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In many European regions, people may use pesticides, particularly carbamate and organophosphorus insecticides, to deliberately poison wildlife in response to various resource-based conflicts. Repercussions of this largely illegal practice are well-documented in macro-scavengers (vultures). In southern Spain, our environmental agents are trained to gather evidence at suspected scenes of wildlife/environmental crime, including arthropods found at animal carcasses and prepared baits. Between 2008 and 2019, pesticide residues were detected in a subset of pooled or uniquely insect samples (n = 46 instances; 12 consisting solely of arthropods). Four carbamate pesticides and/or associated metabolites were detected: aldicarb/aldicarb sulfoxide, carbofuran/3-hydroxycarbofuran, methomyl/methiocarb, either qualitatively (thin layer chromatography) or quantitatively (liquid/gas chromatography), reaching concentrations of 3.05 mg/kg (aldicarb) and 9.98 mg/kg (methiocarb). Residues have mostly been detected in beetles, but also blowfly, centipede, woodlouse and notably, European honey bee, in a suspected case of deliberate hive poisoning. Implications for insect conservation: None of the aforementioned information is currently being recorded or disseminated for arthropod conservation purposes. We therefore aimed to (1) generate awareness of the deliberate wildlife poisoning practice as it may affect local necrophagous and associated insect communities; (2) share our process of sample collection, species identification and toxicological analyses to meet wildlife/environmental crime investigation requirements; (3) stimulate interest in collaborative studies to more systematically examine/document any potential effects of the practice on susceptible arthropods species relative to their population status and ecosystem services provision; (4) outline how this additionally gathered entomological information could also be used to strengthen wildlife/environmental forensics investigations.

Present work reports preparation of colloidal single/few layer Ti3C2Tx MXene flakes using minimally intensive layer delamination (MILD) method for rapid electroanalytical screening of carbamate pesticides. Lithium fluoride salt and hydrochloric acid (7.5 M LiF/9M HCl) was used to produce in-situ generated HF as etchant to remove Al successfully from Ti3AlC2 MAX phase. Unlike the clay method (5 M LiF/6M HCl), this methodology simplified Ti3C2Tx synthesis protocol resulting in Li+ ions intercalated Ti3C2Tx which was delaminated without further sonication. The delaminated Ti3C2Tx flakes were found to be single/few layered sheets with mostly –OH and –O terminated surface groups. The characteristic 002 peak observed in X-ray diffraction (XRD) at 2θ = 6.4° with interplaner distance of 1.1137 nm suggested broadening of the peak attributed to the presence of Li+ ions between Ti3C2Tx flakes. Delaminated Ti3C2Tx flakes were utilized as working electrode which demonstrated simultaneous and selective detection of carbamate pesticides methiocarb and diethofencarb by voltammetry. The oxidation peaks of the two pesticides were well separated by a potential difference of 0.35 V in 0.5 M H2SO4 and DPV detection limits were calculated as 0.19 μg mL−1 and 0.46 μg mL−1 for methiocarb and diethofencarb respectively. Ti3C2Tx flakes as electrochemical sensor exhibited long term stability and acceptable recoveries in real sample for environmental applications.

It is highly advantageous to devise an in vitro platform that can predict the complexity of an in vivo system. The first step of this process is the identification of a xenobiotic whose monooxygenation is carried out by two sequential enzymatic reactions. Pesticides are a good model for this type of tandem reactions since in specific cases they are initially metabolised by human flavin-containing monooxygenase 1 (hFMO1), followed by cytochrome P450 (CYP). To assess the feasibility of such an in vitro platform, hFMO1 is immobilised on glassy carbon electrodes modified with graphene oxide (GO) and cationic surfactant didecyldimethylammonium bromide (DDAB). UV-vis, contact angle and AFM measurements support the effective decoration of the GO sheets by DDAB which appear as 3 nm thick structures. hFMO1 activity on the bioelectrode versus three pesticides; fenthion, methiocarb and phorate, lead to the expected sulfoxide products with K

Cold plasma technology is an advanced oxidation process (AOP), which has shown significant potential for pesticide degradation. The aim of this study was to determine the degradation efficacy and transformation products for cold plasma treated carbamates in water. The dissipation of three carbamates, namely, carbaryl, methiocarb and aminocarb were evaluated as a function of treatment voltage (70, 80, and 90 kV) and duration (1 to 5 min) using a dielectric barrier discharge. Significant and rapid reduction in the concentrations of carbaryl, methiocarb and aminocarb were observed after cold plasma treatment. A maximum degradation of 50.5% in carbaryl, 99.6% in methiocarb and 99.3% in aminocarb was achieved after 5 min of treatment at an applied voltage of 90 kV. The plasma light emission was evaluated using optical emission spectroscopy revealing the production of reactive oxygen and nitrogen species, besides gas temperatures closer to ambient. The reaction intermediates were identified mostly as oxidation products from the respective carbamates, and reaction pathways were proposed. The toxicity of the degradation products, where available, was reviewed. Overall, this study shows the potential of cold plasma technology as an alternative approach for rapid dissipation of agrochemicals and other micro-pollutants in water and wastewater.

The goal of this study was to perform in silico identification of bioinsecticidal potential of 42 monoterpenes against Drosophila melanogaster and Reticulitermes chinensis Snyder. Quantitative structure-activity relationship (QSAR) modeling was performed for both organisms, while docking and molecular dynamics were used only for Drosophila melanogaster. Neryl acetate has the lowest interaction energy (-87 kcal/mol) against active site of acetylcholinesterase, which is comparable to the ones of methiocarb and pirimicarb (-90 kcal/mol) and reported PDB binder 9-(3-iodobenzylamino)-1,2,3,4-tetrahydroacridine (-112.67 kcal/mol). Interaction stability was verified by molecular dynamics simulations and showed that the stability of ACHE active site complexes with three selected terpenes is comparable to the one of the pirimicarb and methiocarb. Overall, our results suggest that pulegone, citronellal, carvacrol, linalyl acetate, neryl acetate, citronellyl acetate, and geranyl acetate may be considered as a potential pesticide candidates.

Quantitative determination of targeted and untargeted pesticide residues from food products is very important for the assessment of safety of the food products. In the present work, a simple, selective and sensitive method based on liquid chromatography atmospheric pressure chemical ionization high energy collisional dissociation high-resolution tandem mass spectrometry (LC-APCI-HCD-HRMS/MS) for quantification of 19 priority organophosphorus and carbamate pesticides and 10 untargeted pesticides from coconut milk samples was developed and validated. The pesticide residues were extracted by solvent partition followed by dispersive solid-phase extraction clean-up and quantified by LC-APCI-HRMS/MS technique. The method showed the linearity for targeted pesticides in the range of 0.5–1000 ng/g with a limit of detection of ranging 0.5–5 ng/g and limit of quantification of ranging 1–10 ng/g measured at 3:1 and 10:1 signal to noise ratios, respectively. The untargeted pesticide residues were quantified by the response factor method. The method was validated for intraday and interday precision, which was less than 15%. The recovery of the analytes varied between 82 and 117%, and the developed method was applied for the analysis of the coconut milk samples. The analyzed samples showed the presence of quinalphos, malathion, and methiocarb at concentrations of 4.55, 5.54, and 206.99 ng/g.

