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In this paper, reaction kinetics, degradation mechanisms and associated toxicity have been assessed in detail concerning the abatement of neonicotinoid insecticide clothianidin (CLO) by ozone-based oxidation in water. The second-order rate constants for the reaction of CLO with molecular ozone (O3) and hydroxyl radical ([rad]OH) were determined by the direct and competition kinetics (with UV/H2O2 system as the radical source) methods, respectively, and estimated to be 103 M−1 s−1 and 3.7·109 M−1 s−1. This suggested a (potential) higher contribution of the indirect mechanism rather than the direct degradative pathway in the CLO ozonation process. Additionally, CLO oxidation was studied through an O3 and O3/H2O2 system for three complex real water matrices with distinct characteristics. DOC content was found to be the main parameter responsible for making difficult the achievement of high CLO degradations, whereas carbonate alkalinity did not exert a great impact on the process efficiency. Results indicated that typical ozone doses (up to 1 mg O3/mg DOC) were not enough for the complete removal of this micropollutant, ranging only from 50 to 80%. The study concerning the transformation products (TPs), performed by means of high-resolution mass spectrometry, allowed to suggest potential degradation routes based on the five major CLO-TPs identified. It was inferred that [rad]OH was involved in the formation of all TPs, whereas O3 was only involved in the formation of two of them. A preliminary toxicity assessment concerning CLO and its TPs during ozonation was conducted at three different trophic levels via the ECOSAR software. Results showed that none of the compounds was classified as very toxic for aquatic organisms, and all TPs exhibited minor toxicity than the parent compound. Changes in molecular structure, such as chlorothiazole ring breakdown, could be the main reason for this considerable decrease in toxicity. Overall, the present study demonstrates that ozonation can be considered a suitable technology alternative for CLO (and associated toxicity) abatement from aqueous matrices., This work was financially supported by MCIN/AEI/10.13039/501100011033, with the project PID2020-112674RB-I00, as well as by the Agency for Management of University and Research Grants of the Government of Catalonia (project 2017SGR131).

Plasma activated water (PAW) generated from pinhole plasma jet using gas mixtures of argon (Ar) and 2% oxygen (O2) was evaluated for pesticide degradation and microorganism decontamination (i.e., Escherichia coli and Colletotrichum gloeosporioides) in chili (Capsicum annuum L.). A flow rate of 10 L/min produced the highest concentration of hydrogen peroxide (H2O2) at 369 mg/L. Results showed that PAW treatment for 30 min and 60 min effectively degrades carbendazim and chlorpyrifos by about 57% and 54% in solution, respectively. In chili, carbendazim and chlorpyrifos were also decreased, to a major extent, by 80% and 65% after PAW treatment for 30 min and 60 min, respectively. E. coli populations were reduced by 1.18 Log CFU/mL and 2.8 Log CFU/g with PAW treatment for 60 min in suspension and chili, respectively. Moreover, 100% of inhibition of fungal spore germination was achieved with PAW treatment. Additionally, PAW treatment demonstrated significantly higher efficiency (p < 0.05) in controlling Anthracnose in chili by about 83% compared to other treatments.

The alfalfa weevil Hypera postica (Gyllenhal) (Coleoptera: Curculionidae) is a major pest of alfalfa worldwide. In Spain, insecticide sprayings are mainly used for control with low efficacy. As a potential more sustainable control method, we determined the effectiveness of an alfalfa winter cutting for reducing pest populations in the spring and its interaction with parasitism rate due to Bathyplectes spp. (Hymenoptera: Ichneumonidae). Forty-two commercial fields were split in two parts and one was mowed during winter. Larval abundance in each part of the field was sampled by sweep netting in 2019 and 2020 before the first alfalfa spring cutting, when damage is caused. The rates of parasitism due to Bathyplectes anura (Thomson) and Bathyplectes curculionis (Thomson) were estimated by rearing larvae in the laboratory. Winter cutting significantly reduced the spring larval weevil populations and favored the rate of larval parasitism. Our results suggest that winter cutting can be a useful cultural method for alfalfa weevil control that has potential to be a component of an integrated pest management program. This study was funded by Ministerio de Ciencia, Innovación y Universidades, Spanish Government. Project AGL2017-84127-R

Multielement isotope fractionation studies to assess pollutant transformation are well-established for point-source pollution but are only emerging for diffuse pollution by micropollutants like pesticides. Specifically, chlorine isotope fractionation is hardly explored but promising, because many pesticides contain only few chlorine atoms so that "undiluted" position-specific Cl isotope effects can be expected in compound-average data. This study explored combined Cl, N, and C isotope fractionation to sensitively detect biotic and abiotic transformation of the widespread herbicides and groundwater contaminants acetochlor, metolachlor, and atrazine. For chloroacetanilides, abiotic hydrolysis pathways studied under acidic, neutral, and alkaline conditions as well as biodegradation in two soils resulted in pronounced Cl isotope fractionation (εCl from -5.0 ± 2.3 to -6.5 ± 0.7‰). The characteristic dual C-Cl isotope fractionation patterns (ΛC-Cl from 0.39 ± 0.15 to 0.67 ± 0.08) reveal that Cl isotope analysis provides a robust indicator of chloroacetanilide degradation. For atrazine, distinct ΛC-Cl values were observed for abiotic hydrolysis (7.4 ± 1.9) compared to previous reports for biotic hydrolysis and oxidative dealkylation (1.7 ± 0.9 and 0.6 ± 0.1, respectively). The 3D isotope approach allowed differentiating transformations that would not be distinguishable based on C and N isotope data alone. This first data set on Cl isotope fractionation in chloroacetanilides, together with new data in atrazine degradation, highlights the potential of using compound-specific chlorine isotope analysis for studying in situ pesticide degradation.

Background: The management of empty pesticide containers (EPC) in Bolivia has been recently promoted as a control strategy for dispersed pollution in surface and underground water bodies, as well as in soil. It comprises the rinsing and proper disposal or reuse of clean EPC. However, the rinsing transfers the hazard to water, which must be properly treated before being discharged. Methods: In this study, solar photo-Fenton at low Fe2+ doses were tested at pilot plant scale in Cochabamba (Bolivia) for the removal of pesticides dimethoate and atrazine in their commercial form, spiked in river water. Results: The results demonstrated that solar photo-Fenton ([H2O2]0 = 200 mg L-1) with Fe2+ concentrations between 0.5 and 1.5 mg L-1 is an effective method to remove dimethoate and atrazine, at an initial concentration of 10 mg L-1 each. Efficiency increased when increasing Fe2+ doses, achieving a removal over 99% of both pesticides after a solar irradiation period of 60 minutes (corresponding to an accumulated energy of 4.96 kJ L-1). Conclusions: The presence of high concentrations of natural components of river water, mainly organic and inorganic carbon species, would have contributed to hydroxyl radical scavenging, explaining, together with the low iron dose applied, the high energy (irradiation time) and high hydrogen peroxide concentration required to produce pesticide depletion. Additionally, the relatively low oxidant consumption and mineralization observed leave room for process optimization regarding oxidant and catalyst doses and warrant further studies on its coupling with biological or other post-treatments for the removal of transformation products.

