[Federal Register Volume 62, Number 221 (Monday, November 17, 1997)]
[Notices]
[Pages 61332-61335]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-30055]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Agency for Toxic Substances and Disease Registry
[ATSDR-130]


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), 
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

[[Page 61333]]

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 to ATSDR and EPA. 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 has been added to the Support Document of the Priority List.

ADDRESSES: Requests for a copy of the report, the 1997 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-130, and should be submitted to: Lydia 
Wilcox, ATSDR Information Center, Division of Toxicology, Mail Stop E-
29, 1600 Clifton Rd., N.E., Atlanta, GA 30333. Requests must be in 
writing.
    Electronic Availability: The 1997 Priority List of Hazardous 
Substances will be posted on ATSDR's World-Wide Web server on the 
Internet located at http://atsdr1.atsdr.cdc.gov:8080/atsdrhome.html. 
The priority list will also be posted on the Federal Bulletin Board on 
or near the day of publication of this notice in the Federal Register.
    To access the Federal Bulletin Board via the Internet, telnet 
fedbbs.access.gpo.gov. This file is available in WordPerfect 5.1, Dbase 
III, and ASCII formats.
    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 information.

FOR FURTHER INFORMATION CONTACT: ATSDR, Division of Toxicology, 
Emergency Response and Scientific Assessment Branch, 1600 Clifton Road 
NE, Mail Stop E-29, Atlanta, GA 30333, telephone 800-447-1544.

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)), requires 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 requires 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 algorithm have been used in all subsequent activities, 
including the 1997 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 1997 listing activity. This additional information has been entered 
into HazDat since the development of the 1995 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, 28 substances 
have been replaced on the list of 275 substances. Of the 28 replacement 
substances, 10 are new candidate substances, and 18 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. These changes 
reflect the dynamic nature of scientific data on substances present at 
NPL hazardous waste sites.
    In 1996, an extensive review of the toxicity values (Reportable 
Quantities or Toxicity/Environmental Scores) for the candidate 
substances was performed. The purpose of this review was to determine 
if any new information on the toxicity of the candidate substances had 
become available since the substances were first evaluated (most in 
1991). As a result, a number of substances had their toxicity values 
revised to reflect the new information. Lead is one of the few 
substances with a Reportable Quantity (RQ) change that was identified 
during this review (changed from RQ of 1 to RQ of 10). Since the 
toxicity component of the listing algorithm is based on the RQ, this

[[Page 61334]]

change caused Lead to drop from the number one rank on the priority 
list to the number two rank, with Arsenic replacing it at number one.
    The 1997 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 775 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 1997 
Priority List of Hazardous Substances are listed below.

------------------------------------------------------------------------
              Rank                            Substance name            
------------------------------------------------------------------------
-1..............................  Arsenic.                              
-2..............................  Lead.                                 
-3..............................  Mercury.                              
-4..............................  Vinyl chloride.                       
-5..............................  Benzene.                              
-6..............................  Polychlorinated biphenyls.            
-7..............................  Cadmium.                              
-8..............................  Benzo (a) pyrene.                     
-9..............................  Benzo (b) fluoranthene.               
10..............................  Polycyclic aromatic hydrocarbons.     
11..............................  Chloroform.                           
12..............................  Aroclor 1254.                         
13..............................  P,P'--DDT.                            
14..............................  Aroclor 1260.                         
15..............................  Trichloroethylene.                    
16..............................  Hexavalent chromium.                  
17..............................  dibenzo (a,h) anthracene.             
18..............................  Dieldrin.                             
19..............................  Hexachlorobutadiene.                  
20..............................  Chlordane.                            
21..............................  Creosote.                             
22..............................  P,P'--DDE.                            
23..............................  Benzidine.                            
24..............................  Cyanide.                              
25..............................  Aldrin.                               
------------------------------------------------------------------------

    This evaluation activity and announcement of a revised Priority 
List of Hazardous Substances fulfills the conditions of CERCLA section 
104(i), as amended. 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 previously.
    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. 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. Recently much interest has been focused on this 
tabulation. Therefore, ATSDR will henceforth publish 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. Of the 100 substances on the CEP 
report, the 25 substances found at the most number of sites in a CEP 
are presented below.

------------------------------------------------------------------------
                                                    No. of sites with   
                                                   substance in a CEP   
                Substance name                 -------------------------
                                                 All sites    NPL sites 
------------------------------------------------------------------------
TRICHLOROETHYLENE.............................          227          213
LEAD..........................................          206          181
TETRACHLOROETHYLENE...........................          171          157
ARSENIC.......................................          138          121
BENZENE.......................................          121          110
CADMIUM.......................................          102           91
CHROMIUM......................................           99           91
1,1,1-TRICHLOROETHANE.........................           95           86
POLYCHLORINATED BIPHENYLS.....................           90           79
1,1-DICHLOROETHENE............................           77           73
CHLOROFORM....................................           76           73
ZINC..........................................           76           66
MERCURY.......................................           74           61
1,1-DICHLOROETHANE............................           71           69
VINYL CHLORIDE................................           71           69
MANGANESE.....................................           70           60
1,2-DICHLOROETHANE............................           67           63
METHYLENE CHLORIDE............................           65           62
VOLATILE ORGANIC COMPOUNDS....................           61           54
TOLUENE.......................................           60           54
COPPER........................................           60           51
NICKEL........................................           53           49
CARBON TETRACHLORIDE..........................           49           42
BARIUM........................................           48           43
POLYCYCLIC AROMATIC HYDROCARBONS..............           47           44
------------------------------------------------------------------------
Note: Sorted by the All Sites column.                                   
ALL Sites = all sites with ATSDR activities; NPL sites = current and    
  former sites on the National Priorities List, as mandated.            


[[Page 61335]]

Administrative Record

    An administrative record entitled ATSDR-130 will be established for 
materials pertaining to this notice. All materials received as a result 
of this notice will be included in the public file available for 
inspection from 8 a.m. to 4:30 p.m., Monday through Friday, except 
Federal legal holidays, at the Agency for Toxic Substances and Disease 
Registry, #4 Executive Park Drive, Suite 2400, Atlanta, Georgia (not a 
mailing address).

    Dated: November 7, 1997.
Georgi Jones,
Director, Office of Policy and External Affairs, Agency for Toxic 
Substances and Disease Registry.
[FR Doc. 97-30055 Filed 11-14-97; 8:45 am]
BILLING CODE 4163-70-P