Funder: Università degli Studi di Padova, Systemic insecticides such as neonicotinoids are widely used in seed coating practices for pest control in many crops, e.g., corn. Their success is due to their ability to protect the whole plant, from the roots to the upper leaves, but their use at high amounts is causing possible adverse effects on non-target animals exposed to contaminated pollen, nectar, leaves, and dust emitted during sowing. In 2018, the European Union banned some neonicotinoids and fipronil as seed coating insecticides in open fields. Consequently, the methylcarbamate methiocarb and less-toxic neonicotinoids, e.g., thiacloprid, have been authorized and largely used as alternative pesticides for corn seed coating. Here, an analytical protocol based on QuEChERS extraction/purification procedure and analysis by liquid chromatography-mass spectrometry has been optimized for the identification and the quantification of methiocarb, thiamethoxam, thiacloprid, and their metabolites in guttation drops, the xylem fluid excreted at leaf margins, and in leaves of corn plants grown from coated seeds. Although methiocarb is a non-systemic pesticide, we unexpectedly found high concentrations of its metabolites in both guttations and leaves, whereas methiocarb itself was below detection limits in most of the samples. The methiocarb main metabolite, methiocarb sulfoxide, was found at a mean concentration of 0.61 ± 1.12 µg mL−1 in guttation drops and 4.4 ± 2.1 µg g−1 in leaves. Conversely, parent compounds of neonicotinoids (thiamethoxam, thiacloprid) are systemically distributed in corn seedlings. This result raises safety concerns given that methiocarb sulfoxide is more toxic than the parent compound for some non-target species.

Straw burning destroys some wildlife which would benefit if burning was restricted by law. Burning also reduces weed and cereal regrowth populations and in its absence their control may require additional herbicide treatment, for example with paraquat, which kills plants quickly and is toxic to aphids, thus preventing the spread of Barley Yellow Dwarf Virus. Slugs are favoured by straw either on the surface or incorporated into the soil and recently there has been a large increase in the use of molluscicides, especially methiocarb. The influence of three methods of straw disposal were studied in relation to two drilling techniques and to the use of methiocarb. More aphids and more virus was found in direct drilled winter wheat following methiocarb treatment. In winter barley more virus was found on ploughed than on direct drilled plots. It is suggested that these effects result from the impact of treatments on the natural enemies of aphids. The implications of using broad-spectrum pesticides in relation to straw disposal are discussed.

The conclusions of EFSA following the peer review of the initial risk assessments carried out by the competent authorities of the rapporteur Member State the United Kingdom and co‐rapporteur Member State Germany for the pesticide active substance methiocarb are reported. The context of the peer review was that required by Commission Implementing Regulation (EU) No 844/2012. The conclusions were reached on the basis of the evaluation of the representative use of methiocarb as an insecticide and a bird repellent on maize. The reliable end points, appropriate for use in regulatory risk assessment, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.

The occurrence of micropollutants in the environment is a matter of high concern. Some regulations have been published in the last years and a Watch List of contaminants of emerging concern (CECs) for European Union monitoring of surface water was launched in the Decision 2015/495, including three estrogens (estrone, E1; 17-β-estradiol, E2; and 17-α-ethinylestradiol, EE2), four pharmaceuticals (diclofenac and the macrolide antibiotics azithromycin, clarithromycin and erythromycin), an anti-oxidant (2,6-ditert-butyl-4-methylphenol, BHT), an UV filter (2-ethylhexyl 4-methoxycinnamate, EHMC), some pesticides (methiocarb and the neonicotinoids imidacloprid, thiacloprid, thiamethoxam, clothianidin and acetamiprid) and two herbicides (oxadiazon and triallate). This study provides the first spatial and seasonal monitoring campaign in the Ave and the Sousa Rivers for the all set of the 17 Watch List CECs (not reported yet for any country), in order to assess their occurrence, distribution, frequency and risk assessment. It also highlights the need of extend the study to other regions and environmental matrices to investigate the occurrence and possible sources of contamination of CECs, aiming to give insights for decision makers to define mitigation strategies for a more sustainable water policy.

Background: The use of polypharmacy in the present day clinical therapy has made the identification of clinical drug-drug interaction risk an important aspect of drug development process. Although many drugs can be metabolized to sulfoxide and/or sulfone metabolites, seldom is known on the CYP in-hibition potential and/or the metabolic fate for such metabolites. Objective: The key objectives were: a) to evaluate the in vitro CYP inhibition potential of selected parent drugs with sulfoxide/sulfone metabolites; b) to assess the in vitro metabolic fate of the same panel of par-ent drugs and metabolites. Methods: In vitro drug-drug interaction potential of test compounds was investigated in two stages; 1) assessment of CYP450 inhibition potential of test compounds using human liver microsomes (HLM); and 2) assessment of test compounds as substrate of Phase I enzymes; including CYP450, FMO, AO and MAO using HLM, recombinant human CYP enzymes (rhCYP), Human Liver Cytosol (HLC) and Human Liver Mitochondrial (HLMit). All samples were analysed by LC-MS-MS method. Results: CYP1A2 was inhibited by methiocarb, triclabendazole, triclabendazole sulfoxide, and ziprasi-done sulfone with IC50 of 0.71 µM, 1.07 µM, 4.19 µM, and 17.14 µM, respectively. CYP2C8 was in-hibited by montelukast, montelukast sulfoxide, montelukast sulfone, tribendazole, triclabendazole sulfox-ide, and triclabendazole sulfone with IC50 of 0.08 µM, 0.05 µM, 0.02 µM, 3.31 µM, 8.95 µM, and 1.05 µM, respectively. CYP2C9 was inhibited by triclabendazole, triclabendazole sulfoxide, triclabendazole sulfone, montelukast, montelukast sulfoxide and montelukast sulfone with IC50 of 1.17 µM, 1.95 µM, 0.69 µM, 1.34 µM, 3.61 µM and 2.15 µM, respectively. CYP2C19 was inhibited by triclabendazole and triclabendazole sulfoxide with IC50 of 0.25 and 0.22, respectively. CYP3A4 was inhibited by monte-lukast sulfoxide and triclabendazole with IC50 of 9.33 and 15.11, respectively. Amongst the studied sul-foxide/sulfone substrates, the propensity of involvement of CY2C9 and CYP3A4 enzyme was high (ap-proximately 56% of total) in the metabolic fate experiments. Conclusion: Based on the findings, a proper risk assessment strategy needs to be factored (i.e., perpetra-tor and/or victim drug) to overcome any imminent risk of potential clinical drug-drug interaction when sulfoxide/sulfone metabolite(s) generating drugs are coadministered in therapy.

In this paper, the use of disposable pipette extraction (DPX) for the determination of pesticides in human urine in possible cases of poisoning is proposed for the first time. The pesticides studied were oxamyl, propoxur, carbofuran, 3‑hydroxycarbofuran, carbaryl, methiocarb, terbufos, parathion methyl, malathion, chlorpyrifos and endosulfan. The pipette tip used for the extraction of these compounds was commercially acquired. It has a capacity of 5 mL and contains 20 mg of sorbent material (styrene-divinylbenzene). The optimization of the main parameters that can influence the extraction efficiency of this sample preparation technique was performed with univariate and multivariate approaches. The analytes were separated and identified by gas chromatography coupled to mass spectrometry (GC–MS). The optimal extraction conditions were 5 extraction cycles of 30 s and 5 desorption cycles of 15 s with 250 μL of ethyl acetate. Elution of the extract was performed in a vial containing 100 mg of anhydrous sodium sulfate. The method developed was validated, providing correlation coefficients higher than 0.9955 for all analytes, limits of detection (LOD) of 0.76 to 1.52 μg L−1, limits of quantification (LOQ) of 2.5 to 5.0 μg L−1, relative recoveries of 63 to 118%, intra-day precision of 0.7 to 15.3% and inter-day precision of 4.9 to 13.1%. An effective and rapid method for the analysis of human urine for the identification of possible cases of poisoning by pesticides was successful developed.

