Full TGIF Record # 44622
Item 1 of 1
Web URL(s):http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1096-9063(199805)53:1<29::AID-PS749>3.0.CO;2-A/epdf
    Last checked: 10/07/2015
    Requires: PDF Reader
    Access conditions: Item is within a limited-access website
Publication Type:
i
Refereed
Author(s):Strek, Harry J.
Author Affiliation:DuPont Agricultural Products, Experimental Station, Wilmington, DE 19880-0402, USA
Title:Fate of chlorsulfuron in the environment: 1. Laboratory evaluations
Article Series:Fate of chlorsulfuron in the environment [1 of 2]
Section:Papers
Other records with the "Papers" Section
Source:Pesticide Science. Vol. 53, No. 1, May 1998, p. 29-51.
Publishing Information:London : Society of Chemical Industry
# of Pages:23
Keywords:TIC Keywords: Chlorsulfuron; Fate; Hydrolysis; Degradation; Photolysis; Leaching; Metabolites; Phytotoxicity
Abstract/Contents:"The behaviour and fate of chlorsulfuron in aqueous and soil systems were examined in laboratory studies. Aqueous hydroloysis was pH-dependent and followed pseudo-first-order degradation kinetics at 25°C, with faster hydrolysis occurring at pH 5 (half-life 24 days) than at either pH 7 or 9 (half-lives >365 days). Degradation occurred primarily by cleavage of the sulfonylurea bridge to form the major metabolites chlorobenzenesulfonamide (2-chlorobenzenesulfonamide) and triazine amine (4-methoxy-6-methyl-1,3,5-triazin-2-amine). This route is a major degradation pathway in water and soil systems. Aqueous photolysis (corrected for hydrolysis) proceeded much more slowly (half-life 198 days) than aqueous hydrolysis and is not expected to contribute significantly to overall degradation. Hydrolysis in soil thin-layer plates exposed to light (half-life 80 days), however, progressed at a much faster rate than in dark controls (half life 130 days), which suggests that a mechanism other than direct photolysis may have been operative. An aerobic soil metabolism study (25°C) in a Keyport silt loam soil (pH 6.4, 2.8% OM) showed that degradation was rapid (half-life 20 days). Dissipation in an anaerobic sediment/water system (initial pH of water phase 6.7, final pH 7.4) progressed much more slowly (half-life >365 days) than in aerobic soil systems. Major degradation products in aerobic soil included the chlorobenzenesulfonamide and triazine amine as in the aqueous hydrolysis study. Neither of these degradation products exhibited phytotoxicity to a variety of crop and weed species in a glasshouse experiment, and both exhibited an acute toxicological profile similar to that of chlorsulfuron in a battery of standard tests. Demethylation of the 4-methoxy group on the triazine moiety and subsequent cleavage of the triazine ring is another pathway found in both aqueous solution and soils, though different bonds on the triazine amine appear to be cleaved in the two systems. Hydroxylation of the benzenesulfonamide moiety is a minor degradation pathway found in soils. Two soils amended with 0.1 and 1.0 mg kg ⁻¹ chlorsulfuron showed slight stimulation of nitrification. The 1.0 mg kg ⁻¹ concentration of chlorsulfuron resulted in minor stimulation and inhibition of ¹⁴C-cellulose and ¹⁴C-protein degradation, respectively, in the same soils. Batch equilibrium adsorption studies conducted on four soils showed that adsorption was low in this system (Kₒ^D[c 13-54). Soil thin-layer chromatography of chlorsulfuron (R^D[f = 0.55-0.86) and its major degradation products demonstrated that the chlorobenzenesulfonamide (R^D[f = 0.34-0.68) had slightly less mobility and that the triazine amine (R^D[f = 0.035-0.40) was much less mobile than chlorsulfuron. In an aged column leaching study, subsamples of a Fallsington sandy loam (pH^D[wₐ^D[tₑ^D[r 5.6, OM 1.4%) or a Flanagan silt loam (pH^D[wₐ^D[tₑ^D[r 6.4, OM 4.0%) were treated with chlorsulfuron, aged moist for 30 days in a glasshouse and then placed upon a prewet column of the same soil type prior to initiation of leaching. This treatment resulted in the retention of much more total radioactivity (including degradation products) than by a prewet column, where initiation of leaching began immediately after chlorsulfuron application, without aging (primarily chlorsulfuron parent)."
Language:English
References:83
Note:Figures
Tables
Graphs
ASA/CSSA/SSSA Citation (Crop Science-Like - may be incomplete):
Strek, H. J. 1998. Fate of chlorsulfuron in the environment: 1. Laboratory evaluations. Pest Manage. Sci. 53(1):p. 29-51.
Fastlink to access this record outside TGIF: https://tic.msu.edu/tgif/flink?recno=44622
If there are problems with this record, send us feedback about record 44622.
Choices for finding the above item:
Web URL(s):
http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1096-9063(199805)53:1<29::AID-PS749>3.0.CO;2-A/epdf
    Last checked: 10/07/2015
    Requires: PDF Reader
    Access conditions: Item is within a limited-access website
Find Item @ MSU
MSU catalog number: SB 951 .A1 P45
Find from within TIC:
   Digitally in TIC by record number.
Request through your local library's inter-library loan service (bring or send a copy of this TGIF record)