Diflubenzuron
CAS No. 35367-38-5

 
 

Return to
Adverse Effects

Abstracts

ACTIVITY: Insecticide, Acaricide, Chemosterilant (Benzoylurea)

CAS Name: N-[[(4-chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide

Structure::

Adverse Effects:

Endocrine: Suspected Disruptor
Endocrine: Testicular

Effects attributed to PCA (4-Chloroaniline) a metabolite of diflubenzuron:
Bone
Blood
Cancer: Spleen, Liver due to metabolite 4-chloroaniline
Endocrine: Adrenal
Liver
Spleen

NOTE: Chloroaniline, p (or 4-chloroaniline) is a metabolite of Diflubenzuron. In 2006, USEPA classified chloroaniline, p as a "Group B2 -- Probable Human Carcinogen." "Spleen (fibrosarcomas, hemangiosarcomas & osteosarcomas) (M); Adrenal (pheochromocytomas (M & F); F344/N rats. Hepatocellular adenomas/carcinomas (M); Hemangiosarcomas in spleen and/or liver (M) in B6C3F1 mice."
Ref:
April 26, 2006 . Chemicals Evaluated for Carcinogenic Potential by the Office of Pesticide Programs. From: Jess Rowland, Chief Science Information Management Branch Health Effect Division (7509C) Office of Pesticide Programs, USEPA.

Environmental Effects:

Acute aquatic toxicity

Regulatory Information
(only comprehensive for the US)
US EPA Registered: Yes 
US EPA PC Code: 108201
212200
 
California Chemical Code 1992 
US Tolerances: CFR 180.377
CFR 186.2000
 
FDA LMS Code: 651 
US EPA Permit Date
and Registrant:
1976,
Thompson-Haywood
 
Registered use in
(includes only a limited list of countries)

Australia, Canada, Denmark, Finland, Hungary, India, Japan, Netherlands, New Zealand, Portugal, UK, US
Africa: Burkina Faso, Cape Verde, Chad, Gambia, Gunina-Bissau, Madagascar, Mali, Mauritania, Niger, Senegal, South Africa, Tanzania
 
Japan's Maximum Residue Levels (MRLs) Apple, Artichoke, Barley, Brussel Sprouts, Button mushrooms, Cabbage, Cotton Seeds, Cucumber, Ginger, Grapefruit, Japanese Plum (inc prunes), Lemon, Lime, Melons, Onion, Orange, Peach, Pear, Persimon, Soybeans, Tea, Tomato, Walnut, Watermelon, Wheat
--
Note very high level - 20 ppm - for Tea (Green, Black, Oolong, Wulung) 
US Maximum Residue Levels permitted in food commodities  
Permitted in or on over 400 food commodities, including:
Artichoke, Egg, Grapefruit, Pasture rangeland), Milk, Mushroom, Pear, Rice, Soybean, Tangerine, Walnut, Cattle, Goat, Horse, Hog, Poultry, Sheep
 
Other Information
Molecular Formula: C14H9Cl F2 N2O2  
Inventing Company: First commercialized by.:
Philips-Duphar BV,
The Netherlands
(Solvay Duphar BV)
 
Manufacturers: Durphar BV,
UNIROYAL
 
Other Names: Adept
DFB
Difluron
Dimilin
DU 112307
400-EUP-69
Fleececare
Magnum
PH 60-40
Strike
TH 6040 
Manufacture sites:

