Environmental impacts of an imidaclopridcontaining formulation: from soils to waters

The neonicotinoid pesticide imidacloprid is among the top sold agrochemicals worldwide. Due to its widespread use in mixtures with different solvents and co-adjuvants, studying the environmental impact of its derived commercial formulations has become mandatory. In this study we used laboratory ecotoxicological tests to quantify the impact of the imidacloprid-containing formulation Confidor® 20SL on the terrestrial and aquatic compartments. Lethal and sublethal effects of recommended application doses of the product were assessed on standard terrestrial invertebrates Eisenia fetida and Folsomia candida whereas the toxicity of leachates from contaminated soils was evaluated in the aquatic model organisms Daphnia magna and Raphidocelis subcapitata. The exposure to environmentally relevant concentrations of imidacloprid causedno mortality to earthworms (LC50 of 4.23 mg imidaclopridkg-1 dry soil) but altered their behavior and reproductionpatterns (EC50 values for avoidance and reproduction testsof 0.43 and 1.40 mg imidacloprid kg-1 dry soil, respectively).Effects on collembolans F. candida were negligible.Imidacloprid presented moderate leachability, with recoveryrates that ranged from 25.4 to 50.4% of the amountpresent in soils and concentrations in water extracts from13.05 to 71.8 μg L-1. Standard aquatic ecotoxicity testswere not able detect chronic or acute toxicity in standardtest organisms. Nonetheless, concentrations of the insecticidein water extracts were high enough to pose a lethalthreat to several other non-standard aquatic organisms

Modeling of High Nanoparticle Exposure in an Indoor Industrial Scenario with a One-Box Model

Mass balance models have proved to be effective tools for exposure prediction in occupational settings. However, they are still not extensively tested in real-world scenarios, or for particle number concentrations. An industrial scenario characterized by high emissions of unintentionally-generated nanoparticles (NP) was selected to assess the performance of a one-box model. Worker exposure to NPs due to thermal spraying was monitored, and two methods were used to calculate emission rates: the convolution theorem, and the cyclic steady state equation. Monitored concentrations ranged between 4.2 × 104–2.5 × 105 cm−3. Estimated emission rates were comparable with both methods: 1.4 × 1011–1.2 × 1013 min−1 (convolution) and 1.3 × 1012–1.4 × 1013 min−1 (cyclic steady state). Modeled concentrations were 1.4-6 × 104 cm−3 (convolution) and 1.7–7.1 × 104 cm−3 (cyclic steady state). Results indicated a clear underestimation of measured particle concentrations, with ratios modeled/measured between 0.2–0.7. While both model parametrizations provided similar results on average, using convolution emission rates improved performance on a case-by-case basis. Thus, using cyclic steady state emission rates would be advisable for preliminary risk assessment, while for more precise results, the convolution theorem would be a better option. Results show that one-box models may be useful tools for preliminary risk assessment in occupational settings when room air is well mixed

Testing the performance of one and two box models as tools for risk assessment of particle exposure during packing of inorganic fertilizer

Modelling of particle exposure is a useful tool for preliminary exposure assessment in workplaces. However, actual exposure measurements are needed to assess models reliability. Worker exposure was monitored during packing of a complex inorganic granulate fertilizer at industrial scale using small and big bags. Particle concentrations were modelled with one and two box models, where the emission source was estimated with the fertilizer’s dustiness index. The exposure levels were used to calculate inhaled dose rates and test accuracy of the exposure modellings. The particle number concentrations were measured from worker area by using a mobility and optical particle sizer which were used to calculate surface area and mass30 concentrations. The concentrations in the worker area during pre-activity ranged from 63797 - 81073 cm-3, 4.6x106 to 7.5x106 um2 cm-3, and 354 to 634 μg m-3 31 (respirable mass fraction) and during packing from 50300 to 85949 cm-3, 4.3x106 to 7.6x106 um2 32 cm-3, and 279 to 668 μg m-3 33 (respirable mass fraction). Thus, the packing process did not significantly increase the exposure levels. High particle number concentration was partly due to the use of diesel-powered forklifts. The particle surface area deposition rate in respiratory tract was up to 7.6x106 μm2 min-1 during packing, with 52% - 61% of deposition occurring in the alveolar region. Ratios of the modelled and measured concentrations were 0.98 ± 0.19 and 0.84 ± 0.12 for small and big bags, respectively, when using the one box model, and 0.88 ± 0.25 and 0.82 ± 0.12, for small and big bags, respectively, when using the one box model, and 0.88 ± 0.25 and 0.82 ± 0.12, respectively, when using the two box model. The modelling precision improved for both models when outdoor particle concentrations were included. This study shows that exposure concentrations during packing of fertilizers can be predicted with a reasonable accuracy by using a concept of dustiness and mass balance models

