CAS No. 145701-23-1

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Adverse Effects

ACTIVITY: Herbicide (Triazolopyrimidine )

Chemical Name: N-(2,6-difluorophenyl)-8-fluoro-5 methoxy [1,2,4] triazolo [1,5-c] pyrimidine-2-sulfonamide


Adverse Effects:

Body Weight Decrease
Endocrine: Adrenal

Environmental Effects:

European Commission: .... particular attention to the potential for groundwater contamination, when the active substance is applied in regions with vulnerable soil and/or climatic conditions.

Regulatory Information
(only comprehensive for the US)
US EPA Registered: YES. First-time approval, September 28, 2007
Registered use in
(includes only a limited list of countries)

Belgium, Canada, Finland, Germany, Hungary, South Africa, Tanzania
Other Information
Molecular Formula: C12H8 F3 N5O3S 
Entry Year: 1998  
Manufacturers: Dow AgroSciences 
Other Names: Boxer
Of special interest:
PAN Data 
June 6, 2005 - CANADA - Regulatory Decision Document RDD2005-03. Florasulam EF-1343 Suspension Concentrate Herbicide... the active ingredient florasulam and associated end-use product EF-1343 Suspension Concentrate Herbicide for the control of broadleaf weeds in spring wheat, including durum, spring barley and oats (tank-mix only) are elibible for full registration under the Pest Control Products Regulations. EF-1343 is manufactured by Dow AgroSciences Canada Inc.
October 6, 2004 - CANADA: Proposed Regulatory Decision Document PRDD2004-4. The technical grade active ingredient florasulam associated end-use product EF-1343 Suspension Concentrate Herbicide for the control of broadleaf weeds in spring wheat, including durum, spring barley and oats (tank-mix only) are eligible for full registration under Section 13 of the Pest Control Products (PCP) Regulations. These products were granted temporary registration as per Regulatory Note REG2001-12 (see Sept 27, 2001, report below). This Proposed Regulatory Decision Document (PRDD) provides a summary of the data reviewed and the rationale for the proposed regulatory decision. The Canadian Pest Management Regulatory Agency (PMRA) will accept written comments on the proposal up to 45 days from the date of publication of this document. EF-1343 Suspension Concentrate Herbicide "is to be used only in the prarie provinces and the Peace River region of British Columbia, which are the major cereal production areas of Canada (page 4)."
September 18, 2002 - Review report for the active substance florasulam. European Commission Health & Consumer Protection Directorate-General.  
September 27, 2001 - Opinion of the European Commission Scientific Committee on Plants on specific questions from the Commission concerning the evaluation of Florasulam (EF-1343] in the context of Council Directive 91/414/EEC. (SCP/FLORAS/002-Final 29 October 2001. Opinion adopted by the Committee on 27 September 2001)
September 21, 2001 - Florasulam EF-1343 Suspension Concentrate Herbicide. REF2001-12. .Canadian Pest Management Regulatory Agency (PMRA). Health Canada.
April 2002 - Beer in the UK: 23 organofluorine pesticides approved for use on malting barley.
Published by the British Beer and Pubs Association and Brewing Research International.
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 Floransulam 

US Federal Register
Date Published Docket Identification Number Details
September 28, 2007 EPA-HQ-OPP-2006-0993

Dow AgroSciences. Pesticide Tolerance. FINAL RULE. FIRST-TIME APPROVAL FOR THE USE OF FLORASULAM, a selective triazolopyrimidine sulfonanilide post-emergent herbicide, in or on the following food commodities.:

at 0.01 ppm: Barley, grain; Oat, grain; Rye, grain; Wheat, grain
at 0.05 ppm: Barley, hay; Barley, straw ; Oat, forage ; Oat, hay ; Oat, straw ; Rye, forage ; Rye, straw; Wheat, forage; Wheat, hay; Wheat, straw

The mode of action for florasulam is through inhibition of the plant enzyme acetolactate synthase (ALS). The inhibition of ALS results in retardation of plant growth processes leading to death of the plant. Florasulam was first registered in Israel in 1998.

Florasulam: Human Health Risk Assessment for Proposed Use on Cereal Grains. May 31, 2007.

