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Treatment of phthalic anhydride residue for improved handling and disposalVan Staden, Karen 31 October 2005 (has links)
The handling and disposal of hot tarry liquid residues can be problematic in industry, in this case, a phthalic anhydride plant using naphthalene as feed stock. The residue from the plant contains an appreciable amount of phthalic anhydride which desublimates from the residue during draining, resulting in an unsafe working environment. In addition, the residue is a hot liquid that solidifies upon cooling, causing additional risks to personnel during handling and various problems associated with disposal. Research was conducted into finding a treatment method to reduce or eliminate the desublimation of phthalic anhydride from the residue and addressing the hot liquid residue, making the residue safer to handle and easy to dispose of. Laboratory experiments showed that the addition of Dicalite 4151 (a filter aid) in a concentration of 0,3 kg Dicalite 4151 per kg phthalic anhydride residue, resulted in the formation of a powdered residue. This was confirmed during plant trials where using the same concentration proved that a powdered residue could be obtained, while at the same time desublimation of the phthalic anhydride from the residue was negated by distilling the product from the residue mixture. An opportunity exists to test the use of filter aid in other residue producing industries to determine if the same results can be achieved. / Dissertation (MEng (Environmental Engineering))--University of Pretoria, 2005. / Chemical Engineering / unrestricted
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Dietary intake patterns and relationships to polybrominated diphenyl ether (PBDE) and phthalate body burden.Colacino, Justin. Schecter, Arnold, Harris, T. Robert January 2009 (has links)
Source: Masters Abstracts International, Volume: 47-06, page: 3476. Adviser: Arnold J. Schecter. Includes bibliographical references.
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Uticaj ftalata iz spoljašnje sredine na neke metaboličke poremećaje / The influence of phthalates at environmental levels on certain metabolic disordersBosić-Živanović Dragana 30 September 2015 (has links)
<p>Uvod. Ftalati su endokrini disruptori, široko se koriste kao plastifikatori, rastvarači i aditivi u mnogim potrošačkim proizvodima. Eksperimentalni podaci i humane studije sugerišu na povezanost ftalata sa gojaznošću i dijabetesom. Cilj. Utvrditi da li su i koji urinami metaboliti ftalata prisutni i da li postoje razlike u njihovim nivoima između bolesnika s tipom 2 šećeme bolesti, gojaznih i kontrolne grupe zdravih osoba; da li postoji povezanost između metabolita ftalata i gojaznosti, lipida i lipoproteina seruma, glikemije, insulinemije i insulinske rezistencije.<br />Metode. Istraživanje je obuhvatilo 305 ispitanika, podeljenih u 3 grupe: gojazni (n=104), dijabetesni bolesnici tip 2 (n=101) i zdrave osobe (n=100), oba pola. U svih ispitanika su izvršena antropometrijska merenja (BMI i obim struka), određivanje serumskih lipida (ukupni holesterol, trigliceidi, HDL i LDL holesterol), te glikemija, insulinemija i izračunat indeks insulinske rezistencije (HOMA IRI). U jutarnjem uzorku urina meren je nivo 10 ftalatnih metabolita: mono-metil ftalat (MMP), mono-etil ftalat (MEP), mono-n-butil ftalat (MnBP), mono- benzil ftalat (MBzP), mono-cikloheksil ftalat (MCHP), mono-n-propil ftalat (MPP), mono-n-amil ftalat (MnAP), mono-izo-amil ftalat (MiAP), mono- n-oktil ftalat (MOP), mono-2-etilheksil ftalat (MEHP). U odnosu na prisustvo ftalata u urinu svaka grupa je podeljena u podgrupe na one sa prisutnim ftalatima i one bez ftalata u urinu, odnosno na podgrupe MEP pozitivne, MEP negativne, MEHP pozitivne i MEHP negativne. Rezultati. Kod polovine ispitanika registrovali smo prisustvo u urinu pojedinih metabolita ftalata. Najčešći su bili MEHP i MEP. Najveća sličnost u nivou MEP-a i MEHP-a je bila između gojaznih i dijabetesnih ispitanika. U odnosu na antropometrij ske parametre uočena je pozitivna korelacija MEP-a sa BMI i obimom struka, a negativna korelacija