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First measurement of human exposure to current use pesticides (CUPs) in the atmosphere of central Chile: The case study of Mauco cohort Full text
2020
Cortés, Sandra | Pozo, Karla | Llanos, Yasna | Martínez, Natalia | Foerster, Claudia | Leiva, Cinthya | Ustáriz, Javier | Přibylová, Petra | Klánová, Jana | Jorquera, Héctor
Chile is a leading agricultural producer and thus consumer of insecticides, herbicides, and fungicides. In Molina, Central Chile, a prospective cohort has been established for studying the incidence and risk factors of chronic diseases in the adult population. Our goals were to measure airborne current use pesticides (CUPs), assess their spatial distribution and potential sources, and estimate health risks for the population in Molina. CUPs were measured using passive air samplers (PAS), deployed on six sites from October 2015 to August 2016. Thirty-eight pesticides were analyzed using high performance liquid chromatography (HPLC), but only nine of them were detected. Chlorpyrifos (CPF) was detected with air concentrations ranging from 444 to 14 624 (pg m(-3)). Diazinon, atrazine, dimethoate, metolachlor, simazine, terbuthylazine and tebuconazole were also detected; only pendimethalin had concentrations as high as those of CPF, with a maximum of 14 927 (pg m(-3)). Backward wind trajectories were used to estimate locations of potential sources contributing to airborne CUPs concentrations. Most of the exposure to CUPs was associated with local sources, while regional sources southern/eastern/western of Molina appear to contribute as secondary sources (soil evaporation followed by atmospheric transport) in spring and summer seasons. A health risk assessment using US-EPA's methodology was carried out for inhalation exposure of detected pesticides. None of the measured CUPs were associated with a hazard quotient (HQ) greater than 1, indicating no significant risk due to inhalation of pesticides in Molina's population with the exception of the group of children below 12 years old. However, further investigations are needed to evaluate others CUPs exposure route such as food consumption and dermal exposure to improve our health risk estimations. | Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) 15130011-15110020 180078 1161673 Vicerrectoria de Investigacion, Pontificia Universidad Catolica de Chile 9/2014 RECETOX Research Infrastructure LM2015051 CZ.02.1.01/0.0/0.0/16_013/0001761
Show more [+] Less [-]Ecotoxicoproteomic assessment of the functional alterations caused by chronic metallic exposures in gammarids Full text
2017
Gismondi, Eric | Thomé, Jean-Pierre | Urien, Nastassia | Uher, Emmanuelle | Baiwir, Dominique | Mazzucchelli, Gabriel | De Pauw, Edwin | Fechner, Lise | Lebrun, Jérémie | FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
peer reviewed | Very few ecotoxicological studies have been performed on long-term exposure under controlled conditions, hence limiting the assessment of the impact of chronic and diffuse chemical pressures on the health of aquatic organisms. In this study, an ecotoxicoproteomic approach was used to assess the integrated response and possible acclimation mechanisms in Gammarus fossarum following chronic exposures to Cd, Cu or Pb, at environmentally realistic concentrations (i.e. 0.25, 1.5 and 5 µg/L respectively). After 10-week exposure, changes in protein expression were investigated in caeca of control and exposed males. Gel-free proteomic analyses allowed for the identification of 35 proteins involved in various biological functions, for which 23 were significantly deregulated by metal exposures. The protein deregulation profiles were specific to each metal, providing evidence for metal-specific action sites and responses of gammarids. Among the tested metals, Cu was the most toxic in terms of mortality, probably linked with persistent oxidative stress. Moulting and osmoregulation were the major biological functions affected by Cu in the long-term. In Pb-exposed gammarids, significant deregulations of proteins involved in immune response and cytoskeleton were observed. Reproduction appears to be strongly affected in gammarids chronically exposed to Cd or Pb. Besides, modified expressions of several proteins involved in energy transfer and metabolism highlighted important energetic reshuffling to cope with chronic metal exposures. These results support the fact that metallic pressures induce a functional and energetic cost for individuals of G. fossarum with potential repercussions on population dynamics. Furthermore, this ecotoxicoproteomic study offers promising lines of enquiry in the development of new biomarkers that could make evidence of long-term impacts of metals on the health of organisms.
