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Kurunthachalam Kannan - One of the best experts on this subject based on the ideXlab platform.
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phthalates bisphenols Parabens and triclocarban in feminine hygiene products from the united states and their implications for human exposure
Environment International, 2020Co-Authors: Kurunthachalam KannanAbstract:Abstract Feminine hygiene products, a category of daily necessities, can be a source of exposure to plasticizers and antimicrobial agents in women. Nevertheless, studies on the occurrence of chemicals in feminine hygiene products have received little attention. In this study, 24 endocrine-disrupting chemicals (EDCs), comprising nine phthalates, six Parabens, eight bisphenols, and triclocarban (TCC) were measured in seven categories of feminine hygiene products (i.e., pads, panty liners, tampons, wipes, bactericidal creams and solutions, and deodorant sprays and powders; N = 77) collected in the Albany area of New York State in the United States. DimEthyl phthalate (DMP), diEthyl phthalate (DEP), dibutyl phthalate (DBP), di-iso-butyl phthalate (DIBP), di(2-Ethylhexyl) phthalate (DEHP), mEthyl Paraben (MeP), and Ethyl Paraben (EtP) were found in all pad, panty liner, and tampon samples. Panty liners contained the highest concentrations of DMP (median: 249 ng/g), DEP (386 ng/g), DBP (393 ng/g), and DIBP (299 ng/g) and tampons contained the highest concentrations of DEHP (267 ng/g). MeP, EtP, and propyl Paraben (PrP) were the major Parabens found in feminine hygiene products. Bactericidal creams and solutions contained median concentrations of MeP, EtP and PrP at 2840, 734, and 278 ng/g, respectively. The estimated exposure doses of phthalates, Parabens, and bisphenols through the dermal absorption pathway from the use of pads, panty liners, and tampons were significant. In comparison with the exposure doses reported previously from other sources and pathways, the significance of feminine hygiene products as sources of EDC exposure was delineated. The dermal absorption doses from the use of feminine hygiene products, under different exposure scenarios, were 0.19–27.9% and 0.01–6.2% of the total exposure doses of phthalates and bisphenols, respectively. This is the first study to report the occurrence of phthalates, Parabens, bisphenols, and TCC in feminine hygiene products from the United States.
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advanced data mining approaches in the assessment of urinary concentrations of bisphenols chlorophenols Parabens and benzophenones in brazilian children and their association to dna damage
Environment International, 2018Co-Authors: Kurunthachalam Kannan, Masato Honda, Alexandros G Asimakopoulos, Bruno Alves Rocha, Nattane Luiza Da Costa, Rommel M Barbosa, Fernando BarbosaAbstract:Abstract Human exposure to endocrine disrupting chemicals (EDCs) has received considerable attention over the last three decades. However, little is known about the influence of co-exposure to multiple EDCs on effect-biomarkers such as oxidative stress in Brazilian children. In this study, concentrations of 40 EDCs were determined in urine samples collected from 300 Brazilian children of ages 6–14 years and data were analyzed by advanced data mining techniques. Oxidative DNA damage was evaluated from the urinary concentrations of 8-hydroxy-2′-deoxyguanosine (8OHDG). Fourteen EDCs, including bisphenol A (BPA), mEthyl Paraben (MeP), Ethyl Paraben (EtP), propyl Paraben (PrP), 3,4-dihydroxy benzoic acid (3,4-DHB), mEthyl-protocatechuic acid (OH-MeP), Ethyl-protocatechuic acid (OH-EtP), triclosan (TCS), triclocarban (TCC), 2-hydroxy-4-methoxybenzophenone (BP3), 2,4-dihydroxybenzophenone (BP1), bisphenol A bis(2,3-dihydroxypropyl) glycidyl ether (BADGE·2H2O), 