© 2021 by the authors., Background: Pesticide residues are a threat to the health of the global population, not only to farmers, applicators, and other pesticide professionals. Humans are exposed through various routes such as food, skin, and inhalation. This study summarizes the different methods to assess and/or estimate human exposure to pesticide residues of the global population. Methods: A systematic search was carried out on Scopus and web of science databases of studies on human exposure to pesticide residues since 2019. Results: The methods to estimate human health risk can be categorized as direct (determining the exposure through specific biomarkers in human matrices) or indirect (determining the levels in the environment and food and estimating the occurrence). The role that analytical techniques play was analyzed. In both cases, the application of generic solvent extraction and solid-phase extraction (SPE) clean-up, followed by liquid or gas chromatography coupled to mass spectrometry, is decisive. Advances within the analytical techniques have played an unquestionable role. Conclusions: All these studies have contributed to an important advance in the knowledge of analytical techniques for the detection of pesticide levels and the subsequent assessment of nonoccupational human exposure., This research was funded by Ministerio de Ciencia e Innovación and European Regional Development Fund (ERDF), grant number RTI2018-097158-B-C31, and Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital, Generalitat Valenciana (Prometeo 2018/155). D.S. also acknowledges the Generalitat Valenciana for his Santiago Grisolia grant, “GRISOLIAP/2018/102”

Aquest TFG estudia la descontaminació d’aqüífers que contenen nitrat i pesticides. Els dos tipus de descontaminacions que s’estudien són la reducció del nitrat per mètodes biològics i per mètodes químics utilitzant nanopartícules de ferro (nZVI). També s’estudia la seva combinació. Primer es fa una introducció del problema de la contaminació dels aqüífers i una explicació del procés de descontaminació que s’estudia en el treball. Els experiments consten de 5 columnes (reactors de flux continu) que intenten simular les condicions reals d’un aqüífer. Mateix sòl, mateixa aigua, condicions anaeròbiques i sense lluminositat. La única condició que no es recrea és la temperatura. En el procés biològic s’estudia si funciona amb les condicions naturals de l’aqüífer, o bé afegint-li acetat per donar electrons als bacteris i/o inòcul (concentrat de bacteris procedent de la depuradora d’aigües residuals) per si el sòl no té els bacteris necessaris per reduir el nitrat. En el procés químic s’injecta nZVI a les columnes amb una concentració de 3g/L durant unes hores. Les nZVI usades contenen un polímer anomenat “Tween” per evitar que s’aglomerin. S’han utilitzat aquestes perquè són les que han tingut un millor resultat en un TFG previ fet amb experiments de tipus batch (reactors discontinus) on s’han provat diferents tipus de nZVI. Al final es comparen els dos mètodes i es decideix quin ha funcionat millor amb els resultats obtinguts. Pel que fa els pesticides l’estudi és molt menys exhaustiu. Es prova la descontaminació de tres pesticides típics en aqüífers contaminats. El Lindà, el Cloropirifós i el Dieldrín. Pel Cloropirifós no s’obtenen resultats. El TFG estudia la descontaminación de acuíferos que contienen nitrato i pesticidas. Los dos tipos de descontaminaciones que se estudian son la reducción del nitrato por métodos biológicos i por métodos químicos utilizando nanopartículas de Hierro (nZVI). También se estudia su combinación. Primero se hace una introducción del problema de la contaminación de los acuíferos i una explicación del proceso de descontaminación. Los experimentos constan de 5 columnas (reactores de flujo continuo) que intentan simulan las condiciones reales de un acuífero. Mismo suelo, misma agua, condiciones anaeróbicas i sin luminosidad. La única condición que no se recrea es la temperatura. En el proceso biológico se estudia si funciona en las condiciones naturales del acuífero y/o añadiendo acetato para donar electrones a las bacterias y/o inoculo (concentrado de bacterias procedente de la depuradora de aguas residuales) por si el suelo contiene o no las bacterias necesarias para reducir el nitrato. En el proceso químico se inyectan nZVI a las columnas con una concentración de 3g/L durante unas horas. Las nZVI usadas contienen un polímero nombrado “Tween” para evitar la aglomeración. Se han utilizado éstas porque fueron las que tuvieron un mejor resultado en un TFG previo hecho con experimentos de tipo Bach (reactores discontinuos) donde se han probado diferentes tipos de nZVI. Al final se comparan los dos métodos i se decide cual ha funcionado mejor con los resultados obtenidos. Para los pesticidas el estudio es menos exhaustivo. Se prueba la descontaminación de tres pesticidas típicos en acuíferos contaminados. El Lindano, el Cloropirifós y el Dieldrín. Para el Cloropirifós no se obtienen resultados. This TFG studies the decontamination of aquifers that contains nitrate and pesticides. Decontamination by biological methods as well as decontamination by chemical methods using nano zero-valent iron (nZVI) are studied here. This work also analyses their combination. First, we have an introduction of to the problem of the contamination of aquifers and an explanation of the process of decontamination that is under study on this TFG. The experiments consist of 5 columns (reactors of continuous flow) that try to simulate the conditions of a real aquifer. Same soil, same water, anaerobic conditions, and with no light. The only one condition that is not recreated is the temperature. In the biological process, it studies if it works with the natural aquifer conditions or adding acetate for donating electrons to the bacteria and/or inoculum (concentrated bacteria that comes from a water treatment plant) in case of soil doesn’t contain the bacteria needed to reduce nitrate. In the chemical process, it’s injected nZVI to the columns with a concentration of 3g/L during a few hours. The nZVI used contains a polymer named “Tween” for avoiding agglomeration. It is been used because it has been the best on another previous TFG done with bach experiments (discontinuous reactors) where some other types of nZVI have been tested. In the end, both methods are compared and it is decided which one is the best based on the results. For the pesticides, the study is less exhaustive. The decontamination of three of the typical pesticides in contaminated aquifers is tested. The Lindane, Chlorpyrifos and Dieldrin. For Chlorpyrifos there are no results at the end. Objectius de Desenvolupament Sostenible::6 - Aigua Neta i Sanejament

