental. Only
those migration data for which values
were reported for all of the essential data
elements are included in the data base.
This screening for essential data
elements was the only screening criteria
applied to the data. No analysis of data
quality in terms of accuracy or precision
was performed. Values of all replicate
measurements were, however, entered
into the data base so that data quality
assessments could be made in the future
if desired. The data base could be
expanded to include data elements that
address data quality.
Data Base Structure
Based on the definition of the data
base requirements and the data
elements, the data base structure was
defined (Figure 1). The hierarchy begins
with the data_ elements describing the_
citation or data source; these are then
related to multiple polymer formulations
for which migration data were measured.
The polymer formulation is related to the
polymer, the migrant and other adjuvants,
and the physical properties reported for
the formulation. The migrant is related to
multiple sets of experimental conditions
at which the formulation was tested. Each
set of experimental conditions is then
related to one set of migration test data
that includes multi-valued time and
amount migrated data elements, and the
diffusion coefficient.
Software Selection
Several commercial software packages
for IBM personal computers and
compatibles were reviewed for their
suitability to develop the data base
system. Advanced Revelation (Cosmos,
Inc., Bellevue, WA), a relational data base
application development package, was
selected based on the operational
requirements and the required data base
structure., , ...-. .«—:.-..-_,-.
Data Base Features and
Operation
The data base features and operation
are described in detail in the User
Manual. A summary of the features for
data entry, searching, and reporting and
for system maintenance is provided here.
All data base operations are menu-driven
and several function keys were defined to
simplify operation of the data base.
Data Entry
Data entry is performed with the use of
full-screen displays and overlay windows.
Separate data entry screens are provided
for entry of citations, polymer and
chemical identity information, polymer
formulations and properties, experimental
test conditions, and migration test data.
Movement through the series of entry
screens is controlled through the use of
function keys. Function keys also provide
data editing and deletion capabilities.
Option lists provide easy reference
during data entry for several data
elements that have common or restricted
values. Option lists are provided for the
polymer class, temperature, analytical
detection method, extraction medium
category, polymer property test method,
and data source indicator data elements.
Options lists are accessed by using a
function key and may be updated by
using the system maintenance capability.
Search and Report
Capabilities To "search The data base
and generate reports are also available
through a menu-driven format and full-
screen displays. A search routine allows
the user to define the search criteria
using combinations of the polymer,
chemical, temperature, and extraction
medium data elements. Options are
provided to review the search results on-
screen, print the search report, redefine
the search criteria, or perform another
search. The results of the search,
reviewed either on-screen or printed as a
report, are presented in a predefined
format.
Capabilities to perform other, user-
defined data base searches are made
possible through the use of Easy Writer,
the menu-driven report generation
capability that is part of the Advanced
Revelation software. Easy Writer is a full-
feature report generator that allows the
user to search the data base files using
any combination of data base elements
and to define customized report formats.
Ust Reports .-—~——
Three list reports are provided. The
first report generates a list of all citations
in the data base and allows the user to
specify either author or citation number
order. The second generates a list of all
chemicals in the database, and the third,
a list of all polymers. The chemical and
polymer list reports can be specified for
output in either CAS Registry number
order, CAS Registry name order, or
display name order. All list reports can be
directed to the screen, a printer, or a disk
file for output.
System Maintenance
System maintenance capabilities are
included to set-up and modify printer
definitions and to update the options lists.
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Data Source
Citation
Polymer
Formulation 1
Polymer
Formulation 2
Migrant 1
Migrant 2
Experimental
Condition 1
Experimental
Condition 2
Migration
Test Result 1
Migration
Test Result 2
Figure 1. Data base hierarchy.
User Manual
The User Manual describes the data
base capabilities and provides detailed,
step-by-step instructions for data base
operation. The manual documents the
data base elements and data extraction
guidelines and details instructions for
use of the present system.
Data Extraction and Entry
The data set in the final data base
system was extracted from published
literature sources and from FDA
indirect food additive petition files. At
the outset of the assignment, an EPA
Category IV Quality Assurance Project
Plan (QAPjP) was prepared describing
the project, the intended use of the
data base, the data base quality
objectives, and our mechanism for
ensuring the accuracy of mathematical
operations, data transcription, and entry
procedures. This quality assurance plan
was followed throughout the program.
Data extraction and entry efforts were
conducted according to a defined set of
data extraction guidelines or
procedures. The guidelines address
data conversion and calculation
procedures required for numeric data
Polymer
Formulation (n)
Migrant (n)
Experimental
Condition (n)
Migration
Test Result (n)
base fields. Character or alphanumeric
fields (e.g., the identity of the citation,
polymer, migrant, adjuvants, extraction
medium, and analytical detection
method) are not considered here
because they are directly transcribed
from the citation. Procedures for data
conversions and data calculations are
described below.