Estudi de l'impacte ecotoxicològic de l'insecticida imidacloprid en diferents compartiments ambientals

En les darreres dècades la necessitat d'una major producció en l'agricultura ha implicat l'ús de productes químics per a millorar la producció. Entre aquests productes trobem els insecticides que, tot i ser específics per a determinades funcions, en molts casos acaben afectant també a altres organismes que no en són la diana. Els assajos d'ecotoxicitat són una eina clau per a determinar el grau d'afectació d'aquests insecticides. En aquest estudi es pretén determinar l'efecte de l'aplicació directa en el sòl de les dosis recomanades de l'insecticida Confidor 20SL (amb imidacloprid com a principi actiu) sobre Eisenia fetida i dels lixiviats d'aquests sòls sobre Daphnia magna i Selenastrum capricornutum simulant fenòmens d'escorrentia o lixiviació naturals. En el cas de E.fetida s'obté una LC50 de 24.71 mg/kg sòl i per la reproducció un valor de EC50 de 8.41 mg/kg sòl. S'observa allunyament en totes les dosis utilitzades i la EC50 és de 2.57 mg/kg sòl. No s'han pogut determinar efectes a nivell neurològic a partir de la determinació de l'activitat de l' AChE. A l'exposar D.magna als lixiviats del sòl contaminat no s'han observat efectes clars ni en la mortalitat ni en la reproducció. El mateix succeeix amb S.capricornutum. Les dosis d'aplicació del pesticida Confidor, representen una amenaça per a E.fetida pel que fa a efectes subletals però no podem dir el mateix per als organismes aquàtics.Durante las últimas décadas la necesidad de una mayor producción en la agricultura ha implicado el uso de productos químicos para mejorar la producción. Entre estos productos encontramos los insecticidas que, aun siendo específicos para determinadas acciones, en muchas ocasiones afectan también a organismos no diana. Los ensayos de ecotoxicidad constituyen una herramienta esencial para determinar el grado de afectación de estos insecticidas. En este estudio se pretende determinar el efecto de la aplicación directa en el suelo de las dosis recomendadas del insecticida Confidor 20SLDuring the last decades, the need of increasing agricultural production in has triggered the use of many chemicals to improve production. Among these products we find insecticides that, despite their specificity for certain functions, can effect non- target organisms. Ecotoxicity tests have become a key tool to determine how these insecticides affect the enviroment. This study aims to determine the effects that the direct application of field doses of the insecticide Confirdor (a.i imidacloprid) on soil cause to Eisenia fetida, and the effects that leachates from these soils have on Daphnia magna and Selenastrum capricorutum, simulating natural effects of run-off and leaching. In the case of 1.reproduction was 8.41 mg/kg soil. Avoidance response was observed in all concentrations and the EC50 was 2.57 mg/kg soil. Effects at neurological level by determination of acetylcholine esterase activity determinations could not been determined. Exposure of D.magna to leachates from contaminated soils showed no effects in mortality or in reproduction. The same occurred with S.capricornutum. The application of the pesticide Confidor in its file doses, represent a threat for E.fetida at sublethal levels but the same cannot be said for aquatic organisms

Health risk assessment from exposure to particles during packing in working environments

Packing of raw materials in work environments is a known source of potential health impacts (respiratory, cardiovascular) due to exposure to airborne particles. This activity was selected to test different exposure and risk assessment tools, aiming to understand the effectiveness of source enclosure as a strategy to mitigate particle release. Worker exposure to particle mass and number concentrations was monitored during packing of 7 ceramic materials in 3 packing lines in different settings, with low (L), medium (M) and high (H) degrees of source enclosure. Results showed that packing lines L and M significantly increased exposure concentrations (119-609 μg m-3 respirable, 1150-4705 μg m-3 inhalable, 24755-51645 cm-3 particle number), while nonsignificant increases were detected in line H. These results evidence the effectiveness of source enclosure as a mitigation strategy, in the case of packing of ceramic materials. Total deposited particle surface area during packing ranged between 5.4-11.8x105 μm2 min-1, with particles depositing mainly in the alveoli (51-64%) followed by head airways (27-41%) and trachea bronchi (7-10%). The comparison between the results from different risk assessment tools (Stoffenmanager, ART, NanoSafer) and the actual measured exposure concentrations evidenced that all of the tools overestimated exposure concentrations, by factors of 1.5-8. Further research is necessary to bridge the current gap between measured and modelled health risk assessments

