Monday
October 6, 1997
II i
Part III
Environmental
Protection Agency
Announcement of the Draft Drinking
Water Contaminant Candidate List; Notice
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Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
ENVIRONMENTAL PROTECTION
AGENCY
P=RU-6904-7]|
Announcement of the Draft Drinking
Water Contaminant Candidate List
AGENCY: Environmental Protection
Agency (EPA).
ACTON: Notice.
SUMMARY: The Safe Drinking Water Act
(SDWA). as amended in 1996. requires
the Environmental Protection Agency
(EPA) to publish a list of contaminants
which, at the time of publication, are
not subject to any proposed or
promulgated national primary drinking
water regulation (NPDVVR). that are
known or anticipated to occur in public
water systems and which may require
regulations under the SDWA [section
1412(b)(l)]. The SDWA. as amended.
specifies EPA must publish the first list
of contaminants (Drinking Water
Contaminant Candidate List, or CCL)
not later than 18 months after the date
of enactment, i.e.. by February 1998,
and every five years thereafter. The
SDWA. as amended, also specifies that
the CCL must be published after
consultation with the scientific
community, and after notice and
opportunity for public comment.
Today's notice announces the draft CCL,
provides background on how it was
developed, and seeks comment on
various aspects of developing the final
CCL. The CCL will be the source of
priority contaminants for drinking water
research, monitoring, guidance
development, and for selection of
candidates for drinking water
regulation. The draft CCL includes 58
chemical and 13 microbiological
contaminants.
DATES: Submit comments on or before
Decembers, 1997.
ADDRESSES: Send written comments to
the Comment Clerk, docket number W-
97-11. Water Docket (MC4101). USEPA.
401 M. St., SW, Washington. DC 20460.
Please submit an original and three
copies of your comments and enclosures
(including references). Comments must
be received or postmarked by midnight
December 5,1997.
Commenters who want EPA to
acknowledge receipt of their comments
should enclose a self-addressed,
stamped envelope. No facsimiles (faxes)
will be accepted. Comments may also be
submitted electronically to ow-
docket*epamall.epa.gov. Electronic
comments must be submitted as an
ASCII file avoiding the use of special
characters and any form of encryption.
Electronic comments must be identified
by the docket number W-97-11.
Comments and data will also be
accepted on disks in WordPerfect in 5.1
format or ASCII file format. Electronic
comments on this notice may be filed
online at many Federal Depository
Libraries.
The full record for this notice has
been established under docket number
W-97-11, and includes supporting
documentation as well as printed, paper
versions of electronic comments. The
full record is available for inspection
from 9 to 4 p.m. Monday through
Friday, excluding legal holidays at the
Water Docket, Room M2616,
Headquarters, USEPA, 401 M. Street,
SW, Washington, DC. For access to
docket materials, please call 202/260-
3027 to schedule an appointment.
Additionally, a few critical pieces of the
record have been made available at each
Regional Office.
FOR FURTHER INFORMATION CONTACT: For
general information, please contact the
EPA Safe Drinking Water Hotline. The
toll-free number is 800-426-4791. For
specific information on the CCL and the
contaminant identification process,
please contact Ms. Evelyn Washington,
at the U.S. Environmental Protection
Agency, Office of Ground Water and
Drinking Water. Mailcode 4607,
Washington, DC 20460, phone: 202-
260-3029, fax: 202-260-3762. email:
washington.evelyn@epamail.epa.gov.
EPA Regional Offices
I. JFK Federal Bldg.. Room 2203. Boston. MA
02203. Phone: 617-565-3602, Jerry
Healey
H. 290 Broadway. Room 2432. New York, NY
10007-1866. Phone: 212-637-3880,
Walter Andrews
in. 841 Chestnut Street, Philadelphia, PA
19107. Phone: 215-566-5775r Jeff Hass
IV. 345 Courtland Street, NE, Atlanta GA
30365. Phone: 404-562-9480. Janine
Morris
V. 77 West Jackson Blvd., Chicago. IL 60604-
3507. Phone: 312-886-4239, Kim Harris
VI. 1445 Ross Avenue, Dallas. TX 75202.
Phone: 214-665-7150, Larry Wright
VH. 726 Minnesota Ave., Kansas City, KS
66101. Phone: 913-551-7410. Stan
Calow
Vm. One Denver Place, 999 18th Street, suite
500. Denver. CO 80202. Phone: 303-312-
6627. Rod Glebe
DC. 75 Hawthorne Street. San Francisco. CA
94105. Phone: 415-744-1884. Bruce -
Macler ..
X. 1200 Sixth Avenue. Seattle. WA 98101.
Phone: 206-553-1893. Larry Worfey
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Background
n. Draft Drinking Water Contaminant
Candidate List
Table 1. Draft Drinking. Water Contaminant
Candidate List
ITI. Identification of Contaminants for the
Draft Drinking Water Contaminant
Candidate List
A. Role of NDWAC Working Group
B. Microbiological Contaminants Identified
for the Draft CCL
Table 2. Initial List of Microorganisms
Developed by EPA for Consideration by
the Workshop on Microbiology and
Public Health
1. Protozoa
2. Viruses
3. Bacteria
4. Microbiological Indicators
5. Future Activities Planned for
Microbiological Contaminants and the
CCL
6. Possible Impacts From Other Regulatory
Activity
C. Chemical Contaminants Identified for
the Draft CCL
1. The Initial List of Chemical
Contaminants Considered
Table 3. Initial List of Chemical
Contaminants Considered during
Development of the Draft CCL
a. 1991 Drinking Water Priority List
b. Health Advisories
c. Integrated Risk Information System
d. Non-Target Analytes in Public Water
Supply Samples
e. CERCLA Priority List
f. Stakeholder Responses
g. Toxic Release Inventory
h. Pesticides Identified by Office of
Pesticide Programs
Table 4. Pesticides Deferred
i. Safe Drinking Water Hotline
Table 5. Contaminants Identified by the
Safe Drinking Water Hotline
j. Endocrine Disrupters
Table 6. Contaminants Identified as
Suspected of Endocrine Disruption
2. Development and Application of the
Criteria
a. Criteria for Occurrence
b. Criteria for Health
3. Additional Specific Contaminants
Included
a. Aldicarb. Aldicarb sulfoxide. and
Aldicarb sulfone
b. Nickel
c. Sulfate
IV. Contaminants on the CCL Which Are of
Specific Interest
A. Aluminum
B. MTBE
C.Organotins
D. Rhodamine WT
E. Sodium
F. Zinc
G. 2.6-di-tert-butyI-p-benzoquinone (DTBB)
H. Contaminants to be Considered as
Groups
I. Contaminants for Which Unregulated
Contaminant Data are or Will Be
Available
Table 7. Contaminants with Unregulated
Contaminant Monitoring Data
V. Request for Comment
A. Data and Research Needs
Table 8. Data Needs for Chemical
Contaminants Included on the Draft CCL
B. Perchlorate
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52195
VI. Development bf.the final Drinking Water
„ Contaminant Candidate List, the •'.:'•-
Contaminant Identification Method, and
the Contaminant Selection Process
VH.' Summary'of Other Related Activity
Required by the SDWA ". "
A. Contaminant Selection and Regulatory
, Determination
B. The National Contaminant Occurrence
Database ' ''
C. Unregulated Contaminant Monitoring
Regulation
,VTII. Summary of Concurrent Regulatory
Activity Required by the SDWA
A. Radon
B. Other Radionuclides
C. Arsenic
D. Sulfate
E. Disinfectants and Disinfection
Byproducts
IX. Other Requirements
X. References
Abbreviations Used in this Notice
AC WA-Association of California
Water Agencies
ATSDR—Agency of Toxic Substances and
Disease Registry
AWWARF—American Water Works
Association Research Foundation
CASRN—Chemical Abstract Services
Registry Number
CCL—Contaminant Candidate List
CDC-Center for Disease Control and
Prevention
CERCLA—Comprehensive Environmental
Response, Comprehensive and Liability
Act
CIM—Contaminant Identification Method
D/DBP—Disinfectants and Disinfection
Byproducts
DWEL-Drinking Water Equivalent Level
DWPL—Drinking Water Priority List
EDSTAC—Endocrine Disrupter Screening
and Testing Advisory Committee
EPA—Environmental Protection Agency
ESWTR—Enhanced Surface Water Treatment
Rule
FIFRA—Federal Insecticide, Fungicide, and
Rodenticide Act
FQPA—Food Quality Protection Act
GW—Ground Water
HA—Health Advisory
HSDB—Hazardous Substances Data Base
IARC—International Agency for Research on
Cancer
ICR—Information Collection Request
IESWTR—Interim Enhanced Surface Water
Treatment Rule
IRIS—Integrated Risk Information System
LTESWTR—Long-term Enhanced Surface
Water Treatment Rule
MCL—Maximum Contaminant Level
MCLG—Maximum Contaminant Level Goal
NAS—National Academy of Sciences
NCOD—National Contaminant Occurrence
Database
NDWAC—National Drinking Water Advisory
Council
NIPDWR—National Interim Primary Drinking
Water Regulations
NPDWR—National Primary Drinking Water
Regulations
NPL—National Priority List
NRC—National Research Council
OGWDW—EPA's Office of Ground Water and
Drinking Water
"OPP—EPA's Office of Pesticide Programs
OPPTS—EPA's Office of Pollution
Prevention and Toxic Substances
PWS—Public Water Systems '
RDA—Recommended Daily Allowance
RiD—Reference,Dose; '..' ; '
RQ—Reportable Quantity ...... ." ......
SAB—EPA's Science Advisory Board
SDWA—Safe Drinking Water Act ...'''
STORET—Storage arid Retrieval Database
.SWTR—Surface Water Treatment Rule
TRI—Toxic Release Inventory"
WHO—World Health Organization L
I. Background •-•-".
The Safe Drinking Water Act (SDWA),
as amended in 1996, requires the
Environmental Protection Agency (EPA)
to publish a list of contaminants that are
known or anticipated to occur in public
water systems, and which may require
regulations under the SDWA (section
1412(b)(l)). The SDWA, as amended,
specifies that EPA must publish this
first list of contaminants (Drinking
Water Contaminant Candidate List, or
CCL) not later than 18 months after the
date of enactment (i.e., by February
1998), and publish a CCL every five
years thereafter. The SDWA also
requires that the list of contaminants
include those which, at the time of
publication, are not subject to any
proposed or promulgated national
primary drinking water regulation
(NPDWR). The list must be published
after consultation with the scientific
community, including the Science
Advisory Board, after notice and
opportunity for public comment, and
after consideration of the occurrence
database established under section
1445(g). The unregu/ated contaminants
considered for the list must include, but
not be limited to, substances referred to
insertion 101(14) of the Comprehensive
Environmental Response,
Compensation, and Liability Act of 1980
(CERCLA), and substances registered
under the Federal Insecticide,
Fungicide, and Rodenticide Act
(FIFRA).
Prior to the 1996 Amendments, the
SDWA required the EPA to publish a
drinking water priority list (DWPL) of
contaminants every three years which
were known or anticipated to occur in
drinking water and which may have
required regulation under the SDWA. In
response to these previous amendments,
EPA published two DWPLs which
served as candidates for regulation. The
first DWPL was published on January
22, 1988 (53 FR 1892), and the second
was published on January 14, 1991 (56
FR 1470).
The 1996 Amendments to the SDWA
were developed and enacted during the
time of the Presidential initiative
intended to substantially improve the
existing regulatory system to move the
Nation toward a new and better
environmental management system for
the 21st century. During the two-year
period prior to the 1996 Amendments,
EPA developed a'National Drinking
Water Program Redirection Strategy
(EPA. 1996a) to (1) establish priorities
for setting safety standards based on
health risks and sound science; (2)
support strong, flexible partnerships
among EPA, States, local governments
and other stakeholders to protect public
health; and (3) promote effective
community-based source water
protection. The Redirection Strategy
provides an overall framework for the
development of the CCL, as well as for
other drinking water program activities.
The Agency believes the draft CCL
presented in today's notice is the result
of a commendable effort of screening a
larger set of contaminants to the subset
of those of most concern. The draft CCL
is a first step toward improving risk
assessment, strengthening science and
data, and achieving better decision-
making and future priority setting.
Today's notice announces the draft CCL,
provides background on how it was
developed, summarizes detailed
material available in the docket and
used to develop the list, seeks comment
on the methods used to develop the
draft CCL, and seeks comment on
developing the final CCL. The draft CCL
is designed to be responsive to each of
the requirements noted above of the
SDWA, as amended, and is consistent
with the goals of the redirection
strategy.
Today's notice is being published
pursuant to the requirement in section
1412(b)(l) that the CCL be subjected to
prior notice and opportunity for public
comment. The contaminants included
are not subject to any proposed or
promulgated national primary drinking
water regulation,1 are known or
anticipated to occur in public water
systems, and may require regulations
under the SDWA. During the
development of the draft CCL, the
Agency consulted with stakeholders,
including the National Drinking Water
Advisory Council's Working Group on
Occurrence & Contaminant Selection,
which includes microbiologists,
lexicologists, public health scientists,
and engineers, and with other members
of the scientific community including
the Science Advisory Board (SAB). The
Agency plans for a more in-depth
consultation with the SAB during the
1 With the exception of nickel, aldicarb and its
degradates, and sulfate, which are considered
special cases. Refer to later sections of this notice
for rationale for inclusion.
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Federal Register / Vol. 62, No. 193 / October 6. 1997 / Notices
fall of 1997. The occurrence database.
which Is to be established under section
1445(g) by August 1999. was not
considered since it is currently under
development; however, occurrence data
from other sources was considered.
The final CCL, after publication in
February 1998, will be the source of
priority contaminants for the Agency's
drinking water program. Priorities for
drinking water research, occurrence
monitoring, guidance development,
including the development of health
advisories, will be drawn from the CCL.
The CCL will also serve as the list of
contaminants from which the Agency
will make determinations of whether or
not to regulate specific contaminants.
This first CCL is largely based on
knowledge acquired over the last few
years and other readily available
information, but an enhanced, more
robust approach to data collection and
evaluation will be developed for future
CCLs.
II. Draft Drinking Water Contaminant
Candidate List
The following table includes the
contaminants, microbiological and
chemical, presented as the draft
Drinking Water Contaminant Candidate
List The contaminants were identified
as described by Section III of today's
notice. The contaminants in the table
are Identified by name and Chemical
Abstracts Service Registry Number
(CASRN). The draft CCL includes 58
chemical contaminants/contaminant
groups and 13 microbiological
contaminants.
TABLE 1.—DRAFT DRINKING WATER
CONTAMINANT CANDIDATE LIST
Chemical contaminants
1,1,2,2-tQlra-chtoroethane
1,2,4-trimetriyibenzene
1,1-dfchloro-elhane
1.1-dichlofo-propene
1,2-dIphenylhydrazine
1,3-dtahloropropane
TABLE 1— DRAFT DRINKING WATER TABLE 1.—DRAFT DRINKING WATER
CONTAMINANT CANDIDATE LIST— CONTAMINANT CANDIDATE LIST—
Continued Continued
CASRN
79-34-5
95-63-6
75-34-3
563-58-6
122-66-7
142-28-9
Chemical contaminants
1,3-Dichloropropene (telone or
1,3-D)
2,4,6-trichlorophenol
2,2-dichloro-propane
2,4-dichlorophenol
2,4-dinitrophenol
2,4-dinitrotoluene
2,6-dinitrotoluene
2,6-di-tert-butyt-p-benzoquinone
(DTBB)
2-methyl-Phenol (o-cresol) .......
Acetochlor
Acetone
Alachlor ESA (a degradation
product of alachlor)
Aldicarbs*
Aldrin
Aluminum
Atrazine-desethyl, a degrada-
tion product of triazines
Boron
Bromobenzene
Cyanazine
p-Cymene (p-isopropyltoluene)
DCPA mono-acid degradate
DCPA di-acid degradate
DDE
Diazinon
Dieldrin
Dimethoate
Disulfoton
Diuron
EPTC (s-ethyl-
dipropylthiocarbamate)
Fonofos
Hexachloro-butadiene
Isopropylbenzene (cumene)
Linuron .-..