As an advanced oxidation process, vacuum ultraviolet/ultraviolet (VUV/UV) process has recently gained increasing attention in water treatment, but assessment of its technical and economic feasibility for pesticide removal has rarely been conducted. This study investigated the degradation of five typical pesticides, including aldicarb (ALD), alachlor (ALA), chloroneb (CHL), methiocarb (MET) and atrazine (ATR), by VUV/UV under simulated water treatment conditions at both bench- and pilot-scales. Bench-scale tests showed that pesticide degradation followed pseudo-first-order kinetics and all pesticides were degraded by >90% at a VUV fluence of 12 mJ cm−2. The second-order reaction rate constants of ALD, ALA, CHL, MET and ATR with HO were 7.57 × 109, 4.89 × 109, 2.57 × 109, 3.81 × 109 and 2.38 × 109 M−1 s−1, respectively. Solution pH had varying influences on the degradation of different pesticides by VUV/UV. Inorganic anions (Cl−, NO3−, HCO3−) and natural organic matter (NOM) inhibited pesticide degradation by scavenging HO , but SO42− slightly promoted pesticide degradation. The toxicity of pesticide solutions was reduced by 33.7% to 74.8% after the VUV/UV treatment. In a long-term (80 d) operation of the pilot reaction system using a sand-filtered water, the stable performance with acceptable energy consumption (0.27–1.52 kWh m−3 Order−1) suggested a good application potential of the VUV/UV process for pesticide removal in small-scale water treatment.

Vegetable crops, more than other agricultural crops, are exposed to great damages caused by slugs. Current control methods rely on chemical molluscicides that are often ineffective and harmful to non - target organisms, specially Carabids. Parasitic nematode Phasmarhabditis hermaphrodita (Schneider) parasites many slugs and snails and has been formulated as biological molluscicide. In this investigation, effectiveness of P. hermaphrodita applied in recommended and half the recommended dose in slug control in greenhouse lettuce and cabbage was evaluated and compared with metaldehyde and methiocarb pellets. Tested mollusicides did not stop feeding of Arion lusitanicus Mabille and did not achieve long term protection from slug damage. The use of standard dose of P. hermaphrodita in lettuce and cabbage provided satisfactory protection from slugs to harvest. Half recommended dose of P. hermaphrodita showed lower level of protection compared with recommended dose. Repeated applications of half recommended dose of P. hermaphrodita could boost molluscicidal effect to the level of the efficacy reached by standard dose, so it could find their place in practice. Effective control of A. lusitanicus using parasitic nematodes provides great opportunity to replace chemical molluscicides in organic production and to reduce their negative side effect to non - target organisms and the environment.

This paper describes a simple and low-cost test strip for on-site monitoring of methiocarb insecticide. Hydrophilic filter paper soaked in agarose solution was bounded by hydrophobic solid wax and then was coated with unmodified gold nanoparticles (AuNPs). AuNPs aggregation caused by methiocarb served as colorimetric response. We demonstrated detection capability of methiocarb both in solution- and substrate-based sensor. A good linear relationship was obtained between the colorimetric response and the concentration of methiocarb ranging from 20 to 80 ng mL $^{-1}$ with a limit of detection of 5 ng mL $^{-1}$ . Excellent selectivity toward methiocarb was observed among various pesticides and cationic and anionic ions. Furthermore, the proposed assay could successfully detect methiocarb in paddy and tap water with satisfactory results. It would be of interest for use as rapid, portable, and technically simple test strip in water quality monitoring.

It is possible to consult this version in open access at the following web address: arXiv:2011.11639, Water is an essential resource for all living organisms. The continuous and increasing use of pesticides in agricultural and urban activities results in the pollution of water resources and represents an environmental risk. To control and reduce pesticide pollution, reliable multi-residue methods for the detection of these compounds in water are needed. In this context, the present work aimed at providing an analytical method for the simultaneous determination of trace levels of 51 target pesticides in water and applying it to the investigation of the target pesticides in two agriculture-impacted areas of interest. The method developed, based on an isotopic dilution approach and on-line solid-phase extraction-liquid chromatography-tandem mass spectrometry, is fast, simple, and to a large extent automated, and allows the analysis of most of the target compounds in compliance with European regulations. Application of the method to the analysis of selected water samples collected at the lowest stretches of the two largest river basins of Catalonia (NE Spain), Llobregat and Ter, revealed the presence of a wide suite of pesticides in the Llobregat basin, some of them at concentrations above the water quality standards (irgarol and dichlorvos) or the acceptable method detection limits (methiocarb, imidacloprid, and thiacloprid), and much cleaner waters in the Ter River basin. Risk assessment of the pesticide concentrations measured in the Llobregat River indicated high risk due to the presence of irgarol, dichlorvos, methiocarb, azinphos ethyl, imidacloprid, and diflufenican (hazard quotient (HQ) values>10), and moderate potential risk in the Ter River, associated to the occurrence of bentazone and irgarol (HQ > 1)., This work has received funding from the European Union's Horizon 2020 - Research and Innovation Framework Programme (WaterProtect project, No. 727450), the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERDF) (BECAS project, CTM2016-75587-C2-2-R), the Spanish Ministry of Science and Innovation (Project CEX2018-000794-S), and the Government of Catalonia (2017 SGR 01404). Vinyet Solà from CUADLL and Francesc Camps Saguè from IRTA are acknowledged for their help in the collection of samples from the Llobregat River and the Ter River, respectively.

Background: Large amounts of insecticide-containing dusts produced from abrasion of the seed dressing can be released into the atmosphere during sowing operations. Neonicotinoid pesticides, introduced in the 1990s for several crops, are the leading products for seed-coating treatments in many countries. Neonicotinoid containing dusts can be efectively intercepted by bees in fight over the sowing feld, inducing lethal acute efects, so that restrictions in the use of the main neonicotinoids have been adopted in the European Union. This led to the consequent introduction of replacement insecticides for seed-coating, i.e. methiocarb and thiacloprid, despite the lack of information on both the toxicity and the exposure scenarios for honeybees. Results: In this study, a laboratory apparatus was developed in order to quantify the toxicity of the dusts produced from the abrasion of the seed coating. This quantifcation is based on (i) an airstream transporting coating particles into an exposure chamber; (ii) exposure of bees to reproducible and measurable concentrations of insecticide, and (iii) direct measurement of the exposure dose on single bees. The method allowed us to perform in vivo experiments of honeybee exposure to provide toxicity data in more realistic exposure conditions. In fact, the formulation rather than the active principle alone can be tested, and the exposure is through dusts rather than a solution so that specifc absorption behavior can be studied in representative environmental conditions. The method was used to quantify the acute toxicity (LD50) of dusts obtained from the abrasion of corn seeds coated with clothianidin, thiacloprid and methiocarb. Conclusions: Our results show that, surprisingly, the replacement insecticide methiocarb has a toxicity (LD50=421– 693 ng/bee) in the same order of magnitude as clothianidin (LD50=113–451 ng/bee) through this specifc exposure route, while thiacloprid (LD50=16.9·103 ng/bee) has a signifcantly lower acute toxicity. Moreover, dusts containing methiocarb and clothianidin show a signifcant increase in toxicity when, after exposure, bees are kept under high humidity conditions. This suggests that the method here presented can be used to obtain complementary toxicity data in the risk assessment procedure for the authorization of new seed-coating insecticides or new formulations. Keywords: Systemic insecticides, Neonicotinoids, Methiocarb, Seed coating, Abrasion dusts, Honeybees, Pollinator insects, Acute toxicity, Exposure measurement