MEHP-a sa BMI i obimom struka, ali su bile nesignifikantne. Samo kod MEHP pozitivnih kontrolne grupe uočena je statistički značajna pozitivna korelacija MEHP-a i obima struka. Utvrđena je statistički značajna negativna korelaciju MEP-a i HDL holesterola, a pozitivna korelacija MEP-a i triglicerida samo kod gojaznih. Samo u kontrolnoj grupi MEHP pozitivnih postojala je statistički značajna negativna korelacija sa HDL holesterolom. Postojala je pozitivna korelacija MEP-a i HOMA-IRI, a pozitivna korelacija MEHP-a sa glikemijom samo kod MEHP pozitivnih DM tip 2. Zaključak. Potvrđeno je da je kontaminacija ftalatima prisutna u našoj populaciji, a najčešće su prisutni MEHP i MEP, ukazujući na ekspoziciju DEHP i DEP. Indirektno smo stekli uvid da povećana izloženost DEP i DEHP može doprineti nastanku izvesnih poremećaja lipida i lipoproteina, insulinskoj rezistenciji kao i razvoju gojaznosti.</p> / <p>Introduction. Phthalates are endocrine disruptors, widely used as plasticizers, solvents and additives in a wide range of consumer products. Experimental data and human studies suggest that phthalate exposure is linked with obesity and diabetes. Aim. To determine whether urinary phthalate metabolites are present, which ones are present, whether there are differences between their levels among the patients with type 2 diabetes, obesity patients and a control group of healthy individuals; whether there is a link between phthalate metabolites and obesity, lipids, serum lipoproteins, glycemia, insulinemia and insulin resistance. Methods. The research included 305 participants divided into three groups: obesity patients (n=104), type 2 diabetes patients (n=101) and healthy individuals (n=100) in both sexes. Anthropometric measurements were taken from all participants (BMI and waist circumference), as well as measurement of serum lipids (total cholesterol, triglycerides, HDL and LDL cholesterol), glycemia, insulinemia and a calculation of insulin resistance index (HOMA IRI). The levels of ten phthalate metabolites were<br />measured in a morning sample of urine: Mono-methyl phthalate (MMP), Mono-ethyl phthalate (MEP), Mono-n-butyl phthalate (MnBP), Mono-benzyl phthalate (MBzP), Mono- cyclohexyl phthalate (MCHP), Mono-n-propyl phthalate (MPP), Mono-n-amyl phthalate (MnAP), Mono-iso-amyl phthalate (MiAP), Mono-n-octyl phthalate (MOP), Mono-2- ethylhexyl phthalate (MEHP). Regarding the presence of phthalates in urine, each group was divided into subgroups, containing phthalates and or not containing phthalates, i.e. subgroups MEP positive and MEP negative, MEHP positive and MEHP negative. Results. In a half of participants, we have registered the presence of certain phthalate metabolites in urine, most often MEHP and MEP. The highest similarity in the levels of MEHP and MEP was between obesity and diabetes participants. Regarding anthropometric measurements, positive correlation has been registered between MEP and BMI and waist circumference, while negative correlation has been registered between MEHP and BMI and waist circumference, but it was insignificant. Only in MEHP positive control group, statistically significant positive correlation between MEHP and waist circumference has been registered. Statistically significant negative correlation between MEP and HDL cholesterol has been registered, while positive correlation between MEP and triglycerides has been registered only in obesity patients group. Only in MEHP positive control group statistically significant negative correlation with HDL cholesterol has been registered. There has been a positive correlation between MEP and HOMA-IRI, while positive correlation between MEHP and glycemia has been registered only in MEHP positive DM type 2. Conclusion. It has been confirmed that our population is contaminated with phthalates, most commonly MEHP and MEP, indicating exposure to DEHP and DEP. Indirectly, we have realized that an increased exposure to DEHP and DEP can contribute to the development of certain lipid and lipoprotein disorders, insulin resistance, as well as the development of obesity.</p>