Manganese
Methyl bromide
Methyl-t-butyl ether (MTBE)
Metolachlor
Metribuzin
Molinate
Naphthalene
Nickel*
Nitrobenzene
Organotins
Prometon
RDX
CASRN
Chemical contaminants
542-75-6
88-06-2
594-20-7
120-83-2
51-28-5
121-14-2
606-20-2
719-22-2
95-48-7
34256-82-1
67-64-1
309-00-2
7429-90-5
6190-65-4
7440-42-8
108-86-1
21725-46-2
99-87-6
887-54-7
2136-79-0
72-55-9
333-41-5
60-57-1
60-51-5
298-04--*
330-54-1
759-94-4
944-22-9
87-68-3
98-82-8
330-55-2
7439-96-5
74-83-9
1634-04^
51218-45-2
21087-64-9
2212-67-1
91-20-3
98-95-3
1610-18-0
121-82-4
CASRN
RhodamineWT
Sodium 7440-23-5
Sulfate*
Terbacil 5902-51-2
Terbufos 13071-79-9
Vanadium 7440-62-2
Zinc 7440-66-6
Microbiological Contaminants:
Acanthamoeba (guidance expected for
contact lens wearers)
Adenoviruses
Aeromonas hydrophila
Caliciviruses
Coxsackieviruses
Cyclospora cayetanensis
Echoviruses
Helicobacter pylori
Hepatitis A virus
Legionella (in ground water)
Microsporidia (Enterocytozoon & Septata)
Mycobacterium avium intracellulare (MAC)
Toxoplasma gondii
'Included on the CCL as special cases, not
subject to the criteria used to identify other
contaminants.
III. Identification of Contaminants for
the Draft Drinking Water Contaminant
Candidate List
Drinking water contamination
generally occurs from: (1) Contaminants
that find their way into drinking water
sources from industrial waste releases,
agricultural runoff, atmospheric
deposition, and other pollution sources;
(2) contaminants formed during the
treatment of water supplies (e.g.,
disinfection by-products); and (3)
materials used for treatment, storage,
and distribution of water. EPA has
considered all of these sources in
identifying microbiological and
chemical contaminants for this draft
CCL. Figure 1 provides a graphical
representation of how today's draft CCL
was developed.
BILLING CODE 656O-BO-P
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52197
Figure 1. Illustration of Decision Tool Used to Develop the Draft
Contaminant Candidate List
391 drawn from: 1991 DWPL, health
advisories, IRIS, CERCLA, TRI,
OPP Ranking, PWS data, Stakeholders,
SDWA Hotline, and literature
391
contaminants
including
25 microorganisms
262
chemical
contaminants
Criteria focused
on occurrence
in water at levels
of health concern,
or indications
of occurrence
(production,
release, coupled
with properties).
Health effects
concentrations
were used to
determine
significance
of occurrence.
additional
contaminants
sutfate, nickel,
and aldicarbs
21
solely suspected of
endocrine disrpution
Deferred
83
6 SDWA Hotline
77 duplicates, or regulated
Removed from consideration
Data & information
gathering & evaluation
using Criteria
Expert Panel
microbial
contaminants
29
chemical
contaminants
No data available
EPA sought input
from international panel
of professional
microbiologists. The
input was presented to
the Working Group
for review & approval.
143
chemical
contaminants
Not Recommended
for the List
based on data evaluation
35
pesticides
Deferred
71
contaminants
13 microbiological
58 chemical
BILLING CODE 6560-SO-C
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The National Drinking Water
Advisory Council's (NDWAC) Working
Group on Occurrence & Contaminant
Selection played an integral part in the
development of the CCL by providing
recommendations for the criteria, and
the contaminants for initial
consideration. Also, during the
development of the CCL. the Agency
sought the expertise of microbiologists
for input on microorganisms to include
on the CCL. The following sections
describe the role of the NDWAC
Working Group and describe the
approach used to develop the CCL for
microorganisms and chemical
contaminants.
A. Role of NDWAC Working Group
After enactment of the recent SDWA
amendments, and in keeping with the
redirection strategy. EPA held its first
stakeholder meeting on approaches to
developing CCLs on December 2 and 3,
1996 in Washington, D.C. Participants,
including public water system
professionals, state regulatory officials,
public health officials, environmental
groups and other stakeholders, with a
range of interests, explored issues
concerning the identification of
potential drinking water contaminants
for consideration for the first CCL as
well as the factors to consider for future
CCL development. One result of the
meeting was the recommendation that
the February 1998 CCL be the first topic
addressed by the NDWAC Working
Group on Occurrence & Contaminant
Selection.
In 1975. pursuant to the SDWA
[Section 1446(a)], NDWAC was
established under the Federal Advisory
Committee Act to provide practical and
independent advice, consultation, and
recommendations to EPA on the
activities, functions and policies related
to the SDWA. At its meeting held on
November 13 and 14.1996. NDWAC
decided that working groups should be
formed on the following subjects: Small
Systems Capacity Building; Operator
Certification; Source Water Protection;
Consumer Confidence Reports; Drinking
Water State Revolving Fund; and
Occurrence & Contaminant Selection.
The NDWAC Occurrence &
Contaminant Selection Working Group
has been integral to developing the
criteria and identifying contaminants for
the draft CCL published today.
At the recommendation of the
Working Group, the Agency sought
expertise on microbiological
contaminants and convened a workshop
of microbiologists. The input from the
workshop was adopted by the Working
Group for use in developing the draft
CCL. The approach used to identify
microorganisms for the CCL is
explained in more detail in section III.B.
In addition to microorganisms, the
Working Group developed
recommendations on chemical
contaminants. The recommendations
addressed which contaminants to
include for initial consideration, and the
criteria for use in determining which
contaminants should be included on the
draft CCL. The recommendations were
developed over a series of meetings with
the Working Group followed by the
endorsement by the full NDWAC. The
details concerning the contaminants
included for initial consideration, and
development and use the identification
criteria are contained in section III.C.
B. Microbiological Contaminants
Identified for the Draft CCL
On May 20-21, 1997, EPA utilized a
workshop on microbiology and public
health to develop a list of pathogens for
possible inclusion on the first CCL.
Taking part in this workshop were
invited experts representing academia,
EPA and other federal agencies, and the
water industry. In preparation, EPA
scientists prepared and distributed a list
of microorganisms for initial
consideration by workshop members
(see Table 2.). Inclusion of organisms on
this initial list was based on disease
outbreak data, published literature
documenting the occurrence of known
or suspected pathogens in water, and
other information. A summary of the
workshop proceedings is in the docket.
Table 2. Initial List of Microorganisms
Developed by EPA for Consideration by
the Workshop on Microbiology and
Public Health
Protozoa
Microsporidia
Toxoplasma
Cyclospora
Acanthamoeba
Naegleria
Isospora
Viruses
Hepatitis E
Astroviruses
Coxsackie/Echo viruses
Adenovirus 40/41
Norwalk virus and other caliciviruses
Rotavirus
Bacteria
Helicobacter pylori
Mycobacterium (MAC)
E. coli O157:H7
Aeromonas hydrophila
Pseudomonas aeruginosa
Acrobacter
Campylobacter
Algal Toxins
Anaebaena flos-aquae
Aphanizomenon flos-aque
Microcystis aeruginosa
Schizothrix calcicola
Workshop participants established a
set of baseline criteria for deciding
whether an organism should appear on
the CCL. These criteria were (1) public
health significance, (2) known
waterborne transmission, (3) occurrence
in source water, (4) effectiveness of
current water treatment, and (5)
adequacy of analytical methods.
Organisms on the EPA list mentioned
above, as well as other organisms that
arose during the discussions, were
evaluated against these criteria.
The CCL published today includes the
list of pathogens identified by the
workshop and subsequently adopted by
the NDWAC as recommendations for the
CCL. Algal toxins were considered to be
of minimal public health significance,
and therefore were not included on the
draft CCL. The following sections
identify the organisms selected, the
rationale for why a pathogen was
included on the CCL, and the rationale
why certain pathogens were not
included.
1. Protozoa
The following protozoa are included
on the CCL: Cyclospora cayetanensis,
Toxoplasma gondii, the two
microsporida—Enterocytozoon and
Septate, and Acanthamoeba. It is
recommended that EPA develop
guidance for controlling Acanthamoeba,
for individuals who wear contact lenses.
The rationale for their selection follows.
C. cayetanensis has caused
waterborne outbreaks in other countries
and one documented outbreak in the
U.S. Thus, it may be a significant public
health risk. Disease symptoms include
watery diarrhea, abdominal cramping,
decreased appetite, and low-grade fever
(Huang et al., 1995). In HW-infected
persons, the disease may be chronic and
constant (Soave and Johnson, 1995). The
occurrence of this organism in natural
waters and its animal host range are
unknown. However, C. cayetanensis is
transmitted by the fecal-oral route, and
so its presence in water is likely. The
morphology of C. cayetanensis suggests
that the organism is relatively resistant
to disinfectants, but due to its large size
(7-10nm in diameter) it may be removed
satisfactorily by filtration. Cyclospora is
included on the CCL because it has
caused waterborne disease outbreaks in
the U.S. and other countries.
Toxoplasma gondii causes a common
infection of mammals and birds, but the
complete life cycle only occurs in wild
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52199
and domestic cats. The organism infects
a high percentage of the human
population (50 percent in some areas of
the U.S.) but, while subclinical
infections are prevalent, illness is rare
(Fishback, 1992). However, illness may
be severe in fetuses and AIDS patients.
Symptoms include^ fever, swelling of
lymph glands in die neck, blindness and
mental retardation in fetuses, and
encephalitis in AIDS patients (Fishback,
1992). There have been two documented
outbreaks of toxoplasmosis—in Panama
and British Columbia—both linked
epidemiologically to drinking water.
Chlorination of unfiltered surface waters
is not effective against Toxoplasma
(Benenson et al., 1982). However, due to
their large size (Ilxl2nm), filtration
may be effective in controlling this
organism. Toxoplasma is included on
the CCL because it poses a significant
public health risk, can be transmitted
via the waterborne route, and because a
reasonable potential exists for
completing the needed research in the
next few years for controlling this
organism.
Microsporidia are a large group of
protozoan parasites that are common in
the environment and multiply only
inside cells (Cali, 1991). Five species of
microsporidia have been reported to
cause disease in humans, but only two
are significant in water: Enterocytozoon
bieneusi and Septata intesttnalis. Both
are common in people with AIDS
(Goodgame, 1996) and occur chiefly in
AIDS patients (Bryan, 1995), although
infections have been reported in
otherwise healthy persons (Weber et al.,
1994). Symptoms may include diarrhea
(sometimes severe and chronic), and
illness involving the respiratory tract,
urogenital tract, eyes, kidney, liver or
muscles (Bryan, 1995; Goodgame, 1996;
Cali, 1991).
Microsporidia that infect humans
produce small (l-5p.m), very resistant
spores (Waller, 1979; Cali. 1991). They
are shed in bodily fluids, including
urine and feces, and thus have a strong
potential to enter water sources.
However, no waterborne outbreak has
yet been reported and there is no
published evidence of waterborne
transmission. Chlorine is probably not
effective against microsporidia, given
that other protozoan spores (cysts,
oocysts) are resistant to chlorine. Thus,
effective filtration and watershed
control may be needed to control this
organism in drinking water. E. bieneusi
and S. intestinalis are included on the
CCL because they pose a significant risk
to immuno-compromised individuals
and may not be removed effectively by
filtration because of their small size (the
spores are somewhat smaller than
Cryptosporidium oocysts).
Acanthamoeba are a group of free-
living amoeba that are common in soil
and water, including drinking water
(Sawyer, 1989; Gonzalez de la Cuesta et
al., 1987). Some Acanthamoeba species
are pathogenic and can cause
inflammation of the eye's cornea
(especially in individuals who wear soft
or disposable contact lenses (Seal et al.,
1992)), and chronic encephalitis in the
immuno-compromised population
(Kilvington, 1990). To date, no case of
waterborne disease has been reported.
However, Acanthamoeba cysts are
relatively resistant to chlorine (De
Jonkheere and Van der Voorde, 1976).
Because drinking water is not a
suspected route of transmission,
workshop members did not include
Acanthamoeba on their list. However,
as stated above, the Workshop
participants and the NDWAC
recommend that EPA issue guidance to
educate the public about the potential
problem with contact lenses.
Two protozoa that were on the initial
list for consideration developed by EPA
(Naegleria fowleri, Isospara belli), and
two that were not (Entamoeba
histolytica, Blastocystis hominis) were
also considered by the workshop, but
were not included on the CCL. The
reasons for excluding them follow.
N. fowleri is a free-living amoeba,
about 8-15|im in size, found in soil,
water, and decaying vegetation.
Although it is common in many surface
waters, it rarely causes disease. All
disease incidents have been associated
with swimming in natural or manmade,
warm fresh waters; drinking water is not
a suspected route of transmission. The
route of infection is via inhalation rather
than by ingestion. For this reason, it was
not included on the CCL.
/. belli causes gastrointestinal illness,
primarily in AIDS patients and children.
There ha«e been rio documented cases
of waterborne transmission. However,
the organism is transmitted by the fecal-
oral route, so its presence in water is
possible. Filtration is probably effective
in removing /. belli oocysts, given their
large size (30xl2|j.m). This organism was
not included on the CCL because of the
lack of documentation on waterborne
transmission and the belief that not
enough is known about the organism for
developing potential regulations within
a three-year time-frame.
E. histolytica is not considered to be
a significant health problem in the U.S.
In contrast to the situation for Giardia
and Cryptosporidium, animals are not
host reservoirs for E. histolytica. Thus,
the potential for source water
contamination is relatively low,
especially if sewage treatment practices
are adequate. Moreover, the organism
has not caused a significant waterborne
disease outbreak since the early 1950s.
Thirdly, the cyst is large (10-15nm),
slightly larger than a Giardia cyst; thus.
filtration should be effective for
removing this organism. For these
reasons, this organism was not included
on the CCL.
B. hominis was not included on the
CCL because its clinical significance has
not been determined and very little is
known about its potential for
waterborne transmission or its
occurrence in water.
2. Viruses
The following viruses are included on
the CCL: caliciviruses, adenoviruses,
coxsackieviruses, echoviruses, and the
hepatitis A virus. The rationale for their
inclusion follows.
The caliciviruses are a common cause
of acute, but mild, gastrointestinal
illness in the U.S. Between 1980 and
1994, 14 waterborne disease outbreaks
with more than 9,000 associated cases
caused by the Norwalk virus and other
caliciviruses were reported. Thus, their
public health significance is high.
However, because adequate recovery
and assay methods for the caliciviruses
are not yet available, information about
the occurrence of these viruses in water
or the effectiveness of water treatment is
lacking. It is believed that current
research programs might fill the
research gap in the near-term to allow
development of regulations, if
necessary, to control this group of
organisms.
Most of the adenoviruses are
respiratory pathogens. However,
serorypes 40 and 41 are important
causes of gastrointestinal illness,
especially in children. However, all
types may be shed in the feces, and may
be spread by the fecal-oral route.
Although adenoviruses have been
detected in water, data on their
occurrence in water are meager. No
drinking water outbreaks implicating
these viruses have been reported. Both
the respiratory and gastrointestinal
adenoviruses are recommended for the
CCL because of their high public health
significance and data which suggest that
adenoviruses are relatively resistant to
disinfectants.
The coxsackieviruses are readily
found in wastewater and surface water,
and sometimes in drinking water (Hurst,
1991). Although they have not caused a
documented outbreak of waterborne
disease, coxsackieviruses produce a
variety of illnesses in humans,
including the common cold, heart
-------
52200
Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
disease, fever, aseptic meningitis.
gastrointestinal problems, and many
more, some of which can be serious
(Mdniek, 1992). Coxsackieviruses are
included on the CCL because they are
found more frequently in water than
other viruses and are associated with a
number of illnesses.
The echoviruses, like the
Coxsackieviruses, are readily detected in
water, including treated drinking water.
They are associated with milder
illnesses than the Coxsackieviruses. and
have not caused a documented
outbreak. Echoviruses are included on
the CCL because, like the
Coxsackieviruses, they are found more
frequently in water than other viruses
and are associated with a number of
Illnesses.
The hepatitis A virus has caused at
least 11 waterbome disease outbreaks of
infectious hepatitis since 1980.
Therefore, it has a high public health
significance. The virus has been found
in contaminated drinking water, and is
somewhat resistant to chlorination
(Peterson et al., 1983). For these reasons,
it is also included on the CCL.