CHINA:
Shijiazhuang Chemical
Factory, Hebei Province

HOLLAND:
Uniroyal, Amsterdam

INDIA:
Gharda Chemicals,
Maharashra

Of special interest:
PAN Data 
Material Safety Data Sheets & Labels
Jan 23, 2006: Conservation Group Moves for Court Order Restricting Use of 66 Pesticides in Core Red-Legged Frog Habitat.
San Francisco, Calif. – The Center for Biological Diversity (CBD) in a legal motion today asked a U.S. District Court to protect the threatened California red-legged frog (Rana aurora draytonii) from 66 of the most toxic and persistent pesticides authorized for use in California, by creating pesticide-free buffer zones around the frog’s core habitat and by requiring consumer hazard warnings so that all Californians may learn how to protect frogs. [Trifluralin was one of the 66 pesticides.]
In response to a lawsuit filed by CBD against the U.S. Environmental Protection Agency (EPA) in April of 2002, the District Court found in September of 2005 that the EPA violated the Endangered Species Act (ESA) by registering pesticides for use without considering how they might impact the continued existence of the red-legged frog. The motion for “injunctive relief” delivered today asks the court to protect the frog from pesticides in or adjacent to aquatic frog habitat designated as core recovery areas, until the EPA completes a formal consultation with the U.S. Fish and Wildlife Service (USFWS) on the impacts of the pesticides on red-legged frogs, as required under the ESA... CBD is asking the Court to impose a three-year schedule for the EPA to determine whether the 66 pesticides may affect the red-legged frog and to complete formal consultations with USFWS to ensure the pesticides are not jeopardizing the frog or contributing to its decline. To minimize harm to frogs during the consultation process, the motion asks for an injunction on use of the pesticides around aquatic features and upland habitats within the frog’s core recovery areas, as designated by USFWS in the agency’s Recovery Plan for the California Red-legged Frog. This injunction would also apply buffer areas for terrestrial and aerial pesticide applications, affecting approximately 7 percent of the current range of the frog and less than 1 percent of the area of California. CBD is also requesting that the EPA conduct monitoring for pesticides in three of the recovery areas to determine whether the buffers are effectively protecting the frog, inform pesticide users about the injunction, and post point-of-sale notifications warning consumers about harmful effects these pesticides may have on the frog...

August 2004 - Canada: Re-evaluation of Diflubenzuron. Proposed Acceptability for Continuing Registration. No. PACR2004-35. Pest Management Regulatory Agency.

--The following statements must be added to the "Precautions" section of the label:

• Do not use in residential areas. Residential areas are defined as sites where bystanders including children may be potentially exposed during or after spraying. This includes around homes, on school grounds, in parks, playgrounds, playing fields, around public buildings or any other areas where the general public including children could be exposed."

-- A section entitled "Environmental Hazards" must be added to the label and include the following statements:

• TOXIC TO AQUATIC ORGANISMS. DO NOT contaminate irrigation / drinking water supplies or aquatic habitats by cleaning of equipment or disposal of wastes.

• For gypsy moth control, observe buffer zones specified under Directions for Use.

-- The registrant is required to replace the statement:

• FOREST INSECT CONTROL: For use only by Plant Protection Division, Agriculture, Canda

with the following:

FOREST INSECT CONTROL: For use only by the Canadian Food Inspection Agency

Products containing DFB registered in Canada as of 31 March 2004:
Dimlin 25% WP Insecticide. Registrant: Crompton Co. Reg. No.: 13816
Diflubenuron Technical Insecticide. Registrant: Crompton Co. Reg. No. 25451

August 1997 - US EPA Reregistration Eligibility Decision (RED)
January 28, 1999 - US EPA Fact Sheet (pdf) 
1998 - 1999 - Levels of residues on Australian wool 
US Map of pesticide use based on 1991-1995 data
Insecticide products - partial list
2002 - Review and synthesis of the environmental impacts of aquaculture. The Scottish Association for Marine Science and Napier University. Scottish Executive Central Research Unit.
1998 - US EPA places Diflubenzuron in the category of a "Reduced-Risk Pesticide"  
1996 - Environmental Health Criteria Report 184. WHO International Programme on Chemical Safety. 
Pesticide Information Profile - Cornell Management Education Program 
Abstracts 
October 1998 - Structural Pest Management pesticides. FAN's compilation of information cited on fluorine and organofluorine pesticides published in General Pest Management, Category 7A. A Guide for Commercial Applicators. Prepared by: Carolyn Randall, MSU Pesticide Education Program. Published by MSU Pesticide Education (Michigan State University). MSU manual number: E-2048.
Chemical Profile - Environmental Defense Fund Scorecard
List of Brand Name Pesticides which use Diflubenzuron - Environmental Defense Fund Scorecard
December 10, 2001 - Australia: "Current List. RECORD OF APPROVED ACTIVE CONSTITUENTS FOR CHEMICAL PRODUCTS."
August, 2001 - IR-4 - New Products/Transitional Solution List - This list contains brief descriptions of numerous new pest control materials that have been introduced over the last several years. Additionally, it contains information on some "older" crop protection chemicals that are believed to have room for new uses. This List includes Diflubenzuron