Two stages of selection from a pool of 56 fatty acids analyzed in Helix pomatia yielded a set of 12 biomarker acids undergoing significant changes in contact with three microdoses of toxic substances, i.e. three molluscicides containing metaldehyde, methiocarb, and potassium chloride (PC). The proposed palette of acids, including saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA), determined separately in the foot tissues and hepatopancreas of Gastropoda, can be used in ecotoxicological research as a reliable test of the effect of trace doses of stressors. The final set of the biomarker FA comprised C16:0; C18:0; C23:0; C18:1 n-9; C20:1 n-9; C18:2 n-6; C18:3 n-3; C20:2; C20:4 n-6; C20:5 n-3; C22:4 n-6; and C22:5 n-3. A clear physiological response manifested as changes in the content of fatty acids (FA) was observed in the snails even in the case of the lowest doses of the pollutants. All experimental factors analyzed, i.e., the dose (5, 10, or 15 μl 0.01% w/v concentration) and the type of preparation (metaldehyde, methiocarb or PC), had a significant (p ≤ 0.01) impact on the FA composition of the foot and hepatopancreas. Limitation of the analysis to a narrow pool of reactive FA meets the requirements of parameters of biomarkers of exposure and facilitates and accelerates visualization of the bioindicator organism's response to the presence of the stressor in the environment.

A liquid chromatography method with post-column photoinduced chemiluminescence (PICL) detection is proposed for the simultaneous determination of eight carbamate pesticides, namely aldicarb, butocarboxim, ethiofencarb, methomyl, methiocarb, thiodicarb, thiofanox and thiophanate-methyl. After chromatographic separation, quinine (sensitizer) was incorporated and the flow passed through an UV lamp (67 s of irradiation time) to obtain the photoproducts, which reacted with acidic Ce(IV) and provided a CL emission. The PICL method showed great selectivity for carbamate pesticides containing sulphur in their chemical structure. A solid-phase extraction process increased sensitivity (LODs ranging from 0.06 to 0.27 ng mL−1) and allowed the carbamate pesticides in surface and ground water samples to be determined, with recoveries in the range 87 110% (except for thiophanate-methyl, whose recoveries were between 60 and 75%). The intra- and inter-day precision was evaluated, with RSD ranging from 1.1 to 7.5% and from 2.6 to 12.3%, respectively. A discussion about the PICL mechanism is also included.

Although there are no legal discharge limits for micropollutants into the environment, some regulations have been published in the last few years. Recently, a watch list of substances for European Union-wide monitoring was reported in the Decision 2015/495/EU of 20 March 2015. Besides the substances previously recommended to be included by the Directive 39/2013/EU, namely two pharmaceuticals (diclofenac and the synthetic hormone 17-alpha-ethinylestradiol (EE2)) and a natural hormone (17-beta-estradiol (E2)), the first watch list of 10 substances/groups of substances also refers three macrolide antibiotics (azithromycin, clarithromycin and erythromycin), other natural hormone (estrone (E1)), some pesticides (methiocarb, oxadiazon, imidacloprid, thiacloprid, thiamethoxam, clothianidin, acetamiprid and triallate), a UV filter (2-ethylhexyl-4-methoxycinnamate) and an antioxidant (2,6-di-tert-butyl-4-methylphenol) commonly used as food additive. Since little is known about the removal of most of the substances included in the Decision 2015/495/EU, particularly regarding realistic concentrations in aqueous environmental samples, this review aims to: (i) overview the European policy in the water field; (ii) briefly describe the most commonly used conventional and advanced treatment processes to remove micropollutants; (iii) summarize the relevant data published in the last decade, regarding occurrence and removal in aqueous matrices of the 10 substances/groups of substances that were recently included in the first watch list for European Union monitoring (Decision 2015/495/EU); and (iv) highlight the lack of reports concerning some substances of the watch list, the study of un-spiked aquatic matrices and the assessment of transformation by-products.

The electrooxidation of methiocarb and bisphenol A was studied in complex matrices, namely, simulated and real sanitary landfill leachate samples, using a boron-doped diamond anode. With simulated sanitary landfill leachate samples, the influence of the type and ratio of carbon source (glucose/humic acid) and electrolyte (NaCl or Na2SO4) on the emerging contaminants removal was assessed. Using real sanitary landfill leachate, the influence of current density was evaluated. The experimental results showed that electrooxidation, using a boron-doped diamond anode, can be successfully utilized to degrade methiocarb and bisphenol A when present in complex matrices, such as sanitary landfill leachate, and that methiocarb is more easily oxidized than bisphenol A. Furthermore, it was found that the presence of chloride and high humic acid content increases emerging contaminants removal rate, showing that electrooxidation at boron-doped diamond is particularly adequate to solve the problems raised by sanitary landfill leachate, even when contaminated with emerging contaminants.

This paper aims to review the existing occurrence data in Spanish groundwater (GW) for the emerging organic contaminants (EOCs) defined in the surface water Watch Lists of Decisions 2015/495/EU and 2018/840/EU since these contaminants are likely to reach GW bodies because surface waters show close interaction with GW. These two lists include 20 substances: 9 pesticides (5 neonicotinoids, 2 carbamates, 1 oxadiazole and 1 semicarbazone), 6 pharmaceuticals (diclofenac and 5 antibiotics), 3 estrogens, 1 UV filter (2-ethylhexyl-4-methoxycinnamate, EHMC) and 1 antioxidant (2,6-di-tert-butyl-4-methylphenol, BHT). Most of these substances are usually detected at low ng/L concentration range or not detected in the GW bodies of Spain. However, eventually they are reported at concentrations > 100 ng/L (e.g., imidacloprid, methiocarb, diclofenac, macrolide antibiotics, ciprofloxacin, EHMC and BHT). Consequently, it is required to set up drinking water standards, and/or GW threshold quality values because GW is a valuable water resource worldwide. Overall, GW is less contaminated than other water bodies, such as rivers, suggesting that aquifers possess a natural attenuation capacity and/or are less vulnerable than rivers to contamination. Nevertheless, the natural hydrogeochemical processes that control the fate and transformation of these substances during infiltration and in the aquifer have been barely investigated so far. The concentrations of the target EOCs are used to calculate hazard quotients (HQs) in the Spanish GW bodies as an estimation of their ecotoxicity and in order to compare somehow their chemical quality with respect to those of surface water. Due to the limited ecotoxicity data for most EOCs, HQs can only be calculated for few substances. The results pointed out the risk posed by the anti-inflammatory diclofenac towards Ceriodaphnia dubia (HQ = 21) and the medium risk associated to the antibiotic erythromycin for Brachionus calyciflorus (HQ = 0.46). © 2019 Elsevier B.V., AJ gratefully acknowledges the financial support from the Excellence Initiative of the German Federal and State Governments through the “Open Topic Postdoc Position” Fellow at the Technische Universität Dresden . MSDC acknowledges the Spanish Ministry of Science, Innovation and University and the European Commission (Project ACWAPUR PCIN 2015-245 ). Appendix A

A method for the determination of 200 pesticides and pesticide metabolites in honeybee samples has been developed and validated. Almost 98% of compounds included in this method are approved to use within European Union, as active substances of plant protection products or veterinary medicinal products used by beekeepers to control mites Varroa destructor in hives. Many significant metabolites, like metabolites of imidacloprid, thiacloprid, fipronil, methiocarb and amitraz, are also possible to detect. The sample preparation was based on the buffered QuEChERS method. Samples of bees were extracted with acetonitrile containing 1% acetic acid and then subjected to clean-up by dispersive solid phase extraction (dSPE) using a new Z-Sep+ sorbent and PSA. The majority of pesticides, including neonicotionoids and their metabolites, were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) but some of pesticides, especially pyrethroid insecticides, were analyzed by gas chromatography tandem mass spectrometry (GC-MS/MS). The procedure was validated according to the Guidance document SANCO/12571/2013 at four concentration levels: 1, 5, 10 and 100 ng/g bees and verified in the international proficiency test. The analysis of bee samples spiked at the limit of quantification (LOQ) showed about 98% mean recovery value (trueness) and 97% of analytes showed recovery in the required range of 70-120% and RSDr (precision) below 20%. Linearity and matrix effects were also established. The LOQs of pesticides were in the range of 1-100 ng/g. The developed method allows determination of insecticides at concentrations of 10 ng/g or less, except abamectin and tebufenozide. LOQ values are lower than the median lethal doses LD50 for bees. The method was used to investigate more than 70 honeybee poisoning incidents. Data about detected pesticides and their metabolites are included.