Memoria presentada para optar al título de Doctora por la Universidad de Barcelona.-- Tutor académico: Dr. Francisco Javier Santos Vicente., [EN] The assessment of pesticide occurrence in different environmental compartments has become a matter of outstanding importance since its effects on exposed organisms may be considered a warning on the potential risk these substances may pose to human health. In this context, and in the framework of this doctoral thesis, the presence and fate of 52 pesticides and transformation products were evaluated in surface water, groundwater, and sediments from four river basins, and the associated environmental risk was assessed. In addition, the performance of a fungi-based bioremediation technique for the removal of pesticides was evaluated. The methods developed are based on the use of advanced extraction techniques such as on-line solid-phase extraction, pressurized liquid extraction, and QuEChERS extraction, and analyte determination with liquid chromatography coupled to tandem mass spectrometry. The use of an isotope-dilution approach ensured the reliability of the results and the satisfactory performance of the methodologies in terms of accuracy, precision, linearity, sensitivity and matrix effect. The most relevant pesticides detected in agricultural areas (Ebro River Delta, Ter River) were the herbicides widely used in rice cultivation bentazone, MCPA and propanil, while in urban and industrial areas like the lower Llobregat River basin, the most relevant pesticides were bromoxynil, diuron, linuron and terbutryn, used for both agricultural and non-agricultural purposes. In the sediments of the Llobregat River and the fish samples collected from the Adige River, most of the pesticides found are currently banned, which suggest their persistence in the environment. The assessment of the environmental risk highlighted the role of pesticides as relevant stressors in the aquatic environment. The degradation of selected pesticides by the fungus T. versicolor point at this organism as an efficient, green and economic alternative for pesticide removal during water treatment. Further pesticide pollution attenuation was attempted by contributing to the design of participatory multi-actor events to increase the awareness of farmers and stakeholders on the issue of environmental pollution by pesticides, involving them in the decision-making processes for the implementation of mitigation measures and best management practices aimed at reducing pesticide release into the environment., [ES] La evaluación de la presencia de plaguicidas en los diferentes compartimentos ambientales es de gran importancia ya que sus efectos en los organismos expuestos pueden considerarse una advertencia del riesgo potencial que estas sustancias pueden suponer para la salud humana. En este contexto, en el marco de esta tesis doctoral se ha estudiado la presencia y destino de 52 pesticidas y productos de transformación en aguas superficiales, subterráneas, sedimentos y biota de cuatro cuencas hidrográficas, y se ha evaluado el riesgo ambiental asociado. Además, se ha valorado la eficacia de una técnica de biorremediación basada en hongos para eliminar plaguicidas seleccionados. Los métodos desarrollados se basan en el uso de técnicas avanzadas de extracción como son la extracción en fase sólida (SPE) on line automatizada, la extracción mediante líquidos presurizados (PLE) seguida de purificación del extracto mediante SPE, y la extracción con QuEChERS para la preconcentración de los plaguicidas en agua, sedimento, y biota, respectivamente, y la determinación de los compuestos mediante cromatografía de líquidos acoplada a espectrometría de masas en tándem. El uso de dilución isotópica para la cuantificación garantiza la fiabilidad de los resultados y el rendimiento satisfactorio de los métodos desarrollados en términos de exactitud, precisión, linealidad y efecto de la matriz. La sensibilidad de los métodos desarrollados posibilita la evaluación de los plaguicidas seleccionados a los niveles de los estándares de calidad ambiental marcados por la Comisión Europea en el ámbito de la política de aguas. Los plaguicidas más relevantes detectados en las áreas agrícolas investigadas fueron los herbicidas bentazona, MCPA y propanil, ampliamente utilizados en el cultivo del arroz en el delta del río Ebro. El río Ter, también afectado por actividades agrícolas intensivas, resultó contaminado en menor medida por bentazona y MCPA. En áreas urbanas e industriales como la cuenca baja del río Llobregat, los compuestos más ubicuos y abundantes fueron bromoxinilo, diurón, linurón y terbutrina, utilizados tanto con fines agrícolas como no agrícolas. En esta zona, muchos de los plaguicidas encontrados superaban el límite de 100 ng/L establecido por la Unión Europea para plaguicidas individuales en aguas destinadas al consumo humano. En los sedimentos del río Llobregat y las muestras de peces recogidas en el río Adige, los plaguicidas presentan propiedades físico-químicas que los hacen más propensos a acumularse en sedimentos o bioacumularse en la biota. La mayoría de los pesticidas detectados en estas matrices están actualmente prohibidos, lo cual sugiere su persistencia en el medio ambiente. Diclorvos e irgarol superaron las concentraciones máximas admisibles establecidas por la Comunidad Europea como normas de calidad ambiental para compuestos prioritarios en aguas superficiales, mientras que los límites máximos aceptables de detección (LODs) establecidos en la Lista de Observación europea fueron superados por acetamiprid, imidacloprid, tiacloprid y metiocarb. La evaluación del riesgo ambiental ha destacado el papel de los plaguicidas como estresores relevantes en el medio acuático. Además, la co-ocurrencia de plaguicidas resulta en un aumento del riesgo en los diversos compartimentos ambientales estudiados, lo que hace necesaria la adopción de medidas para atenuar la contaminación ambiental por plaguicidas. Con este propósito, se exploró la capacidad del hongo T. versicolor para degradar malatión, acetamiprid e imidacloprid. Los resultados apuntan a este organismo como una alternativa eficaz, ecológica y económica para la eliminación de pesticidas del agua. Por otro lado, se diseñaron eventos participativos con el fin de aumentar la conciencia de los agricultores y otras partes interesadas sobre el problema de la contaminación ambiental por plaguicidas, involucrándolos en los procesos de toma de decisiones para motivar la implementación de medidas de mitigación destinadas a reducir la liberación de plaguicidas al medio ambiente., This PhD thesis has been financially supported by the European Union through the research projects WaterProtect (Horizon 2020 - Research and Innovation Framework Programme, No. 727450), GLOBAQUA (Seventh Framework Programme (FP7), No. 265264), and SOLUTIONS (FP7, No. 603437), and by the Ministry of Economy and Competitiveness (MINECO) through the BECAS project (Spanish State Research Agency and European Regional Development Fund (ERDF), CTM2016-75587-C2-2-R). The work conducted within this thesis has been also partially funded by the Government of Catalonia (2017 SGR 01404 and SGR 00014) and the Spanish Ministry of Science and Innovation (Project CEX2018-000794).

Groundwater is one of the main freshwater resources on Earth, but its contamination with NO3− and pesticides jeopardizes its viability as a source of drinking water. In this work, a detailed study of single electro-oxidation (EO) and electrodenitrification and paired EO/electrodenitrification processes has been undertaken with simulated and actual groundwater matrices containing 100 mg dm−3 NO3− and/or 5 mg dm−3 terbuthylazine pesticide. Galvanostatic electrolyses were made with 500 cm3 of solutions at pH 4.0-10.5 and 250-1000 mA in tank reactors with a RuO2 or boron-doped diamond (BDD) anode and one or two Fe cathodes, all of them in the form of meshes. Most of NO3− removals agreed with a pseudo-first-order kinetics. In Cl−-free media, NH4+ predominated as electroreduction product. In chloride media, a greater amount of N-volatiles was determined alongside a slower electrodenitrification, especially with RuO2 due to the partial re-oxidation of electroreduction products like NH4+ by active chlorine. The pesticide decays were also fitted to a pseudo-first order kinetics, and its presence led to a smaller release of N-volatiles. Overall, BDD always favored the pesticide degradation thanks to the action of BDD( • OH), whereas RuO2 was preferred for electrodenitrification under some conditions. The EO/electrodenitrification of groundwater was successful once the matrix was softened to minimize its hardness. The NO3− concentration was reduced below the limit established by the WHO. Overall, the BDD/Fe cell was more suitable than the RuO2/Fe cell because it accelerated the pesticide removal with a simultaneous high degree of NO3− electroreduction. However, it produced toxic chlorate and perchlorate. A final post-treatment with an anion exchange resin ensured a significant removal of both ions, thus increasing the viability of the electrochemical approach to treat this type of water. Chromatographic analyses revealed the formation of ten heteroaromatic products like desethyl-terbuthylazine and cyanuric acid, alongside oxalic and oxamic as final short-chain carboxylic acids.