Three viruses that were on the initial
list for consideration developed by EPA
(rotavlruses, hepatitis E virus, and
astroviruses) and two that were not
(picobivirna and picotrivirna) were also
considered by the workshop
participants, but were not included on
the CCL. The reasons for not including
them follow.
Rotaviruscs cause acute
gastroenteritis, primarily in children.
Almost all children have been infected
at least once by the age of five years
(Parsonnet, 1992), and in developing
countries, rotavirus infections are a
major cause of infant mortality.
Rotavlruses are spread by fecal-oral
transmission and have been found in
ambient water, ground water, and tap
water (Gerba etal., 1985; Gerba, 1996).
However, only a single waterborne
disease outbreak has been reported in
the U.S. and only several have been
documented outside the U.S. (Gerba et
al., 1985). Rotavlruses are readily
Inactivated by chlorine, chlorine
dioxide, and ozone, but apparently not
by monochloramine (Berman and Hoff,
1984; Chen and Vaughn. 1990. Vaughn
etal., 1986; 1987). Rotavlruses were not
Included on the CCL because they are
not regarded as an important public
health problem in the U.S., and because
of their vulnerability to disinfectants.
Hepatitis E virus is an important agent
of hepatitis in underdeveloped
countries, but apparently not in the U.S.
The virus is transmitted by the fecal-oral
route (Dreesman and Reyes, 1992) and
probably a majority of cases are
waterborne. Even though the disease is
apparently not a health concern in the
U.S., one investigation found that 21.3%
of blood donors in Baltimore were sero-
positive (Thomas et al., 1997).
suggesting previous exposure to the
organism. Infections are mild and self-
limiting except for pregnant women,
who have a fatality rate of up to 39%.
No data from disinfection studies have
been published. Hepatitis E virus was
not included on the CCL because it is
not regarded as a significant public
health threat in the U.S., and because
current sewage treatment practices are
judged sufficient to eliminate risk of
waterborne transmission.
Astroviruses are found throughout the
world and cause illness in 1-3 year old
children and in AIDS patients, but
rarely in healthy adults (Kurtz and Lee,
1987; Grohmann et al., 1993).
Symptoms are mild and typical of
gastrointestinal illness, but the disease
is more severe and persistent in the
severely immune-compromised.
Astroviruses are transmitted by the
fecal-oral route and have been detected
in water and have been associated
anecdotally with waterborne disease
outbreaks (Cubitt, 1991; Pinto et al.,
1996). The astroviruses were not
included on the CCL because of the
mildness of the illness and the lack of
adequate documentation about the
occurrence in water and potential as a
waterborne disease agent.
The picobivirna and picotrivirna
viruses are of public health significance
outside the U.S., and are not regarded as
being a waterborne problem in the U.S.
and are adequately removed from
effluent water by current sewage
treatment practices. Picobivirna and
picotrivirna viruses were not included
on the CCL for these reasons.
3. Bacteria
The following bacteria are included
on the CCL: Helicobacter pylori,
Legionella, Mycobacterium avium
complex, and Aeromonas hydrophila.
The rationale for their identification
follows.
H. pylori has been closely associated
with peptic ulcers, gastric carcinoma,
and gastritis (Peterson, 1991; Nomura et
al.. 1991; Parsonnet et al., 1991. Cover
and Blaser, 1995). Data about its
distribution in the environment are
scarce, but the organism has been found
in sewage (Sutton et al.. 1995) and has
been linked to ambient water and
drinking water by epidemiological tests
and other means (Klein et al., 1991;
Shahamat et al., 1992; Shahamat et al.,
1993; Hulten et al., 1996). The number
of people in the U.S. that have
antibodies against H. pylori, and thus
have been exposed to the organism, is
high. Helicobacter is thought to be
vulnerable to disinfectants. H. pylori is
included on the CCL because of its
public health significance in the U.S.
and the possibility of waterborne
transmission.
Legionella pneumophila and other
Legionella species cause Legionnaires
Disease (a type of pneumonia) and
Pontiac Fever (a mild, nonpneumonic
illness). Legionnaires Disease, which
has a 15% mortality rate, typically
results from the inhalation of aerosols of
water containing the organism.
Legionella are abundant and naturally
occurring in surface water; thus they are
not necessarily associated with fecal
contamination. They have also been
detected in ground water. Small
numbers can occur in the finished
waters of systems employing full
treatment (U.S. EPA, 1989b) and can
colonize plumbing systems, especially
warm ones. Aerosols from fixtures, such
as showerheads, may cause the disease
via inhalation. Aerosols from cooling
towers, hot tubs, and pools have also
caused a number of outbreaks. Direct
person-to-person spread has not been
documented (Yu et al., 1983). Ozone,
chlorine dioxide, and ultraviolet light
are effective in controlling Legionella,
but data for chlorine are inconsistent
(States et al., 1990). Legionella in
surface water are already regulated
under EPA's Surface Water Treatment
Regulations (40 CFR part 141, subpart
H). Legionella in ground water is
included on the CCL because of their
public health significance in the U.S.
and the possibility of waterborne
transmission via ground water.
Mycobacterium avium complex
(MAC; also known as the
Mycobacterium avium intracellulare
complex) is common in the
environment and can colonize water
systems and plumbing systems (du
Moulin and Stottmeier, 1986; du Moulin
et al., 1988). It is known to cause
pulmonary disease and other diseases,
especially in individuals with a
weakened immune system (e.g., AIDS
patients). Drinking water has been
epidemiologically linked to infections
in hospital patients (du Moulin and
Stottmeier, 1986). MAC is relatively
resistant to chlorine disinfection
(Pelletier et al., 1988). MAC is included
on the CCL because of its high public
health significance, its ability to
colonize on pipes, and its relative
resistance to chlorine.
Aeromonas hydrophila can cause
wound infections and septicemia in
people with a weakened immune
system, and some evidence suggests that
it causes gastrointestinal disease in
-------
Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
52201
healthy people. The organism is
common in water and is not necessarily
associated with fecal contamination. It
is vulnerable to disinfectants. A. •
hydrophila is included on the CCL
primarily because it is common in
source water.
Pseudomonas aeruginosa is a free-
living bacterium that is common in
water. People at risk include patients
with profound neutropenia, cystic
fibrosis, severe burns, and those with
foreign devices installed (Hardalo and
Edberg, 1997). The organism has also
caused numerous outbreaks of
dermatitis in recreational waters, e.g.,
pools, whirlpools, and hot tubs (Kramer
et al., 1996). Because of differing
opinions among the microbiologists
who participated in the workshop about
its public health significance and its
potential health risk via the waterborne
route, a decision could not reach on
whether to include P. aeruginosa on
their list. Rather, it was recommended
that EPA conduct a complete literature
search on the topic before the Agency
decides whether to include this
organism on the final list. The literature
search will be conducted prior to
publishing the final CCL.
Four bacteria that were on the initial
list for consideration developed by EPA
(Escherichia coll O157:H7,
Campylobacter, Arcobacter, and the
cyanobacteria) and four that were not
(Salmonella, Shigella, Vibrio choleras
and other Vibrio species, and Yersinia
enterocolitica) were also considered by
the workshop, but were not included on
the CCL. The reasons for excluding
them follow.
E. coliOl57:H7, Campylobacter,
Salmonella, Shigella, V. choleras, and
Y. enterocolitica have all caused
waterborne disease in the U.S. and are
regarded as significant health risks.
They were not included on the CCL
because current treatment practices
were deemed to be adequate in
controlling these organisms. Arcobacter
was not included on the CCL because its
health significance and the possibility of
waterborne transmission are unknown,
and because current treatment practices
were judged likely in controlling this
organism.
Cyanobacteria (also known as blue-
green algae) are generally not
considered an important health risk.
However, certain species may produce
neurotoxins (which affects the nervous
system), hepatotoxins (which affects the
liver), and other types of toxins which,
if ingested at high enough
concentrations, may be harmful. High
concentrations of toxins associated with
a bloom of Schizothrix calcicola may
have been responsible for an outbreak of
gastroenteritis in 1975 (Lippy and Erb,
1976). However, little evidence exists
that ambient levels found in most water
supplies pose a health risk to the normal
population. The cyanobacteria was not
included on the CCL because the
problem is thought to be best handled
through good watershed management
practices to prevent algal growth in
source waters.
4. Microbiological Indicators
Indicators of fecal contamination or of
pathogens were not addressed at the
workshop. EPA is involved, however, in
a project with the International Life
Sciences Institute to begin an evaluation
of which microbiological indicators are
most appropriate for various types of
environmental waters.. Currently, the
Agency uses total coliform bacteria as
the sole indicator of microbiological
drinking water quality.
5. Future Activities Planned for
Microbiological Contaminants and the
CCL
EPA is attempting to develop a more
formal framework for identifying,
selecting and prioritizing pathogens
(and their indicators) for research and
possible regulation, and for future CCLs.
To date, the identification of pathogens
for the CCL has been relatively informal.
In contrast, a more objective approach
for contaminant identification and
selection in the future may be based on
a numerical scoring procedure such that
contaminants with higher scores would
have greater priority for regulation,
research and guidance development
than those that have lower scores.
6. Possible Impacts From Other
Regulatory Activity
Pathogens that are included on the
final CCL, will be candidates for
regulatory control, guidance
development, and additional research
over the next five years. These
organisms may be controlled, however,
by regulations currently under
development such as the Enhanced
Surface Water Treatment Rule, the
Ground Water Disinfection Rule. If
pathogens on the CCL are determined to
be controlled by these regulations, they
will be withdrawn from the CCL.
C. Chemical Contaminants Identified for
the Draft CCL
As stated earlier, the NDWAC
Working Group on Occurrence &
Contaminant Selection played an
integral part in developing the draft CCL
presented in today's notice. At the
initial Working Group meeting held on
April 3-4, 1997, the Agency proposed a
number of lists of contaminants as a
logical starting point for developing the
draft CCL. Some lists originate from
other Agency programs, while others
were developed in anticipation of future
DWPLs. The Agency also proposed that
the initial list would need to be reduced
to a smaller list of priority contaminants
that would become the CCL.
In April, the Working Group
identified 32 contaminants thought to
be those most important for inclusion
on the first CCL, other contaminants for
initial consideration, and criteria to be
used to evaluate and screen all
contaminants initially considered.
During this April meeting, and two
subsequent meetings, held on June 23
and July 17, 1997, the Working Group
developed these recommendations
which were approved by the full
NDWAC, and subsequently adopted by
the Agency, to use in screening the
initial list to the contaminants to today's
draft CCL. Summaries of the meetings
are provided in the docket. The
following sections provide the rationale
for the initial list of contaminants
considered and a summary of the
development and application of the
criteria used to evaluate the
contaminants on the initial list to
develop the draft CCL;
1. The Initial List of Chemical
Contaminants Considered
Ten lists of chemical contaminants
were considered to be logical starting
points for developing the first CCL. Of
the ten, eight lists were ultimately
combined to serve as the initial list of
contaminants to be considered for the
CCL. Some contaminants appear on
more than one of the eight lists. The
initial list of contaminants considered,
as well as those eliminated or deferred
from consideration, are in Table 3. The
following sections provide a description
of each of the lists and the rationale
behind including it with, or excluding
it from, the initial list of contaminants
considered.
-------
52202
Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
TABLE 3.—INITIAL LIST OF CHEMICAL CONTAMINANTS CONSIDERED DURING DEVELOPMENT OF THE DRAFT CCL
Contaminant
CAS No.
Contaminant lists considered
1991
DWPL
(1)
Health
advisories
(2)
IRIS
(3)
PWS (4)
CERCLA
(5)
Stake-
holder
summary
list (6)
TRI list
(7)
OPP rank-
ing
(8)
Contaminants Identified as Initial Candidates for the CCL during April 3-4,1997 Working Group Meeting
Inorganics:
•yinft
Pesticides:
PittulafA
DCPA mono-add dogradate ....
EPTC (s«ethyl-dipropyith!o-car-
Pconiston •
T«rf»o/*H
Triazine degradation products
Organlcs:
Z-methyWhenoI (o-cresol)
Ethytono gtycol
Methyl ethyl ketone (MEK)
Methyl-t-butyl ether (MTBE) ...
Phono)
7429-90-5
7440-66-6
34256-82-1
2008-41-5
2921-88-2
1861-32-1
2136-79-0
887-54-7
72-55-9
333-41-5
330-54-1
115-29-7
759-94-4
121-75-5
298-00-0
51218-45-2
21087-64-9
1610-18-0
709-98-8
34014-18-1
5902-51-2
6190-65-4
1582-09-8
95-48-7
67-64-1
107-21-1
78-93-3
1634-04-4
98-95-3
108-95-2
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
-
•
•
•
•
•
•
•
•
•
•D
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Additional Contaminants Considered for the CCL
Inorganics:
Ammonia
Ammonium nitrate
Ammonium sulfamats
Ammonium sulfate
Boron
Carbon dlsutflde
Carbonyl sulflde
Cobalt
Hydrochloric add
Hydrogen fluoride
Manganese
Matam-sodlum
Molybdenum
Phosphoric add
Phosphorous
Sodium
Strontium
Vanadium
PeslicMes:
1,3-Dlchloropropene (telone or
|3*D)
2,4,5-T
2.4-DP
7664-41-7
6484-52-2
7773-06-0
7783-20-2
7440-42-8
75-15-0
463-58-1
7440-48-4
7647-01-0
7664-39-3
7439-96-5
137-42-8
7439-98-7
7664-38-2
7723-14-0
7440-23-5
7440-24-6
7440-62-2
542 75—6
QT_7R_/i
94-82-6
120-36-5
•
•
•
•
•
t/
^
•
•
•
•
•
•
•
•
•
•
t/
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
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Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
52203
TABLE 3.—INITIAL LIST OF CHEMICAL CONTAMINANTS CONSIDERED DURING DEVELOPMENT OF THE DRAFT CCL—
Continued
Contaminant
4-Nitrophenol (p-Nitrophenol) ..
Acephate
Acifluofen
Aldrin
Ametryn
Amitraz
Asulam
Bensulfuron methyl
Bentazon
Benzidine
Bromacil
Bromoxynil
Cadre
Caprolactum
Captan
Carbaryl
Carboxin
Chloramben
Chlorimuron ethyl
Chlorothalonil
Chlorsulfuron
Clopyralid
Cyanazine
Cyromazine
ODD
DDT
Diazinon — oxypyrimidine
Dicamba
Dichlobenil
Dieldrin
Dimethoate
Dimethrin
Diphenamid
Disulfoton
Endosulfan sulfate
Ethalfluralin
Ethofumesate . .
Ethoprop
Ethylenethiourea (ETU)
Fenamiphos
Fluazifop-p-butyl
Fluometuron
Fomesafen
Fonofbs
Halofenozide
Halosulfuron
Hexazinone
Imazamethabenz
Imazapyr
Imazaquin
Imazethapyr
Imidacloprid
Lactofen
Linuron
Maneb (ETU precursor)
MCPA
MCPP
Metalaxyl
Methazole
Metnomyl
Metsulfuron methyl
Molinate
MSMA
Napropamide
Nicosulfuron
Norflurazon
CAS No.
100-02-7
30560-19-1
50594-66-6
309-00-2
834-12-8
33089-61-1
3337-71-1
25057-89-0
92-87-5
314-40-9
1689-84-5
105-60-2
133-06-2
63-25-2
5234-68-4
133-90-4
90982-32-4
1897-45-6
64902-72-3
1702-17-6
21725-46-2
66215-27-8
72-54-8
50-29-3
1918-00-9
1194-65-6
60-57-1
60-51-5
70-38-2
957-51-7
298-04-4
1031-07-8
55283-68-6
26225-79-6
13194-48-4
96-45-7
22224-92-6
2164-17-2
72178-02-0
944-22-9
51235-04-2
81405-85-8
81335-37-7
81335-77-5
77501-63-4
330-55-2
12427-38-2
94-74-6
93-65-2
57837-19-1
20354-26-1
16752-77-5
74223-64-6
2212-67-1
2163-80-6
15299-99-7
27314-13-2
Contaminant lists considered
1991
DWPL
(D
•
•
•
•
•
•
•
•
•
•
•
•
•
Health
advisories
(2)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
IRIS
(3)
•
•
•
•
•
•
•
•
•
•
•
•
•
PWS(4)
CERCLA
(5)
•
•
•
•
•
•
•
Stake-
holder
summary
list (6)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
TRI list
(7)
OPP rank-
ing
(8)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
-------
52204
Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
TABLE 3.—INITIAL LIST OF CHEMICAL CONTAMINANTS CONSIDERED DURING DEVELOPMENT OF THE DRAFT CCL—
Continued
Contaminant
Paraquat
P0nd!m6thaHn
Primlsutfufon methyl ...
