[Federal Register Volume 66, Number 207 (Thursday, October 25, 2001)]
[Notices]
[Pages 54014-54016]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-26875]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Agency for Toxic Substances and Disease Registry

[ATSDR-176]


Notice of the Revised Priority List of Hazardous Substances That 
Will Be the Subject of Toxicological Profiles

AGENCY: Agency for Toxic Substances and Disease Registry (ATSDR), U.S. 
Department of Health and Human Services (HHS).

ACTION: Notice.

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SUMMARY: The Comprehensive Environmental Response, Compensation, and 
Liability Act (CERCLA or Superfund), as amended by the Superfund 
Amendments and Reauthorization Act (SARA), requires that ATSDR and the 
Environmental Protection Agency (EPA) revise the Priority List of 
Hazardous Substances. This list includes substances most commonly found 
at facilities on the CERCLA National Priorities List (NPL) which have 
been determined to be of greatest concern to public health at or around 
these NPL hazardous waste sites. This announcement provides notice that 
the agencies have developed and are making available a revised CERCLA 
Priority List of 275 Hazardous Substances, based on the most recent 
information available. Each substance on the priority list is a 
candidate to become the subject of a toxicological profile prepared by 
ATSDR and subsequently a candidate for the identification of priority 
data needs.
    In addition to the Priority List of Hazardous Substances, ATSDR has 
developed a Completed Exposure Pathway Site Count Report. This report 
lists the number of sites or events with ATSDR activities where a 
substance has been found in a completed exposure pathway (CEP). This 
report is included in the Support Document of the Priority List.

ADDRESSES: Requests for a copy of the report, the 2001 CERCLA Priority 
List of Hazardous Substances That Will Be The Subject of Toxicological 
Profiles and Support Document, including the CEP report, should bear 
the docket control number ATSDR-176, and should be submitted to: ATSDR 
Information Center, Division of Toxicology, Mail Stop E-29, 1600 
Clifton Rd., NE., Atlanta, GA 30333. Requests must be in writing.
    Electronic Availability: The 2001 Priority List of Hazardous 
Substances will be posted on ATSDR's World-Wide Web server on the 
Internet located at http://www.atsdr.cdc.gov.clist.html.

[[Page 54015]]

The CEP Report will also be posted at http://www.atsdr.cdc.gov.cep.html.
    This is an informational notice only, and comments are not being 
solicited at this time. However, any comments received will be 
considered for inclusion in the next revision of the list and placed in 
a publicly accessible docket; therefore, please do not submit 
confidential business or other confidential information.

FOR FURTHER INFORMATION CONTACT: ATSDR, Division of Toxicology, 
Emergency Response and Scientific Assessment Branch, 1600 Clifton Road 
N.E., Mail Stop E-29, Atlanta, GA 30333, telephone 888-422-8737.

SUPPLEMENTARY INFORMATION: CERCLA establishes certain requirements for 
ATSDR and EPA with regard to hazardous substances that are most 
commonly found at facilities on the CERCLA NPL. Section 104(i)(2) of 
CERCLA, as amended [42 U.S.C. 9604(i)(2)], required that the two 
agencies prepare a list, in order of priority, of at least 100 
hazardous substances that are most commonly found at facilities on the 
NPL and which, in their sole discretion, have been determined to pose 
the most significant potential threat to human health (see 52 FR 12866, 
April 17, 1987). CERCLA also required the agencies to revise the 
priority list to include 100 or more additional hazardous substances 
(see 53 FR 41280, October 20, 1988), and to include at least 25 
additional hazardous substances in each of the three successive years 
following the 1988 revision (see 54 FR 43619, October 26, 1989; 55 FR 
42067, October 17, 1990; 56 FR 52166, October 17, 1991). CERCLA also 
requires that ATSDR and EPA shall, at least annually thereafter, revise 
the list to include additional hazardous substances that have been 
determined to pose the most significant potential threat to human 
health. In 1995, the agencies altered the publication schedule of the 
priority list by moving to a 2-year publication schedule, reflecting 
the stability of this listing activity (60 FR 16478, March 30, 1995). 
As a result, the priority list is now on a 2-year publication schedule 
with a yearly informal review and revision. Each substance on the 
CERCLA Priority List of Hazardous Substances is a candidate to become 
the subject of a toxicological profile prepared by ATSDR and 
subsequently a candidate for the identification of priority data needs.
    The initial priority lists of hazardous substances (1987-1990) were 
based on the most comprehensive and relevant information available when 
the lists were developed. More comprehensive sources of information on 
the frequency of occurrence and the potential for human exposure to 
substances at NPL sites became available for use in the 1991 priority 
list with the development of ATSDR's HazDat database. Utilizing this 
database, a revised approach and algorithm for ranking substances was 
developed in 1991, and a notice announcing the intention of ATSDR and 
EPA to revise and rerank the Priority List of Hazardous Substances was 
published on June 27, 1991 (56 FR 29485). The subsequent 1991 Priority 
List and revised approach used for its compilation was summarized in 
the ``Revised Priority List of Hazardous Substances'' Federal Register 
notice published October 17, 1991 (56 FR 52166). The same approach and 
the same basic algorithm have been used in all subsequent activities, 
including the 2001 listing activity. The algorithm used in ranking 
hazardous substances on the priority list consists of three criteria, 
which are combined to result in the total score. The three criteria 
are: frequency of occurrence at NPL sites; toxicity; and potential for 
human exposure.
    Since HazDat is a dynamic database with ongoing data collection, 
additional information from the HazDat database became available for 
the 2001 listing activity. This additional information has been entered 
into HazDat since the development of the 1999 Priority List of 
Hazardous Substances. The site-specific information from HazDat that is 
used in the listing activity has been collected from ATSDR public 
health assessments, health consultations, and from site file data 
packages that are used to develop these public health assessments. The 
new information may include more recent NPL frequency of occurrence 
data, additional concentration data, and more information on exposure 
to substances at NPL sites. With these additional data and with a 
refinement made in assigning toxicity scores to radionuclides for this 
listing purpose, 18 substances have been replaced on the list of 275 
substances since the 1999 publication. Of the 18 replacement 
substances, 5 are new candidate substances, and 13 are substances that 
were previously under consideration. These replacement substances and 
changes in the order of substances appearing on the CERCLA Priority 
List of Hazardous Substances will be reflected in the program 
activities that rely on the list for future direction.
    The 2001 Priority List of Hazardous Substances includes 275 
substances that have been determined to be of greatest concern to 
public health based on the criteria of CERCLA section 104(i)(2) [42 
U.S.C. 9604(i)(2)]. A total of 840 candidate substances have been 
analyzed and ranked with the current algorithm. Of these candidates, 
the 275 substances on the priority list may become the subject of 
toxicological profiles in the future. The top 25 substances on the 2001 
Priority List of Hazardous Substances are listed below.

