The thesis on the topic Soil pollution by phthalic acid esters in Czech Republic solves the problem of soil pollution by dibutyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP). This thesis joined the annual monitoring conducted by Central Control and Testing Institute of Agriculture. The monitoring of contaminants was carried in twelve regions of the Czech Republic. The samples do represent different types of culture farmland. They were formed by arable land, permanent grassland and hop-garden. Before the analysis, the samples were extracted with acetone-hexane mixture with 1:1 ratio, and ultrasound. Samples were analyzed by liquid chromatography with UV detection. The measured concentrations for the year 2016 ranged in DBP from 0.07 to 0.21 mg.kg-1 dry weight, at DEHP from 0.19 to 1.08 mg.kg-1 dry weight, esters together from 0.13 to 0.65 mg.kg-1.

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Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal. / Le but de cette étude était de vérifier l'applicabilité de la définition classique de la dysplasie bronchopulmonaire (DBP) chez les enfants extrêmement prématurés en déterminant si les enfants oxygénodépendants à 28 jours et plus de vie, mais non à 36 semaines de gestation, seront plus à risque de morbidité à 18 mois que les enfants sans DBP. La population était constituée de 217 enfants, nés dans un centre tertiaire à 24-28 semaines de gestation, entre 1987 et 1992, et classifiés en 3 groupes : groupe de comparaison (C) : O₂ ≤ 28 jours de vie (n = 76) ; DBP-1 : O₂ > 28 jours et < 36 semaines d'âge gestationnel (n = 48) ; et DBP-2 : O₂ ≥ 36 semaines (n = 93). Les mesures étudiées étaient la croissance, les problèmes respiratoires persistants (asthme, trachéostomie, oxygène à la maison), les chirurgies, les réhospitalisations, l'état neurologique et le développement à 18 mois. Résultats : Aucune différence de poids, de taille et de périmètre crânien n'a été trouvée entre les 3 groupes. Il n'y avait pas de différence dans le nombre de jours de réhospitalisation pour toutes causes, dans le nombre de jours de réhospitalisation aux soins intensifs et pour le taux de problèmes respiratoires permanents. Les enfants du groupe DBP-2 ont eu davantage de jours de réhospitalisation pour des causes pulmonaires en comparaison aux deux autres groupes (C : 2.0 vs DBP-1 : 2.0 vs DBP-2 : 6.3 (DBP-1 vs DBP-2 : p < .05)). Ils ont aussi eu plus souvent besoin d'herniotomies (C : 9 % vs DBP-1 : 5 % vs DBP-2 : 18 %, p < .01), mais il n'y avait aucune différence au niveau des chirurgies otorhinolaryngologiques. Le quotient de développement moyen des enfants du groupe DBP-2 était inférieur (C : 97.4 ± 15.0 vs DBP-1 : 97.9 ± 11.6 vs DBP-2 : 90.7 ± 19.3, p < .05). Il n'y avait aucune différence dans le taux de paralysie cérébrale ou de déficits sensoriels. La présence de lésions cérébrales sévères, une adversité familiale élevée et une ventilation prolongée étaient les facteurs qui influençaient le plus le devenir des enfants. Conclusion : Les enfants du groupe DBP-1 sont similaires à ceux du groupe de comparaison à tous les niveaux. Les enfants du groupe DBP-2 sont identiques à ceux des autres groupes pour la croissance, la santé et le statut neurologique, mais diffèrent par un nombre supérieur de jours de réhospitalisation pour des problèmes pulmonaires, un besoin plus grand d'herniotomies et davantage de retards de développement. Pour les enfants nés très prématurément, nous favorisons l'utilisation d'une dépendance à l'oxygène à 36 semaines d'âge gestationnel au lieu de 28 jours de vie pour identifier les enfants à risque.

The thesis on the topic "The analysis of phthalic acid esters in agricultural soils in the Czech Republic" describes the properties of phthalic acid esters, the occurrence and the negative effects related to the environment and human health. The aim of this diploma thesis was to monitor phthalic acid esters, especially di-2- (ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) in agricultural soil samples. Monitoring of phthalates was carried out in cooperation with the Central Control and Testing Institute of Agriculture in Brno as part of their annual monitoring of phthalates and other organic contaminants in soils. During March 2018, a total of 40 soil samples were collected in 12 regions of the Czech republic. Before phthalate analysis, samples were extracted with a mixture of acetone-hexane (1:1). Using ultrasound was performed using high performance liquid chromatography with UV detection. Determined concentrations for DBP were from 0.13 to 1.07 mg.kg-1 dry weight and for DEHP from 0.13 to 1.02 mg.kg-1 dry weight.

