### Federal.Registerj Vol. 51, No. 96 / Monday, May 19, 1986 / Notices

iOPTS-41021; FRL-3017-21
Eighteenth Report.ofthe Interagency Testing Committee to the

. --. .- Administrator;Receipt of Report and Request forComments Regarding Priority Listof Chemicals

AGENCY:.Environmental Protection Agency (EPA). ACTION: Notice.
SUMMARY: The Interagency Testing' Committee (ITC), established under section 4(e) ofthe Toxic Substances Control Act (TSCA), transmitted its Eighteenth Report to the Administrator ofEPA on May 1, 1986.This report, which revises and updates the Committee's priority list ofchemicals, adds one chemical to the list for priority consideration by EPAin the promulgation oftest rules under section 4(a) ofthe Act, The new chemical is tributyl phosphate. This chemical isnot designated forresponse within 12 months. Two substances previously recommended with intent to designate, cyclohexane and 2,6-di-tert-butylphenol (50FR 47603), arenow designated for response within 12 months. The Eighteenth Report is included in this notice. TheAgency invites interested
persons to submit written comments on the Report, and to attend a Focus Meeting to help narrow and focus the issues raised by the ITC's recommendations. Members ofthe public are also invited to inform EPA ifthey wish to benotified ofsubsequent public meetings on these chemicals. ITC also notes the removal of6 chemicals from thepriority list because.EPA has responded to the ITC's previous

- recommendations fortesting ofthe chemicals. DATES: Written comments should be submitted by June 18, 1986.A Focus Meeting Will be held on June 17. 1986. ADDRESSES: Send written submissions
to: TSCA Public Information Office (TS793), Office ofPesticides and Toxic

. Substances, Environmental Protection Agency, Rm. E-108, 401 M St., SW., Washington, DC 20460.
Submissions should bear the document control number (OPTS-41021).

Thepublic record supporting this action, including comments, is available for public inspection inRm. E-107 at the address noted above from 8 a.m. to 4 p.m. Monday through Friday, except legal holidays. The Focus Meeting will be held at EPA Headquarters, Rm. 103. NE Mall, 401 M St., SW., Washington, DC. Persons planning to attend the -FocusMeeting and/or sdeking tobe informed.of subsequent public meetings

on this chemical, should notify the TSCA Assistance Office at the address listed below. To insure seating accommodations at the Focus Meeting,
persons,interested in attending are asked tonotify EPA.atleast one w.eek ahead of the scheduled date.

FOR FURTHER INFORMATION CONTACT: Edward A. Klein, Director, TSCA Assistance Office (T,--799), Office of Toxic Substances, Environmental Protection Agency, 401 M St., SW., Washington, DC 20460. Toll Free: (800- 424-9065). 

### In Washington, DC: (554- 1404). Outside the USA: (Operator-202- 554-1404).

SUPPLEMENTARY INFORMATION: EPA has received the Report ofthe TSCA Interagency Testing Committee to the Administrator.

1.Background

TSCA-(Pub. L. 94-469, 90 Stat. 2003 el
seq.; 15 U.S.C. 2601 etseq.) authorizes the Administrator ofEPA to promulgate regulations under section 4(a)requiring testing ofchemical substances and mixtures in order to develop data relevant to determining the risks that such chemical substances and mixtures may present to health and the. environment.

Section 4(e) ofTSCA established and Interagency Testing.Committee to make recommendations to the Administrator ofEPA ofchemical substances and mixtures to be given priority consideration inproposing test rules under section 4(a). Section4(e) directs the Committee to revise its list of recommendations at least every 6 months as necessary. The ITC may "designate" up to50 substances and mixtures at any one time for priority. consideration by the Agency. For-such designations, the Agency must within 12 months either initiate rutlemaking or issue in the Federal Register its reasons fornot doing so. TheITC's Eighteenth Report was received by the Administrator on May 1, 1986, and follows this Notice. The'Report adds one 'substance to the TSCA section 4(e) priority list.

II.Written and Oral Comments and Public Meetings

EPA invites interested persons-to submit detailed comments on the ITC's

new recommendations. The Agency is interested in receiving information concerning additional or ongoing health and safety studies on the subject chemicals as well as information relating to the human and environmental exposure to these chemicals. A notice is published elsewhere in today's Federal Register adding the substance recommended in the ITC's Eighteenth Report to the TSCA section 8(d) Heilth and Safety Data Reporting Rule (40 CFR Part 716). The section 8(d) rule requires the reporting ofunpublished health and safety studies on the listed chemicals, This chemical will also be added to the TSCA section 8(a) Preliminary Assessment Informatiofi Rule (40 CFR Part 712] published elsewhere in this issue. The section 8(a) rule requires the reporting ofproduction volume, use, exposure, and release information on the listed chemicals.

A Focus Meeting will be held to discuss relevant issues pertaining to this chemical and to narrow the range of issues/effects which will be the focus of the Agency's subsequent activities in responding to the ITC recommendations. The Focus Meeting will be held on June 17, 1986 t EPA Headquarters, Rm. 103 NEMalil, 401 M St., SW., Washington, DC. This rae6ting isintended to supplement and expand upon written
comments submitted in response to this notice. The meeting will be held at 10

a.m.

Persons wishing to attend this meeting

or subsequent meetings on this chemical should call the TSCA Assistance Office
at the toll free number listed above at least one week in advance.

All written submissions should bear the identifying docket number (OPTS41021).

III. Status ofList

In addition to adding the one recommendation to thepriority list, the ITC's Eighteenth Report notes the .removal ofsix chemicals fromthe list since the last ITC report because EPA has responded to the Committee's prior recommendations fortesting ofthe chemicals. Subsequent to the ITC's preparation of its Seventeenth Report, EPA responded to the ITC's recommendations for six additional chemicals. The six chemicals removed and the dates ofpublication in the Federal Register ofEPA's responses to the ITC forthese chemicals are: anthraquinone, November 6, 1985 (50FR 46090); cumene,-November6, 1985 (50 FR 46104; mercaptobenzothiazole, November 6, 1985 (50 FR 46121); octamethylcyclotetrasiloxane, October 30, 1985 (50 FR 45123); pentabromoethylbenzene, November 13, 1985 (50FR 46785); sodium N-methyl-Noleoyltaurine, November 6, 1985 (50 FR 46178). The report also notes that cyclohexane and 2,6-di-tert-butylphenol, which were originally recommended with intent to.designate (50 FR 47603, November 19, 1985), have now been designated forresponse within 12 months by the ITC. 

### 18368

### Federal Register / Vol. 51, No. 96 / Monday, May 19, 1986 / Notices

The current list contains seven designated substances, one chemical recommended with intent-to-designate, and two recommended substances.

Authority: 15 U.S.C.'2603. Dated: May 6,1986. J.Merenda, Director,Existing ChemicalAssessment Division. Eighteenth Report of theTSCA Interagency Testing Committee to the Administrator,Environmental Protection Agency Summary

Section 4 ofthe Toxic Substances Control Act of1976 (TSCA,Pub. L. 94- 469) provides for the testing of
chemicals in commerce that may present

an unreasonable risk ofinjury to health

or the environment. It also provides for the establishment ofa Committee (ITC), composed of representatives from eight designated Federal agencies, to recommend chemical substances and mixtures (chemicals) to which the Administrator ofthe U.S. Environmental Protection Agency (EPA) should give priority consideration for the promulgation of testing rules.