Rationale for US EPA to add Diflubenzuron to the Toxic Release Inventory

In a 2-year study in which beagle dogs received diflubenzuron daily in gelatin capsules, the LOAEL for increases in sulfhemoglobin and methemoglobin was 10 mg/kg/day and the NOAEL was 2 mg/kg/day. EPA has derived an oral RfD of 0.02 mg/kg/day for this chemical from this study. Similar effects were noted in two separate 2-year rat feeding studies (the LOAEL was 7.8 to 8 mg/kg/day; the NOAEL was 2 mg/kg/day), and in a lifetime oral study in mice (the LOAEL was 12 mg/kg/day; the NOAEL was 2.4 mg/kg/day). EPA believes that there is sufficient evidence for listing diflubenzuron on EPCRA section 313 pursuant to EPCRA section 313(d)(2)(B) based on the available hematological toxicity data. Measured aquatic acute toxicity data for diflubenzuron include a 48-hour LC 50 of 4.55 ppb for daphnids. EPA believes that there is sufficient evidence for listing diflubenzuron on EPCRA section 313 pursuant to EPCRA section 313(d)(2)(C) based on the environmental toxicity data for this chemical.

Ref: USEPA/OPPT. Support Document for the Health and Ecological Toxicity Review of TRI Expansion Chemicals. U. S. Environmental Protection Agency, Washington, DC (1993). As cited by US EPA in: Federal Register: January 12, 1994. Part IV. 40 CFR Part 372. Addition of Certain Chemicals; Toxic Chemical Release Reporting; Community Right-to-Know; Proposed Rule.


June 14, 2001 - Implementation of the Community Strategy for Endocrine Disruptors - a range of substances suspected of interfering with the hormone systems of humans and wildlife. Communication from the Commission to the Council and the European Parliament. Commission of the European Communities, Brussels COM (2001) 262 final. (More information available at: http://europa.eu.int/comm/environment/docum/01262_en.htm )

This document presents a "priority list of substances for further evaluation of their role in endocrine disruption. During 2000, a candidate list of 553 man-made substances and 9 synthetic/natural hormones has been identified." Organofluorine pesticides in this list include:

Substances included on the Endocrine Disruptor Liist CAS No. Substances included on the Endocrine Disruptor Liist CAS No.
Bifenthrin 82657-04-3 Flutriafol 76674-21-0
Cyhalothrin (@Karate) 91465-08-6 Fluvalinate 69409-94-5
Diflubenzuron 35367-38-5 Prodiamine 29091-21-2
Epoxiconazole - Stannane, tributylfluoro [Tributyltin fluoride] 1983-10-4
Fipronil - Thiazopyr -
Fluazifop-butyl 69806-50-4 Trifluralin -

October 2002 - Factsheet. Guidelines for producing European eco-label and nil residue wool. Western Australia Department of Agriculture. Also available at http://www.agric.wa.gov.au/agency/pubns/factsheets/2001/fs02801.pdf
No diflubenzuron or triflumuron to be used, as residue levels are likely to exceed limits.
Eco-label wool does not mean nil residue wool and the current limits for pesticide levels can be achieved fairly easily using standard production systems. The pesticide limits for greasy wool are:
Total synthetic pyrethroids (SP) less than 0.5 mg/kg
Total organophosphates (OP) less than 2 mg/kg
Total insect growth regulators (IGR)* less than 2 mg/kg
*IGRs cover diflubenzuron (e.g. Magnum, Strike, Fleececare etc.) and triflumuron (e.g. Zapp, etc.). Use of either of these chemicals is likely to exceed this level, e.g. expected residues from using triflumuron (e.g. Zapp etc.) off-shears is 2530 mg/kg...