Show more [+] Less [-]Microplastics in the insular marine environment of the Southwest Indian Ocean carry a microbiome including antimicrobial resistant (AMR) bacteria: A case study from Reunion Island Full text
2024
Sababadichetty, Loik | Miltgen, Guillaume | Vincent, Bryan | Guilhaumon, François | Lenoble, Véronique | Thibault, Margot | Bureau, Sophie | Tortosa, Pablo | Bouvier, Thierry | Jourand, Philippe
The increasing threats to ecosystems and humans from marine plastic pollution require a comprehensive assessment. We present a plastisphere case study from Reunion Island, a remote oceanic island located in the Southwest Indian Ocean, polluted by plastics. We characterized the plastic pollution on the island's coastal waters, described the associated microbiome, explored viable bacterial flora and the presence of antimicrobial resistant (AMR) bacteria. Reunion Island faces plastic pollution with up to 10,000 items/km2 in coastal water. These plastics host microbiomes dominated by Proteobacteria (80 %), including dominant genera such as Psychrobacter, Photobacterium, Pseudoalteromonas and Vibrio. Culturable microbiomes reach 107 CFU/g of microplastics, with dominance of Exiguobacterium and Pseudomonas. Plastics also carry AMR bacteria including β-lactam resistance. Thus, Southwest Indian Ocean islands are facing serious plastic pollution. This pollution requires vigilant monitoring as it harbors a plastisphere including AMR, that threatens pristine ecosystems and potentially human health through the marine food chain.
Show more [+] Less [-]Measurements of underwater noise radiated by commercial ships at a cabled ocean observatory Full text
2020
Zhang, Guosong | Forland, Tonje Nesse | Johnsen, Espen | Pedersen, Geir | Dong, Hefeng
Measurements of underwater noise radiated under ship normal operations are presented. The acoustic data, from the cabled ocean observatory, are analyzed under each identified ship passage, which was obtained by the Automatic Identification System. Under each passage, sound pressure level is calculated to observe local noise variations due to shipping noise. This paper emphasizes the study of noise variations at the observatory, presents the noise measurements under identified ship passages in the last several years, and provides references for predictive models of underwater noise pollution from commercial ship traffic. From the passages of one ship to the passages of 26 ships, the measurements reveal similar variation patterns when the ships traveled at similar courses, but different patterns when they traveled at different courses. When evaluating the noise variations due to ship traffics, it is important to consider the shipping noise propagation as well as ship movement. | publishedVersion
Show more [+] Less [-]The 2016 red tide crisis in southern Chile: Possible influence of the mass oceanic dumping of dead salmons Full text
2020
Armijo, Julien | Oerder, Vera | Auger, Pierre-Amaël | Bravo Lizana, Angela | Molina, Ernesto
In 2016, a massive harmful algal bloom (HAB) of Alexandrium catenella around Chiloe island caused one of the major socio-ecological crisis in Chilean history. This red tide occurred in two distinct pulses, the second, most anomalous, bursting with extreme toxicity on the Pacific coast, weeks after the highly controversial dumping off Chiloe of 4,700 t of rotting salmons, killed by a previous HAB of Pseudochattonella verruculosa. We study the transport of this pollution, analyzing the physical oceanographic conditions during and after the dumping. We find that a cyclonic gyre was present between the dumping site and the coast, visible in satellite altimetry and sea surface temperature data. Using Lagrangian simulations, we confirm that near-surface currents could have brought part of the pollution to the coast, and fueled the bloom. This scenario explains also the anomalous later finding of ammonium near Chiloe. Finally we discuss the mismanagement of risk throughout the events. | Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) CONICYT FONDECYT 3150587
Show more [+] Less [-]Development of a flux DMT with integrated adsorptive stripping voltammetry for free metal ions detection in solution Full text
2018
Janot, Noemie | Rotureau, Elise | Pinheiro, Jose Paulo
Development of a flux DMT with integrated adsorptive stripping voltammetry for free metal ions detection in solution. Interfaces Against Pollution
Show more [+] Less [-]Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling Full text
2018
Janot, Noemie | Huot, Hermine | Otero-Fariña, Alba | Leguédois, Sophie | Groenenberg, Jan E.
Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling. Interfaces Against Pollution
Show more [+] Less [-]Transboundary river water quality assessment: a case study of Kabul River Basin, Pakistan Full text
2025
Hussain, Kashif | Iqbal, Muhammad Shahid | Munir, Sarfraz | Bilal, H.