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Landfilling is the most common approach to dispose of municipal solid wastes but inevitably leads to leachate formation. Persistent UV quenching substances (UVQS) in landfill leachate can affect the effectiveness of UV disinfection in municipal wastewater treatment systems when leachate co-treatment is applied. Membrane electrochemical reactor (MER) treatment was investigated to reduce the UV quenching capability and simultaneously recover resources in the leachate as an effective onsite pre-treatment. Ion-selective membranes were used in this MER to create two different conditions: a low-pH anolyte for organic oxidation and a high-pH catholyte for ammonia recovery. The MER achieved significantly higher removals of both dissolved organic carbon and UV254nm absorbance than membrane-less electrochemical treatment. The MER was able to remove a large percentage of total nitrogen from the leachate while recovering about half of the influent ammonia in the catholyte with less specific energy consumption. The second study coupled MER with Fenton oxidation through providing synergistic benefits with the low solution pH, reduced organics, and ammonia removal. This two-stage coupled system reduced the more leachate COD than the standalone Fenton process treating raw leachate. Also, the usage of chemicals as Fenton reagents has been greatly reduced: FeSO4 and H2O2 by 39%, H2SO4 by 100%, and NaOH by 55%. Consequently, the sludge production was reduced by 51% in weight and 12% in volume. Despite electricity consumption by the MER, the coupled system cost $4.76 per m3 leachate less than the standalone Fenton treatment. More notably, direct Fenton oxidation removed only 21% of ammonia; in comparison, the MER-Fenton system removed ammonia by 98% with the possibility for recovery at a rate of 30.6 -55.2 kg N m-3 reactor d-1. Those results demonstrated that coupling MER with the Fenton process could mitigate some inherent drawbacks of Fenton oxidation such as ineffective ammonia removal, high acid and chemical reagents dose requirements, and a large amount of sludge generation. The third study investigated the formation of total halogenated organics (DBP) and the associated toxicity as the side effect of leachate treatment in the MER. Compared to the 4538±100 µg L-1 from the control membrane-less electrochemical oxidation reactor, the amount of DBP generated in the MER only accounted for 19.1±4.5 % after the same treatment period. The total toxicity value (26.6 ×10-3 ) was low for MER effluent, only 15.1% of that in the control group. Both high pH and high ammonia concentration introduced more DBP mass and toxicity production after MER treatment. DBP concentrations were shown to increase with applied current density and possible temperature raise. With 67.5% of DBP mass concentration and 74.4% of the additive toxicity removal, the granular activated carbon (GAC) electrode system was shown more effective than GAC adsorption alone in remediating DBP harmful effects. This dissertation introduced MER as a promising technology for the treatment of leachate through performance demonstration, process integration and by-product remediation. / Doctor of Philosophy / Municipal solid waste is often disposed of in landfills because of the most economics and convenience. However, one of the most challenging problems is the leachate formation and treatment. In the US, leachate is currently often diluted in domestic wastewater treatment systems; meanwhile, the persistent contaminants in landfill leachate can lower the effectiveness of UV disinfection and result in high cost and permit violation. In this study, the membrane electrochemical reactor (MER) using electricity as the driving force was applied to solve the issue and simultaneously recover valuable resources in the leachate. Membranes as a barrier for selective ions were used in this MER to create two different conditions with different purposes: a low-pH anolyte for organic oxidation and a high-pH catholyte for ammonia recovery. The MER achieved significantly higher contaminants removals than membrane-less electrochemical treatment. The second study coupled MER with one of the established advanced oxidation processes, also known as Fenton oxidation through providing mutual benefits with the low solution pH, reduced organics, and ammonia removal/recovery. This two-stage coupled system reduced the leachate contaminants effectively towards the direct discharge standard. In addition, the usage of chemical reagents, as well as the amount of process residual, has significantly been reduced. The third study investigated the formation of by-products as the side effect of leachate treatment in the MER. Compared to the membrane-less reactor, the undesirable by-products generated in the MER only accounted for one fifth after the same treatment period. A granular activated carbon electrode system was shown effective in remediating the harmful effects. This dissertation introduced MER as a promising technology for the treatment of leachate as one of the toughest wastewaters.