HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Scrano, L. Articles by Shramm, K. W. Search for Related Content PubMed PubMed Citation Articles by Scrano, L. Articles by Shramm, K. W. Agricola Articles by Scrano, L. Articles by Shramm, K. W. Related Collections Agricultural Pesticides Ecological Risk Assessment Organic Compounds Soil Pollution Water Pollution Soil Chemistry

TECHNICAL REPORT
Organic Compounds in the Environment

Photochemistry and Photoinduced Toxicity of Acifluorfen, a Diphenyl-Ether Herbicide

^a Dipartimento di Produzione Vegetale, Università della Basilicata, Via N. Sauro 85, I 85100 Potenza, Italy
^b Dipartimento di Chimica, Università della Basilicata, Via N. Sauro 85, I 85100 Potenza, Italy
^c L.A.C.E., Université Claude Bernard Lyon I, 43 Bd du 11 novembre 1918, F 69622 Villeurbanne Cedex, France
^d GSF-National Research Centre for Environment and Health, Institute of Ecological Chemistry, Ingolstädter Landstrasse 1, D 85764 Neuherberg-München, Germany

* Corresponding author (bufo{at}unibas.it)

Received for publication February 9, 2001. Photochemistry studies can be helpful in assessing the environmental fate of chemicals. Photochemical reactions lead to the formation of by-products that can exhibit different toxicological properties from the original compound. For this reason the photochemical behavior of the herbicide acifluorfen (5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid) in the presence of different solvents was studied. Photochemical reactions were carried out using a high-pressure mercury arc and a solar simulator. Kinetic parameters and quantum yields were determined. The identification of photoproducts was performed by mass spectrometry and [¹H] nuclear magnetic resonance (NMR). Nitrofluorfen, hydroxy-nitrofluorfen, 2-chloro-4-(trifluoromethyl)phenol, 5-trifluoromethyl-5'-nitrodibenzofuran, and other derivatives were identified. The photochemical reactions were also carried out in the presence of either a singlet or a triplet quencher, and in the presence of either a radical initiator or a radical inhibitor. Substances used as inhibitors of the excited levels T₁ and S₁ showed that photodegradation of acifluorfen begins from a singlet state S₁ through a ,* transition. The role of free radicals in the photodegradation of acifluorfen was determined and a radical mechanism was proposed. Toxicity tests against Daphnia magna Strauss showed that acifluorfen was not toxic at a concentration of 0.1 mM; however, photoproducts formed after 36 h of UV exposure of the herbicide induced a remarkable toxicity to the test organism.

This article has been cited by other articles:

				L. Scrano, S. A. Bufo, T. R. I. Cataldi, and T. A. Albanis Surface Retention and Photochemical Reactivity of the Diphenylether Herbicide Oxyfluorfen J. Environ. Qual., March 1, 2004; 33(2): 605 - 611. [Abstract] [Full Text] [PDF]