Average pesticide residues in Australian fleece wool
Ref: Sheep. Low-cost residue test will keep wool clean.
Page 63. FARMING AHEAD No. 109 - January 2001

- Organo-
phosphates
Synthetic
pyrethroids
Cyromazine Dicyclanil Diflubenzuron Triflumuron
1992-93
10.2
5.8
-
-
-
-
1993-94
9.0
6.6
-
-
-
-
1994-95
4.3
5.7
5.2
-
-
-
1995-96
4.4
5.5
6.3
-
-
-
1996-97
4.5
3.8
8.7
-
1.2
3.5
1997-98
5.8
3.3
5.8
-
3.6
6.1
1998-99
2.4
1.6
7.4
-
3.5
7.6
1999-00
2.2
2.0
5.1
0.1
2.9
9.0
Source: Woolmark Company

US Federal Register

•• Note: Due to length, not all entries are listed below. Click here to view all.

Date Published Docket Identification Number Details
July 25, 2007 EPA-HQ-OPP-2007-0446

Pesticide tolerance. FINAL RULE. EPA, on its own initiative, establishes a time-limited tolerance for diflubenzuron and its metabolites p-chlorophenylurea and p- chloroaniline in or on lemon at 0.8 ppm. This action is in response to EPA's granting of an emergency exemption under section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act authorizing use of the pesticide on lemon. This regulation establishes a maximum permissible level for combined residues of diflubenzuron and its metabolites p-chlorophenylurea and p-chloroaniline, in this food commodity expressed in terms of the combined residues of diflubenzuron and its metabolites CPU and PCA. The tolerance expires and is revoked on December 31, 2010.

Document available with this final rule: Diflubenzuron. Human Health Risk Assessment for the Proposed Establishment of an Emergency Exemption Tolerance for Use in/on Lemons. April 16, 2007. Docket ID: EPA-HQ-OPP-2007-0446-0002. Excerpt:

(page 6): In subchronic and chronic feeding studies, the primary endpoint of concern, produced most likely by PCA, was methemoglobinemia and/or sulfhemoglobinemia. These effects were evident in both sexes of mice, rats, and dogs and were produced by more than one route of administration in rats [i.e., oral, dermal and inhalation]. The general consequence of methemoglobinemia and/or sulfhemoglobinemia is the impairment of the oxygen transportation capacity of the blood, which is generally known to be caused by aromatic amines in both humans and animals.

Cancer. The Agency has classified diflubenzuron as ``Group E,'' evidence of non-carcinogenicity for humans, based on lack of evidence of carcinogenicity in rats and mice. There are also two metabolites of diflubenzuron; PCA and CPU. PCA tested positive for splenic tumors in male rats and hepatocellular adenomas/carcinomas in male mice in a National Toxicology Program (NTP) study. Therefore, EPA classified PCA as a ``Group B2'' probable human carcinogen. The Agency determined for those commodities that contained PCA and CPU, the Q1* of PCA should be used to calculate the cancer risk from the sum of these two metabolites.
Based on the submitted metabolism studies, there are two possible sources for dietary exposure to PCA and CPU: Residues in mushrooms and residues in milk and liver. Because human exposure to PCA and CPU will not be affected by the proposed new uses, and EPA has previously concluded that exposure to these compounds is safe, therefore, the cancer dietary risk from PCA and CPU will not be addressed in this document. For a detailed discussion on the exposure and risks to PCA and CPU, please refer to the September, 2002 Federal Register document titled Diflubenzuron; Pesticide Tolerances (September 19, 2002, FR 67 59006).