ProoamkJQ .* •
Propachlof
Pfopoxui* (Bavflon) .
Pyrfthfobac-Na
Rlmsuifuron ,
S0thoxydfm
Sulfomstucon m@thyl
Thlodlcarh
Triallate
Triasulfuron «.
Organlcs:
112 2"t6tf3-cnlofosthan6
1 1-dfchloro-6thanQ
1 2 3*tn*chloro-propanQ
1 ,2-diphQnyl-hydrazIn6 .
1 3-butadicna
1 3-dfchtoro*bon26n0
1 3-dJchforopropans
1 3*d!chtoropetan-3"-QL
1 4-dithiano
2,6-dl-tert-butyl-p-
benzoquinona (DTBB), (2,6-
bls{1,1-dlmethylethyl)2,5-
4,4'-Isopropy!idencdiphenoI
(blsphsnol A)
AcotsniklB
Acrylic add
Aovlonllrlle
CAS No.
4685-14-7
40487-42-1
7287-19-6
23950-58-5
1918-16-7
2312-35-8
139-40-2
122-42-9
60207-90-1
11 4-26-1
1698-60-8
74051-80-2
74222-97-2
13071 79-9
79277-27-3
59669-26-0
2303—17-5
82097-50-5
1929-77-7
630-20-6
79-34-5
75-34-3
563-58-6
96-18-4
95-63-6
122-66-7
108-70-3
106-99-0
541-73-1
142-28-9
99-65-0
123-91-1
505-29-3
872 50-4
594—20—7
88-06-2
120-83-2
51-28-5
121 14 2
606—20—2
719-22-2
109-86-4
107-05-1
80-05-7
106-44-5
75-07-0
60-35-5
75-05-8
79-10-7
107-13-1
1991
DWPL
(1)
•
t/
•
•
•
•
•
•
•
j/
•
!/
I/
•
Health
advisories
(2)
•
•
•
•
•
•
•
•
•
•
•
•
^
•
•
•
•
•
i/
j/
•
yf
•
c
IRIS
(3)
•
•
i/
•
•
i/
•
ontaminan
PWS (4)
•
•
i/
•
•
•
•
lists conside
CERCLA
(5)
red
Stake-
holder
summary
list (6)
•
•
•
•
•
•
TRI list
(7)
•
•
•
•
•
•
•
•
•
OPP rank-
ing
(8)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
-------
Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
52205
TABLE 3.—INITIAL LIST OF CHEMICAL CONTAMINANTS CONSIDERED DURING DEVELOPMENT OF THE DRAFT CCL—
Continued
Contaminant
Aniline
Azulene
Benzaldehyde
Benzaldehyde, 3-hydroxy-
Benzamide, N-acetyl-
Benzamide.N-ethyl-
Benzeneacetamide, N,N-di-
methyl-a-phenyl-
Benzeneacetonitrile
Benzofluoranthene
Bis-2-chloroisopropyl ether
Bornyl acetate
Bromobenzene
Catechol
Chlorodifluoromethane HCFC-
22
Chlorophenol 2-
Creosote
Cresol mixed isomers
Cymene p-(p-
isopropyltolunene)
Decabromodiphenyl oxide
Dibenzo(a,h)anthracene
Dichloro CFC-114
Dichloro-difluoromethane
DichloroHCFC141-b
Diethanolamine
Diisoamylene
Diisopropyl methylphosphonate
Dimethyl methylphosphonate ...
Diphenylamine
Ethanone, 1-[4-(hydroxy-1-
methylethyl) phenyl]-
Ethyl ether
Ethylene
Fog oil
Formaldehyde
Formic acid
Freon 113
Glufosinate ammonium
Glycol ethers
HCFC-11142-b
Hexachloro-butadiene
Hexachloroethane
Hexanoic acid
Hexazinone
HMX (cyclotetramethylene
tetranitramine)
Hydroperoxide, 1,1-
dimethylethy
lron,tricarbonyl-[n-(phenyl-2-
pyridinylmethylene)-benze
namide-N,N
Isophorone
Isopropylbenzene (cumene) ....
Isopropyl methyl-phosphonic
acid
Maleic hydrazide
Merphos oxide
Methane, tert-
butoxyisopropoxy-
Methanol
Methyl bromide
Methyl isobutyl ketone (MIBK)
Methyl methacrylate
Methylene bis
phenylisocyanate
CAS No.
62-53-3
275-51-4
100-52-7
100-83-4
1575-95-7
614-17-5
140-29-4
56832-73-6
39638-32-9
76-49-3
108-86-1
120-80-9
75-45-6
95-57-8
8001-58-9
1319-77-3
99-87-6
1163-19-5
53-70-3
76-14-2
75-71-8
171-00-6
111-42-2
1445-75-6
756-79-6
122-39-4
60-29-7
74-85-1
50-00-0
64-18-6
76-13-1
77182-82-2
111-46-6
87-68-3
67-72-1
142-62-1
51235-04-2
2691-41-0
175-91-2
78-59-1
98-82-8
1832-54-8
123-33-1
78-48-8
67-56-1
74-83-9
108-10-1
80-62-6
101-68-8
Contaminant lists considered
1991
DWPL
(1)
•
•
•
•
•
•
Health
advisories
(2)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
IRIS
(3)
•
•
•
•
•
PWS{4)
•
•
•
•
•
•
•
•
•
•
•
•
•
CERCLA
(5).
•
•
•
•
Stake-
holder
summary
list (6)
•
•
•
TRI list
(7)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
OPP rank-
ing
(8]
-------
52206
Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
TABLE 3.—INITIAL LIST OF CHEMICAL CONTAMINANTS CONSIDERED DURING DEVELOPMENT OF THE DRAFT CCL—
Continued
Contaminant
Other fuel oxygenates (TAME,
DIPE, ETBE) ,
oBtitanol « .
Nsphlnalend
NttfofllycfirioQ . .....
NttroQuankilns . .
OcUtriene. 3.7-dimethyl-1,3,6-
Organottns (trfbutyl, methyl tin,
.({•A
Rhodamlns WT ,.
RDX (cydo trimethyiene
Uifiltram!r>e)
Vinyl acetate
CAS No.
na
71-36-3
110-54-3
91-20-3
9004-70-0
55-63-0
95-49-8
13877-91-3
106-43-4
76-01-7
103-65-1
57-55-6
75-56-9
121-82-4
5915-41-3
109-99-9
509-14-8
75-69-4
25340-18-5
118-96-7
108-05-^
Contaminant lists considered
1991
DWPL
(1)
•
•
•
•
Health
advisories
(2)
•
•
•
•
•
•
•
•
•
•
•
•
•
IRIS
(3)
•
PWS (4)
•
•
•
CERCLA
(5)
Stake-
holder
summary
list (6)
•
•
•
•
•
•
TRI list
(7)
•
•
•
•
•
OPP rank-
ing
(8)
1.1991 Drinking water Priority List, but does not include disinfection by-products or crytosporidium for which regulations are being under the
M/DBP rules.
2. Health Advisories developed under EPA's Health Advisory Program. Does not include contaminants regulated under the SDWA.
3. Contaminants from IRIS Based on a risked-based screen developed by EPA.
4. Contaminants Identified In public water systems samples as non-targets.
5. First 50 contaminants of the 1995 ATSDR Ranked CERCLA priority chemicals list.
6. Stakeholder Summary List consists of specific contaminants proposed as candidates by participants of EPA's December 2-3, 1997 Stake-
holder Meeting on the Contaminant Identification Method.
7. The TRI Ust was derived from chemicals with significant health effects as found in IRIS.
8. The OPP Ranking Is a ranking of pesticides from highest to lowest potential to leach to ground water.
9. Stakeholders requested that the Agency address tirazines as a class of contaminants including their degradates, as opposed to addressing
them as Individual contaminants.
a. 1991 Drinking Water Priority List.
The SDWA, as amended in 1986.
required EPA to publish a triennial list
of priority contaminants, the DWPL,
which may require regulation. The first
list containing 53 contaminants/
contaminant group was published on
January 2.1988 (53 FR 1892). Since
none of the contaminants had been
selected for regulation, EPA revised and
updated the 1988 list three years later.
The revised and updated list, published
on January 14.1991 (56 FR 1470),
contained 50 substances carried over
from the 1988 list and 27 new
substances, bringing the total number of
contaminants/contaminant groups to 77,
including one microorganism.
In consideration of the statutory
requirements and the time frame for
rulemaking in the SDWA at the time,
EPA used the following criteria to select
contaminants for the DWPL: (1)
occurrence or the potential occurrence
of the substance in public water
systems; (2) documented or suspected
adverse health effects; and (3) the
availability of sufficient information on
the substance so that a regulation could
be developed within the statutory time
frame. The contaminants were selected
from the following groups: disinfectants
and their byproducts, the first group of
100 contaminants on the 1987 CERCLA
priority list of hazardous substances (52
FR 12866), design analytes of the EPA
National Pesticide Survey conducted
between 1987-1990. pesticides with
high potential for leaching in
groundwater, substances recommended
by the States and EPA regions,
unregulated contaminants monitored
under Section 1445 of the SDWA, and
certain substances reported frequendy
and at high concentrations in drinking
water. The selection of contaminants
was made widi the assistance of the
DWPL workgroup which consisted of
representatives from various programs
within the Agency, the National
Toxicology Program, the U.S. Geological
Survey, and the Agency for Toxic
Substances and Disease Registry.
For development of the draft CCL, the
Agency selected contaminants from the
1991 DWPL that were not specifically
addressed by other regulations under
development. Thus, all contaminants
specifically addressed by the
disinfectants and disinfection
byproducts regulation were eliminated
from consideration.
fa. Health advisories. The Health
Advisories (HAs) are prepared for
contaminants that have the potential to
cause adverse human health effects and
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Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
52207
which are known or anticipated to occur
in drinking water, but for which no
national regulations currently exist.
Each HA contains information on the
nature of the adverse health effects of
the contaminant and the concentrations
that would not be anticipated to cause
an adverse effect following various
periods of exposure. HAs also
summarize available data on
occurrence, pharmacokinetics,
environmental fate, health effects,
available analytical methods, and
treatment techniques for the
contaminant. HA concentration levels
include a margin of safety to protect
sensitive members of the population
(e.g., children, the elderly, pregnant
women).
The Office of Water Health Advisory
Program was initiated to provide
information and guidance to individuals
and agencies concerned with potential
risk from drinking water contaminants.
HAs are used only for guidance and are
not legally enforceable, and are subject
to change as new information becomes
available. For purposes of developing
the draft CCL, all contaminants with
HAs, or HAs under development, were
considered.
c. Integrated Risk Information System.
The Integrated Risk Information System
(IRIS) is an EPA on-line database
containing health risk and EPA
regulatory information. IRIS lists
chemicals of interest or concern for
which the Agency has reached
consensus regarding adverse health
effects. When available, a reference dose
(RfD) for non-cancer health effect
resulting from oral exposure is reported
with information about how the RfD
was derived and any uncertainty
regarding the source studies. An RfD is
an estimate of a daily exposure to the
human population that is likely to be
without appreciable risk of adverse
effect over a lifetime of exposure. For
carcinogens, a carcinogenic assessment,
or cancer potency factor, is reported for
both oral and inhalation exposure. The
cancer potency factor is the estimated
risk to the human population of cancer
effects over a lifetime of exposure.
In 1992, in anticipation of the next
DWPL, the Agency developed a list of
chemicals based on a risk-based screen
of chemicals in IRIS. There were
approximately 600 chemicals in the IRIS
database in 1992, and 312 were selected
for further screening. The 312 were
chosen because they had defined
toxicity via the oral route of exposure
and did not have NPDWRs. The 312
chemicals were screened using the
following categories: (1) using Storage
and Retrieval (STORET) data, chemicals
were identified with concentration in
water that exceeded the drinking water
equivalent level (DWEL) which was
derived from the reference dose or
cancer potency; (2) chemicals were
identified that were produced in
quantities exceeding one billion pounds
per year; (3) pesticides were identified
with use exceeding 1000 tons per year;
and (4) chemicals were identified that
were reported in the Toxic Release
Inventory (TRI) database as discharged
to surface water in excess of 100 tons
per year.,Sixteen chemicals met the
STORET criteria; nine, the production
criteria; 31, the pesticides criteria; and
6, the TRI criteria. A total of 48
individual chemicals were identified,
and some were identified by more than
one screen. All 48 contaminants were
included on the initial list for
consideration.
d. Non-Target Analytes in Public
Water Supply Samples, In anticipation
of the 1994 DWPL, the Agency
consulted with analytical laboratories
that routinely analyze samples for
public water systems to determine what
contaminants were occurring that were
not currently regulated. A list of
contaminants tentatively identified in
1991 from drinking water samples
collected for compliance monitoring
was developed. These contaminants,
also referred to as non-targets analytes,
are compounds identified by the spikes
found on the chromatograph. The
concentrations for these compounds
were not measured. These non-target
analytes represent the monitoring
experience of several water systems
with operations in various states. The
contaminants included on the initial list
for consideration are a subset of 23
contaminants chosen from the larger list
of non-targets analytes. The 23
contaminants were chosen because they
were considered to be related to
possible anthropogenic sources.
e. CERCLA Priority List. In developing
the CCL, the SDWA requires EPA to
consider substances referred to in
section 101(14) of the CERCLA.
CERCLA requires the Agency for Toxic
Substances and Disease Registry
(ATSDR) to prepare a list in the order
of priority of hazardous substances
which are most commonly found at
facilities on the CERCLA National
Priority List (NPL).
In 1995, ATSDR developed a list of
275 hazardous substances ranked by the
order of priority. (ATSDR, 1996) To
develop this list, ATSDR considered 750
of 2800 substances present at NPL sites
and ranked them based on the following
three criteria, which were combined to
result in a total score. These criteria
were: (1) Frequency of occurrence at
NPL sites, (2) toxicity, and (3) potential
for human exposure. The number of
NPL sites at which a substance was
identified in any medium was used to
indicate the frequency of occurrence.
EPA's Reportable Quantity (RQ) was
used to assess the toxicity of candidate
substance. If a RQ was not available, the
RQ methodology was applied to
candidate substances to establish a
Toxicity/Environmental Score. The
human exposure component was based
on two parts: the concentration of the
substance in the environmental media
and the exposure status of population.
EPA included the top 50 substances
from the 1995 CERCLA prioritized list
of 275 substances for consideration for
the draft CCL.
f. Stakeholder responses. In December
1996, the EPA convened its first
stakeholder meeting on the contaminant
identification process. At that meeting,
EPA requested input on what
contaminants to include on its first CCL.
At the December meeting, and
following, participants have provided
input to the Agency on contaminants for
inclusion on, or exclusion from, the
CCL. Some stakeholders provided
information on health effects or
occurrence, or both, while others listed
contaminants. All contaminants
suggested by stakeholders were
included for initial consideration except
those which already had NPDWRs, or
which were included under other
regulatory activity mentioned in section
VIII of this notice.
g. Toxic Release Inventory. Another
source of available information which
could serve as a predictor of anticipated
occurrence in drinking water, is the TRI.
This data base, established under the
Emergency Planning and Community
Right-to-Know Act of 1986, contains
information from manufacturing
facilities in the United States regarding
transfers and releases of toxic and
hazardous materials to air, ground and
water. The most recent report analyzed
data gathered for calendar year 1994
from 22 chemical categories and
included 343 separate chemicals from
23,000 facilities which met certain
thresholds requiring submission of data.
(U.S. EPA, 1997c).
In order to assess the potential for a
chemical to be a contaminant in public
water systems, EPA conducted an
analysis of the release and emissions
data. Each of the four categories of
emissions or discharges were assigned a
threshold value above which the
contaminant was deemed to fit within
the criteria of the SDWA, as a
contaminant anticipated to occur in
public water systems. The threshold did
not attempt to attribute differences in
reactivity, solubility, mobility or
-------
52208
Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
toxiclty of the pollutants at this stage of
the contaminant evaluation process, but
involved simply determining a gross
anticipation factor. If a contaminant was
released via an on-site discharge to the
environment. EPA judged that it was
reasonable to anticipate it as a
contaminant in public water systems to
varying degrees, depending upon the
media receiving the discharge.
