Jump to main content.


Index of Cleared Science Reviews for Diquat (Pc Code 032202)

You will need Adobe Reader to view some of the files on this page. See EPA's PDF page

April 25, 1967. Review. 6 Page(s).
Ronald Ney. Efficacy & Ecological Effects Branch.
Evaluation of Pesticide Petition Number 7F0594. 6,7-dihydrodipyrido (1,2-a:2',1'-c)
pyrazidiinium (Diquat). Submitted by Chevron Chemical Company. Filed April 10, 1967.
Manufacturing process information on page 1 is not included.
Document (PDF) (238 KB PDF).

September 06, 1973. Letter. 2 Page(s).
Edward Gross. FR Documents Coordination Branch.
Pesticide Petition No. 1F1101. Food Additive Petition No. 3H5022.
Document (PDF) (117 KB PDF).

January 14, 1974. Memorandum. 4 Page(s).
Don Duffy. Chemistry Branch.
PP #1F1101 and FAP #3H5022. Aquatic Uses of Diquat. Evaluation of Amendment of 10/4/73.
Document (PDF) (48 KB PDF).

April 09, 1974. Review. 1 Page(s).
Ronald Ney. Efficacy & Ecological Effects Branch.
Environmental Chemistry Evaluation of Diquat Dibromide (6,7-dihydrodipyrido(1,2-a:2;1'-C)
pyrazinedirum dibromide). PP #4G1470. Submitted by Chevron Chemical Co. 1/29/74.
Document (PDF) (48 KB PDF).

May 14, 1974. Memorandum. 8 Page(s).
John Worthington. Chemistry Branch.
PP #4G1470. Diquat on Potatoes. Evaluation of the Analytical Method and Residue Data.
Manufacturing process information on page 3 is not included.
Document (PDF) (479 KB PDF).

March 06, 1975. Review. 16 Page(s).
Ronald Ney. Efficacy & Ecological Effects Branch.
Environmental Chemistry Evaluation for Diquat Dibromide (6,7-dihydrodipyrido(1,2-2: 2',1'-C)
pyrazinedium dibromide). PP No. 1F1101. Reg. File No. 239-1663.
Document (PDF) (704 KB PDF).

September 10, 1975. Review. 6 Page(s).
Ronald Ney. Efficacy & Ecological Effects Branch.
Reg. No. 239-1663. Ortho Diquat Water Weed Killer.
Revision in Labeling, Expansion of Use and Change in Use Directions.
Document (PDF) (225 KB PDF).

September 18, 1975. Review. 4 Page(s).
Ronald Ney. Efficacy & Ecological Effects Branch.
Petition No. 5E1648. Food Additive Petition.
Document (PDF) (149 KB PDF).

September 19, 1975. Review. 2 Page(s).
Ronald Ney. Efficacy & Ecological Effects Branch.
File No. 10583-0. Control Rapid Kill #1. Registration.
Document (PDF) (77 KB PDF).

August 08, 1978. Memorandum. 1 Page(s).
R. J. Hummel. Residue Chemistry Branch.
Ethylene Dibromide (EDB) as an Impurity in Diquat Formulations.
Document (PDF) (59 KB PDF).

November 28, 1978. Review. 3 Page(s).
C. W. Collier. Environmental Fate Branch.
Reg. No. 239-1663. Ortho Diquat Aquatic Weed Killer.
Label Change to Include Additional Water Sources.
Document (PDF) (89 KB PDF).

May 28, 1980. Review. 4 Page(s).
John Harris. Environmental Fate Branch.
Reg. No. 239-2247, 9F2265. Diquat 2 Spray. Scientific Review - Potato Use.
Document (PDF) (157 KB PDF).

October 09, 1980. Memorandum. 3 Page(s).
R. B. Perfetti. Residue Chemistry Branch.
PP #5E1648 and FAP #5H5097. Diquat in Water, Irrigated Crops and Fish.
Amendment of 8/19/80.
Document (PDF) (179 KB PDF).

March 05, 1981. Review. 8 Page(s).
Willa Garner. Environmental Fate Branch.
Reg. No. 239-1663. Ortho Diquat. Review of Environmental Chemistry Data.
Document (PDF) (340 KB PDF).