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Povezanost estara ftalne kiseline i sindroma policističnih jajnika / Association between phthalic acid esters and polycystic ovarian syndromeMilankov Andrijana 14 March 2019 (has links)
<p>Uvod: Ftalati su vrsta endokrinih disruptora koji se široko koriste kao plastifikatori i rastvarači ali i kao aditivi brojim proizvodima koji se svakodnevno koriste. Prema dosadašnjim studijama na eksperimentalnim životinjama, ali i u humanoj populaciji, diestri ftalne kiseline utiču na reproduktivni sistem, učestvuju u nastanku insulinske rezistencije i gojaznosti. Sindrom policističnih ovarijuma (PCOS) je najčešći endokrinološki poremećaj reproduktivnog sistema žena u generativnom periodu. Insulinska rezistencija i centralna gojaznost, kao faktori kardiometaboličkog sindroma imaju značajnu ulogu u etiologiji PCOS. Ciljevi: Utvrditi prisustvo metabolita ftalne kiseline kod žena u reproduktivnom periodu u našoj sredini, kao i da li postoji povezanost ovih endokrinih disruptora sa antropometrijskim parametrima, parametrima glikoregulacije, lipidima i lipoproteinima seruma, gonadotropinima, polnim hormonima, leptinom i indeksima kardiometaboličkog rizika kod žena sa sindromom policističnih jajnika. Metode: Istraživanje je obuhvatalo 61 ženu sa sindromom policističnih jajnika koje su podeljene u dve podgrupe: 31 ispitanica sa PCOS i prisutnim ftalatnim metabolitima u urinu i 30 ispitanica sa PCOS bez ftalatnih metabolita u urinu. Kontrolnu grupu je činilo 30 zdravih žena. Kod svih ispitanica vršena su antropometrijska merenja (TV, TM, OS) i određivane vrednosti parametara glikoregulacije (glikemija i insulinemija, izačunat je HOMA index), lipidi i lipoproteini seruma (ukupan holesterol, trigliceridi, LDL i HDL holesterol), gonadotropini (LH i FSH), polni hormoni (estradiol i testosteron) i leptin. U proceni kardiometaboličkog rizika korišćena su dva indeksa LAP i VAI. Iz jutarnjeg uzorka urina određivano je prisustvo i koncentracija 10 ftalatnih metabolita: Mono-metil ftalat- MMP, Mono-etil ftalat - MEP, Mono-n-butil ftalat - MBP, Mono-n-propil ftalat- MPP, Mono-izo-amil ftalat - MiAP, Mono-n-amil ftalat - MnAP, Mono-cikloheksil ftalat - MCHP, Monobenzil ftalat- MBzP, Mono-(2-etilheksil) ftalat- MHEP, Mono-n-octil ftalat-MOP. Za statističku obradu podataka korišćeni su odgovarajući parametarski i neparametarski testovi. Rezultati: Kod 51 % ispitanica sa PCOS potvrđeno je prisustvo ftalatnih metabolita u urinu. Najzastupljeniji ftalatni metabolit je bio MEHP, zatim MEP, ali je potvrđeno i prisustvo MMP, MPP i MOP. Kod ispitanica sa PCOS su potvrđene statistički značajne korelacije između ukupnih ftalatnih metabolita i BMI, obima struka, glikemije, insulinemije, HOMA indeksa, ukupnog holesterola, triglicerida, LDL holesterola, leptina i testosterona. Analizom pojedinačnih ftalatnih metabolita utvrđene su pozitivne korelacije između MMP i obima struka, parametara glukoznog metabolizma, ukupnog holesterola, LDL holesterola, triglicerida, LAP i VAI indeksa. Zaključak: Kod žena sa PCOS u reproduktivnom periodu u našoj sredini je potvrđeno prisustvo ftalanih metabolita. Najviše koncentracije su verifikovane za MEHP i MEP, ukazujući na visoku ekspoziciju di-etilheksil ftalatu (DEHP) i di-etil ftalatu (DEP). Ukupni ftalati značajno povećavaju vrednosti parametara koje učestvuju u razvoju metaboličkog sindroma kod PCOS, ali i povećavaju kardiovaskularni rizik ovih bolesnica. Direktna, značajna veza je potvrđena između MMP i testosterona, parametara i indeksa kardiometaboličkog sindroma.</p> / <p>Introduction: Phthalates are a type of endocrine disruptor widely used as plasticizers and solvents but also as additives to many products that are used daily. According to previous studies in experimental animals, but also in the human population, phthalic diesters affect the reproductive system, participate in the onset of insulin resistance and obesity. Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder of the reproductive system of women in the generative period. Insulin resistance and central obesity, as factors of cardiometabolic syndrome, have a significant role in the etiology of PCOS. Objectives: To determine the presence of phthalic acid metabolites in women in the reproductive period in our environment, and whether there is a connection between these endocrine disruptors with anthropometric parameters, glycoregulation parameters, lipids and serum lipoproteins, gonadotrophins, sex hormones, leptin and indexes of cardiometabolic risk in women with polycystic ovarian syndrome. Methods: The study included 61 women with polycystic ovarian syndrome divided into two subgroups: 31 subjects with PCOS and present phthalate metabolites in urine and 30 subjects with PCOS without phthalate metabolites in urine. The control group consisted of 30 healthy women. In all subjects, anthropometric measurements were carried out (TV, TM, WC) and the values of glycoregulation parameters (glycemia and insulinemia, HOMA index), lipids and serum lipoproteins (total cholesterol, triglycerides, LDL I HDL cholesterol), gonadotropins FSH), sex hormones (estradiol and testosterone) and leptin. In the assessment of cardiometabolic risk LAP and VAI indexes were determined. From the morning urine sample, the presence and concentration of 10 phthalate metabolites were determined: Mono-methyl phthalate-MMP, Mono-ethyl phthalate-MEP, Mono-n-butyl phthalate-MBF, Mono-n- propyl phthalate- MPP, Mono-iso-amyl phthalate – MiAP, Mono-n-amyl phthalate – MnAP, Mono-cyclohexyl phthalate-MCHP, Monobenzyl phthalate-MBzP, Mono- (2-ethylhexyl) phthalate-MHEP, Mono-n-octyl phthalate-MOP. For statistical data processing, appropriate parametric and non-parametric tests were used. Results: 51% of subjects with PCOS confirmed the presence of phthalate metabolites in urine. The most common phthalate metabolite was MEHP, then MEP, but the presence of MMP, MPP and MOP also was confirmed. In subjects with PCOS, a statistically significant correlations between total phthalate metabolites and BMI, waist circumference, glycemia, insulinemia, HOMA index, total cholesterol, triglyceride, LDL cholesterol, leptin and testosterone were confirmed. By analyzing individual phthalate metabolites, a positive correlations between MMP and waist circumference, glycoregulation parameters, total cholesterol, LDL cholesterol, triglyceride, testosterone and LAP and VAI index were determined. Conclusion: In women with PCOS in the reproductive period, the presence of phthalic metabolites in our environment was confirmed. The highest concentrations were verified for MEHP and MEP, indicating a high exposure of DEHP and DEP. Total phthalates significantly increase the values of parameters involved in the development of metabolic syndrome in PCOS, but also increase the cardiovascular risk of these patients. A direct, significant association was confirmed between MMP and testosterone, parameters and index of cardiometabolic syndrome.</p>
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Systematic identification of thermal degradation products of HPMCP during hot melt extrusion processKarandikar, Hrushikesh M., Ambardekar, Rohan, Kelly, Adrian L., Gough, Tim, Paradkar, Anant R January 2015 (has links)
No / A systematic identification of the degradation products of hydroxypropyl methylcellulose phthalate (HPMCP) during hot melt extrusion (HME) has been performed. A reverse phase HPLC method was developed for the extrudates of both hydroxypropyl methylcellulose acetate succinate (HPMCAS) and HPMCP polymers to quantify their thermal hydrolytic products: acetic acid (AA), succinic acid (SA) for HPMCAS and phthalic acid (PA) for HPMCP, without hydrolysing the polymers in strong alkaline solutions. The polymers were extruded in the temperature range of 160-190 degrees C at different screw rotation speeds and hydrolytic impurities were analysed. Investigation of extruded HPMCP showed an additional thermal degradation product, who is structural elucidation revealed to be phthalic anhydride (PAH). Moreover, two environmental analytical impurities, dimethyl phthalate and methyl benzoate formed in situ were recorded on GC-MS and their origin was found to be associated with PAH derivatization. Using the experimental data gathered during this study, a degradation mechanism for HPMCP is proposed.