Environmental impacts of an imidacloprid-containing formulation: from soils to waters

El pesticida neonicotinoide imidacloprid se encuentra entre los agroquímicos más vendidos en todo el mundo. Debido a su amplio uso en mezclas con diferentes disolventes y co-adyuvantes, estudiar el impacto ambiental de las formulaciones comerciales derivadas se ha convertido en obligatorio. En este estudio se utilizaron ensayos ecotoxicológicos de laboratorio para cuantificar el impacto del ConfidorR 20SL (formulación que contiene imidacloprid) en los compartimentos terrestre y acuático. Los efectos letales y subletales de las dosis recomendadas de aplicación del producto fueron evaluadas en los invertebrados terrestres Eisenia foetida y Folsomia candida mientras que la toxicidad de los lixiviados de los suelos contaminados se evaluó en los organismos acuáticos modelo Daphnia magna y Raphidocelis subcapitata (anteriormente Selenastrum capricornutum). La exposición a concentraciones ambientalmente relevantes de imidacloprid no causo mortalidad en las lombrices de tierra (CL50 de 4.23 mg de imidacloprid por kg de suelo seco) pero altero los patrones de comportamiento y reproducción (valores de CE50 de 0.43 y 1.40 mg de imidacloprid por kg de suelo seco en los ensayos de alejamiento y reproducción respectivamente). Los efectos en los colembolos F. candida fueron despreciables. El imidacloprid presento una lixiviabilidad moderada, con tasas de recuperación en los extractos acuosos que fueron del 25.4 al 50.4% de la cantidad presente en los suelos y concentraciones de 13.05 a 71.8 µg por litro. Las pruebas estándar de ecotoxicidad acuática no fueron capaces de detectar toxicidad aguda o crónica en los organismos de ensayo. Sin embargo, las concentraciones de insecticida en los extractos fueron lo suficientemente grandes como para representar una amenaza letal para otros organismos acuáticos no estándarThe neonicotinoid pesticide imidacloprid is among the top sold agrochemicals worldwide. Due to its widespread use in mixtures with different solvents and co-adjuvants, studying the environmental impact of its derived commercial formulations has become mandatory. In this study we used laboratory ecotoxicological tests to quantify the impact of the imidacloprid-containing formulation Confidor R20SL on the terrestrial and aquatic compartments. Lethal and sublethal effects of recommended application doses of the product were assessed on standard terrestrial invertebrates Eisenia fetida and Folsomia candida whereas the toxicity of leachates from contaminated soils was evaluated in the aquatic model organisms Daphnia magna and Raphidocelis subcapitata. The exposure to environmentally relevant concentrations of imidacloprid caused no mortality to earthworms (LC50 of 4.23 mg imidacloprid kg-1 dry soil) but altered their behavior and reproduction patterns (EC50 values for avoidance and reproduction tests of 0.43 and 1.40 mg imidacloprid kg-1 dry soil, respectively). Effects on collembolans F. candida were negligible. Imidacloprid presented moderate leachability, with recovery rates that ranged from 25.4 to 50.4% of the amount present in soils and concentrations in water extracts from 13.05 to 71.8 µg L-1. Standard aquatic ecotoxicity tests were not able detect chronic or acute toxicity in standard test organisms. Nonetheless, concentrations of the insecticide in water extracts were high enough to pose a lethal threat to several other non-standard aquatic organismsPostprint (published version

Worker exposure to airborne particles in industrial settings: evaluation of exposure assessment and modelling tool