2,4-dichlorophenol (2,4-DCP), and 2,5-dichlorophenol (2,5-DCP) were found in >50% of the urine samples analyzed. The highest geometric mean concentrations were found for MeP (43.1 ng/mL), PrP (3.12 ng/mL), 3,4-DHB (42.2 ng/mL), TCS (8.26 ng/mL), BP3 (3.71 ng/mL), and BP1 (4.85 ng/mL), and exposures to most of which were associated with personal care product (PCP) use. Statistically significant associations were found between urinary concentrations of 8OHDG and BPA, MeP, 3,4-DHB, OH-MeP, OH-EtP, TCS, BP3, 2,4-DCP, and 2,5-DCP. After clustering the data on the basis of i) 14 EDCs (exposure levels), ii) demography (age, gender and geographic location), and iii) 8OHDG (effect), two distinct clusters of samples were identified. 8OHDG concentration was the most critical parameter that differentiated the two clusters, followed by OH-EtP. When 8OHDG was removed from the dataset, predictability of exposure variables increased in the order of: OH-EtP > OH-MeP > 3,4-DHB > BPA > 2,4-DCP > MeP > TCS > EtP > BP1 > 2,5-DCP. Our results showed that co-exposure to OH-EtP, OH-MeP, 3,4-DHB, BPA, 2,4-DCP, MeP, TCS, EtP, BP1, and 2,5-DCP was associated with DNA damage in children. This is the first study to report exposure of Brazilian children to a wide range of EDCs and the data mining approach further strengthened our findings of chemical co-exposures and biomarkers of effect.
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Parabens in human urine from several asian countries greece and the united states
Chemosphere, 2018Co-Authors: Masato Honda, Kurunthachalam Kannan, Morgan RobinsonAbstract:Abstract Parabens, esters of para-hydroxybenzoic acid, are commonly used as antimicrobial preservatives in cosmetics and personal care products. Although several studies report exposure of humans to Parabens in Western countries, little is known about exposure of humans to Parabens in Asian countries. In this study, we determined concentrations of six Parabens in spot urine samples collected from nine countries and estimated daily intakes (DI) and potential health risks of Parabens. Ethyl-Paraben, mEthyl-Paraben, and propyl-Paraben were detected frequently at 100, 98.0, and 80.3%, respectively, with representative median concentrations of 0.68, 7.02, and 1.21 ng/mL, respectively, for all nine countries. Urine samples from females (total median concentration: 32.3 ng/mL) contained significantly higher concentrations of Parabens than did those from males (5.46 ng/mL). Urine samples from Korea (total median Paraben concentration: 227 ng/mL) had the highest concentrations, which were one to two orders of magnitude higher than those found in other countries (3.67–29.1 ng/mL). The estimated DI of Parabens (on the basis of concentrations measured in urine) varied widely, and several samples had propyl-Paraben exposures above the acceptable DI. Our results suggest that Paraben exposure is ubiquitous in Asian countries, and further assessment of potential health risk of these chemicals is needed.
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Elevated Concentrations of Bisphenols, Benzophenones, and Antimicrobials in Pantyhose Collected from Six Countries
2018Co-Authors: Kurunthachalam KannanAbstract:Pantyhose, a skin-tight item of clothing made of synthetic fibers and worn by women in many countries, is a source of exposure to several endocrine-disrupting chemicals. Little is known regarding the occurrence of and dermal exposure to chemicals present in pantyhose. In this study, concentrations and profiles of 23 endocrine-disrupting chemicals, including bisphenols, benzophenones, chlorophenols, Parabens, and triclocarban (TCC), were determined in 74 pantyhose samples collected from 6 countries. Pantyhose samples were analyzed by two extraction methods: complete dissolution and ultrasonic extraction. Dissolution