March 23, 1981. Memorandum. 10 Page(s).
Krystyna Locke. Toxicology Branch.
Request for Tolerance for Pesticide Diquat in or on Potatoes and Other
Products, Resulting From the Preharvest Use of Diquat 2 Spray on Potato Vines.
Reg. Nos. 239-2247 and 239-1663. Inert ingredient information on page 3 not included.
Document (PDF) (1275 KB PDF).

May 24, 1983
Memo to File. 1 Page(s).
Larry Schnaubelt. Fungicide-Herbicide Branch.
Re: Proposal to Delete the Swimming Restriction
from the Ortho Diquat Water Weed Killer Labeling.
Document (PDF) (44 KB PDF).

June 02, 1983. Memorandum. 3 Page(s).
Richard Loranger. Residue Chemistry Branch.
EPA No. 239-ELNL. Request for Registration of Diquat Concentrate.
Commercial/financial information on page 1 is not included.
Page 2 is not included - inert ingredient and manufacturing process information.
Document (PDF) (99 KB PDF).

March 07, 1984. Review. 3 Page(s).
Samuel Creeger. Exposure Assessment Branch.
File No. 239-ELNL. Ortho Diquat Concentrate. Assess Exposure to EDB Impurity.
Document (PDF) (124 KB PDF).

April 04, 1984. Review. 3 Page(s).
Samuel Creeger. Exposure Assessment Branch.
File No. 239-ELNL. Ortho Diquat Concentrate.
Assess Exposure to EDB Impurity in Reformulated Product with Reduced EDB Content.
Document (PDF) (125 KB PDF).

August 10, 1984. Memorandum. 4 Page(s).
Bruce Molholt. CERCLA Enforcement, EPA Region III
Mutagenicity of Diquat.
Document (PDF) (280 KB PDF).

September 18, 1984. Memorandum. 1 Page(s).
Bruce Molholt. CERCLA Enforcement, EPA Region III
Mutagenicity of Diquat.
Document (PDF) (61 KB PDF).

October 07, 1984. Memorandum. 1 Page(s).
Stephen Wassersug. Hazardous Waste Mgmt Div, EPA Region III
Mutagenicity of Diquat.
Document (PDF) (41 KB PDF).

December 12, 1984. Memorandum. 4 Page(s).
Krystyna Locke. Toxicology Branch.
Diquat: Correspondence from Region III (EPA) Regarding the Teratogenicity and Mutagenicity
of Diquat, and the Reinstatement of the 14-Day Ban on Swimming in Diquat- Treated Water.
Document (PDF) (246 KB PDF).

December 31, 1985
Final Report. 35 Page(s).
Dynamac Corporation.
Diquat Dibromide - Task 1: Review and Evaluation of Individual Studies.
Document (PDF) (1175 KB PDF).

January 09, 1986
Final Report. 8 Page(s).
Dynamac Corporation.
Diquat Dibromide - Task 2: Environmental Fate and Exposure Assessment.
Document (PDF) (348 KB PDF).

December 10, 1986. Memorandum. 11 Page(s).
Krystyna Locke. Toxicology Branch.
Evaluation of Five Acute Toxicity Studies with Formulations, Diquat Water Weed
Killer or Diquat 2 Spray. Tox Review 005619.
Document (PDF) (444 KB PDF).

February 02, 1987. Memorandum. 3 Page(s).
J. Garbus. Residue Chemistry Branch.
EPA No. 239-1663: Diquat Dibromide. Additional Data for Amended Registration
for Aquatic Use on Hydrilla. MRID No. 400082-01; RCB No. 1725.
Document (PDF) (202 KB PDF).

May 18, 1987. Review. 4 Page(s).
Emil Regelman. Exposure Assessment Branch.
Reg. No. 239-1663. Diquat Water Weed Killer. Review Request for Modification
of the Leaching Study for the Diquat Registration Standard.
Document (PDF) (186 KB PDF).

December 08, 1987. Review. 3 Page(s).
Michael Firestone. Exposure Assessment Branch.
File #202,665. Diquat. Exposure Assessment.
Document (PDF) (227 KB PDF).

December 17, 1987. Review. 5 Page(s).
Frank Davido. Exposure Assessment Branch.
Reg. No. 239-2505. Ortho Diquat Concentrate. Registration: Permeability of Protective
Gloves; Spray Drift; and Droplet Spectrum.
Document (PDF) (228 KB PDF).