The oxidative, reductive, and hydrolytic metabolism of methiocarb and the hydrolytic metabolism of carbaryl by liver microsomes and plasma of rats or humans were examined. The effects of the metabolism of methiocarb and carbaryl on their nuclear receptor activities were also examined. When methiocarb was incubated with rat liver microsomes in the presence of NADPH, methiocarb sulfoxide, and a novel metabolite, methiocarb sulfone were detected. Methiocarb sulfoxide was oxidized to the sulfone by liver microsomes and reduced back to methiocarb by liver cytosol. Thus, the interconversion between methiocarb and the sulfoxide was found to be a new metabolic pathway for methiocarb by liver microsomes. The product of methiocarb hydrolysis, which is methylthio-3,5-xylenol (MX), was also oxidized to sulfoxide form by rat liver microsomes. The oxidations were catalyzed by human flavin-containing monooxygenase isoform (FMO1). CYP2C19, which is a human cytochrome P450 (CYP) isoform, catalyzed the sulfoxidations of methiocarb and MX, while CYP1A2 also exhibited oxidase activity toward MX. Methiocarb and carbaryl were not enzymatically hydrolyzed by the liver microsomes, but they were mainly hydrolyzed by plasma and albumin to MX and 1-naphthol, respectively. Both methiocarb and carbaryl exhibited PXR and PPARα agonistic activities; however, methiocarb sulfoxide and sulfone showed markedly reduced activities. In fact, when methiocarb was incubated with liver microsomes, the receptor activities were decreased. In contrast, MX and 1-naphthol showed nuclear receptor activities equivalent to those of their parent carbamates. Thus, the hydrolysis of methiocarb and carbaryl and the oxidation of methiocarb markedly modified their nuclear receptor activities.

In this work, a simple, inexpensive, reliable, and environmentally friendly sample preparation method based on solidification of an ionic liquid after performing dispersive liquid–liquid microextraction has been developed for the extraction and preconcentration of four carbamate pesticides (carbofuran, methiocarb, carbaryl, and thiodicarb) followed by their determination with high performance liquid chromatography-diode array detector. For this purpose, a secondary amine is mixed with a carboxylic acid to prepare an ionic liquid with a low melting point. Then, the prepared ionic liquid is used as an extraction solvent in the microextraction procedure. The effect of different parameters that can affect the extraction efficiency of the developed method was systematically investigated. Under optimum conditions low limits of detection and quantification in the ranges of 0.32–0.51 and 1.09–1.72 ng mL−1, respectively, were obtained. Enrichment factors and extraction recoveries were obtained in the ranges of 173–227 and 69–91%, respectively. Finally, the proposed method was successfully used in the determination of the selected carbamate pesticides in some fruit juice and vegetable samples at ng mL−1 level.

As the consumption of aquatic products increased, the need for regulation of pesticide residues in aquatic products also emerged. Thus, in this study, a scheduled multiple reaction monitoring (sMRM) method employing a novel extraction and purification step based on QuEChERS with EDTA was developed for the simultaneous quantitation of 20 pesticides (alachlor, aldicarb, carbofuran, diazinon, dimethoate, dimethomorph, ethoprophos, ferimzone, fluridone, hexaconazole, iprobenfos, malathion, methidathion, methiocarb, phenthoate, phosalone, phosmet, phosphamidon, pirimicarb, and simazine) in aquatic products. Additionally, the present method was validated in the aspects of specificity, linearity (r ≥ 0.980), sensitivity (the limit of quantitation (LOQ) ≤ 5 ng/g), relative standard deviation, RSD (1.0% ≤ RSD ≤ 19.4%), and recovery (60.1% ≤ recovery ≤ 117.9%). Finally, the validated method was applied for the determination of the 20 pesticide residues in eel and shrimp purchased from local food markets. In the present study, QuEChERS with EDTA was successfully expanded to residual pesticide analysis for the first time. The present method could contribute to the rapid and successful establishment of the positive list system in South Korea.

Simple dispersive liquid–liquid microextraction using a low-density solvent coupled with high-performance liquid chromatography was developed for the preconcentration and determination of methomyl, aldicarb, carbofuran, carbaryl, isoprocarb, and methiocarb. Separations were performed on a C18 column using gradient elution by methanol and 0.1% (v/v) acetic acid at 1.0 mL min−1 with ultraviolet detection at 270 nm. The separation of the six carbamate insecticides was achieved within 14 min. Parameters affecting the efficiency, including the types and volumes of extraction and dispersive solvents, sonication time, and electrolyte addition were optimized. The reported procedure is rapid, simple, and employs standard glassware without centrifugation. Under the optimum conditions, the calibration curves were linear from 5 to 10000 µ g L−1. The enrichment factors were up to 58 and the limits of detection were between 2 and 80 µ g L−1. Intra-day and inter-day precision values were determined to be less th...

Zeolite NaY modified with cetyltrimethylammonium bromide (CTAB) was considered for extraction/preconcentration of carbamate pesticides using an on-line SPE-HPLC system. The simultaneous determination of carbamate pesticides, including aldicarb, carbofuran, carbaryl, isoprocarb, methiocarb and promecarb, was performed by HPLC–UV using a LichroCART RP-18 column with gradient elution of methanol and 0.1 % acetic acid. The sorbent presented admicelles of CTAB on its surfaces and exhibited a sorption capacity of 180–18,600 mg kg−1 sorbent, which could be re-modified for at least five extraction cycles. The quantitative retention of target pesticides on the admicellar sorbent involved hydrophobic and π-cation interaction, while pesticides were eluted from the admicellar SPE column using only 750 μL of methanol. LODs and LOQs of the proposed method were 0.005–140 and 0.02–600 μg L−1, respectively. The analytes were effectively concentrated with the enrichment factors between 5 and 551. The developed on-line admicellar SPE-HPLC system was successfully applied to the determination of carbamate pesticides in ten environmental water samples from different sources. Recoveries of spiked samples at a concentration of 0.1–5 mg L−1 ranged from 77 to 111 %.

The application of molluscicides baits on the soil surface is the most common practice to control terrestrial gastropods. There seems to be a gap in the accurate evaluation of molluscicidal baits effects to soil arthropods, since their hazard to non-target organisms has been considered low after mixing baits into soil. In this work the ecotoxicological effects of two molluscicide baits (metaldehyde and methiocarb) to the collembolan Folsomia candida were evaluated using two different approaches: (1) molluscicidal baits were applied to the top soil once and only at the beginning of the exposure and avoidance behaviour and reproduction were evaluated; and (2) baits were replaced by new ones after 14-d of exposure, simulating the recommended application rate recommended by the manufacturer and reproduction was assessed (repeated/pulse exposure). A preference for the side contaminated for methiocarb was observed but the distribution of collembolans in the avoidance test with metaldehyde was random. Exposure to metaldehyde resulted in a significant increase in mortality. For methiocarb, a reduction in the juveniles produced but no acute effects were observed. In the bait pulse test, the toxic effects of each chemical was significantly increased compared with the single exposure test, for all treatments used (both reproduction and mortality). In summary, molluscicides have an adverse effect on F. candida, with severe effects on their behaviour (only for methiocarb), reproduction and survival (for both), which can lead to population collapse with time.