------------------------------------------------------------------------
              Rank                            Substance name
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1...............................  Arsenic
2...............................  Lead
3...............................  Mercury
4...............................  Vinyl Chloride
5...............................  Polychlorinated Biphenyls
6...............................  Benzene
7...............................  Cadmium
8...............................  Benzo (A) Pyrene
9...............................  Polycyclic Aromatic HYDROCARBONS
10..............................  Benzo (B) Fluoranthene
11..............................   Chloroform
12..............................  DDT, P,P'-
13..............................  Aroclor 1254
14..............................  Aroclor 1260
15..............................  Trichloroethylene
16..............................  Dibenzo (A,H) Anthracene
17..............................  Dieldrin
18..............................  Chromium, Hexavalent
19..............................  Chlordane
20..............................  Hexachlorobutadiene
21..............................  DDE, P,P'-
22..............................  Coal Tar Creosote
23..............................  Aldrin
24..............................  Phosphorus, White
25..............................  Benzidine
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    ATSDR and EPA intend to publish the next revised list of hazardous 
substances in two years, with an informal review and revision performed 
in one year. These revisions will reflect changes and improvements in 
data collection and availability. Additional information on the 
existing methodology used in the development of the CERCLA Priority 
List of Hazardous Substances can be found in the Support Document to 
the List and in the Federal Register notices mentioned above.
    In addition to the revised priority list, ATSDR is also releasing a 
Completed Exposure Pathway Site Count Report. A completed exposure 
pathway (CEP) is an exposure pathway that links a contaminant source to 
a receptor population. The CEP ranking is very similar to a sub-
component of the potential-for-human-exposure component of the listing 
algorithm. The CEP ranking is based on a site frequency count, and thus 
lists the number of sites at which a substance has been found in a CEP. 
ATSDR's HazDat database contains this information which is derived from 
ATSDR public health assessments and health consultations.

[[Page 54016]]

Because exposure to hazardous substances is of significant concern, 
ATSDR has been tabulating the substances to which people have been 
exposed at hazardous waste sites. Much interest has been focused on 
this tabulation. Therefore, ATSDR is announcing the publishing of this 
CEP report along with the CERCLA Priority List of Hazardous Substances. 
Since this CEP report focuses on documented exposure, it provides an 
important prioritization based on substances to which people are 
exposed.
    The substances on the CEP report are similar to the substances on 
the CERCLA Priority List of Hazardous Substances. However, there are 
some substances that are on the CEP report, because they are frequently 
found in completed exposure pathways, but are not on the CERCLA 
Priority List because they have a very low toxicity (e.g., sodium). 
Since the CERCLA Priority List incorporates three different components 
(toxicity, frequency of occurrence, and potential for human exposure) 
to determine its priority substances, substances with very low toxicity 
are not on the CERCLA Priority List and consequently are not the 
subject of toxicological profiles. In addition, since the Priority List 
is mandated by CERCLA, it only uses data from sites on the CERCLA 
National Priorities List, whereas the CEP report uses data from all 
sites with ATSDR activities that have a CEP. Of the 100 substances on 
the CEP report, the 25 substances found at the most number of sites in 
a CEP are presented below.

                 Number of Sites With Substance in a CEP
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                Substance name                   All sites    NPL sites
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Lead..........................................          359          238
Trichloroethylene.............................          319          271
Arsenic.......................................          267          176
Tetrachloroethylene...........................          236          190
Cadmium.......................................          176          123
Benzene.......................................          174          128
Chromium......................................          169          113
Volatile Organic Compounds, Unspecified.......          162          118
Polychlorinated Biphenyls.....................          152          104
Mercury.......................................          136           82
Zinc..........................................          134           83
Manganese.....................................          134           80
1,1,1-Trichloroethane.........................          125          106
Copper........................................          118           67
Chloroform....................................          113           88
1,1-Dichloroethene............................          105           91
Methylene Chloride............................          103           72
Toluene.......................................          102           68
Vinyl Chloride................................           99           84
Nickel........................................           98           63
Benzo (A) Pyrene..............................           98           54
Polycyclic Aromatic Hydrocarbons..............           97           68
Barium........................................           96           54
Antimony......................................           88           57
1,2-Dichloroethane............................           86           71
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    Note: Sorted by the All Sites column. All Sites = all sites with 
ATSDR activities that have a CEP; NPL Sites = current and former 
sites on the National Priorities List, as mandated.


    Dated: October 18, 2001.
Donna Garland,
Deputy Director, Office of Policy and External Affairs, Agency for 
Toxic Substances and Disease Registry.
[FR Doc. 01-26875 Filed 10-24-01; 8:45 am]
BILLING CODE 4163-70-P