Degradation of Prototype Pesticides Submitted to Conventional Water Treatment Conditions: The Influence of Major Parameters

• Published in: Water, air, and soil pollution Vol. 211; no. 1-4; pp. 427 - 434
• Main Authors: Souza, Amauri G, Costa, Letícia M, Augusti, Rodinei, Cardeal, Zenilda L
• Format: Journal Article
• Language: English
• Published: Dordrecht Dordrecht : Springer Netherlands 01-09-2010; Springer Netherlands; Springer; Springer Nature B.V
• Subjects: Analysis; Applied sciences; Aqueous solutions; Atmospheric Protection/Air Quality Control/Air Pollution; Biodegradation; Chromatography; Climate Change/Climate Change Impacts; Degradation; Earth and Environmental Science; Endosulfan; Environment; Environmental monitoring; Exact sciences and technology; Hydrogeology; Insecticides; Light; Mass spectrometry; Media; Mineralization; Nuclear radiation; Organic compounds; Organochlorine compounds; Organochlorine pesticides; Organophosphorus pesticides; PCB; Pesticides; Phorate; Pollution; Polychlorinated biphenyls; Purification; Pyrethroids; Sampling; Scientific imaging; Sodium; Soil Science & Conservation; Solid phase methods; Spectrometry; Stations; Studies; Sulfates; Toxicity; Ultraviolet radiation; Water; Water pollution; Water Quality/Water Pollution; Water treatment; Organophosphorus; Degradation; Sodium hypochloride; pH; Pyrethroid pesticides; UV irradiation; Organochlorine; Sulfur compounds; Agricultural chemical product; Water treatment; Insecticide; Pyrethroids; Sulfates; Chemical pollution; Organochlorine compounds; Chlorine Organic compounds; Sampling; Organic compounds; Pesticides; Heavy metal; Solid phase microextraction; Trace element; Gas chromatography; Ultraviolet radiation; Depletion; Surveillance; Organophosphorus compounds; Mass spectrometry
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-009-0311-6

The behavior of several pesticides in aqueous solution, namely bifenthrin, amethrin (pyrethroid insecticides), endosulfan and endosulfan sulfate (organochlorine pesticides), disulfoton, methyl pyrimiphos, and phorate (organophosphorus pesticides), submitted to the conditions typically employed in water treatment stations was investigated. Continuous pesticide depletion was monitored by solid-phase microextraction sampling followed by gas chromatography-mass spectrometry analysis. The influence of major parameters (sodium hypochloride concentration, solution pH, and exposure time to ultraviolet (UV) light) was, thus, adequately established via two complementary approaches: factorial (2³, three variables—two levels) and Doehlert designs. Hence, the sodium hypochloride concentration and the solution pH produced distinct effects depending on the pesticide evaluated (for instance, acidic and basic media caused increasing rates of degradation for the organophosphorus/pyrethroid and organochlorine pesticides, respectively). Conversely, higher rates of degradation were achieved for all of the pesticides investigated when increased exposure times to UV radiation were employed. Finally, the exposure time to UV radiation that lead to complete degradation of disulfoton and endosulfan sulfate (organophosphorus and organochlorine pesticides, respectively) in aqueous media under ordinary conditions employed in water treatment stations was established; disulfoton and endosulfan sulfate were completely degraded after 10 and 40 h, respectively.