November 29, 2006 EPA-HQ-OPP-2006-0181

IR-4. Pesticide tolerance. FINAL RULE.
Tolerances are established for combined residues of diflubenzuron, (N-[[(4-chlorophenyl)amino]carbonyl]-2,6-
difluorobenzamide and its metabolites 4-chlorophenylurea and 4-chloroaniline in or on the raw agricultural commodities

Barley, grain at 0.06 ppm
Barley, hay at 3.0 ppm
Barley, straw at 1.8 ppm

Brassica, leafy greens, subgroup 5B at 9.0 ppm

This subgroup includes 10 commodities: broccoli • broccoli, cavalo • broccoli, chinese • brussels sprout • cabbage • cabbage, chinese mustard • cabbage, chinese napa • cauliflower • cavalo broccolo • kohlrabi

Grain, aspirated fractions at 11 ppm
Oat, forage at 7.0 ppm
Oat, grain at 0.06 ppm
Oat, hay at 6.0 ppm
Oat, straw at 3.5 ppm
Peanut at 0.10 ppm
Peanut, hay at 55 ppm
Peanut, refined oil at 0.20 ppm
Pummelo at 0.50 ppm
Turnip greens at 9.0 ppm
Wheat, forage at 7.0 ppm
Wheat, grain at 0.06 ppm
Wheat, hay at 6.0 ppm
Wheat, straw at 3.5 ppm

September 1, 2006 EPA-HQ-OPP-2006-0702

Request for Public Comment on Proposed Stipulated Injunction Involving 66 Pesticides and the California Red-legged Frog.
Center for Biological Diversity
vs
EPA

April 12, 2006 EPA-HQ-OPP-2006-0181

IR-4. Pesticide petitions: 5E6965, 5E6966, and 5E6967.
Diflubenzuron and metabolites convertible to p-chloroaniline.

PP 5E6965
proposes to establish tolerances for
-- barley, grain; oat, grain; and wheat, grain at 0.06 ppm
-- barley, forage; oat, forage; and wheat, forage at 5.0 ppm
-- barley, hay; oat, hay; and wheat, hay at 2.0 ppm
-- barley, straw; oat, straw; and wheat, straw at 2.0 ppm
-- barley, aspirated barley fractions at 3.0 ppm
-- oat, aspirated oat fractions at 3.0 ppm
-- wheat, aspirated wheat fractions at 3.0 ppm
-- pummelo at 0.5 ppm.

PP 5E6966 proposes to establish tolerances for
-- brassica, leafy greens subgroup 5B; turnip at 8.0 ppm

This subgroup includes 8 commodities.
broccoli raab • cabbage, chinese bok choy • collards • kale • mizuna • mustard greens • mustard spinach • rape greens

-- eggplant at 1.0 ppm
-- okra at 1.0 ppm.

PP 5E6967 proposes to establish a tolerance for
-- peanut at 0.2 ppm.

Dec 21, 2005 EPA-HQ-OPP-2005-0292

Extension of Tolerances for Emergency Exemptions. FINAL RULE.

EPA has authorized under FIFRA section 18 the use of diflubenzuron on wheat and barley for control of grasshoppers in Montana, Washington, and Idaho. This regulation extends time-limited tolerances for combined residues of the insecticide diflubenzuron and its metabolites 4-chlorophenlyurea and 4-chloroaniline (CPU) and (PCA) in or on wheat and barley grain at 0.05 ppm, wheat and barley straw at 0.50 ppm, wheat and barley hay at 1.0 ppm, wheat milled byproducts at 0.10 ppm, and aspirated grain fractions at 30 ppm for an additional 3-year period. These tolerances will expire and are revoked on December 31, 2008. Time-limited tolerances were originally published in the Federal Register of August 27, 2003.