In developing countries, microbial contamination of freshwater resources is a significant public health concern. The concentrations of Escherichia coli (E. coli) and influencing factors in the Kabul River Basin (KRB), Pakistan, were evaluated in this research, using the Soil and Water Assessment Tool (SWAT) model under various climate change scenarios. Streamflow (R2 = 0.66–0.71, NSE = 0.62–0.68) and E. coli (R2 = 0.70, NSE = 0.69) concentrations were utilized to calibrate and validate the model. Higher values of E. coli concentrations (3.55 to 5.20 log cfu/100 ml) were observed during flood events. In 2050, according to Scenario-P1, point sources (human settlements) accounted for 19.7% of E. coli concentrations, non-point sources (livestock) for 46.8%, and upstream sources for 33.5%. This data is based on a moderate growth scenario that incorporates enhanced sanitation. In Scenario-P1, the quantity of E. coli decreased by 70% in comparison to the initial value. Additional advancements in sanitation practices and manure treatment (scenarios Aa, Ab, Ac) resulted in significant decreases in E. coli concentrations, reaching as low as 96%. On the contrary, under standard operating conditions (Scenario-P2), where sanitation and effluent treatment were inadequate, the prevalence of E. coli escalated by 158% by 2050 and further escalated by 201% by 2100. E. coli concentrations were influenced by climate change in conjunction with socioeconomic factors. To reduce E. coli concentrations in the KRB, enhanced sanitation, wastewater treatment, and manure management are emphasized in this study. The findings underscore the urgent need for immediate, robust interventions in wastewater treatment and sanitation infrastructure to prevent further public health risks. Without these critical improvements, the future health of the Kabul River Basin’s population will remain under significant threat from escalating waterborne diseases, exacerbated by climate change.
Show more [+] Less [-]Compost addition reduces porosity and chlordecone transfer in soil microstructure Full text
2016
Woignier T. | Clostre F. | Fernandes P. | Rangon L. | Soler A. | Lesueur Jannoyer M.
Compost addition reduces porosity and chlordecone transfer in soil microstructure Full text
2016
Woignier T. | Clostre F. | Fernandes P. | Rangon L. | Soler A. | Lesueur Jannoyer M.
Chlordecone, an organochlorine insecticide, pollutes soils and contaminates crops and water resources and is biomagnified by food chains. As chlordecone is partly trapped in the soil, one possible alternative to decontamination may be to increase its containment in the soil, thereby reducing its diffusion into the environment. Containing the pesticide in the soil could be achieved by adding compost because the pollutant has an affinity for organic matter. We hypothesized that adding compost would also change soil porosity, as well as transport and containment of the pesticide. We measured the pore features and studied the nanoscale structure to assess the effect of adding compost on soil microstructure. We simulated changes in the transport properties (hydraulic conductivity and diffusion) associated with changes in porosity. During compost incubation, the clay microstructure collapsed due to capillary stresses. Simulated data showed that the hydraulic conductivity and diffusion coefficient were reduced by 95 and 70 % in the clay microstructure, respectively. Reduced transport properties affected pesticide mobility and thus helped reduce its transfer from the soil to water and to the crop. We propose that the containment effect is due not only to the high affinity of chlordecone for soil organic matter but also to a trapping mechanism in the soil porosity. (Résumé d'auteur)
Show more [+] Less [-]Compost addition reduces porosity and chlordecone transfer in soil microstructure Full text
2016
Woignier, Thierry | Clostre, Florence | Fernandes, Paula | Rangon, Luc | Soler, Alain | Lesueur Jannoyer, Magalie
Chlordecone, an organochlorine insecticide, pollutes soils and contaminates crops and water resources and is biomagnified by food chains. As chlordecone is partly trapped in the soil, one possible alternative to decontamination may be to increase its containment in the soil, thereby reducing its diffusion into the environment. Containing the pesticide in the soil could be achieved by adding compost because the pollutant has an affinity for organic matter. We hypothesized that adding compost would also change soil porosity, as well as transport and containment of the pesticide. We measured the pore features and studied the nanoscale structure to assess the effect of adding compost on soil microstructure. We simulated changes in the transport properties (hydraulic conductivity and diffusion) associated with changes in porosity. During compost incubation, the clay microstructure collapsed due to capillary stresses. Simulated data showed that the hydraulic conductivity and diffusion coefficient were reduced by 95 and 70 % in the clay microstructure, respectively. Reduced transport properties affected pesticide mobility and thus helped reduce its transfer from the soil to water and to the crop. We propose that the containment effect is due not only to the high affinity of chlordecone for soil organic matter but also to a trapping mechanism in the soil porosity.
Show more [+] Less [-]Fluoride in weathered rock aquifers of southern India: managed aquifer recharge for mitigation Full text
2016
Brindha, Karthikeyan | Jagadeshan, G. | Kalpana, L. | Elango, L.
Fluoride in weathered rock aquifers of southern India: managed aquifer recharge for mitigation Full text
2016
Brindha, Karthikeyan | Jagadeshan, G. | Kalpana, L. | Elango, L.