of the fabric in 1,1,1,3,3,3-hexafluoro-2-propanol/chloroform yielded concentrations of several target chemicals that were up to 286 times higher than in the ultrasonic extraction. Bisphenol S (BPS) and bisphenol A (BPA) were found in 100% and 96% of the samples at median concentrations of 1430 and 14.3 ng/g, respectively. Several brands of pantyhose contained BPS, bisphenol F (BPF), benzophenone-1 (BP-1), Ethyl-Paraben (EtP), and TCC at concentrations of milligrams per gram. Benzophenone-3 (BP-3), 4-hydroxy benzoic acid (4-HB), and mEthyl- (MeP) and propyl-Parabens (PrP) were found in ≥85% of the samples at median concentrations on the order of several tens to hundreds of nanograms per gram of fabric. Pantyhose made in Japan and China with 21–50% Spandex contained the highest concentrations of BPS (2.2 mg/g), BP-1 (2.4 mg/g), and EtP (88 μg/g). Calculated dermal exposure doses to BPS, BP-1, and EtP by women via pantyhose were as high as 45 900, 50 600, and 1800 picograms per kilogram of body weight per day, respectively
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urinary levels of endocrine disrupting chemicals including bisphenols bisphenol a diglycidyl ethers benzophenones Parabens and triclosan in obese and non obese indian children
Environmental Research, 2015Co-Authors: Jingchuan Xue, Kurunthachalam Kannan, Sivasubramanian Sakthivel, Praveen V Pavithran, Jayakumar R VasukuttyAbstract:Obesity has been recognized as a major global public health concern. In particular, childhood obesity is a major risk factor for other health issues, such as type 2 diabetes, in later stages of life. A few earlier studies have associated exposure to endocrine-disrupting chemicals (EDCs) with childhood obesity. There is limited information, however, on exposure to EDCs and childhood obesity in India. In this study, urinary levels of 26 EDCs were determined in 49 obese and 27 non-obese Indian children. Eleven EDCs, including 2,2-bis(4-hydroxyphenyl)propane (BPA), 4,4′-sulfonyldiphenol (BPS), mEthyl Paraben (MeP), Ethyl Paraben (EtP), propyl Paraben (PrP), 4-hydroxybenzoic acid (4-HB), 3,4-dihydroxybenzoic acid (3,4-DHB), triclosan (TCS), benzophenone-3 (BP3), bisphenol A diglycidyl ether (BADGE), and bisphenol A bis(2,3-dihydroxypropyl) glycidyl ether (BADGE·2H2O) were found in >70% of urine samples. No significant associations were found between childhood obesity and most target chemicals studied, except for 3,4-DHB, which showed a significant positive association. Urinary concentrations of 3,4-DHB were higher in obese children than in non-obese children, independent of age, sex, family income, parent education, physical activity, and urinary creatinine. Urinary concentrations of several EDCs were higher in Indian children than the concentrations reported for children in the USA and China. To our knowledge, this is the first study to report urinary concentrations of several EDCs in Indian children.
Alexandros G Asimakopoulos - One of the best experts on this subject based on the ideXlab platform.
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advanced data mining approaches in the assessment of urinary concentrations of bisphenols chlorophenols Parabens and benzophenones in brazilian children and their association to dna damage