The overall analysis of the above TRI
criteria resulted in 58 chemicals from
the various discharges meeting the
criteria. Where a release was close to the
threshold, it was included in the tally.
Several chemicals met the criteria but
were excluded because there is an
existing standard (e.g.. hydrofluoric
acid—fluoride is regulated) or a
standard under consideration (sulfuric
acid—there is regulatory activity
currently underway regarding sulfate).
Other contaminants such as ammonia,
hydrochloric acid, or methanol were not
believed to represent a significant threat
to drinking water due to limited
persistence, leaving 51 contaminants. Of
the 51 contaminants, 49 met the criteria
for air release, 21 from stack emissions,
38 for fugitive emissions, 11 via
underground injection, 13 from land
release, and 30 for surface water
releases. All 51 were included for initial
consideration in Table 3.
h. Pesticides Identified by Office of
Pesticide Programs, In developing the
CCL. the SDWA requires EPA the
consider substances referred to in the
F1FRA. During the development of the
draft CCL, the Agency's Office of
Ground Water and Drinking Water
sought assistance from the Office of
Pesticide Programs (OPP) in
determining what pesticides should be
priorities for the drinking water
program. In response to the request,
OPP provided recommendations for a
number of pesticides. (U.S. EPA, 1997b)
The list of pesticides, based on physical-
chemical properties, occurrence and
extent of use, was ranked using the
Ground Water (GW) Risk score, a
calculated potential to leach to ground
water. Pesticides with a GW Risk of 2.0
or greater were included for initial
consideration In developing the CCL
(see Table 3).
However, later during the data
evaluation and screening phase of the
draft CCL development, the decision
was made to defer some of the
pesticides identified by the OPP GW
Risk of 2.0 or greater. The pesticides in
Table 4 include those where the GW
Risk value of 2.0 or greater was the only
factor for inclusion on the CCL. The
decision was made, that for these cases,
inclusion on the CCL would be deferred
pending further evaluation of the
potential of these pesticides to occur at
levels of health concern. Many new
pesticides for which no other data exists
are included in Table 4.
Table 4. Pesticides Deferred
Asulam
bensulfuron methyl
bentazon
bromacil
Cadre
chlorimuron ethyl
chlorsulfuron
Diazinon—oxypyrimidine
Dicamba
Ethylenethiourea (ETU)
Fenamiphos
Fluometuron
Halofenozide
Halosulfuron
Hexazinone
Imazamethabenz
Imazapyr
Imazaquin
Imazethapyr
MCPA (Methoxone)
Methsulfuron methyl
Nicosulfuron
Norflurazon
Primisulfuron methyl
Prometryn
Propazine
Prosulfuron
Pyrithiobac-Na
Rimsulfuron
Sulfentrazone
Sulfometuron methyl
Tebufenozide
Terbufos sulfone
Thiazopyr
Triasulfuron
The Agency is working to develop a
tool to estimate concentrations in
ground and surface waters based on
physical-chemical properties and
pesticide use volumes, and then
compare the estimated concentrations
with health advisory levels or calculated
health levels based on reference doses
or cancer potency. The model is
expected to be completed and available
for use at the end of 1997, and at that
time the Agency will reevaluate the
inclusion for the additional pesticides
on Table 4 on the CCL. ,
On August 4,1997, EPA announced
its schedule for reassessing tolerances
for pesticide residues on raw and
processed foods (62 FR 42020).
Publication of this schedule was
pursuant to the requirements, as
established by the Food Quality
Protection Act of 1996 (FQPA). Under
this new law, EPA is required to
reassess all existing tolerances and
exemptions from tolerances for both
active and inert ingredients. EPA is
directed to give priority review to
pesticides that appear to present risk
concerns based on current data. Many of
the pesticides included in today's notice
are included among the first group of
reassessments.
In reassessing tolerances, EPA must
consider the aggregate exposure to the
pesticide, including drinking water;
cumulative effects from other pesticides
with a common mode of toxicity;
whether there is an increased
susceptibility from exposure to the
pesticide to infants and children; and
whether the pesticide produces an effect
in humans similar to an effect produced
by a naturally occurring estrogen or
other endocrine effects.
i. Safe Drinking Water Hotline. The
Hotline provides information about
EPA's drinking water regulations and
other related drinking water and ground
water topics to the public, the regulated
community, and State and local
officials. The Hotline assists callers with
questions on the regulations and
programs developed in response to the
Safe Drinking Water Act, and inquiries
about the levels and health effects of
specific contaminants found in or
suspected to be in drinking water from
public water systems and private wells,
and handles requests for drinking water
publications (fact sheets, pamphlets,
health advisories, etc.). The Safe
Drinking Water Hotline receives
hundreds of calls each week, and a large
percentage of the calls come from
private citizens, consultants, educators,
researchers, and health care
professionals from across the country.
The Hotline provided a list of
contaminants that were not currentiy
regulated or proposed for regulation for
which callers had expressed concern or
interest (see Table 5).
Table 5. Contaminants Identified by the
Safe Drinking Water Hodine
Calcium
Phosphates
1,1,1-dichloroethane
Gasoline
Perchlorate
Total Petroleum Hydrocarbons
The Hodine did not ascertain if die
calls were due to a general question or
inquiry, or if diey were related to a
contamination incident. At the April 3-
4,1997 Working Group meeting, the
decision was made not to include the
Hotline list for initial consideration, and
dial a list from the Hotline would only
be useful if it captured concerns or
reports of contamination.
The Agency will attempt to capture
Hodine inquiries concerning
contamination incidents for future CCL
development. Perchlorate, a
contaminant discussed later in this
notice, probably should have been
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Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
52209
Included for initial consideration. The
fact that perchlorate was on the Hotline
list, and no other, may indicate that
such a list from the Hotline could be
useful if the nature of the inquiry can be
recorded.
j. Endocrine disruptors. A list of
contaminants was developed which
included those suspected of having
adverse effects on endocrine function
(see Table 6). For several years, the
Agency has been concerned that
chemicals may be disrupting the
endocrine (i.e., hormonal) systems of
humans and wildlife. It has also been
hypothesized that endocrine disruption
might result in cancer, harm to male and
female reproductive systems, thyroid
damage, or other adverse consequences.
In February 1997, EPA issued an
assessment and analysis of this concern
(U.S. EPA, 1997a). The report represents
an interim assessment pending a more
extensive review expected to be issued
by the National Academy of Sciences
(NAS) later this year.
Table 6. Contaminants Identified as
Suspected of Endocrine Disruption
Amitrole
Benomyl
Dicofol (Kelthane)
Esfenvalerate
Ethylparathion
Fenvalerate
Kepone
Mancozeb
Metiram
Mirex
Nitrofen
Oxychlordane
Parathion
Permethrin
Synthetic pyrethroids
Transnonachlor
Tributyltin oxide
Vinclozolin
Zineb
Ziram
Octachlorostyrene
PBBs
Penta- to nonyl-phenols
In brief, the report found that while
effects have been found in laboratory
animal studies, a causal relationship
between exposure to a specific
environmental agent and an adverse
health effect in humans operating via
endocrine disruption has not been
established, with a few exceptions. The
exceptions include incidents of
chemical exposure in the workplace and
exposure to the drug DBS. Further
research is needed before such effects
can be demonstrated.
Under the SDWA, as amended, the
Agency is also required to establish a
program to screen endocrine disrupting
contaminants. Additional authority to
assess endocrine disruptors is also
provided through the recently enacted
FQPA. EPA's Office of Prevention,
Pesticides, and Toxic Substances
(OPPTS) has the Agency lead on
endocrine disrupter screening and
testing issues. OPPTS is actively
engaged in research and regulatory
initiatives to respond to the growing
scientific and public concern over
endocrine disruptors.
The Endocrine Disrupter Screening
and Testing Advisory Committee
(EDSTAC) has been established to
provide advice and counsel to the
agency in implementing a screening and
testing strategy required under the
FQPA and SDWA. EDSTAC is
composed of a balanced representation
from industry, government,
environmental and public health
groups, labor, academia, and other
interested stakeholders. During its
deliberations, the Committee will
consider human health, ecological,
estrogenic, androgenic, anti-estrogenic,
anti-androgenic, and thyroid effects of
pesticides, industrial chemicals, and
important mixtures. EDSTAC will
complete its recommendations for a
screening and testing strategy by March,
1998. The recommendations will be
peer reviewed jointly by the SAB and
the FIFRA Scientific Advisory Panel.
EPA is also involved in concurrent
effort to Coordinate activities with the
European Union, the Organization of
Economic and Community
Development, and the United Nations
Environmental Program concerning
global research programs, and
international harmonization of
endocrine disrupter screening and
testing methods for chemicals and
pesticides.
As a result, pending completion of the
EDSTAC's recommendations and the
additional review of endocrine
disruptors by the NAS, EPA has not
included contaminants for initial
consideration for the draft CCL based
solely on the possibility of endocrine
disruption (although several
contaminants implicated as endocrine
disruptors were considered for other
reasons). The Agency will .continue to
follow this issue closely and reconsider
this category of potential contaminants
in the development of future CCLs.
2. Development and Application of the
Criteria
Criteria were developed by the
NDWAC Working Group for use in
screening and evaluating chemical
contaminants for the draft CCL, with the
exception of aldicarbs, nickel, and
sulfate which are discussed in section
III.C.3. The general premises of the
criteria were: (1) The contaminants
included for initial consideration be
those on EPA's initial list, without
NPDWRs, and (2) that occurrence, or
anticipated occurrence, of the
contaminant be evaluated first, before
evaluating its health effects information.
The criteria, presented below, were used
to screen and evaluate chemical
contaminants for the purpose of
developing today's draft CCL. Data used
to evaluate and screen contaminants
were obtained from STORET, the
Hazardous Substances Database (HSDB),
IRIS, published literature, and various
EPA reports and documents. The data
used in the evaluation and screening are
included in the docket for today's
notice.
These criteria, as well as the
conceptual approach to the
Contaminant Identification Method
(CIM) presented in the December 2-3,
1996 Stakeholders meeting, will serve as
the basis for developing a more robust
contaminant identification method for
future CCL development. The search
results on each element of the criteria
for contaminants considered during the
development of the CCL can be found
by using the Occurrence Table, the
Health Table, and the Comments Table
included in the docket for today's
notice.
a. Criteria for occurrence. For the
occurrence portion of the criteria, an
affirmative response to any of the
following elements would result in
moving to the health portion of the
criteria for further consideration. If all of
the occurrence elements had a negative
response, the contaminant was
eliminated from further consideration.
The two main elements to the
occurrence portion of the criteria were
as follows: (1) Was the contaminant
looked for and found in drinking water,
or in a major drinking water source, or
in ambient water at levels that would
trigger concern about human health? (2)
if the contaminant was not looked for,
is it likely to be found in water based
on surrogates for occurrence?
To judge whether a contaminant was
looked for and found in drinking water,
according to the criteria, it would need
to be included in a major survey which
was defined as one which included a
population of 100,000 or more, 2 or
more states, or 10 or more small public
water systems, or a data set such as
EPA's Unregulated Contaminants
Database. To judge whether a
contaminant was looked for and found
in a major drinking water source, or in
ambient water, any source of occurrence
data could be used. A source of drinking
water was considered to be major if it
supplied a population of 100,000 or
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more, or 2 or more states. Levels that
would trigger concern about human
health were defined as concentrations in
samples within an order of magnitude of
the level that is likely to cause health
effects, or at least Vfe of samples at 50%
of level that is likely to cause health
effects. Contaminants were considered
to have met the criteria if the data
available indicated occurrence at a
population of 100.000 or more; or in 2
or more states; or in 10 or more small
public water systems at levels that
would trigger concern about human
health.
If the contaminant was not looked for
using the data available, it was
evaluated to determine if it was likely
to be found in water based on surrogates
for occurrence. The elements considered
as surrogates for occurrence included:
TRI releases, or production volumes,
coupled with physical-chemical
properties, or the OPP GW Risk value.
In order for a contaminant to meet this
criterion as Hkely to be found in water
using TRI, the release to surface water
was in excess of 400,000 pounds per
year, and the physical-chemical
properties indicated persistence &
mobility of the contaminant. The
quantity of 400,000 pound per year was
based on the top 15 TRI chemicals with
the largest discharges to surface water as
reported in 1995. In order for a
contaminant to meet this criterion as
likely to be found in water using
production, the volume was in excess of
10 billion pounds per year, and
physical-chemical properties indicated
persistence and mobility.
For a contaminant to meet this criteria
as likely to be found in water using OPP
GW Risk, the value was 2.0 or greater.
However, late during the data
evaluation and screening phase of the
CCL development, the decision was
made to defer contaminants identified
under this element until a more in-
depth analysis could be performed that
would include risk to both surface and
ground water, and a component to
address health.
b. Criteria for health. For the health
portion of the criteria, an affirmative
response to any of the following
elements resulted in including the
contaminant on the first CCL, if it also
met the occurrence criteria. A negative
response to every question resulted in
the contaminant being eliminated from
consideration for the CCL. The health
portion of the criteria had one major
component; was there evidence, or
suspicion, that the contaminant causes
adverse human health effects? This
portion of the criteria was met if a
contaminant had one or more of the
following elements: (1) Listed by
California Proposition 65, (2) an EPA
Health Advisory, (3) a likely (based on
animal data) or known (based on human
data) carcinogen by EPA or International
Agency for Research on Cancer (IARC),
(4) more than one human
epidemiological study (indicating
adverse effects), (5) an oral value in
IRIS, (6) regulated in drinking water by
another industrial country, (7) a member
of a chemical family of known toxicity,
or (8) structural activity relationship
indicating toxicity.
As the contaminants were being
screened and evaluated, the factors for
health which proved to be the most
useful were those that provided a health
level of concern as a concentration that
could be compared to the levels of
occurrence found in water, such as an
EPA Health Advisory, an oral value in
IRIS, or a regulatory level from another
industrial country. Being listed by
California Proposition 65, or a member
of a chemical family of known toxicity
had limited utility in determining
which contaminants to include on the
CCL.
3. Additional Specific Contaminants
Included
Aldicarbs, nickel, and sulfate are also
on the draft CCL. The SDWA. as
amended, did not specifically mention
aldicarbs and nickel, but since the
Agency has existing obligations for
completing regulatory action on these
contaminants pursuant to the SDWA, as
amended 1986, it was thought to be
prudent to include them on the CCL to
make clear the intention to address
these responsibilities. Sulfate is
included on the CCL, since the Agency
must make a determination to regulate
or not by August 2001, along with at
least four more contaminants. The
following sections provide the rationale
for the inclusion of aldicarbs, nickel,
and sulfate on the draft CCL.
a. Aldicarb, aldicarb sulfoxide, and
aldicarb sulfone. EPA promulgated a
final NPDWR for aldicarb, aldicarb
sulfoxide and aldicarb sulfone on July 1,
1991 (56 FR 30266). EPA set the
maximum contaminant level goal
(MCLG) at 0.001 mg/1 and maximum
contaminant levels (MCLs) of 0.003 mg/
1 for aldicarb, 0.004 mg/1 for aldicarb
sulfoxide. and 0.002 mg/1 for aldicarb
sulfone. In response to an
administrative petition from the
manufacturer Rhone-Poulenc, the
Agency issued an administrative stay of
the effective date of the MCLs, i.e., the
MCLs never became effective, but
monitoring is required. Rhone-Poulenc
also filed a petition for judicial review,
and the court stayed its proceedings
while EPA proceeded administratively,
but required quarterly reports. On
agreement of the parties, the judicial
proceedings have been dismissed. An
updated health advisory was issued in
1995 incorporating data from a human
study conducted in 1992 by Rhone
Poulenc. The aldicarbs were not subject
to the criteria used to identify other
chemical contaminants and are being
included on the CCL to signify the
Agency's intention to complete the
regulatory activity for these
contaminants. At this point, however,
the time frame of completing action
relative to aldicarbs has not been
determined.
fa. Nickel. NPDWRs for nickel
including an MCLG and an MCL of 0.1
mg/1 were proposed on July 25, 1990 (55
FR 30370) and finalized on July 17,
1992 (57 FR 31776). In September, 1992,
the Nickel Development Institute and
other industry parties filed a petition for
review in the U.S. Court of Appeals for
the B.C. Circuit challenging the MCLG
and MCL for nickel. The petitioners
raised objections over EPA's
methodology for determining the MCLG
for nickel. Specifically, they raised
questions concerning the derivation of
the relative source contribution factor
and the need for a 3-fold uncertainty
factor that EPA applied due to the lack
of adequate data on the effects of nickel
ingestion on reproductive systems.