New faster and simpler methods for determination of pesticides in agricultural products are necessary as requirements for food safety are becoming increasingly stringent. One possibility is to introduce a fast, easy and low-cost screening method before liquid chromatography mass spectrometry analyses. We hereby present a systematic proof of concept study of paper spray mass spectrometry method for pesticide detection as a screening method. Two sampling approaches – wiping the surface with paper and applying the sample homogenate directly on the paper – were used. The wiping method was more extensively studied for imazalil and thiabendazole originally present in oranges. For homogenized samples three matrices – oranges, tomatoes and grapes – and five pesticides of different chemical nature and polarity – thiabendazole, aldicarb, imazalil, methomyl and methiocarb – were chosen. It has been shown that limits of detection below maximum residue levels can be achieved for both methods (e.g. imazalil and thiabendazole detection limits were found to be lower than 5 mg/kg). The methods are therefore suitable for fast screening of samples. Moreover, the wiping method was also applied for 11 samples – oranges, grapefruits, lemons, limes, mandarins, tomatoes, apples, pears, strawberries, grapes and sweet peppers – from the local supermarket to screen for different pesticides. Three positive samples for thiabendazole and imazalil and one positive sample for imazalil were found.

Distribution of pesticides both on the surface of leaves and in cross sections of plant stem and leaves was investigated using desorption electrospray ionization mass spectrometry imaging (DESI-MSI) with a spatial resolution of 50-100 μm. Two commercially available insecticide sprays containing different contact pesticides were applied onto leaves of Cotoneaster horizontalis, and the distributions of all active ingredients were directly analyzed. The first spray contained pyrethrins and rapeseed oil, both known as natural insecticides. Each component showed an inhomogeneous spreading throughout the leaf, based on substance polarity and solubility. The second spray contained the synthetic insecticides imidacloprid and methiocarb. Imidacloprid accumulated on the border of the leaf, while methiocarb was distributed more homogenously. In order to investigate the incorporation of a systemically acting pesticide into Kalanchoe blossfeldiana, a commercially available insecticide tablet containing dimethoate was spiked to the soil of the plant. Cross sections of the stem and leaf were obtained 25 and 60 days after application. Dimethoate was mainly detected in the transport system of the plant after 25 days, while it was found to be homogenously distributed in a leaf section after 60 days.

Multiwalled carbon nanotubes have been used for the first time as solid-phase extraction sorbents for the extraction of five N-methylcarbamate insecticides (i.e., carbaryl, carbofuran, aminocarb, methiocarb, and zectran) from different surface water samples. An effective and sensitive method was developed by combining solid-phase extraction and liquid chromatography–electrospray ionization–mass spectrometry detection. Important parameters influencing the extraction efficiency such as kind and volume of elute, volume of water samples, and adsorbent mass were optimized. Under the optimized extraction conditions, good linearity was obtained for all carbamates (r 2 > 0.995) over the range of 0.005–1 mg L−1. The limits of detection and quantification were 0.01–0.05 and 0.08–0.2 µg L−1, respectively. The optimized solid-phase extraction procedure was compared in terms of adsorption capacity to C18 silica and activated carbon. The adsorption capacity of multiwalled carbon nanotubes was larger than activated carbon. The proposed method was successfully applied to the analysis of tap and surface waters, and mean recoveries for five carbamates were from 92.2 to 103.9 % with relative standard deviation between 0.4 and 7.0 %.

ontrol studies had been conducted under laboratory and field conditions on Monacha cartusiana snail. Laboratory studies was carried out to evaluate the effect of Diesel oil on egg hatchability of the same land snail M. cartusiana with three application rates 10,20 and 30 L/Fe.Result assured that no any egg can hatching when Diesel oil applied with three application rates. On the other hand, when Diesel oil applied under field conditions to control M. cartusiana snail,with application rates 30 L/Fe., the reduction rate was 5.07% only. Regarding evalution of three application methods (hand sowing, underplant stack and piles on plastic pieces) for metaldehyde and methiocarb, under field condition. Results revealed that per cent reduction of metaldehyde and methiocarb (as ready made bait) were markedly increased when, applied as hand sowing as compared when they used as piels on plastic under plant stacked.

A microextraction procedure based on ultrasound-assisted surfactant-enhanced emulsification microextraction (UASEME) was optimized and validated for preconcentration of carbamate pesticides prior to fast determination using high-performance liquid chromatography (HPLC) with monolithic column. The nonionic surfactant (Tween 20) was used as an emulsifier, and chloroform was selected as an extraction solvent. The experimental parameters affecting the extraction efficiency, such as the kind, concentration, and volume of surfactant, the kind of extraction solvent and its volume, salt addition, ultrasonic extraction time, and centrifugation time, were optimized. Under the selected UASEME and HPLC conditions, separation of five carbamate pesticides (carbofuran, carbaryl, isoprocarb, methiocarb, and promecarb) was achieved within 10 min. The linearity of the method was obtained in the wide range of 2–5000 μg L−1, with correlation coefficients of 0.9931–0.9970. The limits of detection were in the range of 0.4–7.0 ...

Water pollution due to organophosphorus and carbamate pesticides is an important environmental issue. Pesticide analysis in water samples has received great attention for many years due to the wide use of pesticides in agricultural and household applications. The World Health Organization estimates that as many as three million people per year are poisoned by pesticides; many are due to organophosphorus pesticides, resulting in two hundred thousand deaths. In the present study an attempt is made to determine the presence of organophosphorus and carbamate pesticides and dibutylphthalate in water samples from different sources (surface and ground water) in Mysore city, Southern India, in order to understand the extent of water contamination due to pesticides and phthalates usage. Sampling points included drinking water sources, industrial areas and surface water sources closer to agricultural field. Water samples were collected from twelve sampling points and analysed using GC-MS. Organophosphorus and carbamate pesticides were not present in detectable concentration by the method adopted in any of the samples. Analysis indicated the presence of Methylisocynate (MIC) in five samples; an intermittent compound of carbamate pesticides and is harmful to health. MIC is used in the manufacturing of pesticides such as methomyl, carbofuran, aldicarb, methiocarb and carbaryl. There is evidence in literature that MIC, when comes in contact with water will hydrolyze into methylamine and N-N’dimethylurea. Literature states that carbamate pesticides often lose methylisocynate in the voltage range of 90-130 V during GC analysis. On this basis it can be concluded that the MIC identified in the water samples is a derivative of carbamate pesticides. GC- MS analysis showed the presence of Dibutylphthalate (DBP) in eight samples, a plasticizer used to impart flexibility to plastics. The results show the presence of DBP in the range of 46.79 μg/L to 212.52 μg/L in the samples analysed. USEPA specifies upper limit of 0.6 μg/L for phthalates in water. DBP pose serious health effect as it is an endocrine disrupter. DBP is listed as a priority substance in the European Union and is subjected to environmental risk assessment. Since plastics/PVC is used extensively in India, especially for the storage and distribution of water, there is a need to evolve a policy on the usage of DBP in the manufacture of plastics/PVC.