[eng] This thesis has been developed in the framework of the European FoodSmartphone project with the objective to develop user-friendly smartphone-connected electrochemical immunosensors for pesticide residue detection in different food matrices. The target pesticides selected were atrazine, paraquat, bromopropylate and chlorpyrifos, based on their significant impact in the field of food safety. In order to achieve this objective, first the performance of the immunoreagents necessary for the detection of the selected target pesticides (atrazine, chlorpyrifos, bromopropylate and paraquat) was evaluated by Enzyme-linked immunosorbent assays (ELISA). Afterwards, several different typologies of carbon-based screen printed electrodes (SPEs) were produced, modified and characterized. The modification of the electrodes was carried out with the nanomaterial carbon black and the electrode with the best electrochemical properties was used as a platform for the development of different electrochemical immunosensors. The direct use of the SPE’s surface was proven to be successful in the detection of the herbicide atrazine in buffer and in orange juice, achieving limit of detection (LOD) values of 2.09 (0.45 µg L-1) and 2.47 nM (0.53 µg L-1) respectively. An electrochemical immunosensor was also developed for the detection of the insecticide chlorpyrifos in wheat flour samples achieving LOD values around 5 µg kg-1. The feasibility of the developed sensor as a screening method for food safety monitoring was confirmed by the analysis of real samples and their validation by ELISA and a chromatographic reference method (GC-MS). Furthermore, electrochemical immunosensors were developed in buffer for the detection of the pesticides paraquat and bromopropylate, achieving LOD values of 0.24 µg L-1 and 4.32 µg L-1 respectively. All of the achieved LOD values were well below the maximum residue limits (MRLs) established by the European Commission. Finally, the multiplexation capabilities of the developed individual immunosensors were demonstrated with a proof-of-concept study of a smartphone-connected multiplexed sensor. The developed sensor has the potential to be integrated in an easy-to-use and affordable device, which could be used by farmers and inspectors (e.g. at borders) for at-line measurements in order to ensure food safety and quality in the coming years.

We study the effects of aerial fumigation of banana plantations on newborns’ birth weight during the period 2015-2017 in Ecuador. We use mothers’ addresses and information on the perimeter of the plantations to create an individual measure of newborns’ exposure to pesticides. We use this measure to implement three independent identification strategies to address the endogeneity of exposure to aerial fumigations. First, we consider a difference-in-differences strategy that exploits seasonal variations in the use of pesticides across provinces. Second, we estimate a difference-in-differences model that considers geographical variations in the use of pesticides across comparable crops. Third, and finally, we estimate a maternal fixed effects model to examine the effect of pesticides on siblings who had a different residence during gestation and who were exposed to different levels of fumigations. Our first empirical model shows that newborns exposed to pesticides, when their first gestational trimester coincides with the periods of intensive fumigations of the plantations, have a birth weight reduction of between 38 and 89 grams. Moreover, exposure to pesticides increases the likelihood of low birth weight and low Apgar score at the first minute by around 0.35 and 0.33, respectively. The second model finds that newborns exposed to fumigated banana plantations have a birth weight deficit of between 29 and 76 grams, when compared to those exposed to other fumigated crops. Finally, the maternal fixed effect model shows that girl newborns exposed to pesticides have a birth weight deficit of 346 grams when compared to non-exposed siblings.

© 2021 The Authors., One of the aspects considered about the presence of contaminants in the aquatic ecosystems is their possible effect on critically endangered species, as the case of European eel, Anguilla anguilla. However, there is a lack of analytical methods to determine these contaminants due to the complexity of eel matrix (contains 5–20 % of lipids and 5–15 % of proteins). Thus, a multi-residue method using QuEChERS extraction a clean-up based on new specific sorbents (to eliminate lipids) and liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to determine a mix of 21 contaminants. Compared to the previously reported methods (Degani et al., 1986), which were developed for mussels, in this study, one of the proposed extraction methods were adapted to different fish tissues of higher complexity, such as liver and muscle of A. anguilla. The effectivity of dispersive solid phase extraction (dSPE) using new specific Enhanced Matrix Removal (EMR-lipid) as clean-up for lipid removal was tested. Clean extracts of matrices with high protein (5–15 %) and lipid (5–20 %) content were obtained ensuring robustness and durability of the analytical systems. Emerging contaminants extractable by this procedure comprise four different families (pesticides, perfluoroalkyl substances (PFASs), pharmaceuticals and drugs of abuse). Then, it could be further applied to wide scope screening strategies., The research that led to these results received funding from the Spanish Ministry of Science, Innovation and Universities and the ERDF (European Regional Development Fund) through the project WETANDPAC (RTI2018-097158-B-C31) and from the Generalitat Valenciana through the project ANTROPOCEN@ (PROMETEO/2018/155). R. Álvarez-Ruiz acknowledges the Spanish Ministry of Science, Innovation and Universities and the ERDF for his FPI grant BES-2016-078612.

Assessment and management of issues related to pesticide residues, such as environmental fate, monitoring and toxicity, are complex and, in many cases, require costly studies. The early establishment of a priority list of pesticides that should be monitored and assigned to a restricted-use policy is an important issue of post-registration Risk Assessment (RA). Various pesticide registration approaches have been adopted by different countries with those from Europe and the USA being the most popular, constituting the major prototypes for registration approaches in other countries. Adoption of pesticide registration and monitoring systems developed in Europe or USA by Latin American and Caribbean countries may underestimate factors affecting the environmental fate and toxicity of pesticides in their own countries. Incentive for this short review was the activities undertaken during the three KNOWPEC workshops held in Costa Rica, Argentina and Bolivia where European pesticide experts met Latin American experience in the form of Costa Rica's exceptional environmental conditions and ecology, Argentina's and Uruguay's soyisation and Bolivia's contrasting climate and agricultural zones. During the parallel activities of the workshop - including scientific presentations, field trips, interviews and meetings among European partners and pesticide stakeholders in Latin America, - the whole pesticide chain (import-export, trade, application, plant protection-efficacy, residues, monitoring, remediation and risk) was studied and clarified. Recently-published chemical prioritization studies were reviewed to consider their use as a tool to support risk assessments. Differences in regional practices are highlighted as regards to the establishment of RA or prioritization strategy in European and Latin American regimes. General guidance of establishing a cost-effective pesticide monitoring scheme in water bodies of Latin America and the Caribbean (LAC) is also proposed. Moreover, we summarize the most important factors that should be taken into consideration for prioritization approaches and categorization used in pesticide environmental monitoring studies. Consideration of current RA approaches and limitations, and pesticide prioritization exercises highlighted in this Commentary could assist in the management of pesticides in Latin America and Caribbean.