Because the MCL for nickel was based
directly on the MCLG, the petitioners
also challenged the nickel MCL.
EPA and the petitioners entered into
discussions in an attempt to settle this
litigation but could not agree on the
merits of the petitioners' challenges.
Nevertheless, EPA agreed that it did not
fully address in the public record the
petitioner's comments on the proposed
methodology for deriving the MCLG for
nickel, and agreed to take a remand of
the MCLG and MCL for nickel.
Accordingly, on February 9, 1995, EPA
and the nickel industry petitioners filed
a joint motion for a voluntary remand of
the nickel MCL and MCLG. By orders of
February 23, 1995 and March 6, 1995,
the court granted this motion and
vacated and remanded the nickel MCLG
and MCL (and dismissed the lawsuit).
No other aspects of the NPDWRs for
nickel were vacated, including
monitoring requirements and
identification of best available
technologies for nickel. A notice of this
action was published in June 1995 (60
FR 33929).
To provide guidance for the period
prior to new regulations for nickel, the
EPA updated and issued a health
advisory for nickel. Nickel was not
subject to the criteria used to identify
other chemical contaminants and is
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52211
being included on the CCL to signify the
Agency's intention to complete
regulatory action for this contaminant.
The time frame of completing action on
nickel has not yet been determined.
c. Sulfate. As noted above, by August,
2001 the Agency must decide whether
or not to regulate sulfate. The date for
making a determination about sulfate
coincides with the date by when
determinations must be made for 5 or
more contaminants from the first CCL.
Sulfate was not subject to the criteria
used to identify other contaminants;
however, it has been included, given
these special circumstances.
IV. Contaminants on the CCL Which
Are of Specific Interest
A number of contaminants included
on the draft CCL may be of particular
interest. The following sections attempt
to provide additional information for a
few of the contaminants that seem to be
of most interest. Data obtained and
evaluated for developing the draft CCL
and referred to in the following
discussion can be found in the docket
for this notice.
A. Aluminum
There is intense interest from some
for development of drinking water
regulations for aluminum. Aluminum
currently has a secondary MCL of 50 to
200 "|ig/l based on organoleptic
properties. There have been a few
epidemiological studies in Canada that
emphasize the need to determine if
regulations for this contaminant should
be developed based on health effects. At
present, based on the work in Canada,
it appears that the most sensitive
population is the elderly. To determine
if aluminum is of health concern to the
elderly and to other possible sensitive
groups like children, the EPA
collaborated with Health Canada on a
workshop on aluminum held September
3 and 4, 1997. This workshop was
planned to help define the need for
chronic animal studies and the use of
appropriate animal models to better
characterize the risk of this contaminant
in drinking water. The Agency will
continue to work to determine if
aluminum is of health concern, and the
appropriate action to address this
concern.
B. MTBE
MTBE (methyl-t-butyl ether) is a fuel
additive used in many locations
throughout the United States to reduce
carbon monoxide and ozone forming
precursors associated with the
combustion of fossil fuels. There is
evidence of contamination of drinking
water; however the extent of
contamination of drinking water
supplies on a national scale is unclear
at this time (IAOF, 1997). The Agency
is in the process of revising the HA for
MTBE that will incorporate updated
health effects information, and has
completed a research strategy to guide
efforts at improving the understanding
of the occurrence and health effects of
MTBE (U.S. EPA, 1997e). As more PWSs
across the country voluntarily monitor
for MTBE, and if it is found at levels of
concern nationally, the Agency does
have the capacity to make a
determination to develop regulations to
monitor and/or control MTBE prior to
the 2001, SDWA deadline for selecting
at least 5 contaminants for
determination.
C. Organotins
Organotins represent a class of
contaminants which include, methyl
tin, tributyltin, and others. The
organotins of concern are those that
result from use in heat stabilizing PVC
piping for the in-home distribution of
water. There are a few cases of
tributyltin contamination of drinking
water in the U.S. (Sadiki, 1996). It has
been reported that the Canadian
government is concerned about
organotin contamination and has
planned a national survey of drinking
water in Canada to assess the danger to
human health.
The concentrations of concern for
human health are not known at this
time, however tributly tin and other
organotins are known to be toxic to
aquatic life. On August 7, 1997, the
Agency published a notice of ambient
water quality criteria document for
tributyltin (TBT) and a request for
comments (62 FR 42554). Ambient
water quality criteria are for the
protection of aquatic organisms and
guidance to States and others, and may
form the basis for enforceable State
water quality standards developed
pursuant to Section 304 (a) (1) of the
Clean Water Act.
D. Rhodamine WT
Rhodamine WT is a fluorescent dye
widely used as a tracer to measure
ground water flow. Rhodamine WT has
been certified by the National Sanitation
Foundation for use in tracing water
under the conditions that it not exceed
concentrations in drinking water of 0.1
|ig/l and that exposure be infrequent.
Rhodamine WT was detected in ground
water above the 0.1 [ig/1 value; however
the conditions under which the
detections occurred are unclear.
Rhodamine WT appears to be a
contaminant that the Agency may need
to observe more closely in terms of its
health effects, and possible occurrence
in drinking water.
E. Sodium
At present, the Agency has no
NPDWR or HA value for sodium. All
that is currently available is a guidance
DWEL of 20 mg/1. DWELs are
unenforceable guidance levels
describing a lifetime exposure
concentration of a contaminant that is
considered protective of adverse non-
cancer health effects, and it also
assumes that all of the exposure to a
contaminant is from a drinking water
source. In addition, EPA has a non-
enforceable criterion for dissolved
solids and salinity for ambient waters of
250 mg/1.
The DWEL is based on a 1965
American Heart Association
recommendation of a 20 mg/1 sodium
level to protect genetically susceptible
people on low sodium diets, assuming
a total dietary intake of 500 mg/day.
Naturally occurring sodium in food with
no salt added averages about 440 mg/
day. The additional 60 mg that would
increase the intake to the typical level
for a restricted diet of 500 mg/day must
take into account all other non-food
sources, such as drugs, water, etc. A
concentration in drinking water of up to
20 mg/1 of sodium is compatible with
this diet.
Since a significant percentage of the
U.S. population is attempting to reduce
their sodium intake, the Agency
believes that sodium levels in drinking
water could be an important issue. This
is particularly true for locations where
many of the residents using the water
may be susceptible to adverse health
effects from exposure to this
contaminant. The Agency believes that
all consumers are able to use water for
drinking if the sodium concentration is
maintained at or below 20 mg/1, but
nearly half of the nation's water
supplies have natural or added sodium
above these levels.
The inclusion of sodium on the CCL
is controversial, but it is expected that
guidance will be developed for those
who need it, and that including it on the
CCL will be a mechanism to develop an
Agency position on the issue of sodium
in drinking water.
F. Zinc
Zinc is used as a dietary supplement,
main ingredient in lozenges, and
corrosion inhibitor. There is intense
interest over including zinc on the CCL,
but there are also indications of health
effects associated with increased levels
of zinc consumption.
The Agency is aware that zinc is an
essential element for which the Food
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and Nutrition Board of the National
Research Council has established a
Recommended Dietary Allowance
(RDA). Zinc can also cause adverse
health effects at high doses and the zinc
RID (0.3 mg/kg/day) is higher than the
RDA for adult men and women. While
deriving RfDs, EPA must also keep in
mind the fact that excess exposure to an
essential trace element, such as zinc.
can also cause adverse health effects.
The present RfD for zinc represents a
balance between the essential
requirement for zinc and the toxic
effects of too much zinc; however, the
Agency is currently working on revising
the risk assessment procedures for
essential elements. The World Health
Organization (WHO) is also in the
process of developing a document on
the risk assessment of essential trace
elements, and EPA will consider the
WHO document when it is available.
G. 2,6-dl-tert-butyI-p-benzoqiiinone
(DTBB)
DTBB is a contaminant that appears to
be associated with sewage
contamination of ground water. A
ground water study concluded that
DTBB was a good indicator of such
contamination because, among other
reasons, it does not biodegrade readily
(Barber. 1988). DTBB was determined
not to meet the criteria for the draft CCL
per se, but was included nevertheless.
because of the recalcitrant nature of the
contaminant, its association with
sewage contamination, its potential
health Impacts, and its potential to serve
as an indicator of other contamination.
H. Contaminants to be Considered as
Croups
Stakeholders, through the regulatory
reassessment process and the
development of this draft CCL, have
requested that the Agency, address
triazlne pesticides as a group which
Includes all parent and degradates
compounds as opposed to each triazine
as an individual contaminant. The
triazlne pesticides include; cyanazine.
propazine, etc., and atrazine and
slmazine (which are both currently
regulated), and are often substituted for
one another for similar agricultural use.
The USEPA regulated atrazine in 1991
and simazine in 1992. Cyanazine and
atrazine-desethyl, a degradation product
of trlazines. were identified for the draft
CCL using the criteria discussed earlier,
and because of the common effect of
triazlne pesticides and degradates,
Office of Ground Water and Drinking
Water (OGWDW) and OPP are
coordinating to have atrazine and
slmazine, and possibly other triazines, if
warranted, addressed as a group. A
triazine special review was initiated by
OPP which will culminate in a
proposed decision on the labeling and
agricultural use triazine. The proposal is
expected during the summer of 1998.
The triazines are also included in the
Priority Group 1 of pesticide tolerances
that will be examined first under the
FQPA tolerance reassessment (62 FR
42020). •
The Agency is concerned about
triazines in water and die exposure of
sensitive populations, including
children, and OGWDW will work
closely with OPP to characterize the risk
of triazines in food and water. EPA has
been studying the mechanism of
carcinogenicity of this group of
analogues along with their degradation
products, and will continue to study
these chemicals as a group to
characterize their risk in drinking water.
The Agency may ultimately develop
regulations for the mixtures of triazines
either through the revision of existing
regulations or the development of new
ones. The same may occur for other
families of pesticides, such as the
acetanilide pesticides, which include
acetochlor, metolachor, alachlor (which
is currently regulated), given their
common effects and agricultural uses.
I. Contaminants for Which Unregulated
Contaminant Data Are or Will Be
Available
Unregulated contaminant monitoring
data which have been collected a
number of contaminants during 1988-
1991, and additional monitoring data
collected during 1993-1995 (see Table
7). These monitoring data can serve in
evaluating whether these contaminants
should be included on the CCL. The
data collected during 1988-1991 have
been preliminarily evaluated by the
Agency; however, further analysis is
necessary to determine if a contaminant
in fact meets the criteria used to develop
the draft CCL. The data collected during
1993-1995, are not yet available;
however, during the comment period,
and prior to publishing the CCL by
February 1998, the Agency will attempt
to obtain and evaluate this data to
determine if the contaminant should
remain on the CCL. Contaminants that
do not meet the criteria as presented in
today's notice, or as modified
subsequent to the comment period of
the notice, will not be included on the
final CCL to be published by February
1998.
Table 7. Contaminants with Unregulated
Contaminant Monitoring Data
1,3-dichloro-benzene
1,2,4-trimethyl-benzene
1,3-dichloropropene
1,3-dichloro-propane
1,1,2,2-tetrachloro-ethane
1.1-di-chloro-ethane
1,1-dichloro-propene
1,2,3-trichloro-propane
2,2-dichloro-propane
bromobenzene
bromomethane
carbaryl
o-chorotoluene
p-chlorotoluene
cumene
cymene
dichloro-difluoromethane
hexachlorobutadiene
metolachlor
metribuzan
naphthalene
n-propylbenzene
trichlorofluoro-methane
V. Request for Comment
The purpose of today's notice is to
present the draft CCL and seek comment
on various aspects of its development.
The Agency requests comment on the
approach used to develop the CCL, and
on the contaminants included. The
Agency also requests comment on the
data and research needs categories the
contaminants have been divided into, in
Table 8. Any data supporting comments
or that can be used by the Agency in
developing the final CCL are also
requested. In addition to comments on
contaminants considered for the draft
CCL, the Agency, seeks comment on the
inclusion of perchlorate on the final
CCL. The following sections provide
more detail on the data and research
needs and the issue of perchlorate.
A. Data and Research Needs
The microbiological contaminants
included on the CCL all have research
needs of one sort or another in the area
of analytical methods. The meeting
summary of the Workshop on
Microbiology and Public Health, held
May 20-21,1997, provided more detail
of the research needed for
microorganisms.
For the chemical contaminants on the
draft CCL, Table 8 divides them into
categories to represent the data needs
for each contaminant. Sufficient data are
needed to conduct analyses on extent of
exposure and risk to populations via
drinking water in order to determine
appropriate Agency action
(development of health advisories, or
regulations, or no action) for a given
contaminant. If sufficient data are not
available, they must be obtained before
such an assessment can be made. The
data and information required will be
gathered by research or monitoring
programs, and are not likely to be
available for analyses to be completed
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52213
prior to 2001. Thus, the contaminants
for which sufficient data exists at the
time of publishing the CCL, are likely to
the those from which the
determinations will be made by 2001.
TABLE 8.—DATA NEEDS FOR CHEMICAL CONTAMINANTS INCLUDED ON THE DRAFT CCL
Sufficient health effects and occur-
rence data exist
Need additional health ef-
fects data, but not occur-
rence data
Need additional occurrence data,
but not health effects data
Need both health effects and occur-
rence data
1,1,2,2-tetrachloroethane; 79-34-5
1,2,4-trimethylbenzene; 95-63-6 .....
1,1-dichloro-ethane; 75-34-3
1,1-dichloro-propene; 563-58-6
1,3-dichloropropane; 142-28-9
1,3-Dichloropropene; 542-75-6
Boron; 7440-42-8
Bromobenzene; 108-86-1
Cyanazine; 21725-46-2
atrazine-desethyl (a triazine deg-
radation product); 6190-65-4.
p-Cymene; 99-87-6
Hexachloro-butadiene; 87-68-3
cumene; 98-82-8
Manganese; 7439-96-5
Methyl bromide; 74-83-9
Metolachlor; 51218-15-2
Metribuzin; 21087-64-9
Naphthalene; 91-20-3
Sodium; 7440-23-5
Zinc; 7440-66-6
Aluminum; 7429-90-5
Vanadium; 7440-62-2
1,2-diphenylhydrazine; 122-66-7
2,4,6-trichlorophenol; 88-06-2
2,2-dichloro-propane; 594-20-7 ..
2,4-dichlorophenol; 120-83-2
2,4-dinitrophenol; 51-28-5 ...
2,4-dinitrotoluene; 121-14-2
2,6-dinitrotoluene; 606-20-2
2-methyl-phenol; 95-48-7
Acetochlor; 34256-82-1
Acetone 67-64-1
Alachlor ESA (an alachlor degrada-
tion product).
Aldrin; 309-00-2
DDE; 72-55-9
Diazinon; 333-41-5
Dieidrin; 60-57-1
Dimethoate; 60-51-5
Disulfotpn, 298-04-4
Diuron; 330-54-1
Fonofos; 944-22-9
Linuron; 330-55-2
MTBE; 1634-04-4.
Molinate; 2212-67-1.
Nitrobenzene; 98-95-3.
Prometon; 1610-18-0.
RDX; 121-82-4.
Rhodamine WT.
Terbacil; 5902-51-2.
Terbufos; 13071-79-9.
EPTC; 759-94-4.
2,6-di-tert-butyl-p-benzoquinone
(DTBB); 719-22-2
DCPA mono-acid degradate; 887-
54-7
DCPA di-acid degradate; 2136-79-
0
Organotins
B. Perchlorate
Additional information and comment
is sought on the inclusion of perchlorate
on the final CCL. Perchlorate is being
mentioned in this notice because EPA
received information that it had been
detected in water in the Colorado River
and in wells in California, but the
information came too late in the process
of developing the draft CCL to evaluate
it as had been done for the other
contaminants. The information the
Agency has received regarding
perchlorate's occurrence, health effects,
source of contamination and treatment
that has been included in the docket.