Data Conversion Procedures
All numeric .data base elements
require specific units for data entry.
Consequently, data extracted from
citations must be converted if reported
in other units. Generally, these
conversions were straightforward and
involved direct multiplication or division
by a constant. Conversion procedures
were documented for several common
units to the required units for each
numeric database element.
Data Calculation Procedures
In addition to data conversions,
extraction of some numeric data
elements required a calculation
procedure involving one or more other
parameters reported in the citation or
available from the general reference
literature. Calculation procedures are
described for the four data elements
that routinely require calculations to be
performed. These elements include the
amount of extraction medium, the
migrant detection level, the amount
migrated, and the diffusion coefficient.
Data Sources
The migration data extracted and
entered in the data base are from three
principal sources:
(1) Scientific journal articles,
(2)Project reports of studies
conducted by Arthur D. Little,
Inc., and the National Bureau of
Standards (NBS) under contract
to the FDA, and
(3)FDA indirect food additive
petition (FAP) files.
No migration data were generated
under this assignment.
A total of 95 citations were reviewed
during this assignment. Data were
extracted and entered from 90 of these
95 citations. Five citations were
rejected for entry because values for
data elements designated as essential
were not reported and/or could not be
calculated. For the 90 citations entered,
43 citations were scientific journal
articles, 10 were project reports of
studies conducted under contract to
the FDA, and 37 citations were FDA
indirect food additive petitions. The
screening and extraction of data from
the FDA petition files was conducted at
the FDA facilities in Washington, DC.
Table 1 summarizes the polymers,
using common names and CAS
Registry numbers, included in the data
base.
Conclusions and
Recommendations
The migration data base provides a
useful resource for both the EPA and
FDA in the area of migration and
diffusion in polymers. Migration data
from a broad range of literature and
other sources have been compiled in a
detailed and consistent format that
facilitates comparison and correlation.
The data base will enable the EPA and
FDA to thoroughly and efficiently
review chemical migration data and to
maintain an up-to-date compilation of
such data. The data base could
ultimately be used to develop models
or correlations to gain a better
understanding of the migration,
permeation, and decontamination of
polymeric materials.
-&-U. S. GOVERNMENT PRINTING OFFICE, 1990/748-012/20085
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We recommend that the extraction
and entry of available migration data
continue on a regular basis. Because the
development of the data base system
was the focus of this assignment only a
fraction of the published migration data
was reviewed and extracted. We also
recommend that a system for
characterizing the quality of the data
be implemented so that the user will
have an indication of the reliability of
the reported migration data.
The full report was submitted in
fulfillment of Contract No. 68-03-3293
by Arthur D. Little, Inc., under the
sponsorship of the U.S. Environmental
Protection Agency.
Tible t Summary of Polymers Included in Migration Data Base
CAS Registry
Number
Common Name
CAS Registry
Number
Common Name
9003563 Acrytonitrile-butadiene-styrene copolymer 977085565*
977036459' AcrylonitrilB-mBthylacrylate copolymer, nitrite rubber modified 25748372
25033362 Ethylerso propytene ethylldenenorbornene terpolymer 9011147
2S64014G Ettrylorte-l.4-cyclohBxylane diethytene terephthlate 9003070
9010791 Ethylene propylene copolymer 9003536
24337788 Ethylene-vinyl acetate copolymer 977085838"
577027330' High-densitypolyethylene _ __. .. _ .. . 9002862,
977027341' Low-density polyethylene 20000"
24937164 Nylon 12 9003547
25038544 Nylon 6 9003558
32131172 Nylon 66 9011067
9002817 Pofyfoxymethylane) copolymer 25038726
9003172 Potybutsdiene rubber 10009"
Polycarbonate resin
Polyethylene terephthalate polymer
Polymethylmethacrylate
Polypropylene
Polystyrene
Polystyrene, rubber-modified
- Polyvlnyl. chloride .-_i
PVC-PA-PVC-PU
Styrene-acrylonitrile copolymer
Styrene-butadiene-styrene block copolymer
Vinylidene chloride-vinyl chloride copolymer
Vinylidene chloride-methyl acrylate copolymer
Wax-coated paper
•No spocidc CAS Registry number available; sequence number assigned by FDA.
Rosemary Goydan, Andrew A. Hawkins, and Arthur D. Schwope are with Arthur
D. Little, Inc., Cambridge, MA 02140
Esperanza P. Renard is the EPA Project Officer (see below).
The complete report, entitled "Development of a Data Base on Chemical
Migration from Polymeric Materials," (Order No. PB 90-235 1021 AS; Cost:
$17.00, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Risk Reduction Engineering Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH45268 ^ , _.. ,_ ,,; .
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
BULK RATE
POSTAGE & ^EES PAID
EPA
PERMIT No. G-35
Official Business
Penally for Private Use $300
EPA/600/S2-90/029
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