Section 4(e)(1)(A) ofTSCA directs the Committee to recommend to the EPA Administrator chemicals to which the Administrator should give priority consideration forthe promulgation of testing rules pursuant to section 4(a). The Committee is required to designate those chemicals, from among its recommendations, to which the Administrator should respond within 12 months by either initiating a rulemaking proceeding under section 4(a) or publishing the Administrator's reason for not initiating such a proceeding. At least 6 months, the Committee makes those revisions in the-TSCA section 4(e) Priority List that,it determines to be
necessary and transmits them to the EPA Administrator.

'As a result ofits deliberations, the Committee is revisingthe TSCA section 4(e) Priority List by the addition ofone chemical, and is noting the removal of six as a result ofresponses by EPA. The Committee also is designating two chemicals that have been recommended with intent-to-designate in the seventeenth report.

The Priority List is divided into-three parts. Part A contains those recommended chemicals and groups designated forpriority consideration and response by the EPAAdministrator within 12 months. Part Bcontains those chemicals and groups recommended. with intent-to-designate. This category

was established by the Committee in its seventeenth report (50FR 47603; November 19, 1985) to take advantage of rules promulgating automatic reporting requirements for non-designated ITC recommendations under the section 8(a) Preliminary Assessment rule and the TSCA section 8(d) Health and Safety Data Reporting rule. Information received following recommendation with intent-to-designate may influence the Committee to either designate ornot designate the chemical or group of chemicals in a subsequent report to the Administrator. Part C contains chemicals and groups ofchemicals.that have been recommended forpriority consideration by EPA without being designated forresponse within 12 months.

The changes to the Priority List are presented, together with the types of testing recommended, in the following Table 1:.

TABLE I.- ADDITIONS TO THE SECTION 4(E) PRIORITY LIST-MAY 1986

Chemical/group Recommended studies

A. Designated foi

responsewithin 12 months:

Cyclohexane

(CAS No., 110-82-7). 2,6-Di-fert.

butylphenol 2 (CAS No. 128-39-2). Health Effects: Chronic toxicity including oncogenicity and neurotoxicity; teratogenicity; reproductive toxicity. Health Effects: Toxicokinetics: chronic

toxicity.

Chemical Fate: Persistence in aeroblc

and anaerobic sediments. Ecological Effects: Acute toxicity to

benthic organisms; bioconcentraton in benthic organisms.

NOTE:Cyclohexane and 2,6-Oi-terl-butylphenol were recommended with intent-to-designate bythe Committee in the seventeenth report (50 FR 47603).

B. Recommended

with intent-todesignate:

Tributyl Health Effects: Chronic toxicity includphosphate Ig oncogenic, neurotoxic, renal, re- (CAS No. productive and developmental ef126-73-8). fects. Chemical Fate: Persistence in anaerobic soils and sediments.. Ecological Effects: Chronic effects on

aquatic and terrestrial plants: chronic effects on daphnids and/or other aquatic invertebrates; acute and chronic effects on benthic organiams and soil invertebrates, if found persisent under anaerobic conditions. C. Recommended

without being designated for response within 12months:

None. CA Index

Names (9 Cl):

1. Cyclohesxane 2. Phenol. 2,6,-

bis(1,l. dimethyl ethyl). 3. Phosphoric,

acid, tributyl ester. TSCA Interagency Testing Committee" StatutoryMemberAgenciesandTheir Representatives Council onEvironmental Quality

Harvey Doerksen, Member Department ofCommerce

PatrickD.Cosslett, Member(l) Environmental Protection Agency

John D.Walker, Member and Vice

Chairperson Laurence S.Rosenstein, Alternate National Cancer Institute

Richard Adamson, Member(2) EliZabeth K.Weisburger, Alternate(3) National Institute ofEnvironmental Health Sciences James K.Selkirk, Member(4) National Institute For Occupational Safety and Health Rodger L.Tatken, Member and

Chairperson National Science Foundation

Rodger W. Baier, Member Jarvis L.Moyers, Alternate Occupational Safety and Health Administration

, . Stephen Mallinger, Alternate

LiaisonAgencies and TheirRepresentatives ConsumerProduct Safety Commission

Lakshmi C.Mishra (5) Department ofAgriculture

Richard M. Parry, Jr. EliseA. B.Brown(6) Department of Defense

. Edmund Cummings Food and Drug Administration

Arnold Borsetti National Library ofMedicine

Vera Hudson National Toxicology Program

Dorothy Canter
Committee Staff

Robert H. Brink. Executive Secretary Norma Williams,ITC Coordinator Support "Staff

Alan Carpien-Office ofthe General

Counsel, EPA

Notes

(1) Appointed on December 2,1985. (2)Appointed on October 28. 1985. (3) Appointed on October 28, 1985. (4) Appointed on February 21, 1986. (5) Appointed onDecember 13, 1985. (6)

Appointed onJanuary 6,1986. The Committee acknowledges and isgrateful for the assistance and support given the ITC by staff ofDynamac Corporation (technical support contractor) and personnel of the EPA Office ofToxic Substances. Chapter1-Introduction

1.1 Background.The TSCA Interagency Testing Committee (Committee) was established under section 4(e) ofthe Toxic Substances Control Act of1976 (TSCA,Pub. L. 94- 469). The specific mandate ofthe Committee is to recommend to the. 

### 18369

### Federal Register / Vol. 51, No. 96 / Monday, May 19, 1986 / Notices

Administrator ofthe U.S. Environmental Protection Agency (EPA) chemical substances and mixtures in commetce that should be given priority consideration for the promulgation of testing rules to determine their-potential hazard to human health and/or the environment. TSCA specifies that the Committee's recommendations shall be in the form ofa Priority List, which is to be published in the Federal Register. The Committee is directed by section 4(e)(1)(A) ofTSCA the designate those chemicals on the Priority List to which I the EPA Administrator should respond within 12 months by either initiating a rulemaking proceeding under section 4(a) orpublishing the Administrator's

reason for not initiating such a proceeding. There is no statutory time limit for EPA response regarding chemicals that ITC has recommended but not designated for response within 12 months.

At least every 6 months, the Committee makes those revisions in the section 4(e) Priority List that it determines to be necessary and transmits them to the EPA Administrator. /

The Committee is comprised of representatives from eight statutory member agencies and six liaison agencies. The specific representatives and their affiliations are named in the. front of this report. The Committee's chemical review procedures and priority recommendations are described in previous reports (Ref.1 and 2).

1.2 Committee's previousreports. Seventeen previous reports to the EPA Administrator have been issued by the Committee and published in the Federal Register (Ref. 1and 2). Ninety-one entries (chemicals and groups of chemicals) were recommended for priority consideration by the EPA Administrator and designated for
response Within 12 months. In addition, four chemicals and one group of chemicals were recommended without being so designated.

1.3 Committee'sactivitiesduring thisreporting periodBetween October 1, 1985, and March 31.1986, the Committee continued to review chemicals fromits fourth and fifth scoring exercises, and from nominations by Member Agencies, Liaison Agencies and State Agencies.