Although many different designed air-assisted sprayers can be used for pesticide application in apple orchards, the lack of adequate adjustments according to specific crop characteristics leads to application inefficiencies and failures. To evaluate the spray coverage and biological efficacy of different application techniques combined with an alternative dosage adjustment based on tree row volume (TRV), field tests with five different techniques were carried out at three crop stages on a commercial apple orchard. The results showed that conventional mist-blower with a high application volume (800 L ha-1) exhibited an excessive coverage with a high risk of contamination at the early crop stage (BBCH19), whereas other treatments using different application techniques, with a reduced volume rate and pesticide dose of 75%, were equivalent with good uniformity, revealing the great importance of suitable adjustment for the sprayers. For the middle and late stages (BBCH64 and 75), the orchard sprayer equipped with vertical booms provided the maximum coverage, and the pneumatic sprayer achieved significantly higher impacts density, which revealed their advantages and high efficiency for dense apple trees. The newly developed multi-fan sprayer and pneumatic sprayer achieved consistent coverage during the entire crop stage, independent of the changes in canopy structure (TRV). This indicates that a suitable setting and adjustment of the sprayer can contribute to a consistent spray quality. In general, benefiting from these new spraying technologies, an average reduction of 60.7% in pesticide dose and volume rate were achieved within the entire season, maintaining the same threshold of pest and disease control as that of the higher reference dose normally applied. These results demonstrate the importance of an alternative dose adjustment method to meet the requirements of the Farm to Fork strategy.

Agricultural productivity cannot be sustained without the application of plant protection measures. Within the framework of integrated pest management (IPM), the use of chemical pesticides should be limited to the last option among the available practices. Even though their use remains common, it carries associated environmental and human health risks. One of the most accepted practices within IPM is the reduction of spraying events and/or pesticide applied doses. DOSA3D is a decision support system that allows the dose to be adjusted to the specific treatment scenario. For this, DOSA3D calculates the optimal application volume rate by estimating the leaf area index and takes into account the overall spraying efficiency and the pest or disease to be controlled. The system adopts specific minimum volume rates for fruit trees and vineyards without compromising the crop health status. To establish the adjusted dose, the labeled or the adviser prescription concentration is kept. Resulting adjusted doses provided by DOSA3D achieved pesticide savings up to 53% in fruit trees and 60% in vineyards. DOSA3D has been validated against the main diseases and pests of fruit trees and vineyards: brown spot and psylla in pear orchards; alternaria blotch disease, apple scab, codling moth, oriental moth and red spider mite in apple orchards; powdery mildew, brown rot, aphids, thrips and mites in peach orchards; and, powdery mildew, yellow spider mite and leafhoppers in grapevine orchards. In addition, a methodology called Green Way is presented to provide consistent and crop safety pesticide doses when these are labeled as concentration or ground area doses. his study wasfinanced by the EU Horizon 2020 project EUCLID[grant number 633999], the Spanish Ministry of Economy and Compet-itiveness project AgVance [AGL2013-48297-C2-2-R] and the SpanishMinistry of Agriculture, Fisheries and Food project GOPHYTOVID [con-tract 2018002001192]. We are also grateful for funding by theSecretaria d'Universitats i Recerca del Departament d'Empresa iConeixement de la Generalitat de Catalunya under Grant 2017 SGR 646

CoS2/MWCNTs have been previously described as potentially viable catalysts to enhance the classical two-electron H2O2 production from O2 reduction reaction (ORR) for in situ water treatment, but their poor stability still limits their large-scale application. Here, the synthesis and characterization of a novel electrocatalyst made of CoSP nanoparticles supported onto multi-walled carbon nanotubes (MWCNTs) is reported. X-ray diffraction data demonstrated the much higher stability conferred upon partial sulfur substitution by phosphorus. Linear and cyclic voltammograms of CoSP/MWCNTs showed a potential window from 0.9 to 0.1 V for the ORR at pH 3.0, along with greater H2O2 production ability. Large area air-diffusion cathodes were manufactured by depositing the catalyst onto carbon paper, being further used in a pre-pilot filter-press cell containing a boron-doped diamond anode. A stable H2O2 accumulation, with maximum current efficiency of 72.0%, was found upon electrolysis of 2.5 L of 0.050 M Na2SO4 at pH 3.0 and 25 mA cm−2. As a crucial finding, Co leaching was negligible. Solutions with 20 mg L−1 of the herbicide bentazon in the same electrolyte could not be mineralized by electrochemical oxidation, whereas photoelectro-Fenton with an UVA lamp and 0.50 mM Fe2+ led to total removal of the herbicide with 77.0% mineralization.

The implementation of Integrated Pest Management (IPM) in current agricultural practice is a convenient and very effective strategy to maintain pest populations under control. The use of Biological Control Agents, like Phytoseiulus persimilis, is key for the success of such approach. This predatory mite is widely used since it is very effective for controlling the two spotted spider mite (Tetranychus urticae), one of the most devastating pests worldwide. Here we show the identification of mutations located in the Voltage Gated Sodium Channel (VGSC) of P. persimilis, that correlate with the reduced susceptibility to deltamethrin observed in commercially sourced colonies of this predatory mite. We have found that the mites from each source have intrinsic genotypic differences that correlate with their phenotype when tested with different concentrations of deltamethrin. Thus, the mites from Syngenta carrying the mutations M918L and A1536T were able to survive up to 10 ppm, while the mites form Koppert with the combination M918L, L925V and S1539T survived the treatment with 40 ppm. These mutations are located in a particular region of the channel, previously proposed as the binding site for this family of pesticides and a hot spot for resistance mutations. The potential implications for optimised integration of P. persimilis within an IPM strategy are discussed.

Background: Prenatal exposure to organophosphate (OP) pesticides associate with impaired neurodevelopment in humans and animal models. However, much uncertainty exists about the brain structural alterations underlying these associations. The objective of this study was to determine whether maternal OP pesticide metabolite concentrations in urine repeatedly measured during gestation are associated with brain morphology and white matter microstructure in 518 preadolescents aged 9-12 years. Method: Data came from 518 mother-child pairs participating in the Generation R Study, a population-based birth cohort from Rotterdam, the Netherlands. Maternal urine concentrations were determined for 6 dialkylphosphates (DAPs) including 3 dimethyl (DM) and 3 diethyl (DE) alkyl phosphate metabolites, collected at early, mid, and late pregnancy. At child's age 9-12 years, magnetic resonance imaging was performed to obtain T1-weighted images for brain volumes and surface-based cortical thickness and cortical surface area, and diffusion tensor imaging was used to measure white matter microstructure through fractional anisotropy (FA) and mean diffusivity (MD). Linear regression models were fit for the averaged prenatal exposure across pregnancy. Results: DM and DE metabolite concentrations were not associated with brain volumes, cortical thickness, and cortical surface area. However, a 10-fold increase in averaged DM metabolite concentrations across pregnancy was associated with lower FA (B = -1.00, 95%CI = -1.80, -0.20) and higher MD (B = 0.13, 95%CI = 0.04, 0.21). Similar associations were observed for DE concentrations. Conclusions: This study provides the first evidence that OP pesticides may alter normal white matter microstructure in children, which could have consequences for normal neurodevelopment. No associations were observed with structural brain morphology, including brain volumes, cortical thickness, and cortical surface area. This research received financial support from the intramural research program of the National Institute of Environmental Health Sciences, National Institutes of Health (Grant# HHSN273201500003C). Neuroimaging was supported by the ZonMw TOP project no. 91211021. Henning Tiemeier was supported by a grant of the Netherlands Organization for Scientific Research (NWO grant No. 024.001.003, Consortium on Individual Development, and NWO/ ZonMW grant 016.VICI.170.200). Mònica Guxens is funded by a Miguel Servet fellowship (MS13/00054, CPII18/00018) awarded by the Spanish Institute of Health Carlos III. Monica Guxens acknowledges support from the Spanish Ministry of Science and Innovation and State Research Agency through the “Centro de Excelencia Severo Ochoa 2019–2023” Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Programme. Dr. Hanan El Marroun was supported by Stichting Volksbond Rotterdam, the Dutch Brain Foundation (De Hersenstichting, project number GH2016.2.01) and the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 733206 LifeCycle)