In this article, a simple and rapid method is described for voltammetric determination of methiocarb (MTC, a pesticide of the carbamate type). Direct oxidation of MTC at a highly positive potential of about +1.4 V vs. Ag/AgCl was found to be feasible, thanks to the excellent performance of the working boron-doped diamond electrode in combination with the differential pulse voltammetric ramp. After optimisation of important parameters, the signal of MTC could be calibrated in an interval of 1–55 m gm L � 1 MTC, when offering a detection limit (3s )o fca. 0.15 m gm L � 1 MTC. The practical applicability of the method has been demonstrated on analyses of a commercial pesticide, either with respect to the total content of MTC or as its gradual and time-controlled dissolution in the model sample of the natural aquatic system.

Standard and new snail baits were evaluated for the control of the brown garden snail, Helix aspersa Miiller in a vineyard. As a ground treatment, the proprietary bait Sluggem (carbaryl/metaldehyde) gave satisfactory control, whereas Mesurol (methiocarb) bait or Mesurol (methiocarb) wettable powder mixed with bran and water were less successful. The new proprietary bait formulation, Suprasnail (metaldehyde), was effective on the ground and arboreally (on the arms of the vine).

A simultaneous analytical method was developed for the determination of methiocarb and its metabolites, methiocarb sulfoxide and methiocarb sulfone, in five livestock products (chicken, pork, beef, table egg, and milk) using liquid chromatography-tandem mass spectrometry. Due to the rapid degradation of methiocarb and its metabolites, a quick sample preparation method was developed using acetonitrile and salts followed by purification via dispersive- solid phase extraction (d-SPE). Seven-point calibration curves were constructed separately in each matrix, and good linearity was observed in each matrix-matched calibration curve with a coefficient of determination (R2) ≥ 0.991. The limits of detection and quantification were 0.0016 and 0.005mg/kg, respectively, for all tested analytes in various matrices. The method was validated in triplicate at three fortification levels (equivalent to 1, 2, and 10 times the limit of quantification) with a recovery rate ranging between 76.4-118.0% and a relative standard deviation≤10.0%. The developed method was successfully applied to market samples, and no residues of methiocarb and/or its metabolites were observed in the tested samples. In sum, this method can be applied for the routine analysis of methiocarb and its metabolites in foods of animal origins.

The aim of this paper is to demonstrate the possibilities of anaerobic sludge cells immobilized into poly(vinyl alcohol) cryogel for the methanogenic conversion of various lignocellulosic waste and other media containing antibiotics (ampicillin, kanamycin, benzylpenicillin) or pesticides (chlorpyrifos or methiocarb and its derivatives). It was established that the immobilized cells of the anaerobic consortium can be stored frozen for at least three years while preserving a high level of metabolic activity. The cells after the long-term storage in an immobilized and frozen state were applied for the methanogenesis of a wide number of wastes, and an increase in both methane yield and methane portion in the produced biogas as compared to the conventionally used suspended anaerobic sludge cells, was ensured. It was shown that the &ldquo, additional&rdquo, introduction of bacterial Clostridium acetobutylicum, Pseudomonas sp., Enterococcus faecalis cells (also immobilized using same support) improves characteristics of methanogenesis catalyzed by immobilized anaerobic sludge.

This descriptive study evaluates the blood serum levels of relevant pesticides in fern/ornamental and tomato agricultural workers in central and south Florida whose work activity is related to pesticide application or crop maintenance. The objectives of this study are to broadly evaluate pesticide absorption in agricultural workers, assess personal protective equipment (PPE) use and their potential relevance to pesticide absorption, and to evaluate the feasibility of using primary biomonitoring as a method of exposure assessment for long-term epidemiological investigations. Three rounds of sampling were conducted where 41 subjects provided serum samples analyzed for individual pesticides and responded to a survey regarding PPE use. Serum samples yielded quantifiable detections of DDE, Methiocarb, Malathion, Chlorpyrifos, and Endosulfan in select subjects. The personal protective equipment survey did not demonstrate association with positive serum samples. These results demonstrate that the evaluated workers are effectively protected against exposures known to result in acute toxicity. Biomonitoring for parent compounds and primary metabolites may have limited utility in long-term epidemiological studies to evaluate chronic toxicity where workers are exposed to a great diversity of workplace chemicals (fern/or- namental workers) compared to agricultural sectors where workplace chemical diversity is more limited (tomato workers).

Methiocarb (MC) reacted with free chlorine at a stoichiometric ratio of 1:1, and the apparent rate constant was determined to be (1.19-2.46) x 10(8) M-1 s(-1) the pH range of 5.6-7.5 by competition kinetics. Methiocarb sulfoxide (MCX) and methiocarb sulfone (MCN) were identified to be the major by products of MC degradation. MCX could be further oxidized by free chlorine to MCN under acidic and neutral conditions, or hydrolyze to methiocarb sulfoxide phenol (MCXP) under basic conditions. MCN was hardly oxidized by free chlorine but hydrolyzed to methiocarb sulfone phenol (MCNP). Once formed, both MCXP and MCNP reacted with free chlorine too fast to be detectable. Due to the formation of MCX (more toxic than MC), the toxicity of the reaction solution obviously increased after chlorination. This enhanced toxicity raises a serious concern about the safety of drinking water if source water contains MC as a micropollutant. (C) 2013 Elsevier B.V. All rights reserved.

Laboratory bioassays and caged field trials were conducted to compare the acute toxicities of molluscicide formulations on the neonate, juvenile, and adult development stages of giant African snail (GAS) Lissachatina fulica (Bowdich 1822) and 3 non-target snail species in Barbados. Nine commercially available molluscicides, diatomaceous earth, and a kaolin clay product (Surround WP) were evaluated. High levels of mortality to neonate GAS were seen in all the laboratory molluscicide bioassays except for Surround and diatomaceous earth. The highest mortality rates to neonate GAS were observed from Durham granules and Slugfest treatments tested during field trials. Deadline, Durham granules, Metarex, and Orcal pellets caused the highest rates of mortality to juvenile GAS in our field trials. For adult GAS several molluscicides including Blitzem, Deadline, Durham Granules, Mesurol 75W, Metarex, Orcal pellet, and Slugfest caused greater than 95 % mortality in laboratory bioassays. Field trials showed ...

Flowers are frequently treated with pesticides and, as a result, florists handling daily a large number of flowers can be exposed to pesticide residues. A study was conducted among twenty volunteer florists located in Namur Province and in the Brussels Capital Region of Belgium in order to assess their potential dermal exposure to dislodgeable pesticide residues transferred from flowers to hands. Two pairs of cotton gloves were worn during two consecutive half days while handling flowers and preparing bouquets (from min 2 h to max 3 h/day). The residual pesticide deposits on the glove samples were extracted with a multi-residue Quick Easy Cheap Effective Rugged Safe (QuEChERS) method and analyzed by a combination of gas and liquid chromatography tandem mass spectrometry (GC-MS/MS and LC-MS/MS) by an accredited laboratory. A total of 111 active substances (mainly insecticides and fungicides) were detected, with an average of 37 active substances per sample and a total concentration per glove sample of 22.22 mg/kg. Several predictive levels of contamination were considered to assess the risk. The potential dermal exposures (PDE) of florists were estimated at the average, for different percentiles, and at the maximum concentration of residues in samples. At the PDE P90 and at the PDEMAX (or worst case) values, three and five active substances respectively exceed the Acceptable Operator Exposure Level (AOEL), indicating risk situations. For the systemic exposure (SE), one active substance (clofentezine) exceeds the AOEL at the P90 predictive level. In the worst case, SEMAX (at the maximum concentrations), four active substances (clofentezine, famoxadone, methiocarb, and pyridaben) exceed their respective AOEL values. Among the 14 most frequently detected active substances, two have SEMAX values exceeding the AOEL. Exposure could be particularly critical for clofentezine with an SEMAX value four times higher than the AOEL (393%). The exposure of florists appeared to be an example of a unique professional situation in which workers are exposed regularly to both a very high number of toxic chemicals and rather high concentration levels. Therefore the priority should be to raise the level of awareness among the florists who must change their habits and practices if they want to minimize their exposure.