[eng] Exposure to particulate matter in work environments has been linked to ischemic heart, cardiovascular and respiratory-related disease risk increase due to inhalation. Increased adverse health effects have been linked to nanoparticles (< 100 nm) due to their ability to reach the deepest sections of the respiratory tract and their longer retention time. Exposure monitoring is widely used method to assess worker exposure to airborne particles. However, other prediction tools have been explored such as the use of the dustiness index, mass-balance models, and health risk assessment tools. Discussions regarding the use and application of the latter tools are ongoing due to their relatively novelty for worker exposure assessment, the need to test their performance under real- world scenarios, and the need to understand the uncertainties related to critical parameters and limitations. The main objectives of this PhD Thesis are to 1) assess worker exposure to particles (4 nm - 35 μm) in ceramic industry real-world workplace scenarios; 2) evaluate currently used exposure assessment metrics and decision-making approaches; 3) understand the relationship between material dustiness and worker exposure; 4) evaluate the performance of mass-balance models, and 5) compare health risk assessment tools. Worker exposure was assessed during mechanical handling of powders in 6 different scenarios and for 15 materials as well as thermal spraying of ceramic coatings. Exposure monitoring was conducted using online and offline instruments which allowed for the characterization of particle mass and number concentrations, particle size and size distribution, particle morphology and chemical composition. In addition, some of these scenarios were also selected to assess relationship between the dustiness index and exposure concentrations as well as the ability of different particle metrics to represent worker exposure. Finally, decision making approaches, and the performance of mass- balance models and risk assessment tools were tested. Results evidenced clear impacts of industrial activities on workplace exposure to coarse, fine and nanoparticles. Significant increases of inhalable and respirable particle mass concentrations (inhalable mass concentration 80-4000 μg m-3) were observed during mechanical handling of raw materials (d50 2.7-40 µm), when compared to background concentrations. The highest mean inhalable mass concentration (3700 μg m-3) was monitored during packing of ceramic materials, when mitigation strategies were inefficiently implemented. Conversely, particle number concentrations were not influenced by mechanical handling of powders, but by driving of diesel-powdered forklifts, leading to concentrations up to 70000 cm-3. Thermal spraying, on the other hand, increased particle number concentration up to 105 cm-3 in the worker area. After the application of the ICRP respiratory tract deposition model, airborne particles in the workplaces studied were seen to deposit mainly in the alveolar region (51-64%) during packing of powder materials and (54-70%) during thermal spraying by means of surface area. Source enclosure and modification of the energy settings were pointed out as useful strategies to minimize worker exposure. The validity, performance and comparability of tools for exposure assessment were evaluated. Several decision-making approaches were tested to determine statistically significant impacts on exposure. Among them, the ARIMA models were seen to be the least conservative while the nanoGEM approach confirmed its usefulness for particle number but slightly underestimated exposure for particle mass concentrations when compared to traditional statistical tests. High degree of correlation was found between dustiness and measured exposure concentrations during mechanical handling of powders in a pilot plant (R2 up to 0.97) and at industrial scale (R2 up to 0.80). This correlation was stronger when material characteristics dominated over process characteristics, and an adequate methodology is applied, using the dustiness method which best mimics the activity under study. Finally, one- and two-box models were used to model particles under high and low concentrations in terms of mass and particle number concentrations. Ratios between modelled and measured concentrations were 0.82-1.22 when modelling inhalable particle mass in the mechanical handling scenario, whereas ratios of 0.2-0.7 were obtained when modelling thermal spraying particles. Thus, model performance was poorer for the high nanoparticle concentration scenario. The addition of background and outdoor concentrations as input improved model performance. Risk assessment and control banding tools (ART, Stoffenmanager and NanoSafer) were tested for the scenarios under study, and it was concluded that the mechanical processes were estimated with higher accuracy and lower variability by Stoffenmanager (64% of the cases). Conversely, ART and NanoSafer showed higher flexibility for introducing more case-specific input data. A clear need for harmonization between risk assessment tools was evidenced.[cat] dels materials en planta pilot (R2 fins a 0.97) i en escala industrial (R2 fins a 0.80). Aquesta correlació s’ha vist reforçada quan les característiques dels materials dominen sobre les característiques del procés, i quan una metodologia adequada per a la determinació del poder d’emissió de pols va ser utilitzada, aquella que millor simula el procés d’estudi. Finalment, es van utilitzar els models basats en balanços de massa de una i dos caixes per a modelar dos escenaris diferents, un de baixa exposició a partícules grolleres (manipulació mecànica, ensacat de materials) y un altre d’altes concentracions de numero de partícules (projecció tèrmica). Les proporcions entre les concentracions modelades/mesurades van ser de 0.82-1.22 per a la modelització de la fracció màssica de pols inahalble en el cas de la manipulació mecànica, mentre que les proporcions van ser de 0.2-0.7 per a la modelització de la concentració en numero de partícules durant la projecció tèrmica. Per tant, la bondat dels models basats en balanços de massa va ser menor en l’escenari d’altes concentracions de numero de partícules. Al considerar les concentracions de fons i de l’aire ambient en els models, la bondat i la precisió dels models va augmentar. De les tres eines per a l’avaluació de riscos per exposició a agents químics (ART, Stoffenmanager i NanoSafer) que van ser provades, les concentracions mesurades durant els processos de manipulació mecànica van ser estimats amb una major precisió i menor variabilitat per Stoffenmanager (64% dels cases). Per el contrari, ART i NanoSafer van mostrar tenir una major flexibilitat per a introduir dades d’entrada especifiques per a cada cas

