The levels of pesticides in water have increased due to their excessive use in the modern agricultural domain Choosing a suitable water treatment method for pesticide removal depends on the type of pesticide and the efficacy of the treatment process This review critically discusses and provides a detailed description of a variety of chemical, physical, and biological approaches for pesticide removal from water, such as advanced oxidation processes, adsorption, activated sludge, membrane bioreactors, and membrane technologies Both single-treatment and hybrid methods are thoroughly described and critically discussed The use of hybrid removal techniques offers potential opportunities to develop innovative pesticide removal techniques A thorough analysis of influent composition and recognition of the best removal technique is very important to design a water treatment plant that targets the maximum possible removal rate for different types of pesticides Furthermore, the decentralization of water treatment was also discussed in which it is an important approach that would lead to better effluent water quality for lower prices Many affordable techniques such as activated sludge and adsorption by agricultural adsorbents showed high efficacy in treating high levels of different pesticides

Removal of pesticides from water and wastewater: Chemical, physical and biological treatment approaches

2D/2d heterojunction of MoS2/g-C3N4 nanoflowers for enhanced visible-light-driven photocatalytic and electrochemical degradation of organic pollutants

Degradation and mineralization of ibuprofen (IBU) were investigated using Ultraviolet (UV) Light Emitting Diodes (LEDs) in TiO 2 photocatalysis. Samples of ultrapure water (UP) and a secondary treated effluent of a municipal wastewater treatment plant (WWTP), both spiked with IBU, as well as a highly concentrated IBU (230 mg L −1 ) pharmaceutical industry wastewater (PIWW), were tested in the TiO 2 /UV-LED system. Three operating parameters, namely, pH, catalyst load and number of LEDs were optimized. The process efficiency was evaluated in terms of IBU removal using high performance liquid chromatography (HPLC) and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Additionally, the mineralization was investigated by determining the dissolved organic carbon (DOC) content. The chemical structures of transformation products were proposed based on the data obtained using liquid chromatography with a high resolution mass spectrometer ion trap/time-of-flight (LC-MS-IT-TOF). A possible pathway of IBU degradation was accordingly suggested. Bioassays were performed using the marine bacterium Vibrio fischeri to evaluate the potential acute toxicity of original and treated wastewaters. TiO 2 heterogeneous photocatalysis was efficient to remove IBU from UP and from PIWW, and less efficient in treating the wastewater from the municipal WWTP. The acute toxicity decreased by ca. 40% after treatment, regardless of the studied matrix.

Heterogeneous Photocatalytic Degradation of Ibuprofen in Ultrapure Water, Municipal and Pharmaceutical Industry Wastewaters Using a TiO2/UV-LED System

Stir bar sorptive extraction (SBSE) has been developed nearly 20 years ago and was commercialized as Twister very soon after its introduction. Main appreciated features by its users are the solventless extraction, predictable extraction efficiencies, very high sensitivities when applied in combination with thermal desorption (TD) - GC-MS, multiple use for determinations in gaseous and aqueous matrices and excellent repeatability and reproducibility when polydimethylsiloxane (PDMS) is applied as sorptive phase. These features originate from the unique characteristics of PDMS, with low glass transition temperature, very low bleeding profile at high temperatures after appropriate conditioning, and excellent diffusivity and permeability. PDMS-SBSE is intensively applied in different areas (environmental, food, biofluids, drugs, etc.) for sensitive determinations of solutes with a log P larger than 3. Of utmost importance for routine application of SBSE are its figures of merit and several studies have illustrated that SBSE on PDMS can be validated and standard operating procedures developed. For more polar solutes, different derivatization methods have been applied to enhance the hydrophobicity of the solutes and thus increasing the log P value. Over the years, other coating materials have been evaluated and/or developed for enhanced extraction of more polar compounds. Only a limited number, however, are operating in the sorptive or partitioning mode while only few of them have favorable thermal characteristics to be used in TD-GC-MS applications. To the best of our knowledge, only one has been commercialized namely a PDMS/ethylene glycol (EG) copolymer placed on an inert metal grid for mechanical stabilization. Other home-made coatings, such as monoliths, polyurethane foams or other polymers are mostly used in combination with liquid desorption, are not commercially available in ready-to-use stir bar format and, therefore, not accessible for independent in-depth testing. Alternatively, two other methods applying PDMS stir bars were recently developed to extend SBSE to more polar solutes: solvent assisted SBSE (SA-SBSE) and ice concentration linked with extractive stirrer (ICECLES) that is based on freeze concentration. This review on SBSE is highlighting both developments and future perspectives of SBSE are outlined.