Climatic condition, geology, and geochemical processes in an area play a major role on groundwater quality. Impact of these on the fluoride content of groundwater was studied in three regions-part of Nalgonda district in Telangana, Pambar River basin, and Vaniyar River basin in Tamil Nadu, southern India, which experience semi-arid climate and are predominantly made of Precambrian rocks. High concentration of fluoride in groundwater above 4 mg/l was recorded. Human exposure dose for fluoride through groundwater was higher in Nalgonda than the other areas. With evaporation and rainfall being one of the major contributors for high fluoride apart from the weathering of fluoride rich minerals from rocks, the effect of increase in groundwater level on fluoride concentration was studied. This study reveals that groundwater in shallow environment of all three regions shows dilution effect due to rainfall recharge. Suitable managed aquifer recharge (MAR) methods can be adopted to dilute the fluoride rich groundwater in such regions which is explained with two case studies. However, in deep groundwater, increase in fluoride concentration with increase in groundwater level due to leaching of fluoride rich salts from the unsaturated zone was observed. Occurrence of fluoride above 1.5 mg/l was more in areas with deeper groundwater environment. Hence, practicing MAR in these regions will increase the fluoride content in groundwater and so physica or chemical treatment has to be adopted. This study brought out the fact that MAR cannot be practiced in all regions for dilution of ions in groundwater and that it is essential to analyze the fluctuation in groundwater level and the fluoride content before suggesting it as a suitable solution. Also, this study emphasizes that long-term monitoring of these factors is an important criterion for choosing the recharge areas.
Show more [+] Less [-]Fluoride in weathered rock aquifers of southern India: Managed Aquifer Recharge for mitigation Full text
2016
Brindha, K. | Jagadeshan, G. | Kalpana, L. | Elango, L.
Climatic condition, geology, and geochemical processes in an area play a major role on groundwater quality. Impact of these on the fluoride content of groundwater was studied in three regions—part of Nalgonda district in Telangana, Pambar River basin, and Vaniyar River basin in Tamil Nadu, southern India, which experience semi-arid climate and are predominantly made of Precambrian rocks. High concentration of fluoride in groundwater above 4 mg/l was recorded. Human exposure dose for fluoride through groundwater was higher in Nalgonda than the other areas. With evaporation and rainfall being one of the major contributors for high fluoride apart from the weathering of fluoride rich minerals from rocks, the effect of increase in groundwater level on fluoride concentration was studied. This study reveals that groundwater in shallow environment of all three regions shows dilution effect due to rainfall recharge. Suitable managed aquifer recharge (MAR) methods can be adopted to dilute the fluoride rich groundwater in such regions which is explained with two case studies. However, in deep groundwater, increase in fluoride concentration with increase in groundwater level due to leaching of fluoride rich salts from the unsaturated zone was observed. Occurrence of fluoride above 1.5 mg/l was more in areas with deeper groundwater environment. Hence, practicing MAR in these regions will increase the fluoride content in groundwater and so physical or chemical treatment has to be adopted. This study brought out the fact that MAR cannot be practiced in all regions for dilution of ions in groundwater and that it is essential to analyze the fluctuation in groundwater level and the fluoride content before suggesting it as a suitable solution. Also, this study emphasizes that long-term monitoring of these factors is an important criterion for choosing the recharge areas.
Show more [+] Less [-]Fluoride in weathered rock aquifers of southern India: managed aquifer recharge for mitigation Full text
2016
Brindha, Karthikeyan | Jagadeshan, G. | Kalpana, L. | Elango, L.
Climatic condition, geology, and geochemical processes in an area play a major role on groundwater quality. Impact of these on the fluoride content of groundwater was studied in three regions-part of Nalgonda district in Telangana, Pambar River basin, and Vaniyar River basin in Tamil Nadu, southern India, which experience semi-arid climate and are predominantly made of Precambrian rocks. High concentration of fluoride in groundwater above 4 mg/l was recorded. Human exposure dose for fluoride through groundwater was higher in Nalgonda than the other areas. With evaporation and rainfall being one of the major contributors for high fluoride apart from the weathering of fluoride rich minerals from rocks, the effect of increase in groundwater level on fluoride concentration was studied. This study reveals that groundwater in shallow environment of all three regions shows dilution effect due to rainfall recharge. Suitable managed aquifer recharge (MAR) methods can be adopted to dilute the fluoride rich groundwater in such regions which is explained with two case studies. However, in deep groundwater, increase in fluoride concentration with increase in groundwater level due to leaching of fluoride rich salts from the unsaturated zone was observed. Occurrence of fluoride above 1.5 mg/l was more in areas with deeper groundwater environment. Hence, practicing MAR in these regions will increase the fluoride content in groundwater and so physica or chemical treatment has to be adopted. This study brought out the fact that MAR cannot be practiced in all regions for dilution of ions in groundwater and that it is essential to analyze the fluctuation in groundwater level and the fluoride content before suggesting it as a suitable solution. Also, this study emphasizes that long-term monitoring of these factors is an important criterion for choosing the recharge areas.
Show more [+] Less [-]