Activitats dels enzims implicats en el metabolisme de contaminants en peixos del Mediterrani en un gradient de profunditat

Trabajo final presentado por Carla Ribalta para un Máster de la Universitat de Barcelona (UB), realizado bajo la dirección de la Dra. Montserrat Solé del Institut de Ciències del Mar (ICM-CSIC).-- 41 pages, 4 figures, 5 tablesS’han determinat les activitats involucrades en el metabolisme detoxificador de diferents espècies del Mediterrani que habiten a diferents profunditats. El focus principal és en aquelles espècies que habiten les zones més profundes, per a les quals la informació és més limitada. Per tal de comparar les activitats segons la fondària s’han seleccionat dues espècies costaneres, Solea solea i Dicentrarchus labrax, dues de mitjana profunditat, Trachyrincus scabrus i Mora moro i dues de gran fondària Alepocephalus rostratus i Cataetyx laticeps. Les activitats hepàtiques mesurades han estat aquelles involucrades amb el citocrom P450 (CYP) (EROD: 7-etoxiresorufin-O-deetilasa, BFCOD: 7-benziloxi-4-trifluorometilcumarin-O-debenziloxlasa, ECOD: 7-etoxicumarin-O-deetilasa i MROD: 7-metoxiresorufin-O-deetilasa) i les Carboxilesterases (CbEs). També s’han mesurat activitats de conjugació (UDPGA: UDP-glucuronosiltransferasa i GST: glutatió-S-transferasa) i antioxidants (CAT: catalasa, GPX: glutatió peroxidasa i GR: glutatió reductasa). Per altra banda, usant una tècnica in vitro, s’han estudiat les interaccions de diferents xenobiòtics amb les activitats del CYP450. Els contaminants seleccionat han estat els fàrmacs diclofenac, fluoxetina, i gemfibrozil i els productes d’higiene personal galaxolide, nonilfenol i triclosan. Tots ells considerats contaminants emergents amb un potencial risc per als organismes del medi aquàtic. Tot i que les concentracions superiors d’aquests contaminants han estat trobats en aigües continentals, són diversos els estudis que apunten l’acumulació de diferents compostos, entre els quals hi ha algun dels xenobiòtics esmentats, en els teixits de peixos que habiten a grans profunditats causant diversos efectes biològics. Pel que fa a les activitats basals,s’han observat grans diferències entre espècies i per a algunes s’ha trobat relació amb les profunditats que habiten, però per altres sembla que pugin ser altres factors els que tenen una major influència. En quant a les interaccions dels compostos cal destacar la sensibilitat observada per T. sacbru

Estudi de l'impacte ecotoxicològic de l'insecticida imidacloprid en diferents compartiments ambientals