December 17, 1987. Review. 6 Page(s).
Therese Dougherty. Exposure Assessment Branch.
Reg. No. 239-2505. Diquat Dibromide. Responses to Registration Standard:
Glove Permeability, Spray Drift and Questions on the Soil Dissipation Study Sampling Scheme.
Document (PDF) (462 KB PDF).

February 16, 1988. Memorandum. 5 Page(s).
Mary Waller. Fungicide Herbicide Branch.
EPA File Symbol 192-RTI Dexol Weed & Grass Killer Concentrate Acute studies.
MRID No. 403599-02 through -07.
Document (PDF) (306 KB PDF).

April 12, 1988. Memorandum. 6 Page(s).
Linda Propst. Residue Chemistry Branch.
EPA Reg. No. 239-2505. Residues of diquat in Fish and Shellfish.
MRID No. 46427601. RCB No. 3508.
Document (PDF) (269 KB PDF).

August 05, 1988. Memorandum. 3 Page(s).
Krystyna Locke. Toxicology Branch.
Diquat: Evaluation of Studies Submitted by Chevron Chemical Company Under the
Registration Standard Requirements. EPA ID No. 239-2505 (Ortho Diquat Concentrate).
Tox Review 006719.
Document (PDF) (165 KB PDF).

February 21, 1989. Review. 27 Page(s).
Paul Mastradone. Environmental Fate & Ground Water Branch.
Reg. No. 239-1663. Diquat Water Weed Killer. Remove Reentry Label Restriction
Prohibiting Swimming in Treated Areas Within 14 Days after Treatment.
Page 27 is not included - product ingredient source and quality control information, and product chemistry data.
Document (PDF) (1254 KB PDF).

March 23, 1989. Memorandum. 4 Page(s).
Curt Lunchick. Science Analysis & Coordination Branch.
Diquat Swimming Restriction.
Document (PDF) (227 KB PDF).

April 07, 1989. Memorandum. 2 Page(s).
Krystyna Locke. Toxicology Branch.
EPA Reg. No. 239-1663-AA. Diquat Water Weed Killer: Swimming Restriction.
MRID No. 409276-02.
Document (PDF) (114 KB PDF).

March 02, 1992. Memorandum. 38 Pages.
Tim Leighton. Antimicrobials Division
Diquat - Draft Report. Review and Evaluation of Worker Exposure Studies
and Individual Foliar Dislodgeable and Soil Residue Dissipation Studies.
MRID Nos. 409174-01, 02; 413772-00, 02, 03; and 413741-00).
Pages 33-38 removed, copyrighted material.
Document (PDF) (927 KB PDF).

September 01, 1994. Memorandum. 22 Page(s).
Anthony Maciorowski. Ecological Effects Branch.
Diquat Dibromide Reregistration Science Chapter (D198588).
Document (PDF) (1936 KB PDF).

September 29, 1994. Memorandum. 29 Page(s).
William Schneider. Science Analysis & Coordination Branch.
Transmittal of EFED List A Summary for Diquat dibromide (Chemical # 032201) Case # 0288.
Document (PDF) (1947 KB PDF).

September 29, 1994. Memorandum. 9 Page(s).
William Schneider. Science Analysis & Coordination Branch.
EFED Recomendations and Mitigation Measures for Diquat dibromide (Chemical # 032201) Case # 0288.
Document (PDF) (683 KB PDF).

August 22, 2001. Memorandum. 23 Pages.
Tom Brennan. Reregistration Branch 4.
HEDís Review of Diquat: Worker Exposure During Mixing, Loading, and Application of Reglon with Knapsack Sprayers;
(MRID# 44493001; PC code 032201; DP Barcode D222970).
Document (PDF) (80 KB PDF).
Attachment(s) Following:

June 29, 2001. Review.
Marit Espevik/Nate Mottl.
Attachment 1. Versar, Inc. Review Memo Dated June 29, 2001.
Mixer/loader/applicator passive dosimetry and biological monitoring study.

*End of Attachments*

March 25, 2002. Memorandum. 44 Page(s).
Becky Daiss. Reregistration Branch 4 HED.
Diquat Dibromide HED Risk Assessment for Tolerance Reassement Eligibility Document (TRED).
Document (PDF) (3846 KB PDF).

Publications | Glossary | A-Z Index | Jobs


Local Navigation


Jump to main content.