One of the main challenges of electrochemical Fenton-based processes is the treatment of organic pollutants at near-neutral pH. As a potential approach to this problem, this work addresses the use of a low content of soluble chelated metal catalyst, formed between Fe(III) and ethylenediamine-N,N'-disuccinic (EDDS) acid (1:1), to degrade the herbicide triclopyr in 0.050 M Na2SO4 solutions at pH 7.0 by photoelectro-Fenton with UVA light or sunlight (PEF and SPEF, respectively). Comparison with electro-Fenton treatments revealed the crucial role of the photo-Fenton-like reaction, since this promoted the production of soluble Fe(II) that enhanced the pesticide removal. Hydroxyl radicals formed at the anode surface and in the bulk were the main oxidants. A boron-doped diamond (BDD) anode yielded a greater mineralization than an IrO2-based one, at the expense of reduced cost-effectiveness. The effect of catalyst concentration and current density on the performance of PEF with BDD was examined. The PEF trials in 0.25 mM Na2SO4 + 0.35 mM NaCl medium showed a large influence of generated active chlorine as oxidant, being IrO2 more suitable than RuO2 and BDD. In SPEF with BDD, the higher light intensity from solar photons accelerated the removal of the catalyst and triclopyr, with small effect on mineralization. A plausible route for the herbicide degradation by Fe(III)-EDDS-catalyzed PEF and SPEF is finally proposed based on detected byproducts: three heteroaromatic and four linear N-aliphatic compounds, formamide, and tartronic and oxamic acids.

We aimed to study the association between occupational exposure to pesticides and chronic lymphocytic leukemia (CLL) in Spain. Occupational exposure to pesticides (four insecticides, four herbicides and two fungicides) was evaluated using a job-exposure matrix for the Spanish population (MatEmESp) among 302 CLL cases and 1567 population controls in five regions of Spain, 2010–2013. Cumulative exposure scores (CES) were obtained by summing across the exposed jobs the product of prevalence, intensity and duration of exposure to each active substance. Principal components analysis (PCA) and logistic regression models adjusted for age, sex, region, education and occupational exposure to solvents were used. Around 20% of controls and 29% of cases were exposed to one or more pesticides. Compared to non-exposed, subjects in the highest tertile (3rd tertile) of CES of insecticides, herbicides, fungicides were more likely to have CLL [OR (95% CI), P-trend; 2.10 (1.38; 3.19), 0.002; 1.77 (1.12; 2.80), 0.12; and 1.67 (1.06; 2.64), 0.10, respectively). Following PCA, the first component (PC1, explaining 70% of the variation) equally led by seven active substances (the insecticide pyrethrin, all herbicides, all fungicides) was associated with a 26% higher odds of having CLL for 1-standard deviation increase in PC1 (95% CI: 1.14 to 1.40). These results confirm previous associations between CLL and exposure to pesticides and provide additional evidence by application groups and active substance. However, more research is needed to disentangle independent effects of individual active substances., Spanish Ministry of Economy and Competitiveness-Carlos III Institute of Health, European Union (EU) PI08/1770 PI08/0533 PI08/1359 PS09/00773 PI11/01403 PI11/02213 PI14/1219 PI15/00966 PI17/01280 RTIC RD06/0020/0095 RD12/0036/0036 SV-09-CLINIC-1, Instituto de Salud Carlos III IJCI-2016-29502, Instituto de Salud Carlos III API 10/09, Obra Social CAJASTUR (SV-CAJASTUR-1), La Caixa Foundation 2010ACUP 00310, Secretariat for Universities and Research of the Ministry of Business and Knowledge of the Government of Catalonia 2017SGR1085, Spanish Ministerio de Economia y Competitividad (MINECO) through the Instituto de Salud Carlos III (ISCIII) PMP15/00007, CIBERONC del ISCIII

Pòster Juny

There is increasing concern regarding the potential implications of continuous dietary exposure to low doses of artificial chemical pollutants, particularly in critical life stages such as pregnancy and lactation. Within a wider social research, we analyzed the risk perception, discourses, and attitudes of health professionals regarding dietary exposure to artificial chemical contaminants. Data was collected by personal interviews on 35 health professionals from two Spanish regions. Although the participants’ discourses were strongly dominated by the nutritional composition and microbiological contamination, 34 expressed some concern regarding metals, and 23 regarding pesticides. Although only one participant mentioned a plasticizer (i.e., bisphenol A), we noted an underlying concern, since six professionals admitted to recommending pregnant women to somewhat avoid plastic food containers, and were aware of mother-to-child transmission and accumulation of artificial chemicals. The ubiquity of the exposure, the inability to locate the threat, and contradictory messages can all create a sense of helplessness and subsequent cognitive adjustments. Our participants also reported a lack of information, particularly on emerging pollutants. In conclusion, we found a range of valuable discourses that can aid in orienting public health strategies aimed at health professionals who have a substantial influence on their patients., Spanish Ministerio de Economia, Industria y Competitividad CSO2014-58144-P, Barcelona City Council (Ajuntament de Barcelona) 17S05083-001, Ramon y Cajal program (Ministerio de Economia, Industria y Competitividad, Spain) RYC-2016-20155

10 pages, 5 figures, 1 table supplementary data https://doi.org/10.1016/j.aquatox.2020.105617, In fish, the study of cholinesterases (ChEs) and carboxylesterases (CEs), apart from their involvement in neural activity and xenobiotic metabolism, respectively, requires to be further explored. The European sea bass (Dicentrarchus labrax) was the fish model used to characterise B-esterases in several matrices and organs, as well as to assess the impacts of the insecticide fipronil at two temperatures: the natural temperature at the time of sampling (13 °C) and at 16 °C (based on climate change-related predictions for the Mediterranean region). Fipronil exerts harmful effects in non-target species; however, some countries are reluctant to implement regulations without additional evidence on their toxicity. A comprehensive study was performed in fish pre-acclimated to the two targeted temperatures for 15 days. B-esterases were evaluated in multiple samples after 7 and 14 day exposures to fipronil in feed (dose of 10 mg/kg) and after a 7-day depurative period. Based on hydrolysis rates, results showed that CEs were measurable in all matrices while ChEs were more abundant in muscle and, particularly, acetylcholinesterase (AChE) in the brain. A + 3 °C increase in temperature had little influence on B-esterase activity; however, fipronil caused a significant increase in brain AChE (1.5-fold) and CE (3-fold) activities. Other matrices and organs also experienced alterations in their B-esterase activities that could compromise their physiological functions, This work was financed by the Spanish Ministry of Economy, Industry and Competivity (ref CGL2016-76332-R MINECO/FEDER, UE), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