En les darreres dècades la necessitat d’una major producció en l’agricultura ha implicat l’ús de productes químics per a millorar la producció. Entre aquests productes trobem els insecticides que, tot i ser específics per a determinades funcions, en molts casos acaben afectant també a altres organismes que no en són la diana. Els assajos d’ecotoxicitat són una eina clau per a determinar el grau d’afectació d’aquests insecticides. En aquest estudi es pretén determinar l’efecte de l’aplicació directa en el sòl de les dosis recomanades de l’insecticida Confidor 20SL (amb imidacloprid com a principi actiu) sobre Eisenia fetida i dels lixiviats d’aquests sòls sobre Daphnia magna i Selenastrum capricornutum simulant fenòmens d’escorrentia o lixiviació naturals. En el cas de E.fetida s’obté una LC50 de 24.71 mg/kg sòl i per la reproducció un valor de EC50 de 8.41 mg/kg sòl. S’observa allunyament en totes les dosis utilitzades i la EC50 és de 2.57 mg/kg sòl. No s’han pogut determinar efectes a nivell neurològic a partir de la determinació de l’activitat de l’ AChE. A l’exposar D.magna als lixiviats del sòl contaminat no s’han observat efectes clars ni en la mortalitat ni en la reproducció. El mateix succeeix amb S.capricornutum. Les dosis d’aplicació del pesticida Confidor, representen una amenaça per a E.fetida pel que fa a efectes subletals però no podem dir el mateix per als organismes aquàtics.Durante las últimas décadas la necesidad de una mayor producción en la agricultura ha implicado el uso de productos químicos para mejorar la producción. Entre estos productos encontramos los insecticidas que, aun siendo específicos para determinadas acciones, en muchas ocasiones afectan también a organismos no diana. Los ensayos de ecotoxicidad constituyen una herramienta esencial para determinar el grado de afectación de estos insecticidas. En este estudio se pretende determinar el efecto de la aplicación directa en el suelo de las dosis recomendadas del insecticida Confidor 20SL (con imidacloprid como principio activo) sobre Eisenia fetida i de los lixiviados de este suelo sobre Dafnia magna i Selenastrum capricornutum simulando efectos de escorrentía i lixiviación naturales. En el caso de E.fetida se obtiene una LC50 de 24.71 mg/kg suelo y para la reproducción un valor de EC50 de 8.41 mg/kg suelo. Se observa alejamiento en todas les dosis utilizadas con una EC50 de 2.57 mg/kg suelo. No se han podido determinar efectos a nivel neurológico a partir de la determinación de la actividad de la AChE. Al exponer D.magna a los lixiviados del suelo contaminado no se han observado efectos claros ni en la mortalidad ni en la reproducción. Lo mismo sucede con S.capricornutum. Las dosis de aplicación del pesticida Confidor, representan una amenaza para E.fetida a nivel de efectos subletales pero no podemos decir lo mismo para los organismos acuáticos.During the last decades, the need of increasing agricultural production in has triggered the use of many chemicals to improve production. Among these products we find insecticides that, despite their specificity for certain functions, can effect non- target organisms. Ecotoxicity tests have become a key tool to determine how these insecticides affect the enviroment. This study aims to determine the effects that the direct application of field doses of the insecticide Confirdor (a.i imidacloprid) on soil cause to Eisenia fetida, and the effects that leachates from these soils have on Daphnia magna and Selenastrum capricorutum, simulating natural effects of run-off and leaching. In the case of 1.reproduction was 8.41 mg/kg soil. Avoidance response was observed in all concentrations and the EC50 was 2.57 mg/kg soil. Effects at neurological level by determination of acetylcholine esterase activity determinations could not been determined. Exposure of D.magna to leachates from contaminated soils showed no effects in mortality or in reproduction. The same occurred with S.capricornutum. The application of the pesticide Confidor in its file doses, represent a threat for E.fetida at sublethal levels but the same cannot be said for aquatic organisms

In Vitro Interaction of Emerging Contaminants with the Cytochrome P450 System of Mediterranean Deep-Sea Fish

9 pages, 3 figures, 3 tables© 2014 American Chemical Society. The interactions of emerging contaminants with the xenobiotic and endogenous metabolizing system of deep-sea fish were compared. The drugs diclofenac, fluoxetine, and gemfibrozil belong to different pharmaceutical classes with diverse mechanistic actions, and the personal care products triclosan, galaxolide, and nonylphenol are representative of antibacterial agents, nitro-musks, and surfactants, respectively. The fish compared are representative of the middle and lower slope of deep-sea habitats. The species were adults of Trachyrynchus scabrus, Mora moro, Cataetix laticeps, and Alepocehalus rostratus. The hepatic metabolic system studied were the activities associated with several cytochrome P450 isoforms (CYPs): 7-ethoxyresorufin-O-deethylase (EROD), benzyloxy-4-[trifluoromethyl]-coumarin-O-debenzyloxylase (BFCOD), and 7-ethoxycoumarin-O-deethylase (ECOD). Results showed differences in baseline activities and sensitivity to chemicals which were species, chemical, and pathway dependent. T. scabrous was the most sensitive species to chemical interactions with the xenobiotic and endogenous metabolizing (EROD and BFCOD) systems, especially in the case of diclofenac interference with BFCOD activity (IC50 = 15.7 ± 2.2 μM). Moreover, T. scabrous and A. rostratus possessed high basal ECOD activity, and this was greatly affected by in vitro exposure to diclofenac in T. scabrous also (IC50 = 6.86 ± 1.4 μM). These results highlight the sensitivity of marine fish to emerging contaminants and propose T. scabrous (middle slope) and A. rostratus (lower slope) as sentinels and the inclusion of ECOD activity as a sensitive biomarker to these exposuresThis work was financed by Spain’s Ministry of Science and Innovation (ref CTM2007-66316-C02-02/MAR-PROMETEO and CTM2010-16611-DEPURAMAR)Peer Reviewe