The Committee contacted chemical manufacturers and trade associations to. request information that would be of value in its deliberations. Most ofthose contacted provided unpublished information on current production,
exposure, uses, and effects of chemicals under study by the Committee.

During this reporting period, the Committee reviewed available information on 32 chemicals and 3large classes ofchemicals. One chemical was selected for addition to the section 4(e) Priority List, and 12 were deferred indefinitely. The remaining chemicals

are still under study.

On February 12, 1986, the ITC published an Intent-to-Designate notice (51 FR 5250) that listed isopropanol and described additional information needed by the ITC to reach a more informed decision on whether ornot to designate isopropanol in a subsequent report to the EPAAdministrator. A deadline of March 31, 1986 was provided for receipt ofrelevant information.

The Committee requested information

on genotoxicity, carcinogenicity, and reproductive and developmental effects

on isopropanol per se, uncontaminated with isopropyl sulfate. Information has been received indicating that some of the requested information is being developed in ongoing studies. The Committee is awaiting details on these studies and expects to make a decision

on isopropanol prior to the next report to the EPA Administrator.

In its seventeenth report to the Administrator ofEPA (Ref. 2), the ITC announced the establishmeit ofa "recommended with intent-to-designate" category, to take advantage ofrecent rules promulgating automatic reporting requirements for non-designated ITC recommendations under the section 8(a) Preliminary Assessment rule (50 FR 34805) and the TSCA section 8(d) Health and Safety Data Reporting rule (50 FR 34809). The 8(a) and 8(d) rules require the submission to EPA ofinformation on production, use, exposure and unpublished health and safety studies that may not be publicly available. The ITC noted thatinformation received following "recommendation with intentto-designate" ofa chemical or group of chemicals may influence the Committee
to either designate or not designate that chemical or group ofchemicils in a subsequent report to the Administrator.

When a chemical or group of chemicals is placed in the "recommended with intent-to-designate" category in a report to the Administrator, the ITC will review information submitted to the EPA and to the ITC following recommendation and will then take one ofthe following actions:

(a) Designate the chemical or group in the next ITC report, or

(b) Recommend the chemical or group without designation, in the next ITC report, providing a rationale for not designating the chemical orgroup, or

(c) Remove the chemical or group from the Priority List, in the next ITC report, providing a rationale forthat removal, or

(d) Defer a decision, stating the

reasons for the deferral and noting that

a decision will be announced on or before a given date.

It is anticipated that deferral ofa decision will occur infrequently. On occasion, however, the volume and/or complexity ofinformation received may make it necessary to delay a decision. Whenever the deferral option is required, it isanticipated that a final decision (Designation,Recommendation

or Removal) will be announced within 6
to 9months following the report in which the chemical orgroup of chemicals was placed in the "recommended with intent-to-designate" category.

1.4 The TSCA section4(e)Priority List.Section 4(e)(1)(B) ofTSCA directs the Committee to: ".

. .make such revisions in the [priority] list as it determines to be necessary and... transmit them to the Administrator together with the Committee's reasons for the revisions." Under this authority, the Committee is revising the Priority List by adding one chemical: tributyl phosphate. Tributyl phosphate is being recommended with intent-to-designate in this report. In addition, the Committee is designating forresponse within 12 months two chemicals that were recommended with intent-to-designate in the seventeenth report. The designated chemicals are cyclohexane and 2,6-di-tertbutylphenol. The testing recommended for these chemicals and therationales for the recommendations

are presented in Chapter 2 ofthis report.

Six chemicals are being removed from the Priority List because the EPA Administrator has responded to the Committee's prior recommendations for testing them. They are listed in the following Table 2with citations to EPA
responses: 

### 18370

### Federal Register / Vol. 51, No. 96 / Monday, May 19, 1986 / Notices

TABLE 2.-REMOVALS FROM THE TSCA SECTION 4(E) PRIORITY LIST OCTOBER 1, 1985
THROUGH MARCH 31, 1986

EPA resp Chemical/group FEDERAL REGISTER Citation

Anthraquinone

............... 50 FR 46090 Cumene

......................... 50 FR 46104 Mercaptobenzothia- 50 FR 46121

zole. Octam thylcyclotetra- 50 FR 46123

siloxare. Pentabromoethytben- 50 FR 46785

zene. Sodium N..tethyl-N- 50 FR 46178

ouoyltaurine.

Removal of81 entries was previous reports (Ref. 1 and 2 87 chemicals and groups ofch have been removed from the List.

With the one recommendat removals noted in this report,

now appear on the section 4( List. The Priority List is divid following Table 3 into three p namely, A, Chemicals and Gr Chemicals Designated forRes Within 12 Months, B. Chemic Groups ofChemicals Recoms with Intent-to-Designate, and Chemicals and Groups ofChI Recommended Without Beinj Designated for Response Wit Months. Table 3follows:

TABLE 3.-THE TSCA SECTION 4

LIST-MAY 1986

Entry

A Chemical and groups of chemicals

recommended as designated for response within 12 months:
1.Cyclohexane 2. 2.6-Di-ert-butyfphenol 3. Methyl cyclopentane 4. Tetrabromobispherto A 5. Triethylene glycol monomethyl ether 6. Triethylene glycol monoethyl ether 7.Tnethylene glycol monobutyl ether

B.Chemicals and groups o recommended with intent-toEntry

1.Tributyt phosphate

............................... C. Chemicals and groups of chemicals

recommended without being designated for response within 12months:

1.3.4-Oichlorobenzotrifluoride

................ 2. Diisodecyl phenylphosphite

..............

References

(1) Sixteenth Report ofthe TS' Interagency Testing Committee Administrator. Environmental P Agency. TSCA Interagency Test Committee. May 21. 1985, 50 FR onses

Publicationdate

Nov. 6. 1985,

Nov.6. 1985. Nov.6, 1985. Includes references to Reports 1through 15 and an annotative listofremovals.

(2)Seventeenth Report oftheTSCA Interagency Testing Committee to the Administrator. Environmental Protection Agency. TSCA Interagency Testing Committee, November 19, 1985, 50 FR47603- 47612. Chapter 2-Recommendations ofthe Committee

ct. 3, 1985. 2.1 

### Chemicalsrecommended for priorityconsiderationby theEPA
Nov.13. 1985. Administrator.As provided by section

Nov.6. 1985. 4(e)(1)(B) ofTSCA, the Committee is adding the following chemical substance
to the section 4(e) Priority List: Tributyl
noted in phosphate. The recommendation of ).To date. tributyl phosphate is being made after
hemicals considering the factors identified in Priority section 4(e)(1)(A) and other relevant information, as well as-the professional
ion and six judgment of Committee members. In 10 entries addition, the Committee is designating
e)

Priority forresponse within 12 months two ed in the chemical substances that were 'arts; recommended with intent-to-designate
oups of in the seventeenth report. The

sponse designated chemicals are cyclohexane als and and 2,6-di-tert-butylphenol. nended 2.2 Chemicalsdesignated for C, responsewithin 12months. emicals 2.2.a Cyclohexane. In the seventeenth report to the hin 12 Administrator ofEPA (50FR 47603), cyclohexane was recommended with intent-to-designate. The rationale for (e) PRIORITY thatrecommendation appears in the seventeenth report. Information
Dateof reviewed by the Committee in response designation to the seventeenth report included any public comments on the Committee's recommendations; production volume,
use, exposure, and release information May 1986. reported by manufacturers of May 1986. cyclohexane under the TSCA section May 1985. may 1985. 8(a) Preliminary Assessment rule; health May 1985. and safety studies submitted under the May 1985. TSCA section 8{d} Health and Safety May 1985. Data Reporting rule; and any unpublished and published data fchemicals available to the Committee. The designate: information included acute toxicity studies, skin and eye irritation studies

Date ot and additional genotoxicity studies recommendation 

### (Phillips Petroleum Co., 1986). Summary
data from acute toxicity, skin irritation May 1986 and repeated dose (sixmonths) studies

were also received from other submitters (Eastman Kodak Co., 1986; May 1985. Dow Chemical Co., 1986). Although November 1985. 