-- Developmental Toxicity Studies. In the rat developmental toxicity study, at 750 mg/kg/day, body weights were decreased by 4-6 during GD 6-19, resulting in a 16% decrease in body weight gains during treatment (GD 6-16); food consumption was also decreased (not statistically analyzed) by 6-13% during the treatment period. Additionally at this dose, absolute and relative (to body weight) kidney weights were increased (p<=0.05) by 8 and 12%, respectively. At ≥250 mg/kg/day, slight decreases (3-4%) were observed in fetal body weight, accompanied by delayed ossification (not significant) of the skull, ribs, and sternebrae at 750mg/kg/day. However, both findings were within the historical control range.

ENDPOINTS OF CONCERN in human health risk assessment:
• Acute dietary (Females 13-49 years of age): No appropriate endpoint identified.
• Acute dietary( General population including infants and children): No appropriate endpoint identified.
• Chronic dietary (All populations): Chronic toxicity - dogs. LOAEL = 50 mg/kg/day, based on decreased body weights (17%), decreased body weight gains (68%), and food consumption in the females; adverse liver alterations; slight vacuolation of the zona reticularis and zona fasciculate in the adrenal gland (fatty change) in both sexes.
• Short-term dermal (1 to 30 days) (Residential): No appropriate endpoint identified.
• Inhalation Short-term (1-30 days): 90-day oral toxicity - dogs. LOAEL = 50 mg/kg/day based on increased incidence/severity of hepatic vacuolation in both sexes.

EPA is not establishing the proposed tolerances, as requested by Dow AgroSciences, for barley, forage and rye, hay because EPA does not consider these items to be significant food commodities as noted in Table 1 of the OPPTS 860 guidelines. EPA is also not establishing the proposed tolerances for triticale. Triticale is covered by the tolerance for wheat as specified in 40 CFR 180.1(g).

The 5-OH degradate formed by demethylation of florasulam is by far the predominant environmental residue reaching maximum levels of 70% of applied material in the hydrolysis and metabolism (soil, aquatic) studies. This degradate is assumed to be of comparable toxicity to the parent. On this basis, the residues of concern in drinking water are the parent and 5-OH degradate.

In aquatic systems, florasulam degrades with half-lives of 3-18 days in aerobic systems and half- lives of 2-13 days in anaerobic systems. In aerobic aquatic systems, florasulam is biotransformed to 5-OH-XDE-570, which is then further biotransformed to DFP-ASTCA and STCA (tentative identification). However, 5-OH-XDE-570 degrades much more slowly than the parent, degrading with a half-life of 169 days in one aerobic system and remaining stable in another aerobic system. In anaerobic aquatic systems, 5-OH-XDE-570 is stable. Thus, 5-OH-XDE-570 is expected to be persistent in both aerobic and anaerobic aquatic systems... both florasulam and 5-OH-XDE-570 are very mobile in soil and, thus, have the potential to leach - the potential to leach will be greater when there is excessive rainfall or irrigation. (Page 24 of the Human Health Risk Assessment)

January 24, 2007 EPA-HQ-OPP-2006-0993 Dow AgroSciences. Pesticide petition: PP 6F7061.
Proposal to establish a tolerance for residues in or on the food commodities
-- wheat at 0.01 ppm
-- barley at 0.01 ppm
-- oat at 0.01 ppm
-- rye at 0.01 ppm
-- triticale (grain) at 0.01 ppm
(no explanation for the following)
-- wheat at 0.05 ppm
-- barley at 0.05 ppm.
-- oat at 0.05 ppm.
-- rye at 0.05 ppm
-- triticale (forage, hay, and straw) at 0.05 ppm.
December 27, 2006 EPA-HQ-OPP-2006-0992

Dow AgroSciences. Registration applications for pesticide products containing new active ingredients not included in any previously registered products.

Product name: GF-1727. Proposal classification/Use: Wheat (including durum), barley, oats, rye, and triticale.

Product name: GF-184 (contains Florasulam + Fluroxypyr 1-methylheptyl ester). Proposal classification/Use: Wheat (including durum), barley, oats, rye, and triticale.

Product name: EF-1343. Proposal classification/Use: Wheat (including durum), barley, oats, rye, and triticale.

Product name: EF-1440. Proposal classification/Use: Manufacturing use only.

Product name: EF-1383 (contains Florasulam + 2,4-D). Proposal classification/Use: Wheat (including durum), barley, rye, and triticale.

Product name: Florasulam Wet Cake Technical. Proposal classification/Use: Manufacturing use only.



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