The exact cause of Parkinson's disease (PD), the second most prevalent neurodegenerative disease in modern societies, is still unknown. Many scientists point out that PD is caused by a complex interaction between different factors. Although the main risk factor is age, there are other influences, genetic and environmental, that individually or in combination may trigger neurodegenerative changes leading to PD. Nowadays, research remains focused on better understanding which environmental factors are related to the risk of developing PD and why. In line with the knowledge on evidence on exposures that prevent/delay PD onset or that impact on disease progression, the aims of this review were: (i) to comment on the non-genetic risk factors that mainly affect idiopathic PD; and (ii) to comment on seemingly reliable preventive interventions. We discuss both environmental factors that may affect the central nervous system (CNS) or the intestinal tract, and the likely mechanisms underlying noxious or protective actions. Knowledge on risk, protective factors, and mechanisms may help to envisage why nigral dopaminergic neurons are so vulnerable in PD and, eventually, to design new strategies for PD prevention and/or anti-PD therapy. This article reviews the variety of the known and suspected environmental factors, such as lifestyle, gut microbiota or pesticide exposition, and distinguishes between those that are harmful or beneficial for the PD acquisition or progression. In fact, the review covers one of the most novel players in the whole picture, and we address the role of microbiota on keeping a healthy CNS and/or on preventing the "side-effects" related to aging.

Compound-specific isotope analysis (CSIA) is a valuable tool for assessing the fate of organic pollutants in the environment. However, the requirement of sufficient analyte mass for precise isotope ratio mass spectrometry combined with prevailing low environmental concentrations currently limits comprehensive applications to many micropollutants. Here, we evaluate the upscaling of solid-phase extraction (SPE) approaches for routine CSIA of herbicides. To cover a wide range of polarity, a SPE method with two sorbents (a hydrophobic hypercrosslinked sorbent and a hydrophilic sorbent) was developed. Extraction conditions, including the nature and volume of the elution solvent, the amount of sorbent and the solution pH, were optimized. Extractions of up to 10 L of agricultural drainage water (corresponding to up to 200000-fold pre-concentration) were successfully performed for precise and sensitive carbon and nitrogen CSIA of the target herbicides atrazine, acetochlor, metolachlor and chloridazon, and metabolites desethylatrazine, desphenylchloridazon and 2,6-dichlorobenzamide in the sub-g L-1-range. C-13/C-12 and N-15/N-14 ratios were measured by gas chromatography-isotope ratio mass spectrometry (GC/IRMS), except for desphenylchloridazon, for which liquid chromatography (LC/IRMS) and derivatization-GC/IRMS were used, respectively. The method validated in this study is an important step towards analyzing isotope ratios of pesticide mixtures in aquatic systems and holds great potential for multi-element CSIA applications to trace pesticide degradation in complex environments.

A gas chromatography-single quadrupole mass spectrometry method was developed and validated for compound-specific chlorine isotope analysis (Cl-CSIA) of three chlorinated herbicides, atrazine, acetochlor, and metolachlor, which are widespread contaminants in the environment. For each compound, the two most abundant ions containing chlorine (202/200 for atrazine, 225/223 for acetochlor, and 240/238 for metolachlor) and a dwell time of 30 ms were determined as optimized MS parameters. A limit of precise isotope analysis for ethyl acetate solutions of 10 mg/L atrazine, 10 mg/L acetochlor, and 5 mg/L metolachlor could be reached with an associated uncertainty between 0.5 and 1 . To this end, samples were measured 10-fold and bracketed with two calibration standards that covered a wide range of δ37Cl values and for which amplitudes matched those of the samples within 20% tolerance. The method was applied to investigate chlorine isotope fractionation during alkaline hydrolysis of metolachlor, which showed a shift in δ37Cl of +46 after 98% degradation, demonstrating that chlorine isotope fractionation could be a sensitive indicator of transformation processes even when limited degradation occurs. This method, combined with large-volume solid-phase extraction (SPE), allowed application of Cl-CSIA to environmentally relevant concentrations of widespread herbicides (i.e., 0.5-5 μg/L in water before extraction). Therefore, the combination of large-volume SPE and Cl-CSIA is a promising tool for assessing the transformation processes of these pollutants in the environment.

An exposure experiment will be carried out in an artificial marine mesocosm (AAM) where mussels will be exposed to a mixture of environmental contaminants at relevant environmental concentrations. Specimens with a uniform size distribution will be used, they will be fed daily during the acclimation and experiment periods. Two aquariums will be used for the exposed groups and two for the controls. All groups will be held in the same conditions except the presence of contaminants that will be exclusively in the exposed groups.