This information, and any other
submitted in response to comments, as
well as additional data that the Agency
may obtain, will be considered to
determine whether perchlorate should
be included on the final CCL.
VI. Development of the Final Drinking
Water Contaminant Candidate List, the
Contaminant Identification Method,
and the Contaminant Selection Process
Between now and the publication of
the final CCL, the Agency will evaluate
comments received during the comment
period for this notice and re-evaluate
the criteria used to develop the draft
CCL and revise the CCL, as appropriate.
The final CCL will be published by
February 1998.
In addition to publishing the final
CCL, the Agency will also resume work
on the CIM and the contaminant
selection process. The development of
the CIM and the selection process will
be completed in consultation with the
NDWAC Working Group on Occurrence
& Contaminant Selection. The next
meeting of the Working Group will
likely be later this fall. The CCL, CIM
and the selection process will serve as
the cornerstones of the Agency's
regulatory development process. In
addition to developing the CCL, CIM
and the selection process with the
Adminstration policy in mind, the
Agency intends to obtain resources to
improve the screening process in order
to acquire better information, improve
analytical capability, and seek
additional stakeholder involvement.
The CCL is a critical input to shaping
the future direction of the drinking
water program, and improvements will
be made with each successive cycle of
publishing the list.
VII. Summary of Other Related Activity
Required by the SDWA
After the CCL is developed and in
accordance with the SDWA, as
amended, the Agency will determine
whether or not regulation is needed for
at least five contaminants. This step of
contaminant selection is then followed
by proposal and ultimate promulgation
of regulations for those contaminants for
which a determination has been made to
regulate. Two tools provided for in the
SDWA, as amended, that relate to
development of the CCL, are the
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Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
occurrence database and unregulated
contaminant monitoring. In identifying
contaminants for inclusion on the CCL,
and selecting contaminants for
determination, die National Drinking
Water Contaminant Occurrence
Database must be considered. The
primary mechanism for obtaining the
occurrence data for the database is the
Unregulated Contaminant Monitoring
Requirements provision. Figure 2
provides a representation of the
relationship among these various
elements. The SDWA requirements for
contaminant selection, the occurrence
database and unregulated contaminant
monitoring are presented below to give
the reader a sense of what these
requirements entail and how they relate
to the CCL and to each other.
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Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
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52216
Federal Register / Vol. 62, No. 193 / October 6, 1997 / Notices
A Contaminant Selection and
Regulatoiy Determination
The SDWA, as amended in 1996.
requires EPA to make determinations of
whether or not to regulate no fewer than
five contaminants from the CCL five
years after enactment (i.e., by August
2001), and every five years thereafter
(section 1412(b)(l)); which is also three
and a half years following each CCL.
Any of the contaminants from the CCL
that the Agency decides to regulate are
subject to proposed NPDWRs within 24
months of this decision to regulate, and
final NPDWRs within 18 months of the
proposal. The SDWA also requires that
EPA give priority to selecting
contaminants for regulation that present
the greatest public health concern.
including vulnerable populations such
as infants, the elderly, and those with
serious illness. Three criteria must be
considered when deciding whether or
not to regulate a contaminant: (1) Could
the contaminant adversely affect public
health, (2) is it known or substantially
likely to occur in public water systems
with a frequency and at levels posing a
threat to public health, and (3) will
regulation of the contaminant present a
meaningful opportunity for health risk
reduction.
The Agency will be developing a
contaminant selection process that will
address the criteria mentioned above in
concert with the contaminant
identification method. The contaminant
selection process will be used to select
contaminants from the CCL for which
determinations wiU be made, while the
CIM will be used to develop the CCL.
A conceptual approach for the CIM was
presented on December 2-3,1996, at an
EPA sponsored stakeholders meeting
(U.S. EPA, 1996b) However, in order to
meet the February 1998 deadline for
finalizing the CCL. further work on the
CIM was delayed in favor of developing
the draft CCL presented in today's
notice. The Agency, in collaboration
with the NDWAC Working Group on
Occurrence & Contaminant Selection,
will resume work on the CIM and the
contaminant selection process during
the fall of 1997. Knowledge gained
during the development of this draft
CCL, as well as the feedback received
since the December 1996 stakeholders
meeting, will be factored into the
development.
B. The National Contaminant
Occurrence Database
The SDWA, as amended in 1996.
requires EPA to establish a national
drinking water contaminant occurrence
database (NCOD) to be assembled by
August 1999 [section 1445(g)J. The
database is to include the occurrence of
both regulated and unregulated
contaminants, and, once established, is
to be used to support the
Administrator's determinations for
future regulations. The requirements for
developing the CCL also include
consulting the occurrence database.
Since the database is currently under'
development, and will not be available
for the development of this first CCL,
the Agency consulted other sources of
occurrence data. Once available,
however, the NCOD will be used not
only to develop future CCLs and
support future determinations of the
need for regulations, but to develop
future regulations.
A Stakeholder meeting was held on
May 21-22,1997, in Washington, D.C.,
on the NCOD to discuss and obtain
input from the public, states, and the
scientific community on database
design and structure, input parameters
and requirements, and the uses and
interpretation of the data. This meeting
was the first of several expected to take
place in the near future regarding the
NCOD development.
C. Unregulated Contaminant Monitoring
Regulation
The SDWA, as amended, requires
EPA to list and develop regulations for
monitoring of certain unregulated
contaminants by August 1999, and
every 5 years thereafter (section
1445(a)(2)). This provision was first
introduced with the 1986 amendments
to the SDWA and has been substantially
modified by the 1996 amendments. The
SDWA requires that the list of
unregulated contaminants not exceed
30, and that the monitoring data be
collected and maintained in the NCOD.
Criteria for determining which
contaminants on the CCL will be chosen
for the unregulated contaminant
monitoring list will be developed as part
of this regulation.
Contaminants on the CCL that need
additional occurrence data will be used
as the principal source of contaminants
for the list of unregulated contaminants.
The unregulated contaminant
monitoring provision of the SDWA will
be used as a tool to gather the
contaminant occurrence data necessary
for determining the need for drinking
water regulations.
VIII. Summary of Concurrent
Regulatory Activity Required by the
SDWA
In addition to the requirements for the
CCL and contaminant selection, the
SDWA, as amended 1996, also contain
specific provisions with regard to radon,
arsenic, sulfate, and disinfectants and
disinfection byproducts. The SDWA, as
amended, did not specify a new time
frame for finalizing rulemaking for other
radionuclides, however, EPA and the
Bull Run Coalition have entered into a
consent decree with the court
establishing timetables to finalize this
rulemaking. Regulatory activity for
radon, other radionuclides, arsenic,
sulfate, and disinfectants and
disinfection byproducts are not affected
by today's notice, but are summarized
below to provide the reader with an
update on the status these specific
activities.
A. Radon
The SDWA, as amended in 1996,
contains specific provisions for
regulating radon in drinking water
(section 1412(b) (13)). First, EPA is
required to withdraw the proposed rule
for radon which was published in 1991
and to re-propose a drinking water
regulation for radon by August 6, 1999,
and issue final regulations by August 6,
2000. The SDWA, as amended, also
requires EPA to: (1) Arrange for the NAS
to prepare a peer reviewed risk
assessment for radon that evaluates the
health effects of radon in drinking water
under conditions likely to be
experienced through residential
exposure and to assess the risk
reduction benefits from various
mitigation measures to reduce radon
levels in indoor air; (2) make available
for public comment a health risk
reduction and cost analysis comparing
costs and benefits of various possible
MCL in advance of proposing a radon
regulation; and (3) establish an
alternative-MCL. if the MCL is set at a
level that is more stringent than
necessary to reduce the contribution of
radon in indoor air originating from
drinking water to a level equal to the
national average concentration of radon
in outdoor air. States will have the
option to comply with the less stringent
alternative-MCL if they implement a
multi-media radon risk reduction
program that accomplishes greater
health protection than would be
achieved by complying with the more
stringent MCL alone.
A notice was published in the Federal
Register on August 6,1997, to withdraw
the radon proposed rule. (62 FR 42221)
The NAS risk assessment is scheduled
to be complete by July 1998, and the
HRRCA is due by February 1998. In
addition, EPA held stakeholder
meetings on June 26,1997. in
Washington, D.C., and on September 2,
1997, in San Francisco, and has
scheduled an additional stakeholder
meeting in Boston later this fall to
obtain input from the public.
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52217
B. Other Radionuclides
On July 18, 1991. EPA proposed
NPDWRs for radionuclides in public
water supplies (56 FR 33050). EPA
proposed MCLs for Radium-228 at 20
pCi/1, Radium-226 at 20 pCi/1. Uranium
at 30 pOi/1 (20 jig/1), adjusted gross
alpha at 15 pCi/1 (excluding Ra-226, U;
and Rn-222), and beta and photon
emitters (excluding Ra-228) at 4 mrem
ede/yr; MCLGs were proposed at zero.
Comments on the proposed rule were
received from approximately 600
individuals and organizations. Due to
concerns by commenters and Congress
over the most effective way to regulate
radon and other radionuclides together,
the proposed rule was put on hold,
pending passage of amendments to the
SDWA, so that EPA could gain further
clarification of Congress' intent.
The SDWA, as amended in 1996, did
not specify a new time frame for
finalizing rulemaking for radionuclides,
as it did for radon. However, an existing
consent decree providing deadlines for
regulating radionuclides was amended
in 1996 to provide that EPA would, by
November 2000, finalize a rule for
Uranium; and finalize a rule for Ra-226,
Ra-228, alpha and beta/photon emitters,
or publish its reasons for not taking final
action as to these contaminants. An
Agency Workgroup has been formed
and is process of evaluating all current
data and information, which will lead to
finalizing elements of the proposed rule
or to re-proposing NPDWRs for
radionuclides.
C. Arsenic
In 1975, EPA established National
Interim Primary Drinking Water
Regulations (NIPDWR), setting an MCL
for Arsenic at 50 jig/1. In 1985, EPA
proposed an MCLG of 50 p.g/1,
requesting comment on alternate
MCLGs of 100 p.g/1 and 0 |o,g/l. However,
the SDWA, as amended in 1986,
converted the interim standard into a
NPDWR, subject to revision by 1989.
When the Agency failed to meet the
statutory deadline for promulgating an
arsenic regulation, a citizen's group
filed suit to compel EPA to do so. EPA
entered into a consent decree to, in part,
issue the arsenic regulation. The
consent decree was amended several
times to extend the deadlines and with
passage of the 1996 Amendments was
dismissed as'to arsenic.
The SDWA, as amended, requires
EPA to conduct additional research on
arsenic in order to reduce the
uncertainty in assessing the health
effects of low exposure levels; to
propose a NPDWR for arsenic by
January 1, 2000; and to issue a final
regulation by January 1, 2001. (Sec.
1412(b)(12)) EPA developed a research
plan, made it available for public
comment, and had it peer reviewed in
January 1997. The revised research plan
will be available this fall. In addition,
EPA issued a joint request for research
proposals with the American Water
Works Association Research Foundation
(AWWARF) and the Association of
California Water Agencies (ACWA).
EPA, AWWARF and ACWA awarded
almost $3 million in grants and
contracts this summer, for up to three
years. This spring, EPA also funded an
Interagency Agreement, with the
National Research Council (NRC) of the
NAS to review EPA's risk assessment,
determine the adequacy of EPA's
current MCL for protecting human
health and surface water quality criteria,
and identify priorities for research to fill
data gaps. The NRC report will be
submitted to EPA in mid-to-late 1998. In
May, 1997, EPA convened an expert
panel to evaluate the scientific literature
on the genetic and carcinogenic effects
of arsenic in order to comment on
arsenic's mode of action and the data
supporting models extrapolating to low
dose arsenic exposures. The final report
is now being considered by EPA's IRIS
Update Group.
D. Sulfate
A December 20, 1994 proposed sulfate
regulation contained both MCLG and
MCL levels for sulfate of 500 mg/1 and
included 4 alternative compliance
options designed to allow flexible
implementation. Thereafter, the
Agency's drinking water redirection
effort concluded that sulfate was a
relatively low risk contaminant, and
further regulatory activity was
suspended. The SDWA, as amended,
requires completion of a study to
resolve risk questions and requires the
Agency to make a determination within
5 years of enactment of the
Amendments, by August 6, 2001, of
whether or not to regulate sulfate. Any
of the contaminants from the CCL that
the Agency decides to regulate are
subject to proposed NPDWRs within 24
months of this decision to regulate, and
final NPDWRs within 18 months of the
proposal. In 1997 the Agency entered
into an Interagency Agreement with the
Center for Disease Control and
Prevention (CDC). EPA and CDC are
currently waiting for completion of the
peer review of the jointly planned
health risk study for sulfate. The study
results, due in February 1999, will serve
as input for EPA's contaminant
identification and selection protocol to
decide whether or not to regulate
sulfate, and will be publicly available.
In addition, prior to deciding on the
need to regulate sulfate, the Agency
would need to make a determination on
the adequacy of existing occurrence data
for sulfate and, if inadequate, consider
approaches for filling data gaps.
E. Disinfectants and Disinfection
Byproducts
Microorganisms identified for the CCL
are not specifically targeted by the
following regulations, however they
may be indirectly controlled. Any
microorganism identified for the CCL .
which is determined later to be
adequately, although indirectly,
controlled by the following regulations,
will be subsequently withdrawn from
the CCL.
Under the Surface Water Treatment
Rule (SWTR) promulgated on June 29,
1989, (54 FR 27486), EPA set MCLGs of
zero for Giardia lamblia, viruses and
Legionella; and promulgated NPDWRs
for all public water systems (PWSs)
using surface water sources or
groundwater sources under the.direct
influence of surface water. The SWTR
includes treatment technique
requirements for filtered and unfiltered
systems that are intended to protect
against the adverse health effects of
exposure to Giardia lamblia, viruses,
and Legionella, as well as many other
pathogenic organisms.
In 1992, EPA initiated a negotiated
rulemaking to develop disinfectant and
disinfection byproducts regulations. The
Regulatory Negotiating Committee met
from November 1992 through June 1993
and included representatives of State
and local health and regulatory
agencies, public water systems, elected
officials, consumer groups and
environmental groups. "One of the major
goals addressed by die Committee was
to develop an approach that would
reduce the level of exposure from
disinfectants and disinfection
byproducts without undermining the
control of microbiological pathogens. To
accomplish this, the Committee agreed
to the development of three sets of
regulations: a two-staged Disinfectant/
Disinfection Byproducts Rule (D/DBP),
an Enhanced Surface Water Treatment
Rule (ESWTR), and an Information
Collection Rule (ICR). The purpose of
the ICR is to collect occurrence and
treatment information to evaluate the
need for possible changes to the current
SWTR, existing microbial treatment
practices, and also evaluate the need for
future regulation for disinfectants and
disinfection byproducts.
EPA would first develop an Interim-
ESWTR (IESWTR) that would only
apply to systems serving 10,000 people
or more, the committee agreed that a
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Federal Register / Vol. 62, No. 193 / October 6, 1997 /Notices
Zong-Tenm-ESWTR (LTESWTR) may be
needed for systems serving fewer than
10.000 people when the results of more
research and water quality monitoring
became available. The LTESWTR could
include additional refinements for larger
systems.
The ICR was proposed on February
10, 1994 (59 FR 6332) and promulgated
on May 14, 1996 (61 FR 24354). The D/
DBF regulations and the IESWTR were
proposed on July 29, 1994 (59 FR 38668,
59 FR 38832). The SDWA. as amended,
requires EPA to promulgate an IESWTR
and a Stage I D/DBP Rule by November
1998. In addition, the SDWA requires
EPA to promulgate a final ESWTR and
a Stage II D/DBP rule by November 2000
and May 2002, respectively [section
In light of new information that has
become available in several key areas
related to Issues put forth in the D/DBP
Stage 1 proposal, the Agency initiated a
series of public meetings in May 1996.
These meetings were designed to
exchange information on issues related
to the development of the IESWTR and
the Stage 1 D/DBP rule and the impact
of the ICR data not being available. In
order to facilitate moving in an
expedited fashion to meet the deadlines
in the 1996 Amendments, and to
maximize stakeholder participation, the
Agency subsequently established an
advisory committee to collect, share,
and analyze new information and data
as well as to build consensus on the
regulatory implications of this new
information. After evaluation of the new
data and information, the committee
made recommendations on a number of
major issues. These recommendations
and a discussion of the pertinent issues
will be published in a Federal Register
Notice planned for later this fall.