Environment International, 2018Co-Authors: Kurunthachalam Kannan, Masato Honda, Alexandros G Asimakopoulos, Bruno Alves Rocha, Nattane Luiza Da Costa, Rommel M Barbosa, Fernando BarbosaAbstract:Abstract Human exposure to endocrine disrupting chemicals (EDCs) has received considerable attention over the last three decades. However, little is known about the influence of co-exposure to multiple EDCs on effect-biomarkers such as oxidative stress in Brazilian children. In this study, concentrations of 40 EDCs were determined in urine samples collected from 300 Brazilian children of ages 6–14 years and data were analyzed by advanced data mining techniques. Oxidative DNA damage was evaluated from the urinary concentrations of 8-hydroxy-2′-deoxyguanosine (8OHDG). Fourteen EDCs, including bisphenol A (BPA), mEthyl Paraben (MeP), Ethyl Paraben (EtP), propyl Paraben (PrP), 3,4-dihydroxy benzoic acid (3,4-DHB), mEthyl-protocatechuic acid (OH-MeP), Ethyl-protocatechuic acid (OH-EtP), triclosan (TCS), triclocarban (TCC), 2-hydroxy-4-methoxybenzophenone (BP3), 2,4-dihydroxybenzophenone (BP1), bisphenol A bis(2,3-dihydroxypropyl) glycidyl ether (BADGE·2H2O), 2,4-dichlorophenol (2,4-DCP), and 2,5-dichlorophenol (2,5-DCP) were found in >50% of the urine samples analyzed. The highest geometric mean concentrations were found for MeP (43.1 ng/mL), PrP (3.12 ng/mL), 3,4-DHB (42.2 ng/mL), TCS (8.26 ng/mL), BP3 (3.71 ng/mL), and BP1 (4.85 ng/mL), and exposures to most of which were associated with personal care product (PCP) use. Statistically significant associations were found between urinary concentrations of 8OHDG and BPA, MeP, 3,4-DHB, OH-MeP, OH-EtP, TCS, BP3, 2,4-DCP, and 2,5-DCP. After clustering the data on the basis of i) 14 EDCs (exposure levels), ii) demography (age, gender and geographic location), and iii) 8OHDG (effect), two distinct clusters of samples were identified. 8OHDG concentration was the most critical parameter that differentiated the two clusters, followed by OH-EtP. When 8OHDG was removed from the dataset, predictability of exposure variables increased in the order of: OH-EtP > OH-MeP > 3,4-DHB > BPA > 2,4-DCP > MeP > TCS > EtP > BP1 > 2,5-DCP. Our results showed that co-exposure to OH-EtP, OH-MeP, 3,4-DHB, BPA, 2,4-DCP, MeP, TCS, EtP, BP1, and 2,5-DCP was associated with DNA damage in children. This is the first study to report exposure of Brazilian children to a wide range of EDCs and the data mining approach further strengthened our findings of chemical co-exposures and biomarkers of effect.
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widespread occurrence of bisphenol a diglycidyl ethers p hydroxybenzoic acid esters Parabens benzophenone type uv filters triclosan and triclocarban in human urine from athens greece
Science of The Total Environment, 2014Co-Authors: Nikolaos S Thomaidis, Alexandros G Asimakopoulos, Kurunthachalam KannanAbstract:Biomonitoring of human exposure to bisphenol A diglycidyl ethers (BADGEs; resin coating for food cans), p-hydroxybenzoic acid esters (Parabens; preservatives), benzophenone-type UV filters (BP-UV filters; sunscreen agents), triclosan (TCS; antimicrobials), and triclocarban (TCC; antimicrobials) has been investigated in western European countries and North America. Nevertheless, little is known about the exposure of Greek populations to these environmental chemicals. In this study, 100 urine samples collected from Athens, Greece, were analyzed by liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the determination of total concentrations of five derivatives of BADGEs, six Parabens and their metabolite (Ethyl-protocatechuate), five derivatives of BP-UV filters, TCS, and TCC. Urinary concentrations of BADGEs, Parabens, Ethyl-protocatechuate, BP-UV filters, TCS and TCC (on a volume basis) ranged 0.3–20.9 (geometric mean: 0.9), 1.6–1010 (24.2), < 2–71.0 (2.1), 0.5–1120 (4.4), < 0.5–2580 (8.0) and < 0.5–1.9 (0.6) ng/mL, respectively. All 19 target chemicals were found in urine, and the highest detection rates were observed for mEthyl Paraben (100%), bisphenol A bis (2,3-dihydroxypropyl) ether (90%), Ethyl Paraben (87%), 2,4-dihydroxybenzophenone (78%), propyl Paraben (72%), and TCS (71%). Estimated daily intakes (EDIurine), calculated on the basis of the measured urinary concentrations, ranged from 0.023 μg/kg bw/day for Σ5BADGEs to 31.4 μg/kg bw/day for Σ6Parabens.