### ecological effects testing was not recommended for cyclohexane, information dealing with environmental

CA persistence also was received (Shell Oil

tothe Co., 1986).
rotection" After reviewing the information, the ing Committee concluded that data are still
20930-20939. lacking on chronic (two-year) effects, especially oncogenicity and neurotoxicity. Teratogenic and reproductive effects studies also are absent. Forthese reasons and for the

reasons previously presented (50 FR 47603) the Committee is now designating cyclohexane forresponse within twelve months and recommending that itbe tested for the following:

Health Effects: Chronic effects including oncogenicity and neurotoxicity (with special emphasis on neuropathology.

Teratogenicity and reproductive toxicity.
References

(1)Dow Chemical Co., Midland. MI. Letter fromL.Hampton toDocument Control Officer,U.S. EPA.January 31.1986.

(2)Eastman Kodak Co., Rochester, N.Y. Letterfrom R.L.Raleigh to U.S. EPA.January 15, 1986.

(3)Phillips Petroleum Co..Bartlesville, OK. Letter from J.R. Rust to Document Control Officer/OPTS, U.S.EPA. January 15, 1986.

(4)Shell Oil Co., Washington,DC.Letter from E.L.Hobson to U.S. EPA.February 5, 1986.

2.2.b 2,6-Di-tert-butylphenol. In the seventeenth report to the Administrator ofEPA (50 FR 47603), 2,6- di-tert-butylphenol was recommended with intent-to-designate. The rationale forthat recommendation appears in the seventeenth report. Information reviewed by the Committee in response to the seventeenth report included any public comments on the Committee's recommendations; production volume,
use, exposure and release information reported by manufacturers ofZ,6-di-tertbutylphenol under the TSCA section 8(a) Preliminary Assessment rule; health and safety studies submitted under the TSCA section 8(d) Health and Safety Data Reporting rule; and any unpublished and published data available to the Committee. The information included data on acute oral and percutaneous LD50 studies with rats; skin and eye irritation with rabbits; skin depigmentation, skin sensitization and delayed contact hypersensitivity with guinea pigs; rat hepatocyte primary culture and DNA repair tests; an Ames Salmonellamicrosomal assay; intravenous toxicity to mice and a report

on the physiological response of experimental animals to the absorption of alkylated phenols and anilines (CibaGeigy, 1986; DuPont, 1986; Ethyl, 1986; Shell, 1986). Also included was a suminary on ecological effects (Dow, 1986).

After reviewing the information, the Committee concluded that data are still lacking on toxicokinetics, chronic toxicity, persistence in sediments, acute 

### 18371

### Federal Register / Vol. 51, No. 96 / Monday, May 19, 1986*/ Notices

toxicity to benthic organisms and bioconcentration inbenthic organisms. For these reasons and for thereasons previously presented (50 FR 47603) the Committee isnow designating 2,6-ditert-butylphenol for response within twelve months and recommending that it be tested forthe following: Chemical Fate: Persistence in aerobic and anaerobic

sediments Health Effects: Toxicokinetics and chronic toxicity Ecological Effects: Acute Toxicity to benthicorganisms Bioconcentration in benthic organisms

References

(1)Ciba-Geigy. Ciba-Geigy Corp., Ardsley, N.Y. Letterfrom A. DiBattista to U.S. EPA. February 12, 1986.

(2)Dow. DowChemical Co., Midland, MI. Letter from L. Hampton to U.S. EPA. January •31, 1986. (3)

DuPont. E.I. DuPont deNemours and Co.,Wilmington, DE.Letter from K.D. Dastur to U.S.EPA.January 14,1986.



### (4) Ethyl. EthylCorporation,Baton Rouge, LA.Letter from L L.Weir to Document .Control Officer, Office ofPesticides and Toxic Substances, U.S. EPA.February 4,1986.

(5)Shell. Shell Oil Co., Washington, DC. Letter from E. L. Hobson to U.S. EPA. February 5,1986.



### 2.3. Chemicalsrecommendedwith intent-to-designatebutnot designated forresponsewithin 12months. 2.3.a Tributyl Phosphate. Summaryofrecommendedstudies.It is recommended that tributylphosphate 

### (TBP)be tested for the following:

A.Chemical Fate: Persistence in anaerobic soils and sediments.

.B. Health Effects: Chronic toxicity including oncogenic, neurotoxic, renal, reproductive and developmental effects.

C. Ecological Effects: Chronic effects



### on aquatic and terrestrial plants; " Chronic effects on daphnids and/or other aquatic invertebrates.

Acute and chronic effects on benthic 

### organisms and soil invertebrates, depending on the results from persistence studies

### PhysicalandChemicalInformation

CAS Number: 126-73-8. Synonyms: Phosphoric acid, tributyl
ester (9C);TributoXyphosphine oxide; 

### Tri-n-butyl phosphate.

Acronym: TBP.
Structure:

O-CH 2CCB 2 CH2 3


### 0 = 

### P 0CH 2

### CH 2

### CH 2

### CH 3


### O-CH2

### CH 2

### CH 2

### CH 3 Empirical Formula: C 12H 270 4P. Molecular Weight: 266.32. Melting Point: <-80°C (Ref.47, TDB, 1986).

Boiling Point: 289*C at 760 mmHg 

### (Ref. 11, CRC, 1983).

Vapor Pressure: 7.3 mmHg at 150*C (Ref. 23, Laham et al., 1984); 0.07 mmHg at 25°C (estimated; Ref. 48, U.S. EPA, 1985).

Air Vapor Density: 9.2 (Ref. 28, Monsanto, 1985).

Solubility in Water: 420 mg/L at 25°C (Ref.17, General Electric, 1983); 280 mg/ L (Ref.39, Saeger et al., 1979).

Solubility in Organic Solvents: Soluble in ether, benzene carbon disulfide, ethanol, mineral oil, and gasoline (Ref. 11, CRC, 1983).

Specific Gravity: 0.977-0.978 at 20/ 20°C (Ref. 28, Monsanto, 1985).

Log Octanol/Water Partition Coefficient (log P): 4.0 (Ref.39, Saeger et al., 1979); 2.36 (Ref. 20, Hansch and Leo, 1979).

Description ofChemical (ambient conditions): Clear, colorless, odorless liquid (Ref.47, TDB, 1986).