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Uticaj estara ftalne kiseline na tiroidnu funkciju / The influence of phthalic acid esters on thyroid functionBajkin Ivana 20 May 2016 (has links)
<p>Uvod: Poslednjih godina u fokusu istraživača je efekat sintetskih jednjenja na endokrini sistem. Estri ftalne kiseline se koriste u procesu plastifikacije, kao industrijski rastvarači, lubrikanti, aditivi u tekstilnoj industriji, u pesticidima, kozmetičkim proizvodima. Raste broj dokaza da je tiroidna žlezda podložna dejstvu endokrinih disruptora. Tiroidni hormoni imaju važnu ulogu u regulaciji rasta, tkivne diferencijacije, energetskog metabolizma, reprodukcije i formiranja centralnog nervnog sistema. Brojna istraživanja ukazala su da ftalati deluju kao EDs. Ciljevi istraživanja: 1. Procena izloženosti populacije mono-etilheksil-ftalatu (MEHP) i mono-etil-ftalatu (MEP). 2. Evaluacija razlika u nivou pokazatelja tirodine funkcije između ftalat pozitivnih i ftalat negativnih ispitanika i između gojaznih i normalno uhranjenih ftalat pozitivnih ispitanika. 3.Utvrđivanje razlika u serumskom nivou leptina gojaznih ispitanika sa i bez pozitivnih ftalatnih metabolita i procena povezanosti leptina sa MEP i MEHP i pokazateljima tiroidne funkcije. Izbor ispitanika i metod rada: Istraživanje je sprovedeno kao studija preseka, obuhvatilo je 201 ispitanika. Ispitanici su podeljeni u grupu MEP/MEHP pozitivnih i negativnih i na podgupe normalno uhranjenih i gojaznih. Od antropometrijskih mera određena je telesna visina, telesna masa, obim struka i indeks telesne mase. Laboratorijske analize: jutarnji uzorak urina za određivanje MEP i MEHP; našte uzet uzorka venske krvi za FT4, FT3, TSH i leptin. Statististička analiza sprovedena je na softverskom paketu SPSS. Rezultati: Polovina stanovništva je izložena ftalatima. MEP dovodi do povišenja FT4 samo u subpopulaciji gojaznih. Nije utvrđen statistički značajan uticaj MEP na FT3. Kod gojaznih MEP pozitivnih osoba ženskog pola povišen je TSH. MEHP uzrokuje sniženje FT4 kod normalno uhranjenih ispitanika, a kod normalno uhranjenih muškaraca snižava FT3. Nije utvrđen uticaj MEHP na tirotropin. U gojaznih nije ustanovljen uticaj DEHP i DEP na leptinsku sekreciju.Uočena je tendencija negativne korelacije leptina i FT4 kod gojaznih, dok uticaja na FT3 i TSH nema. Zaključak: Naša populacija je u velikoj meri izložena ftalatima. Potvrđeno je da MEP i MEHP imaju uticaj na pojedine indikatore tiroidne funkcije. Ftalati u našem istraživanju ne uzrokuju poremećaj leptinske skrecije, a leptin ima blag uticaj jedino na FT4.</p> / <p>Introduction: Effects of synthesized chemicals on endocrine system has been in the focus in the last years. Phthalates are used in plasticization, as industrial solvents, lubricants, textile industry additives, in pesticides and cosmetic products. Evidence for thyroid disruption is growing. Thyroid hormones (TH) have an important role in regulation of growth, tissue differentiation, energy metabolism, reproduction and central nervous system formation. Studies show phthalates can cause endocrine disruption. Aims: 1. Estimation of burden of mono-ethyl phthalate (MEP) and di-2-ethylheksyl phthalate(MEHP) in the population. 2. Evaluation of differences in TH and TSH in MEP/MEHP positive and negative participants, as in obese and lean MEP/MEHP positive participants. 3. Evaluation of differences in leptin in obese MEP/MEHP positive and negative subjects and evaluation of the connection between leptin, MEP, MEHP and thyroid indicators. Patients and methods: This was a cross-sectional study that comprised 201 subjects divided into MEP/MEHP positive and negative group, further subdivided in obese and lean. Anthropometric parameters done: body height, body weight, waist and body mass index. Laboratory tests done: morning urine sample analysis for MEP/MEHP and venous sample analysis for free thyroxine (FT4), free tri-iodothyronine (FT3), thyroid stimulating hormone (TSH) and leptin. Statistical analysis was done in SPSS. Results: Half of subjects were exposed to phthalates. MEP induced an increase in FT4 in obese participants and had no influence on FT3. TSH was increased in obese MEP positive female subjects. MEHP induced a decrease in FT4 in lean participants and a decrease of FT3 in lean males. There was no correlation between MEHP and TSH. Influence of MEP/MEHP on leptin secretion. A tendency for negative correlation between leptin and FT4 was seen. There was no influence of leptin on FT3 and TSH. Conclusion: Our population is greatly exposed to phthalates. MEP and MEHP influence certain thyroid indicators i.e. cause thyroid disruption. Phthalates do not influence leptin secretion in our study. There is a mild effect of leptin on FT4.</p>
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