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a multi class bioanalytical methodology for the determination of bisphenol a diglycidyl ethers p hydroxybenzoic acid esters benzophenone type ultraviolet filters triclosan and triclocarban in human urine by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2014Co-Authors: Alexandros G Asimakopoulos, Lei Wang, Nikolaos S Thomaidis, Kurunthachalam KannanAbstract:Abstract A liquid–liquid extraction (LLE; Ethyl acetate) protocol, followed by liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS) methodology, was developed for the determination of 19 compounds, including bisphenol A diglycidyl ethers (BADGEs; industrial ethers), benzophenone-type UV filters (BP-UV filters; precursors and metabolites), p-hydroxybenzoic acid esters (Parabens; preservatives), triclosan (TCS) and triclocarban (TCC) in human urine. Urine specimens were enzymatically deconjugated with β-glucuronidase (from Helix pomatia) and extracted by a LLE procedure for the measurement of total concentrations (i.e., free + conjugated forms) of target analytes. Absolute recoveries of BADGEs, BP-UV filters, Parabens, TCS and TCC ranged 25–135%, 84–125%, 52–126%, 75–118% and 90–124%, respectively. Method precision (absolute values; N = 5 replicate analyses at the fortification level of 10 ng, k = 5 days) ranged from 5.8 (Ethyl Paraben) to 24.0% (TCS). The limits of quantification (LOQs) varied depending on the target compound and generally ranged from 0.2 to 2.0 ng/mL. The matrix effects ranged from +11 (2,3,4-trihydroxybenzophenone) to −86% (2,4-dihydroxybenzophenone). A total of 30 urine specimens collected from Athens, Greece, were analyzed for the 19 target compounds to demonstrate the applicability of the developed method. The concentrations of target chemicals in urine were presented on volume-, specific gravity (SG)-, and creatinine-normalization bases. MeP, EtP, PrP, OH-EtP, BADGE·2H2O, BP-1 and TCS were found frequently in urine at concentrations in the range of 2.7–436 ng/mL,
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a multi class bioanalytical methodology for the determination of bisphenol a diglycidyl ethers p hydroxybenzoic acid esters benzophenone type ultraviolet filters triclosan and triclocarban in human urine by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2014Co-Authors: Alexandros G Asimakopoulos, Lei Wang, Nikolaos S Thomaidis, Kurunthachalam KannanAbstract:A liquid-liquid extraction (LLE; Ethyl acetate) protocol, followed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) methodology, was developed for the determination of 19 compounds, including bisphenol A diglycidyl ethers (BADGEs; industrial ethers), benzophenone-type UV filters (BP-UV filters; precursors and metabolites), p-hydroxybenzoic acid esters (Parabens; preservatives), triclosan (TCS) and triclocarban (TCC) in human urine. Urine specimens were enzymatically deconjugated with β-glucuronidase (from Helix pomatia) and extracted by a LLE procedure for the measurement of total concentrations (i.e., free+conjugated forms) of target analytes. Absolute recoveries of BADGEs, BP-UV filters, Parabens, TCS and TCC ranged 25-135%, 84-125%, 52-126%, 75-118% and 90-124%, respectively. Method precision (absolute values; N=5 replicate analyses at the fortification level of 10 ng, k=5 days) ranged from 5.8 (Ethyl Paraben) to 24.0% (TCS). The limits of quantification (LOQs) varied depending on the target compound and generally ranged from 0.2 to 2.0 ng/mL. The matrix effects ranged from +11 (2,3,4-trihydroxybenzophenone) to -86% (2,4-dihydroxybenzophenone). A total of 30 urine specimens collected from Athens, Greece, were analyzed for the 19 target compounds to demonstrate the applicability of the developed method. The concentrations of target chemicals in urine were presented on volume-, specific gravity (SG)-, and creatinine-normalization bases. MeP, EtP, PrP, OH-EtP, BADGE·2H2O, BP-1 and TCS were found frequently in urine at concentrations in the range of 2.7-436 ng/mL, <0.5-25.4 ng/mL, <0.5-575 ng/mL, <2-18.4 ng/mL, <0.5-13.8 ng/mL, <1-14.6 ng/mL and <0.5-95.3 ng/mL, respectively.
Nikolaos S Thomaidis - One of the best experts on this subject based on the ideXlab platform.