Rationale for Recommendations

I. Exposure information-A. Production/use.. There are at least three, and maybe as many as five, manufacturers ofTBP in the United States. CEH(1981, Ref. 8) reported that :atleast 5 millionpounds ofthe compound were produced in 1979. Annual production since then has been reported at 3million pounds for'1982 and estimated at 3 million pounds for 1983 (Ref.9, CEH, 1983). Current annual production has been estimated at 3.to 5 million pounds (Ref. 48, U.S. EPA, 1985.)

A major use ofTBP isas a nonflammable component ofhydraulic fluids in the control systems of

- commercial aircraft, Industrial fluids

and lubricants account for another large share. Liquid phosphate esters are the basestocks for fire-resistant oils used in die-casting, air compressors, gas turbines, and many-other applications. TBP may also be used as a solvent/ plasticizer for certain polymers, an industrial solvent, an antifoam agent, .rand a pigment grinding assistant.It has been estimated (Ref. 28, Monsanto, 1985) that about 24 percent goes into hydraulic fluids, 50 percent into uses as a plasticizer, and 26 percent for miscellaneous uses.

B. Occupational exposure.The National Occupational Hazard Survey, conducted in 1972, estimated that 323,477 workers were potentially exposed to TBP in the workplace (Ref. 31, NIOSH, 1976). Preliminary data from the National Occupational Exposure Survey indicate that, in 1980, 12,111

-

- • workers (including 427 women) were potentially exposed to the compound in

- the workplace (Ref. 32, NIOSH, 1984). The following limits have been established for workplace airborne concentrations ofTBP:

8-hourTWA-PEL 5 mg/m 3 (Ref. 34, OSHA, 1985).

8-hourTLV-TWA 2.5mg/m 3 (0.2 ppm) (Ref.2,ACGIH, 1985).

C. Environmental release.It is likely that most TBPis released to surface
waters from industrial effluents and from the release ofhydraulic fluids to storm drains and drainage ditches and
to land and water via landfill disposal of oil wastes and plastics.

There is considerable evidence for widespread, low-level environmental
exposures to TBP. It has been detected in fish and human lipid tissues, in municipal and industrial effluents, river water, estuarine water, ground water, drinking water, snow, and sediments. LeBel and Williams (1983, Ref. 25) analyzed 16 human adipose tissue samples from cadavers and found TBP at 9.0 ng/g, on an extracted fat basis, in the tissue from one cadaver. Dunlap et al. (1979, Ref.14) found TBP at 1.7 ug/L in ground water below a landfill. Grob and Grob (1974, Ref. 18) measured TBP in water at or near Zurich, Switzerland, and found concentrations of 10 to 82 ng/ L.Zoeteman et al. (1981, Ref. 51) measured TBP inground waters in the Netherlands at 0.01 to 0.1 ug/L. Meijers and van der Leer (1976,Ref. 26) found TBP at up to 10 ug/L in the Waal River in the Netherlands. Sheldon and Hites (1978, Ref.42) reported finding TBP in Delaware River water at 60 to 2,000 ng/ L. Shackelford et al.(cited in U.S. EPA, 1985, Ref.48) reported findingTBP in plant effluents form a variety of industries. Mean concentrations were from 15 ug/L to 1,880 ug/L. Williams and LeBel (1981, Ref. 50) examined drinking
water form 29 municipalities across Canada and found-measurable TBP in samples from each location, as well as in water formthe Atlantic and Pacific Oceans, the Great Lakes, Lake Winnipeg, the St.Lawrence River, and the Columbia River. Concentrations ranged from*0.2 to 62 ng/L. Piet et 

### al. (1981, Ref. 36) identified TBP at 100 ng/L in drinking Water processed from surface water using sand filtration. The unfiltered water had no detectable T13P.
TBP appears to be found nearly everywhere in the environment at low concentrations. No information was found on the natural occurrence ofTBP.

II.Chemical fate information-A. Transport. TBP has moderate solubility in water and moderate vapor pressure at

- ambient temperatures. It also has a 

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### Federal Register ./ Vol. 51, No. 96 / Monday, May 19, 1986 / Notices

moderate log P value (4.0,measured). The physical and chemical
. "
characteristics-of TBP indicate that it wil partiti6n throughout the-environment and appearatmost everywhere, including biolipids'

B. Persistence. A study ofthe primary biodegradation ofTBP by a river water die-away method (Ref. 39, Saeger et al., 1979) found 50 percent loss ofthe parent compound in about 3.5 days and complete loss in 7days. These.same investigators, using a carbon dioxide evolution method, also reported CO2 evolution at30 percent oftheory in 7 days and 81 percent oftheory in 28 days. Initial concentrations ofTBP in the test units were 1 and 20 mg/L, respectively. These results indicate relatively rapid and complete biodegradation ofTBPis aerated surface waters. There was no evidence ofnonbiological degradation of TBP in sterile controls. Francis et al. (1980, Ref. 15) observed no anaerobic biodegradation ofTBP incubated for 30 days at 28*C with anaerobic bacteria isolated from a waste disposal site. No other information on anaerobic biodegradation was found., and the potential for anaerobic biodegradation must be considered unknown.

Hydrolysis is very slow at most environmental pH's (Ref.48, U.S. EPA. 1985). Atmospheric oxidation is not expected to be significant.

C. Rationale forchemical fate recommendations.Because ofits moderate water solubility, log P, and vapor pressure, TBP should partition to natural waters, soils and sediments, biota, and air. TBP appears to be' biodegraded rapidly and 1completely.in aerobic surface waters. Its fate in soils and sediments isnot clear. Itis likely to persist in the atmosphere until returned
to earth by virtue ofits high vapor density or in precipitation. TBP that partitions to biota may become a part of the food chain.The ubiquitous environmental appearance ofTBIP at low concentrations may mean that it is not effectively degraded below some threshold concentration or that the continuous release ofTBP into the environment leads to some low-level equilibrium concentration reflecting both input and removal processes. The monitoring evidence, showing widespread low concentrations ofTBP, justifies the consideration ofpotential environmental effects resulting from continuous, low-level exposures. Tests should be conduct9d to evaluate the persistence ofTBP in anaerobic sediments and soils.

111. Biological effects of concern to human health-A.Metabolismand toxicokinetics.Suzuki et al. (1984. Ref. 46) sttidied the excretion and '..... biotransformation ofTBPin.rats. In animals dosed with [ 4C]-TBP, 66 percent ofan oral dose and 81 percentof

an intraperitoneal dose were excreted in 24 hours. The two major metabolities present in urine were the hydrolysis products dibutyl and monobutyl phosphates. Other metabolites present were the result ofoxidation ofthe butyl chain.

The effect ofTBP on enzyme activity in rats has been studied by Oi*shi et al. (1980, Ref. 33). In animals fed a diet containing 0.5 or 1percent TBP for 10 weeks, serum transaminase and alkaline phosphatase activities were significantly decreased. There was no difference in cholinesterase activity in
serum, whereas brain cholinesterase activity was significantly increased. Blood coagulation time was significantly prolonged.