DC Other Requirements
The CCL is a notice and not a
regulatory action; therefore, the
following statutes and executive orders
are not applicable at this time: the
Regulatory Flexibility Act, Small
Business Regulatory Enforcement
Fairness Act, Paperwork Reduction Act,
Unfunded Mandates Reform Act; and
Executive Order 12866. As
contaminants are selected for
rulemaklng, all necessary analysis will
be conducted in accordance with the
rulemaklng process.
Executive Order 13045. Protection of
Children from Environmental Health
Risks and Safety Risks, requires that
Federal Agencies identify and assess
health risks and safety risks that
disproportionately affect children, and
ensure that its policies, programs,
activities, and standards address
disproportionate health and safety risks
to children.The SDWA also requires the
Agency to select priorities for regulation
while considering risk to sensitive
subpopulations, such as infants and
children. - ' • •
The impact on sensitive populations
will be addressed in the contaminant
selection process, and will be a
component of the Agency's
determination of whether or not to
regulate a given contaminant. In
preparation for addressing the issues of
sensitive subpopulations, the Agency is
sponsoring several activities to
determine water intake by age group, by
demographic distribution, and by innate
or developed sensitivity to potential
drinking water contaminants. The
Agency is also collaborating with CDC
on a study of six major cities to
determine the most sensitive
populations for drinking water
manifested during major outbreaks of
illness from incidents of water
contamination. Other research also is
underway to determine the extent of
vulnerable populations including
children and the immunologically
impaired.
X. References
ATSDR, 1996. "1995 CERCLA Priority List
of Hazardous Substances That will be The
Subject of Toxicologlcal Profiles and Support
Documents." Division of Toxicology, Agency
for Toxic Substances and Disease Registry
(ATSDR), Department of Health and Human
Services, Atlanta, GA. April.
Barber, Lany and Denis LeBlanc. 1988.
Long-Term Fate of Organic Micropollutants
in Sewage-Contaminated Groundwater.
Environ. Sci. Technol., 22:205-211.
Benenson, M., E.T. Takafuji, S.M. Lemon,
R.L. Greenup, and A.J. Sulzer. 1982. Oocyst-
transmitted toxoplasmosis associated with
ingestion of contaminated water. New Engl.
J. Med., 307:666-669.
Berman, D.. andJ.C. Hoff. 1984.
Inactivation of simian rotavirus SA11 by
chlorine, chlorine dioxice, and
monochloramine. Appl. Environ. Microbiol.,
48:317-323.
Biyan, R.T. 1995. Microsporidiosis as an
AIDS-related opportunistic infection. Clin.
Infect. Dis.. 21(Suppl l):62-65.
Call. A. 1991. General Microsporidium
Features and Recent Findings on AIDS
Isolates. J. Protozool., 38:625-630.
Chen. Y., andJ.M. Vaughn. 1990.
Inactivation of human and simian rotaviruses
by chlorine dioxide. Appl. Environ.
Microbiol., 56:1363-1366.
Cover. T.L.. and M.J. Blaser. 1995.
Helicobacter pylori: A Bacterial Cause of
Gastritis, Peptic Ulcer Disease, and Gastric
Cancer. ASM News, 61:21-26.
Cubitt, W.D. 1991. A Review of the
Epidemiology and Diagnosis of Waterborne
Viral Infections. Water Science and Tehnol.,
24:197-203.
de Jonckheere, J., and H. van de Voorde.
1976. Differences in Destruction of Cysts of
Pathogenic and Nonpathogenic Naegleria and
Acanthamoeba by chlorine. Appl. Environ.
Microbiol., 31:294-297.
Dreesman, G.R., and G.R. Reyes. 1992.,
Hepatitus. In Encyclopedia of Microbiology,
Vol. 2, Edited by J. Lederberg. pp. 371-380.
Sari Diego: Academic Press.
Du Moulin, G.C. and K.D. Stottmeier. 1986.
Waterborne Mycobacteria: An Increasing
Threat to Health. ASM News, 52:525^529.
Du Moulin. G.C.. K.D. Stottmeier, P.A.
Pelletier, A.Y. Tsang. and J. Hedley-Whyte.
1988. Concentration of Mycobacterium
avium by Hospital Hot Water Systems. J.
Amer. Med. Assoc., 260:1599-1601.
Fishback, J.L. 1992. Toxoplasmosis.'In
Encyclopedia of Microbiology, Vol. 2, Edited
by J. Lederberg. pp. 255-264. San Diego:
Academic Press.
Gerba, C.P.. J.B. Rose. CN Has, and K.D.
Crabtree. 1996. Waterborne rotavirus: a risk
assessment. Water Res.. 30(12):2929-2940.
Gerba, C.P.. J.B. Rose, S.N. Singh. 1985.
Waterborne gastroenteritis and viral
hepatitis. CRC Critical Reviews in
Environmental Control, 15(3):213-236.
Gonzalez-de-la-Cuesta, N., M. Arias-
Femandez, E. Paniagua-Crespo, and M.
Marti-Mallen. 1987. Free-living Amoebae in
Swimming Pool Waters from Galicia (Spain).
Rev. Iber. Parasitol.. 47:207-210. Abstract in
English only; text in Spanish.
Goodgame, R.W. 1996. Understanding
Intestinal Spore-forming Protozoa:
Cryptosporidia, Microsporidia, Isospora, and
Cyclospora. Ann. Intern. Med., 1214:429-
441.
Grohmann, G.S. et al. 1993. Enteric Viruses
and Diarrhea in HIV-Infected Patients. New
EngLJ. Med., 329:14-20.
Hardalo, C.. and S.C. Edberg. 1997.
Pseudomonas aeruginosa: Assessment of Risk
from Drinking Water. Crit. Rev. Microbiol.
23(l):47-75.
Huang, P., J.T. Weber, D.M. Sosin. E.G.
Long. JJ. Murphy, F.Kocka. C. Peters, and C.
Kallick. 1995. The First Reported Outbreak of
Diarrheal Illness Associated with Cyclospora
in the United States. Ann. Internal Med., 123:
409-414.
Hulten. K. et al. 1996. Helicobacter pylori
in the Drinking Water in Peru.
Gastroenterology, 110:1031-1035.
Hurst, CJ. 1991. Presence of enteric viruses
in freshwater and their removal by the
conventional drinking water treatment
process. Bulletin of the World Health
Organization, 69(1):113-119.
Interagency Assessment of Oxygenated
Fuels (IAOF). 1997. Prepared by National
Science and Technology Council and
Committee on Environment and Natural
Resources.
Kilvington, S. 1990. Activity of Water
Biocide Chemicals and Contact Lens'
Disinfectants on Pathogenic Free-living
Amoebae. Intl. Biodeterior.. 26:127-138.
Klein, P.O., D.Y. Graham, A., Gaillour, A.R.
Opekun, and E.O. Smith. 1991. Water source
as risk factor for Helicobacter pylori infection
in Peruvian children. Lancet, 337:1503-1506.
Kramer, M.H., B.L. Herwaldt, G.F. Craun,
R.L.Calderon. and D.D. Juranek. 1996.
Surveillance for Waterbome-Disease
Outbreaks—United States, 1993-1994. CDC
Surveillance Summaries, Morbidity and
-------
Federal Register / Vol: 62, No. 193 / October 6, 1997 / Notices
52219
Mortality Weekly Report, 45(SS-l):l-33
(April 12, 1996). Centers for Disease Control.
Kurtz, J.B., and T.W. Lee. 1987.
Astroviruses: Human and Animal. In Novel
Diarrhoea Viruses. John New York: Wiley &
Sons.
Lippy, E.G. and J. Erb. 1976.
Gastrointestinal illness at Sewickly, Pa. Jour.
American Water Works Assoc., 68:606-610.
Melnick, J.L. 1992. Enteroviruses. In
Encyclopedia of Microbiology, Vol. 2. pp.
69-80. Edited by J. Lederberg. Academic
Press.
Nomura, A., G.N. Stemmermann, P-H
Chyou, I. Kato, G.I. Perez-Perez, and MJ.
Blaser. 1991. Helicobacter pylori Infection
and Gastric Carcinoma Among Japanese
Americans in Hawaii. New Engl. J. Med,,
325:1132-1136.
Parsonnet, J. 1992. Gastrointestinal
microbiology. In Encyclopedia of
Microbiology. Vol. 2. Edited byj. Lederberg.
Academic Press. New York. Pgs. 245-258.
Parsonnet, J., G.D. Friedman, D.P.
Vandersteen, Y. Chang, J.H. Vogelman, N.
Orentreich. and R.K. Sibley. 1991.
Helicobacter pylori Infection and the Risk of
Gastric Carcinoma. N. Eng. J. Med.,
325:1127-1131.
Pelletier. PA, GC du Moulin, and KD
Stottmeier. 1988. Mycobacteria in public
water supplies: comparative resistence to
chlorine. Microbiol Sciences. 5:147-148.
Peterson. D.A.. T.R. Hurley, j.C. Hoff, and
L.G. Wolfe. 1983. Effect of chlorine treatment
on infectivity of hepatitis A virus. Appl.
Environ. Microbiol., 45:223-227.
Peterson, W.L. 1991. Helicobacter pylori
and Peptic Ulcer Disease. N. Eng. J. Med..
324:1043-1048.
Pinto. RM, FX Abad, R. Gajaardo, and A.
Bosch. 1996. Detection of infectious
astroviruses in water. Appl. Environ.
Microbiol., 62:1811-1813.
Sadiki, Abdel-Hah, David Williams,
Richard Carrier, and Barry Thomas. 1996.
Pilot Study of the Contamination of Drinking
Water by organotin Compounds from PVC
Materials. Chemosphere, 32:2389-2398.
Sawyer, T.K. 1989. Free-living Pathogenic
and Nonpathogenic Amoebae in Maryland
Soils. Appl. Environ. Microbiol., 55:1074-
1077.
Seal. D.. F. Stapleton, andj. Dart. 1992.
Possible Environmental Sources of
Acanthamoeba spp. in Contact Lens Wearers.
Br. J. Ophthalmology, 76:424-427.
Shahamat M.^ R.R. Colwell, and C. Paszko-
Kolva. 1992. Letter to Editor. Jour. AWWA.
84(10):4. .
Shahamat M., U. Mai, C. Paszko-Kolva, and
R.R. Colwell. 1993. Use of Autoradiography
to Assess Viability of Helicobacter pylori in
Water. Appl. Environ. Microbiol., 59:1231-
1235.
Soave, R. and W.D. Johnson, Jr. 1995.
Cyclospora: Conquest of an Emerging
Pathogen (comment). Lancet, 345: 667-668.
States. S.J., R.M. Wadowsky, J.M. Kuchta,
R.S. Wolford, L.F. Conley, and R.B. Yee.
1990. Legionella in Drinking.Water. In:
Drinking Water Microbiology. G.A. McFeters
(ed). pp 340-367. Springer-Verlag, New York.
Sutton, L.D., W.W. Wilke, N.A. Lynch, and
R.N. Jones. Helicobacter Pylori Containing
Sewage Detected By the Polymerase Chain
Reaction. ASM Annual Meeting, 1995.
Abstract C-395.
Thomas, D.L., P.O.Yarbough, D. Vlahov,
S.A. Tsarev, K.E. Nelson, A.J. Saah, and R.H.
Purcell. 1997. Seroreactivity to hepatitis E
virus in areas where the disease is not
endemic. J. Clin. Microbiol, 35:1244-1247.
U.S. EPA. 1987. "Notice of the First
Priority List of Hazardous Substances That
will be the Subject of Toxicological Profiles."
52 FR 12866, April 17.
U.S. EPA. 1988. "Drinking Water;
Substitution of Contaminants and Drinking
Water Priority List of Additional Substances
Which may Require Regulation Under the
Safe Drinking Water Act." 53 FR 1892,
January 22.
U.S. EPA. 1989a. "Drinking Water;
National Primary Drinking Water
Regulations; Filtration. Disinfection;
Turbidity, Glardia lamblia, Viruses.
Legionella, and Heterotrophic Bacteria; Final
Rule (Surface Water Treatment Rule)." 54 FR
27486-27541. June 29.
U.S. EPA. 1989b. "Control of Legionella in
Plumbing Systems," In: Reviews of
Environmental Contamination and
Toxicology, vol. 107 pp. 79-92 (G.W. Ware,
ed.). Springer-Verlag, New York.
U.S. EPA. 1990. "National Primary
Drinking Water Regulations; Synthetic
Organic Chemicals and Inorganic
Chemicals." Proposed Rule; 55 FR 30370-
30448—Part H. July 25.
U.S. EPA. 1991a." Priority List of
Substances Which May Require Regulation
Under the Safe Drinking Water Act; Notice."
56 FR 1470. January 14.
U.S. EPA. I991b. "National Primary .
. Drinking Water Regulations; Monitoring for
VOC; MCLGs and MCLs for Aldicarb,
Aldicarb Sulfoxide, Aldicarb Sulfone,
Pentachlorophenol, and Barium." 56 FR
30266-30281, July 1.
EPA. 1991c. "Notice of Proposed
Rulemaking: National Primary Drinking
Water Regulations; Radionuclides," 56 FR
33050. July 18.
U.S. EPA. 1992. "National Primary and
Secondary Drinking Water Regulations;
Synthetic Organic Chemicals and Inorganic
Chemicals." 57 FR 31776-31849—Part ffl.
July 17.
U.S. EPA. 1995. "National Pollutant
Discharge Elimination System and
Pretreatment Programs; State and Local
Assistance Programs; Effluent Limitations
Guidelines and Standards; Public Water
Supply and Underground Injection Control
Programs: Removal of Legally Obsolete or
Redundant Rules." 60 FR 33926-33972, June
29.
U.S. EPA. 1996a. "Drinking Water Program
Redirection Strategy," Office of Water. EPA
810-R-96-003,June.
U.S. EPA. 1996b. "The Conceptual
Approach for Contaminant Identification
(working draft). EPA 812-D-96-001.
November.
U.S. EPA. 1997a. "Special Report on
Environmental Endocrine Disruption: On
Effects Assessment and Analysis, EPA 630-
R-96-012, February.
U.S. EPA. 1997b. "EFED Selection of
Pesticide Candidates for MCL and HAL
Development," Internal Memorandum with
attachments from Michael Barrett and Estella
Waldman, Office of Pesticide Programs to
Amal Mahfouz, Office of Water, March 27.
U.S. EPA. 1997c. "1995 Toxics Release
Inventory," EPA 745-R-97-005, April.
U.S. EPA. 1997d. "Raw and Processed
Food Schedule for Pesticide Tolerance
Reassessment." 62 FR 42020-42027, August
4.
U.S. EPA. 1997e. "Research Strategy for
Oxygenates in Water," Workshop Review
Draft. Office of Research and Development,
September 5.
U.S. EPA. 1997f. "Water Quality Criteria;
Ambient Water Quality Criteria," 62 FR No.
152 42554. August 7.
Vaughn, J.M., Y. Chen. K. Lindburg, and D.
Morales. 1987. Inactivation of human and
simian rotaviruses by ozone. Appl. Environ.
Microbiol., 53:2218-2221
Vaughn, J.M., Y. Chen, and M.ZJ Thomas. -
1986. Inactivation of human and simian
rotaviruses by chlorine. Appl. Environ.
Microbiol.. 51:391-394.
Waller, T. 1979. Sensitivity of
Encephalitozoon cuniculi to Various
Temperatures, disinfectants and drugs. Lab.
Anim., 13:227-230.
Weber. R.. R. Bryan, D. Schwartz, and R.
Owen 1994. Human Microsporidial
Infections. Clin. Microbiol. Rev.. 7:426-461.
Yu. V.L., J.J. Zuravleff, L. Gavlik, M.H.
Magnussen. 1983. Lack of Evidence for
Person-to-person Transmission of
Legionnaires' Disease. J. Infect. Dis., 147:362.
(Authority: 42 U.S.C. 300f-300j-25)
Dated: September 29. 1997.
Robert Perciasepe,
Assistant Administrator, Office Water.
Environmental Protection Agency.
{FR Doc. 97-26433 Filed 10-3-97; 8:45 ami
BILLING CODE 6S60-K-P
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