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widespread occurrence of bisphenol a diglycidyl ethers p hydroxybenzoic acid esters Parabens benzophenone type uv filters triclosan and triclocarban in human urine from athens greece
Science of The Total Environment, 2014Co-Authors: Nikolaos S Thomaidis, Alexandros G Asimakopoulos, Kurunthachalam KannanAbstract:Biomonitoring of human exposure to bisphenol A diglycidyl ethers (BADGEs; resin coating for food cans), p-hydroxybenzoic acid esters (Parabens; preservatives), benzophenone-type UV filters (BP-UV filters; sunscreen agents), triclosan (TCS; antimicrobials), and triclocarban (TCC; antimicrobials) has been investigated in western European countries and North America. Nevertheless, little is known about the exposure of Greek populations to these environmental chemicals. In this study, 100 urine samples collected from Athens, Greece, were analyzed by liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the determination of total concentrations of five derivatives of BADGEs, six Parabens and their metabolite (Ethyl-protocatechuate), five derivatives of BP-UV filters, TCS, and TCC. Urinary concentrations of BADGEs, Parabens, Ethyl-protocatechuate, BP-UV filters, TCS and TCC (on a volume basis) ranged 0.3–20.9 (geometric mean: 0.9), 1.6–1010 (24.2), < 2–71.0 (2.1), 0.5–1120 (4.4), < 0.5–2580 (8.0) and < 0.5–1.9 (0.6) ng/mL, respectively. All 19 target chemicals were found in urine, and the highest detection rates were observed for mEthyl Paraben (100%), bisphenol A bis (2,3-dihydroxypropyl) ether (90%), Ethyl Paraben (87%), 2,4-dihydroxybenzophenone (78%), propyl Paraben (72%), and TCS (71%). Estimated daily intakes (EDIurine), calculated on the basis of the measured urinary concentrations, ranged from 0.023 μg/kg bw/day for Σ5BADGEs to 31.4 μg/kg bw/day for Σ6Parabens.
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a multi class bioanalytical methodology for the determination of bisphenol a diglycidyl ethers p hydroxybenzoic acid esters benzophenone type ultraviolet filters triclosan and triclocarban in human urine by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2014Co-Authors: Alexandros G Asimakopoulos, Lei Wang, Nikolaos S Thomaidis, Kurunthachalam KannanAbstract:Abstract A liquid–liquid extraction (LLE; Ethyl acetate) protocol, followed by liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS) methodology, was developed for the determination of 19 compounds, including bisphenol A diglycidyl ethers (BADGEs; industrial ethers), benzophenone-type UV filters (BP-UV filters; precursors and metabolites), p-hydroxybenzoic acid esters (Parabens; preservatives), triclosan (TCS) and triclocarban (TCC) in human urine. Urine specimens were enzymatically deconjugated with β-glucuronidase (from Helix pomatia) and extracted by a LLE procedure for the measurement of total concentrations (i.e., free + conjugated forms) of target analytes. Absolute recoveries of BADGEs, BP-UV filters, Parabens, TCS and TCC ranged 25–135%, 84–125%, 52–126%, 75–118% and 90–124%, respectively. Method precision (absolute values; N = 5 replicate analyses at the fortification level of 10 ng, k = 5 days) ranged from 5.8 (Ethyl Paraben) to 24.0% (TCS). The limits of quantification (LOQs) varied depending on the target compound and generally ranged from 0.2 to 2.0 ng/mL. The matrix effects ranged from +11 (2,3,4-trihydroxybenzophenone) to −86% (2,4-dihydroxybenzophenone). A total of 30 urine specimens collected from Athens, Greece, were analyzed for the 19 target compounds to demonstrate the applicability of the developed method. The concentrations of target chemicals in urine were presented on volume-, specific gravity (SG)-, and creatinine-normalization bases. MeP, EtP, PrP, OH-EtP, BADGE·2H2O, BP-1 and TCS were found frequently in urine at concentrations in the range of 2.7–436 ng/mL,