B.Acuteandsubchronic(short-term) effects. The acute effects ofTBP have been studied by Smyth Carpenter (1944, Ref.43), Chambers and Casida (1967, Ref. 10), Vanedkar (1957, Ref.49), Suzuki
et al. (1977, Ref. 45), Sabine and Hayes (1952, Ref. 38), Johannsen et al. (1977, Ref. 21), and Mlitomo et al. (1980,Ref. 27). Sites and biological effects-of acute testing were paralysis due to weak cholinesterase inhibition, anesthetic effect, skin and mucous membrane irritation, lung edema, and degeneration ofkidney tubules.

Laham et al. (1983. Ref. 22) studied the effect ofTBP in rats fed 0.28 and 0.42 mL/kgTBP by gavage for 14 days. In the high-dose group, a significant (p<0.05) reduction ofcaudal nerve conduction velocity accompanied by morphological changes inthe sciatic nerve were observed in males.In both sexes ofthe high dose groups, electron microscopy showed a retraction of Schwann cell processes of the surrounding sciatic unmyelinated fibers, indicating an early response to a chemical insult.

In another study, Laham et al. (1984, Ref. 23) administered TBP by gavage to rates at concentrations of0.14 and 0.42 mL/kg for 14 consective days. In the high dose group, a significant decrease inhemoglobin in females, a low incidence ofdegenerative changes in the
testes in males, significant changes in amylase and triglyceride activity in females and an increased amylase activity in males were observed. In addition, a significant increase in potassium level was observed in females both low- and high-dose groups.

Mitomo et al. 1(1980, Ref. 27) studied the effects ofTBP on rats and mice that

were fed TBP daily ii their diets at con.cen-trations of0, 0.05, 0.2, and 1.0 percent for 3 months. Results ofthe studies showed a dose-dependent derpression inbody weight gaifi; an increase in liver, kidney, and testes weights; a decrease in uterus weightand ari incieAse in blood urea nitrogen valu s;in both'rhice and rats at high-' dose levels.'Diar'rhea was alio 'observed: Similar effects were seen in9- and 10- week studies when TBP was fed to rats (Ref. 33, Oishi et al., 1980).

Cascieri et al. (1985, Ref. 7)fed rats diets cohtaining TBP at levels of0, 8,40, 200, 1,000 or 5,000 ppm for 90 days. Significant changes were seen in blood parameters and liver weight at the highest dose. Urinary bladder cell hyperplasia was observed in both sexes at the-highest dose. At 1,000 ppm it was only noted in the males.

In a recent study, TBP was administered by gavage over an 18-week period to rats.Low-dose animals received 0.20 g/kg/day throughout the experiment and the high dose animals received 0.30 g/kg/day forthe first six weeks. For the remaining twelve weeks, thehigh-dose level was increased to0.35 g/kg/day. All testrats examined developed diffuse epithelial hyperplasia of the urinary bladder (Ref. 24, Laham et al., 1985). C. Genotoxicity.Hanna and Dyer (1975, Ref.19) tested tributyl phosphate in S. typhimurium,E.coli and Drosophila. Nomutagenic effects were observed.

D. Oncogenicity.No information was found. Trimethyl phosphate, a structural analog, was tested for carcinogenicity in
rats and mice (Ref. 30, NC, 1978). It induced adenocarcinomas ofthe endometrium in female mice and benign fibromas ofthe subcutaneous tissue in male rats. .

E. Reproductiveanddevelopmental. effects. When tested inchicken eggs, TBP was found to be weakly teratogenic (Ref. 37, Roger et al., 1969). No mammalian reproductive and developmental effects information was found inthe literature searched.

F. Chronic(long-term)effects. No information was found.

G. Observationsinhumans.Workers exposed to 15 mg/m3 ofTBP complained ofnausea and headache (Ref. 1.ACCIH, 1980). The principal routes ofexposure

are skin contact and inhalation. Signs of exposure include nausea, headache,. irritation ofthe eyes and dermatitis (Ref. 44, Stauffer, 1984).

14. Rationale forhealtheffects recommendations. Thousands of workers and consumers are potentially exposed to TBP. There is a potential for human exposure to low levels of TBP due to its uses as a flame retardani in aircract hydraulic fluid, for uranium. extraction, as an industrial solvent, and 

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as a plasticizer. TBP has been detected
at low levels,in municipal and industrial effluents, sediments, and inriver, estuarine, ground, and drinking waters. It has also been detected in human and fish lipid tissues.

Available information on health effects are limited to acute and subchronic effects. In view of the lack of information on the chronic health effects ofT13P, the induction ofurinary bladder hyperplasia and the carcinogenic effect oftrimethyl phosphate, studies-on chronic toxicity, including oncogenic, neurotoxic, renal, and reproductive and developmental effects, are recommended.

IV. Ecological effects of concern.-A. Acute andsubchronic(short-term) effects. TBPproduces acute

. toxicity with a variety ofaquatic organisms, at low mg/L concentrations, as shown in Table 4. TBP inhibits the growth ofsome

TABLE 4.-ACUTE TOXICITY TESTS WITH A VARIETY OF AOUATIC ORGANISMS

24 -hr 48 hr 72=hr g6-hr Organism LC,o LC. LC. LC. Reference (mg/LI (mg/L) (mg/L) (mg/L)

Rainbow trout

......................................................................................................... 5to 9 Dave and Lidman (1978, Ref. 12). Rainbow trout

........................................... .............................................................. 11.0 M onsanto (1985, Ref. 28). Zebrafish

.................................................. . 11.4 11.4

..................... 11.4 Dave et al. (1981, Ret. 13). Goldfish

.......................................................................... ................ ............ 8.8 Sasaki el at. (1981), Ref. 40) Killfish..........

......................................... 9.6 Sasaki et al. (1981), Re. 40). Fathead minno

............................. ................ 6.4 Monsanto (1985, Ref. 28).

Chlorelta

..... ........................ 5to 10.......

........... AQUIRE (1986, Ret. 3). Daphnia

.................................................. 12.8 3.7 2.1

........... Dave et al. (1981, Ret, 13).

B. Chronic(long-term)effects. Penman and Osborne (1976, Ref. 35) reported that TBP, at dosesof0.1 to:0.2 percent, had no reproductive effects on the two-spotted spider mite. A related compound, trimethyl phosphate, produced reproductive effects on guppies, toads, quail, and mites, all at relatively high doses (Ref.48,U.S. EPA, 198.5].

C. Otherecologicaleff'ects(biological, behavioral, orecosystemprocesses). Bringmann and Kuhn (1982, Ref.6) determined effects concentration (EC) values for immobilization ofDaphnia
magna.The EGo, EC5o, and ECteo were 5, 30 and 41 mg/L, respectively.



### D.Bioconcentrationand food-chain transport. Given its octanol/water partition coefficient, TBP is likely to partition into lipids of biota. Saeger et 'al. (1979, Ref. 39) calculated a bioconcentration factor of 190. Sasaki et al. (1981, Ref. 40) studied the absorption and elimination ofphosphoric acid esters bykillifish and goldfish. "'hey found that the amount ofTBP in the fish varied with the.species and that. bioconcentration in the killifish was about three times greater than in goldfish, using a static water system.

In a followup study,using continuousflow systems Sasaki et al. (Ref.41, 1982) found TBP taken up rapidly by killifish and reaching a steady-state concentration within I day. It remaitied
at that concentration during 38 days of
exposure. The bioconcentration ratio during this time was almost constant, varying from 21 to 35. When exposure to TBP was stopped, elimination was very rapid, with halfgone within 1.25 hours and no detectable TBP after 24 hours.