Nov 16, 2005 OPP-2005-0277 Pesticide Emergency Exemptions.
• Idaho.
Specific: EPA authorized the use of diflubenzuron on barley and wheat to control grasshoppers and Mormon crickets; July 1, 2005 to August 1,
2005.
• Montana. EPA authorized the use of diflubenzuron on alfalfa to control grasshoppers and Mormon crickets; August 25, 2005 to September 30, 2005.
• Washington. Specific: EPA authorized the use of diflubenzuron on barley and wheat
to control grasshoppers and Mormon crickets; July 1, 2005 to August 1, 2005.
August 31, 2005 OPP-2005-0223

Pesticide Emergency Exemptions:

• Montana. EPA authorized the use of diflubenzuron on barley and wheat to control grasshoppers; June 22, 2005 to July 15, 2005. Contact: (Libby Pemberton).
• Nevada. EPA authorized the use of diflubenzuron on alfalfa to control Mormon cricket and grasshopper; June 3, 2005 to October 31, 2005. Contact: (Libby Pemberton).
• Utah. Specific: EPA authorized the use of diflubenzuron on alfalfa to control Mormon cricket and grasshopper; June 8, 2005 to October 31, 2005. Contact: (Libby Pemberton).
• Wyoming. Specific: EPA authorized the use of diflubenzuron on alfalfa to control Mormon cricket and grasshoppers; June 23, 2005 to October 31, 2005. Contact: (Libby Pemberton).

August 3, 2005 OPP-2005-0201

Cancellation of Pesticides for Non-payment of Year 2005 Registration Maintenance Fees.

Section 24(c) Registrations canceled for non-payment of the 2005
maintenance fee are shown in the following Table 1:

Table 1.--Section 24(c) Registrations Canceled for Non-Payment of Maintenance Fee

SLN no. Product Name
000400 OR-00-0021 Dimilin 2l
000400 OR-02-0009 Dimilin 2l
Dec 22, 2004 OPP-2004-0350 Pesticide Emergency Exemptions.
Idaho
-- Specific: EPA authorized the use of diflubenzuron on alfalfa to control Mormon crickets and grasshoppers; September 7, 2004 to October 31, 2004. Contact: (Libby Pemberton)
Montana
-- Specific: EPA authorized the use of diflubenzuron on alfalfa to control Mormon crickets and grasshoppers; September 7, 2004 to October 31, 2004. Contact: (Libby Pemberton)
Nov 10, 2004 OPP-2004-0232

Seven Pesticide Emergency Exemptions.
Idaho
--- Crisis: On May 3, 2004, for the use of diflubenzuron on alfalfa to control Mormon cricket and grasshoppers. This program is expected to end on October 31, 2004. Contact: (Libby Pemberton)
--- On June 8, 2004, for the use of diflubenzuron
on barley and wheat to control Mormon cricket and grasshoppers. This program ended on July 14, 2004. Contact: (Libby Pemberton)
Montana
--- Crisis: On May 20, 2004, for the use of diflubenzuron on alfalfa to control grasshoppers. This program is expected to end on September 30, 2004. Contact: (Libby Pemberton)
--- EPA authorized the use of diflubenzuron
on wheat and barley to control grasshoppers and Morom crickets; April 16, 2004 to July 15, 2004. Contact: (Barbara Madden)
Nevada - Specific: EPA authorized the use of diflubenzuron on alfalfa to control grasshoppers and Mormon crickets; April 16, 2004 to October 31, 2004. Contact: (Barbara Madden)
North Dakota - EPA authorized the use of diflubenzuron on wheat and barley to control various grasshopper species; June 30, 2004 to July 15, 2004. Contact: (Libby Pemberton)
Washington - Crisis: On June 3, 2004, for the use of diflubenzuron on barley and wheat to control Mormon cricket and grasshoppers. This program ended on July 14, 2004. Contact: (Libby Pemberton)

Oct 27, 2004 OPP-2004-0338 Cancellation of Pesticides for Non-payment of Year 2004 Registration Maintenance Fees.
Table 1.--Section 24(c) Registrations Canceled for Non-Payment of
Maintenance Fee
Name of Pesticide Product Name Registrant SLN No.
Diflubenzuron Dimilin 25 W for Cotton/Soybean Crompton Manufacturing Company, Inc. 000400 CA-94-0004
Diflubenzuron Dimilin 25W for Cotton/soybean Crompton Manufacturing Company, Inc. 000400 OR-88-0013

•• Note: Due to length, not all entries are listed above. Click here to view all.

 
Fluoride Action Network | Pesticide Project | 315-379-9200 | pesticides@fluoridealert.org