Despite the high toxicity and resistance to conventional water treatments exhibited by methiocarb (MC), there are no reports regarding the degradation of this priority pesticide by means of alternative purification technologies. In this work, the removal of MC by means of ozonation was studied for the first time, employing a multi-reactor methodology and neutral pH conditions. The second-order rate constants of MC reaction with molecular ozone (O3) and formed hydroxyl radicals (OH·) were determined to be 1.7·106 and 8.2·109 M−1 s−1, respectively. During degradation experiments, direct ozone reaction was observed to effectively remove MC, but not its formed intermediates, whereas OH· could oxidize all species. The major identified TPs were methiocarb sulfoxide (MCX), methiocarb sulfoxide phenol (MCXP) and methiocarb sulfone phenol (MCNP), all of them formed through MC oxidation by O3 or OH· in combination with hydrolysis. A toxicity assessment evidenced a strong dependence on MCX concentration, even at very low values. Despite the OH· capability to degrade MC and its main metabolites, the relative resistance of TPs towards ozone attack enlarged the oxidant dosage (2.5 mg O3/mg DOC) necessary to achieve a relatively low toxicity of the medium. Even though ozonation could be a suitable technique for MC removal from water compartments, strategies aimed to further promote the indirect contribution of hydroxyl radicals during this process should be explored.

Cyclic voltammogram of methiocarb in 0.1 M H2SO4 exhibited an irreversible anodic peak at about +1285 mV versus Ag/AgCl. Electro-oxidation and determination of methiocarb in spiked soil, river water and agrochemical formulation were realized on a newly prepared carbon-nanotube paste electrode by applying square wave voltammetry (SWV). The dE p /dpH value indicated that the oxidation mechanism involved the coupling of H+ with the oxidation process. The peak signals were linearly related to methiocarb concentration in the range of 1.5–59.1 mgL−1 with a detection limit of 0.45 mgL−1. The accuracy and selectivity of the proposed method were shown by calculating the recoveries of methiocarb from soil, river water and pesticide formulation Mesurol®. The calculated percent recoveries for soil and river water samples spiked with 30.0 μg g−1 and 40.0 μg mL−1 levels were 99.3 ± 1.2 and 98.5 ± 0.3 at 95 % confidence limit, respectively.

The present work describes the development of an analytical method for the determination of methiocarb and its degradation products (methiocarb sulfoxide and methiocarb sulfone) in banana samples, using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure followed by liquid chromatography coupled to photodiode array detector (LC-PAD). Calibration curves were linear in the range of 0.5-10 mg L⁻¹ for all compounds studied. The average recoveries, measured at 0.1 mg kg⁻¹ wet weight, were 92.0 (RSD = 1.8%, n = 3), 84.0 (RSD = 3.9%, n = 3), and 95.2% (RSD = 1.9%, n = 3) for methiocarb sulfoxide, methiocarb sulfone, and methiocarb, respectively. Banana samples treated with methiocarb were collected from an experimental field. The developed method was applied to the analysis of 24 samples (peel and pulp) and to 5 banana pulp samples. Generally, the highest levels were found for methiocarb sulfoxide and methiocarb. Methiocarb sulfone levels were below the limit of quantification, except in one sample (not detected).

The use of fungal bioaugmentation represents a promising way to improve the performance of biomixtures for the elimination of pesticides. The ligninolyitc fungus Trametes versicolor was employed for the removal of three carbamates (aldicarb, ALD; methomyl, MTM; and methiocarb, MTC) in defined liquid medium; in this matrix ALD and MTM showed similar half-lives (14d), nonetheless MTC exhibited a faster removal, with a half-life of 6.5d. Then the fungus was employed in the bioaugmentation of an optimized biomixture to remove the aforementioned carbamates plus carbofuran (CFN). Bioaugmented and non-bioaugmented systems removed over 99% ALD and MTM after 8d of treatment, nonetheless a slight initial delay in the removal was observed in the bioaugmented biomixtures (removal after 3d: ALD 87%/97%; MTM 86%/99%, in bioaugmented/non-bioaugmented systems). The elimination of the other carbamates was slower, but independent of the presence of the fungus: >98% for MTM after 35d and >99.5% for CFN after 22d. Though the bioaugmentation did not improve the removal capacity of the biomixture, it favored a lower production of transformation products at the first stages of the treatment, and in both cases, a marked decrease in the toxicity of the matrix was swiftly achieved along the process (from 435 to 448 TU to values

Pesticide pollution in natural waters as a result of intensive agriculture and horticulture has a negative impact on humans and nature. New, cost effective analytical methods are under intense development for continuous monitoring of natural waters and on-field sample screening to meet future analysis needs. In this work the use of chemical sensor array technology based on phthalocyanine coated quartz crystal microbalance sensors is evaluated for direct pesticide analysis in aqueous samples for the first time. For this purpose the phthalocyanine core structure was chemically modified to increase sensor sensitivity and create sensors with widely diverging analyte responses. The obtained sensors show high sensitivities and pesticides detection limits down to 0.03 mg l−1 for common organophosphorus and organonitrogen pesticides such as fenthion and methiocarb. An array composed of selected sensors coated with materials having high variations in their sorption properties is shown to have substantial discrimination capabilities for the identification of various pesticides dissolved in water. Thus, QCM based sensor arrays are considered a promising platform for the direct analysis of aqueous samples.

The objective of the study was to determine the carbon footprint for four farming and marketing systems, using primary data obtained on the farms for autumn pumpkin as an example and model crop. Area for the crop cultivation and weight, i.e. kilogram of saleable product, for the marketing phase were employed as the two functional units with system boundaries from seed acquisition to pumpkin disposal; offset was not used. In the farm carbon footprint (FCF), pumpkins from the organic farm with 240 kg CO 2 eq/ha scored best due to the lowest (50 kg N/ha) (organic) nitrogen application compared with twice that value (448 kg CO 2 eq/ha) for the IP farm. This was due to nitrous oxide emissions, as a consequence of N fertiliser, with 75–99% of FCF in the cultivation phase; it contributed ca. 10% and plant protection (methiocarb in the ‘integrated production’; IP) The large specialised farm showed the best product carbon footprint with 139 g CO 2 eq/kg pumpkin due to use of potassium fertiliser and 3-fold larger yields (18 t/ha versus 5.8 t/ha in the organic [716 g CO 2 eq/kg]) and, to a lesser extent, the scale of the farm business. On the other two farms, cultivation is more extensive with the main income not from pumpkin; any increase in farm size or their pumpkin acreage would not improve their efficacy and product carbon footprint. The imported organic Argentinean pumpkin scored second best with 243 g CO 2 eq/kg despite the long-distance transport due the lower energy consumption of bulk sea freight. The private consumer shopping distance in both cases (retail versus farm shop) amounted to as much as ca. 89% of the product carbon footprint. For a cleaner production, carbon reduction potential appears in improving the potassium fertilisation in all farming systems, except for the large farm, and consumer behaviour regarding the means of transport for shopping. A simple water footprint assessment, based on irrigation and produce washing, resulted in 0.4 (IP), 0.9 L (organic) to 9 L (large scale) blue water/kg pumpkin.