E. Rationale forecologicaleffects recommendations. The available information shows that TBP has acute effects on a variety ofaquatic organisms at moderately low concentrations (low parts per million). TBP also has been found acutely toxic to terrestrial plants
at 5,000 ppm. Nevertheless, there is low

concern for the acute effects of TBP since it does not appear that TBP will persist in aerobic environments at concentrations likely to cause acute effects to biota. However, it does appear that nearly all biota are continuously exposed to low concentrations ofTBP and the long-term effects ofthat algae at concentrations of3 to 10 mg/L (Ref.48,.U.S. EPA, 1985). Bringmann and Kuhn (Refs. 4 and 5, 1978, 1980) found that TBPinhibited the growth ofan Entosiphonprotozoa sp. at 14 mg/L,a Scenedesmusalgal sp. at 3.2 mg L, and

aMicrocystisbacteria sp. at 4.1 mg/L.

Gast and Early (1956, Ref. 16) investigated the phytotoxicity ofseveral solvents by dipping plant foliage quickly into solutions ofthe solvents and observing the effects. Of 86 solvents investigated, TBP was the most toxic. Exposure to a 0.5 percent solution of TBPkilled all of the six species tested, including bean, corn, cotton, cucumber, tobacco, and tomato.

TBP applied to vegetation reduced the growth ofthe roots ofrice, radish, and soybean plants at concentrations of10
to 100 ug/g ofsoil (Ref.29, Muir, 1984).

,A single-dose oral LDo for the white leghorn adult hen was reported as 1.8 g/ kg (Ref.21, Johannsen et al., 1977). exposure are largely unknown. The
acute toxicity data with terrestrial plants and algae and the growth inhibition observed with rice, radish, and soybeans lead tothe conclusion .that long-term studies need to be conducted with both aquatic and terrestrial plants exposed to TBP at low concentrations. The data from the acute daphnid tests by Dave et al. (1981, Ref. 13) showed a high ratio between the 24- and 48-hour LCso's (12.8/3.6=3.5), suggesting potential chronic effects. Long-term studies, using low TBP concentrations, should be conducted with daphnids and/or other aquatic invertebrates. If anaerobic persistence studies indicate long half-lives forTBP 'in soils and sediments, bioassays should be conducted with representative benthic organisms and soil invertebrates.
References

(1)ACGIH. "Documentation of the Threshold Limit Values." 4th Ed. Cincinnati, OH: American Conference ofGovernmental Industrial Hygienists (1980).

(2)ACGIII. "TLV's. Threshold Limit Values and Biological Exposure Indices for 1985-86." Cincinnati, OH: American Conference of Governmental Industrial Hygienists. p. 31 (1985].

(3] AQUIRE. Aquatic Information Retrieval Database [data base]. Baltimore, MD: Chemical Information Systems, Inc. (1986).

(4] Bringmann. G.and Kuhn, R."Testing of substances for theirtoxicity threshold: Model organismsMicrocystis(Diplocystis aeruginosaand Scenedesmusquadricauda." MitteihingenInternationa/eVereinigung fuer Linnologie.21:275-284 11978.

(5)Bringmann, G. and Kuhn, R. "Comparison of the toxicity thresholds of water pollutants tobacteria, algae, and protozoa in the cellmultiplication inhibition test," WaterResearch.14:231-241 (1980).

(6] Bringmann, G.and Kuhn, R."Ergebnisse du schadwirkung wassergefahrdender stoffe gegen Daphniamagnain einem weiterentwickelten standardisierten testverfahren," Zeitschrift fuer Wasserund AbwasserForschung.15:1-7 (1982).

(7)Cascieri,T., Ballester, E.l., Seaman, L.R., McConnell, R.F., Thackara, J.W. and Fletcher, M.l. "subchronic toxicity study with tributyl phosphate inrats," The Toxicologist5:97 (1985).

(8)CEIH1. ChenicalEconomicsHandbook. Stanford Research Institute, Menlo Park, CA: SRI International. Section 579.5022R. 579.5023.C (1981).

198] CElIH. ChemicalEconomicsHandbook. Stanford Research Institute, Menlo Park, CA: SRI International. Sections 760.9000Q, 760.9002N,O, 760.9003J (1983).

(10) Chambers, H.W. and Casida, I.E. "Protective activity ofnicotinic acid derivatives and their 1-alkyl-2-and 1-alkyl-6- pyridones against selected neurotoxic agents," Toxicology and Applied Pharmacology.10:105-118 (1967). 

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### No. 96 

## / Monday, May 19, 1986 

## / Notices

(11) CRC. CRCHandbookofChemistryand Physics.64th Ed. Boca Raton. FL: CRC Press, Inc. (1983).

(12) Dave,'G. and Lidman, U. "Biological and toxicological effects ofsolvent extraction chemicals. Range finding acute toxicity in the rainbow trout (Salmogairdneri Rich.) and in the rat (RattusnorwegicusL,)," Hydrometallurgy.3:201-216 (1978).

(13) Dave, G.. Andersson, K., Berglind. R.. and Hasselrot, B. "Toxicity ofeight solvent extracton chemicals and ofcalcium to water fleas, Dophniamagna,rainbow trout, Salmo gairdneri, and zebrafish, Brachydaniorerio," Comparative BiochemicalPhysiology.69:83- 98 (19811.

(14) Dunlap, W.I., Shew, D.C., Scalf, M.R.. Cosby, R.L.. and Robertson, ).M. "Chapter 27-Isolation and identification oforganic contaminants inground water,". IdentificationandAnalysis ofOrganic Pollutantsin Water.(AnnArbor, MI: Ann Arbor Science, 1976).

(15) Francis, A.J., Dobbs, S., and Nine, B.]. "Microbial activity oftrench leachates from shallow-land low-level radioactive waste disposal sites," AppliedandEnvironmental Microbiology. 40:108-113 (1980). (16) Cast, R. and Early J."Phytotoxicity of solvents and emulsifers used in insecticide formulations," AgriculturalChemicals.April: 42-45, 136-137, 139 (1956).

(17) General Electric. General Electric Material Safety Data Sheet (October 1983).

(18) Grab, K. and Grob, C. "Organic substances in potable water and in its precursor. Part IL. Applications in the area of Zurich," JournalofChromatography, 90:303- 313 (1974).

(19) Hanna, P.). and Dyer, K.F. "Mutagenicity oforganophosphorous. compounds in bacteria and Drosophila," MutationResearch,28:405-420 (1975).

(20) Hansch, C. and Leo, A. Substituent Constants forCorrelation Analysis in ChemistryandBiology(New York: John Wiley &Sons, 1979).

(21) johannsen, F.R., Wright, P.L., Gordon, D.E., Levinskas, G.J., Radue, R.W. andGraham, P.R. "Evaluation ofdelayed neurotoxicity and dose-response relationships ofphosphate esters in the adult hen," ToxicologyandAppliedPharmacology. 41:291-304 (1977).