[cat] Durant les dècades dels anys 50 i 60 del segle XX es van utilitzar arreu del món diferents tipus de compostos organoclorats i organobromats, que pertanyen als contaminants orgànics persistents (COPs), com a pesticides, retardants de flama o aïllants tèrmics. El 2001 la Convenció d’Estocolm sobre COPs va reconèixer els efectes adversos d’aquestes compostos sobre la salut i el medi ambient i va proposar controls amb l’objectiu d’eliminar o reduir el seu ús. Com a conseqüència d’aquesta prohibició altres compostos s’han anat sintetitzat per substituir-los, alguns d’ells són els pesticides organofosforats i els piretroides, que tot i que no són persistents el fet que s’utilitzin en grans quantitats fa que siguin un risc pel medi ambient i la salut. Aquest estudi avalua, per una banda, l’abast de diferents contaminants orgànics persistents (COPs), especialment els compostos organoclorats (OCs) i els polibromodifenil èters (PBDEs), en dones. I per altra banda, la càrrega i exposició de diferents pesticides organofosforats i piretroides en població general de tres països europeus, dos països on l’agricultura esta molt present per tant s’utilitzen molts pesticides, Espanya i Itàlia, i un en el que es consumeixen menys, Eslovènia. La recerca sobre COPs es centra en dues poblacions de l’Argentina (Salta i Ushuaia) i una de Rússia (Chukotka), Ushuaia i Chukotka es poden considerar remotes. S’ha realitzat una anàlisi química d’un ampli ventall de COPs en mostres de sèrum de dones embarassades, emprant cromatografia de gasos i espectrometria de masses. A més, les concentracions de COPs han estan contrastades amb una sèrie de factors sociodemogràfics. El resultat més destacable es que totes les dones en totes tres poblacions tenen nivells detectables d’algun COP tot i que es van prohibir fa anys. A més, tant la residència de cada una d’elles com l’edat, paritat i l’IMC son uns factors que influencien les concentracions d’OCs. També s’ha trobat una associació positiva entre les concentracions de 4,4’-DDT amb l’edat gestacional, el pes i la longitud dels nadons, suggerint una interacció a nivell metabòlic entre aquest compost i el fetus. L’estudi sobre pesticides organofosforats i piretroides determina la exposició de diferents tipus de poblacions, nens de Trieste (Itàlia), parelles de dones i els seus nens de Ljubljana (Eslòvenia), dones embarassades de Tarragona (Espanya) i població general de zones rurals de Carbia i Sucs a Galícia i Catalunya, respectivament. S’ha desenvolupat una metodologia analítica que permetés les anàlisis dels diferents metabòlits dels pesticides organofosforats i piretroides en l’orina dels grups esmentats. S’ha vist que tant els treballadors agrícoles de Sucs, com les persones que viuen a un entorn rural (Sucs i Carbia) estan més exposats a pesticides organofosforats i piretroides. A més, s’ha trobat una distribució diferent en quant als pesticides organofosforats respecte a altres estudis, el pirimifos té un pes molt important en la població de dones embarassades de Tarragona i nens d’Itàlia. Finalment, s’ha avaluat l’exposició a pesticides organofosforats i piretroides i la seva relació amb la manipulació i utilització d’equips de protecció individual en la població agrícola de Sucs, concloent que l’ús d’EPI es útil i necessari en aquests tipus de treballs., [eng] Over the 50s and 60s different organochlorine and organobromate compounds, classified as persistent organic pollutants, were used all around the world, as pesticides, flame retardants or thermal insulators. In 2001 the Stockholm Convention on POPs recognized their toxicity towards human health and environment and suggested controls with the aim of eliminating and reducing their use. As a consequence new compounds have been synthetized to replace the banned ones, some of them are the organophosphate pesticides (OP) and pyrethroids (PYR). The present research assesses, on one hand, the extent of several persistent organic pollutants (POPs), specifically organochlorine compounds (OCs) and polybrominated diphenyl ethers (PBDEs) in women. And on the other hand, the body burden and exposure of the most important OPs and PYR in general population from three European countries. The study on POPs focuses on two Argentinean populations (Salta and Ushuaia) and one from Russia (Chukotka). A chemical analysis of a wide range of POPs in serum samples from women has been conducted, using gas chromatography and mass spectrometry. Moreover, the POP concentrations were then contrasted with a set of socio-demographic factors. Certain OCs accumulate differently depending on the residence, age, parity and BMI. It has also been found a positive association between 4,4’-DDT with the gestational age, the weight and length of newborns, suggesting a metabolic interaction between this compound and the foetus. The study on OPs and PYR determines the exposure over three different populations, children from Trieste (Italy), mother-child couples from Ljubljana (Slovenia), pregnant women from Tarragona (Spain) and general population from Catalonia and Galicia (Spain). A methodoly has been developed for the quantification of OP and PYR urinary metabolites. A different distribution, according to other studies, has been found, where pirimifos represent an important part of the total OPs in pregnant women from Tarragona and Italian children. Finally, the exposure to these compounds has been assessed according to their manipulation and use among an agricultural population from Catalonia.

Recent studies have proven that vegetables cultivated in peri-urban areas are exposed to a greater concentration of organic microcontaminants (OMCs) and trace elements (TEs) than those grown in rural areas. In this study, the occurrence and human health risk of chemical contaminants (16 TEs and 33 OMCs) in edible parts of lettuce, tomato, cauliflower, and broad beans from two farm fields in the peri-urban area of the city of Barcelona and one rural site outside the peri-urban area were assessed. The concentration of TEs and OMCs (on fresh weight basis) ranged from non-detectable to 17.4 mg/kg and from non-detectable to 256 μg/kg, respectively. Tomato fruits showed the highest concentration of TEs and OMCs. Principal component analysis indicated that the occurrence of chemical contaminants in vegetables depended on the commodity rather than the location (peri-urban vs rural). Risk assessment using hazardous quotient (HQ) and threshold of toxicological concern (TTC) approaches showed that the risk for the consumption of target vegetables in the peri-urban area was low and similar to that observed for the rural site. Total HQ values for TEs were always below 1, and a minimum consumption of 150 g/day for children and 380 g/day for adults is required to reach the TTC due to the presence of pesticides. Further studies are needed to estimate the combined effect of TEs and OMCs on human health. © 2018 The Authors, The authors gratefully acknowledge the financial support of the Spanish Ministry of Economy, Industry and Competitiveness (MEIC) through Project AGL2014-59353-R . A. M. and Dr. V. M. would also like to acknowledge an FPI fellowship ( BES-2015-075745 ) and a Ramon y Cajal contract ( RYC-2013-12522 ) from the MEIC . The authors would further like to greatly thank the officers and farmers of the Baix Llobregat Agrarian Park for their assistance, as well as Ms. Yolanda Rodríguez, Ms. Marta Turull, Ms. Rui You, and Mr. Manel Martín for their technical assistance with the sampling and sample preparation. Appendix A

The suitability of two different tracers to mimic the behavior of pesticides in agricultural soils and to evidence the potential for preferential flow was evaluated in outdoor lysimeter experiments. The herbicide atrazine [6‐chloro‐N‐ethyl‐N′‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine] was used as a model compound. Two tracers were used: a nonadsorbing tracer (bromide) and a weakly adsorbing dye tracer (uranine). Two soils that are expected to show a different extent of macropore preferential flow were used: a well‐drained sandy‐loamy Cambisol (gravel soil) and a poorly drained loamy Cambisol (moraine soil). Conditions for preferential flow were promoted by applying heavy simulated rainfall shortly after pesticide application. In some of the experiments, preferential flow was also artificially simulated by injecting the solutes through a narrow tube below the root zone. With depth injection, preferential leaching of atrazine occurred shortly after application in both soil types, whereas with surface application, it occurred only in the moraine soil. Thereafter, atrazine transport was mainly through the porous soil matrix, although contributions of preferential flow were also observed. For all the application approaches and soil types, after 900 d

Herbicides classified as synthetic auxins have been most commonly used to control broadleaf weeds in a variety of crops and in non-cropland areas since the first synthetic auxin herbicide (SAH), 2,4-D, was introduced to the market in the mid-1940s. The incidence of weed species resistant to SAHs is relatively low considering their long-term global application with 29 broadleaf weed species confirmed resistant to date. An understanding of the context and mechanisms of SAH resistance evolution can inform management practices to sustain the longevity and utility of this important class of herbicides. A symposium was convened during the 2nd Global Herbicide Resistance Challenge (May 2017 in Denver, CO, USA) to provide an overview of the current state of knowledge of SAH resistance mechanisms including case studies of weed species resistant to SAHs and perspectives on mitigating resistance development in SAH-tolerant crops. The authors are arrayed in alphabetical order because each made substantive contributions to the success of the Weed Resistance to Synthetic Auxin Herbicides symposium convened on May 15, 2017 during the Global Herbicide Resistance Challenge meeting in Denver, Colorado,USA. The symposium organizers and speakerswould like to thank the Global Herbicide Resistance Committee (www .hracglobal.com) for their financial support that made the symposium possible. The authors wish to thank Katrina Nelson, Dow AgroSciences, LLC, for her assistance in manuscript preparation. ™ Trademark of The Dow Chemical Company (‘Dow’) or an affiliated company of Dow. ® Trademark of Monsanto Company.