Two decades of stir bar sorptive extraction: A retrospective and future outlook

In recent years, the application of heterogeneous photocatalytic water purification process has gained wide attention due to its effectiveness in degrading and mineralizing the recalcitrant organic compounds as well as the possibility of utilizing the solar UV and visible light spectrum. This paper aims to review and summarize the recently published works on the titanium dioxide (TiO2) photocatalytic oxidation of pesticides and phenolic compounds, predominant in storm and waste water effluents. The effect of various operating parameters on the photocatalytic degradation of pesticides and phenols are discussed. Results reported here suggested that the photocatalytic degradation of organic compounds depends on the type of photocatalyst and composition, light intensity, initial substrate concentration, amount of catalyst, pH of the reaction medium, ionic components in water, solvent types, oxidizing agents/electron acceptors, catalyst application mode, and calcinations temperature in water environment. A substantial amount of research has focused on the enhancement of TiO2 photocatalysis by modification with metal, non-metal and ion doping. Recent developments in TiO2 photocatalysis for the degradation of various pesticides and phenols are also highlighted in this review. It is evident from the literature survey that photocatalysis has shown good potential for the removal of various organic pollutants. However, still there is a need to find out the practical utility of this technique on commercial scale.

Influence of parameters on the heterogeneous photocatalytic degradation of pesticides and phenolic contaminants in wastewater : a short review

Headspace sorptive extraction for the detection of combustion accelerants in fire debris.

Mobility of insecticide residues and main intermediates in a clay-loam soil, and impact of leachate components on their photocatalytic degradation.

Reclamation of agro-wastewater polluted with thirteen pesticides by solar photocatalysis to reuse in irrigation of greenhouse lettuce grown.

We have demonstrated the potential leaching of eight compounds, one insecticide (flonicamid) and seven fungicides (myclobutanil, penconazole, boscalid, difenoconazole, trifloxystrobin, pyraclostrobin and fenpyroximate) trough a typical Mediterranean soil (Calcaric regosol). The concentrations found in leaching water were in all cases above the limit set by the EU in groundwater (0.1 μg L−1). For this, the efficiency of different homogeneous (photo-Fenton and photo-Fenton-like) and heterogeneous (ZnO and TiO2) photocatalytic systems was tested in deionized water to choose the most appropriate treatment to remove pesticide residues from leaching water. The efficiency was in the order: ZnO + S2O82− (pH 7) > TiO2+ S2O82− (pH 7) > ZnO (pH 7) > TiO2 (pH 7) > Fe3+ (pH 3) > Fe3+ (pH 5) > Fe2+ (pH 3) > Fe2+ (pH 5). Thus, in the subsequent experiment we focus on the efficacy of solar heterogeneous photocatalysis (ZnO/Na2S2O8 and TiO2/ Na2S2O8) on their removal from leaching water. A fast removal was observed for all pesticides at the end of the photoperiod, noticeably higher in the case of ZnO system, with the exception of flonicamid, a recalcitrant pesticide where the degradation rate only reached about 20% after 240 min of solar exposure. Although the mineralisation of the initial dissolved organic carbon was not complete due to the presence of interfering substances in the leaching water, the conversion rate under ZnO/Na2S2O8 treatment was about 1.3 times higher than using TiO2/Na2S2O8.

Marina Aliste

Papers

Headspace sorptive extraction for the detection of combustion accelerants in fire debris.

Mobility of insecticide residues and main intermediates in a clay-loam soil, and impact of leachate components on their photocatalytic degradation.

Reclamation of agro-wastewater polluted with thirteen pesticides by solar photocatalysis to reuse in irrigation of greenhouse lettuce grown.

Solar-driven photocatalytic treatment as sustainable strategy to remove pesticide residues from leaching water.

Analysis of gunshot residues as trace in nasal mucus by GFAAS