(22) Laham, S., Szabo,I.,and Long.G. "Effects oftri-n-butyl phosphate on the peripheral nervous system ofthe SpragueDawley rat," DrugandChemicalToxicology. 6:363-377 (1983). 1

(23) Laham, S., Long, G., and Broxup, B. "Subacute oral toxicity oftri-n-butyl phosphate in Sprague-Dawley rat," Journalof Applied Toxicology.4:150-154 (1984).

(24) Laham, S., Broxup. R.. and Long, G. "Induction ofurinary bladder hyperplasia in Sprague-Dawley rats orally administered trin-butyl phosphate," Archievesof Environmental Health,40:301-306 (1985). (25) LeBel, G.L. and Williams. D.T. "Determination oforganic phosphate triesters in human adipose tissue," Journal ofthe AssociationofOfficialAnalyticalChemists. 66:691-698 (1983).

(26) Meiiers, A.P. and van der Leer, R. Chr. "The occurrence oforganic micropollutants in the river Rhine and the river Maas in 1974," WaterResearch.10:597-604 (1976). (27) Mitorno, T., Ito, T., Ueno, Y., and Terao, K. "Toxicological studies on.tributyl phosphate. [I) Acute and subacute toxicitios,." Journal ofToxicologicalSciences. 5:270-271 (1980).

(28) Monsanto. A letter fr6m H.M. Keating, Monsanto Industrial Chemicals Co., St. Louis, MO. toT. O'Bryan, Information Management Division, Office ofToxic Substances. U.S. Environmental Protection Agency, Washington, DC (April 4, 1985).

(29) Muir,D.C.G.."Phosphate esters," The HandbookofEnvironmentalChemistry,Vol. 3,Part C.O. I-utzinger, ed. (New York: Springer-Verlag, 1984).

(30) NCI. National Cancer Institute. 'Bioassay of trimethyl phosphate for possible carcinogenicity," CAS No. 512-56-1 NCI-CGTR-41 (1978).

(31) NIOSH. "National Occupational Hazard Survey (1972-1974)" Idata base!. Cincinnati, OH: Department ofHealth and Hunjan Services, National Institute for Occupational Safety and Health (1976).

(32) NIOSH. "National Occupational Exposure Survey (1980-1983)" [data base. Cincinnati, OH: Department ofHealth and Human Services, National Institute for Occupational Safety and Health (1984).

(33) Oishi, II, Oishi, S., and Hiraga, K: "Toxicity of tri-n-butyl phosphate With special reference to organ weights, serum components and chlorinesterase activity in male rats," ToxicologyLetters.6:81-85 (1980).

(34) OSHA. "OS-IA Safety and Health Standards forGeneral Industry." 29 CFR 1910. Subpart Z. U.S. Department ofLabor, Occupational Safety and Health Administration. Washington, DC: U.S. Government Printing Office. p. 653 (1985).

(35) Penman, D.R. and Osborne, G.O. "Trialkyl phosphates and related compounds

as antifertility agents ofthe two-spotted spider mite," Journal ofEconomic Entomology. 69:266-268 (1976).

(36) Piet, G.)., Morra, C.H.F., De Kruijf, H.A.M., Schultink, LI., and Smeenk, J.G.H.M. "The behavior oforganic micropollutants during passage through soil," Studiesin EnvironmentalScience. 17:557-564 (1981),

(37) Roger, J.C., Upshall, D.G., and Casida, J.E. "Structure activity and metabolism studies on organophosphate teratogens and their alleviating agents indeveloping hen eggs with special emphasis on bidrin," BiochemicalPharmacology.18:373-392 (1969).

(38) Sabine, J.C. and Hayes, F.N. "Anticholinesterase activity oftributyl phosphate," AMA Archives ofIndustrial HygieneandOccupational Medicine.6:174- 177 (1952).

(39) Saeger, V.W., Hicks 0., Kaley, R.G., Michael, P.R., Mieure, J.P., and 'rucker, E.C. "Environmental fate of selected phosphate esters," EnvironmentalScience and Technology.13:840-844 (1979).

(40) Sasaki, K., Takeda, M., and'Uchiyama, M. "Toxicity, absorption and elimination of phosphoric acid triesters by killifish and goldfish," Bulletih6fE,'ironmental
ContaminationToxicology.27:775-782 (1981).

(41) SasakiK., Suzuki, T., Takeda, M., and Uchiyama, M. "Bioconcentration and excretion qfphosphoric acid triesteirs by killifish (Oryzeas latipes),"Bulletinof Environmental Contamination and Toxicology. 28:752-9 (1982).

(42) Sheldon, L.S. and Hites, RA "Organic compounds in the Delaware River," EnvironmentalScience andTechnology. 12:1188-1194 (1978).

(43) Smyth, H.F. and Carpenter, C.P. "The place ofthe range finding test in the industrial toxicology laboratory," Journalof Industrial HygieneandToxicology, 26:269- •273 1944). (44) Stauffer. Stauffer Chemical Co., Product Safety Data Sheet, (1984).

(45) Suzuki, Y., Kikuchi, H., Kato, C., Horiuchi, Y., Tomita, K., and Hashimoto, Y. "Effect of alkyl phosphates on /3- glucuronidase in rats; released of,- glucuronidase from liver microsomes into serum," BiochemicalPharmacology, 26:881- 885 (1977).

(46) Suzuki, T., Saski, K., Takeda, M., and Uchiyama, M. "Metabolism oftributyl phosphate in male rats," Journalof Agricultural andFoodChemistry.32:603-610 (1984).

(47) TDB. Toxicology Data Bank [data bank]. Bethesda, MD: National Library of Medicine, U.S. Department ofHealth and Human Services (1986).

(48 U.S. EPA. Chemical Hazard Information Profile (CHIP). Draft report on 'tri(alkyl/alkoxy) phosphates. Washington, DC (September 23, 1985). ,

(49) Vandekar, M. "Anesthetic effect produced by organophosphorus compounds," Nature.179:154-155 (1957).

(50) William, D.T. and LeBel, G.L. "A national survey oftri-(haloalkyl)-, trialkyl-, and triarylphosphates in Canadian drinking water," BulletinofEnvironmental ContaminationToxicology. 27:450-457 (1981).

(51) Zoeteman, B.C.J., DeGreef, E., and Brinkmann, F.J.J."persistency oforganic contaminants in groundwater, lessons from soil pollution incidents in The Netherlands," The Scienceofthe TotalEnvironment. 21:187-202 (1981).

2.4 Chemicalsand groupsof chemicals recommendedwithoutbeingdesignated for
responsewithin 12months.Non&.
(FR Doc, 86-11070 Filed.5-16-86; 8:45 aml

BILLING CODE 6560-50-M

[OPTS-51621; FRL-3012-S] Certain Chemicals Premanufacture

Notices

Correction

In FR Doc, 86-10015, beginning on page 16587, in the issue ofMonday, May 5, 1986, makethe following corrections:

1. On page 16588, first column, under "P86-931", fifth line,. "1,1000-2,000" should read "1,000-2,000".

2. On page 16589, first column, under "P86-946", sixth line; "5/kg" should read "5 g/kg".

3. On the same page, second column, under "P86-948", sixth line "g/kg" should read "5-g/kg".

BILLING CODE 1505-01-M I m i " , , ...................... . . . .. ......... 

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