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a multi class bioanalytical methodology for the determination of bisphenol a diglycidyl ethers p hydroxybenzoic acid esters benzophenone type ultraviolet filters triclosan and triclocarban in human urine by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2014Co-Authors: Alexandros G Asimakopoulos, Lei Wang, Nikolaos S Thomaidis, Kurunthachalam KannanAbstract:A liquid-liquid extraction (LLE; Ethyl acetate) protocol, followed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) methodology, was developed for the determination of 19 compounds, including bisphenol A diglycidyl ethers (BADGEs; industrial ethers), benzophenone-type UV filters (BP-UV filters; precursors and metabolites), p-hydroxybenzoic acid esters (Parabens; preservatives), triclosan (TCS) and triclocarban (TCC) in human urine. Urine specimens were enzymatically deconjugated with β-glucuronidase (from Helix pomatia) and extracted by a LLE procedure for the measurement of total concentrations (i.e., free+conjugated forms) of target analytes. Absolute recoveries of BADGEs, BP-UV filters, Parabens, TCS and TCC ranged 25-135%, 84-125%, 52-126%, 75-118% and 90-124%, respectively. Method precision (absolute values; N=5 replicate analyses at the fortification level of 10 ng, k=5 days) ranged from 5.8 (Ethyl Paraben) to 24.0% (TCS). The limits of quantification (LOQs) varied depending on the target compound and generally ranged from 0.2 to 2.0 ng/mL. The matrix effects ranged from +11 (2,3,4-trihydroxybenzophenone) to -86% (2,4-dihydroxybenzophenone). A total of 30 urine specimens collected from Athens, Greece, were analyzed for the 19 target compounds to demonstrate the applicability of the developed method. The concentrations of target chemicals in urine were presented on volume-, specific gravity (SG)-, and creatinine-normalization bases. MeP, EtP, PrP, OH-EtP, BADGE·2H2O, BP-1 and TCS were found frequently in urine at concentrations in the range of 2.7-436 ng/mL, <0.5-25.4 ng/mL, <0.5-575 ng/mL, <2-18.4 ng/mL, <0.5-13.8 ng/mL, <1-14.6 ng/mL and <0.5-95.3 ng/mL, respectively.
Dionissios Mantzavinos - One of the best experts on this subject based on the ideXlab platform.
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boron doped diamond electrooxidation of Ethyl Paraben the effect of electrolyte on by products distribution and mechanisms
Journal of Environmental Management, 2017Co-Authors: Zacharias Frontistis, Maria Antonopoulou, Melis Yazirdagi, Zeynep Kilinc, Ioannis Konstantinou, Alexandros Katsaounis, Dionissios MantzavinosAbstract:Ethyl Paraben (EP), a representative emerging pollutant of the Parabens family, was subject to electrochemical oxidation over a boron-doped diamond (BDD) anode. Experiments were carried out in a single-compartment cell at 10-70 mA cm-2 current density, 200-600 μg L-1 EP concentration, initial solution pH 3-9 and 0.1 M electrolyte concentration. The degradation rate is favored at increased current densities and in the presence of NaCl as the supporting electrolyte, while the pH effect is inconsiderable. For instance, the first order rate constant for the degradation of 200 μg L-1 EP at 30 mA cm-2 was 0.25, 0.1 and 0.07 min-1 with NaCl, Na2SO4 and HClO4, respectively. Degradation in secondary treated wastewater was faster than in pure water presumably due to the action of chloride ions present in the effluent. Liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) was employed to determine major transformation by-products (TBPs). The route of EP degradation with Na2SO4 involves hydroxylation and demEthylation reactions, signifying the role of electrogenerated hydroxyl radicals in the process. Twenty one TBPs were identified with NaCl as the electrolyte, including several chlorinated and non-chlorinated dimers and trimers; these findings suggest that indirect oxidation mediated by chlorine radicals and other chlorine active species also takes place. In this view, the role of the supporting electrolyte is crucial since it can influence both reaction kinetics and pathways.
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photodegradation of Ethyl Paraben using simulated solar radiation and ag3po4 photocatalyst
Journal of Hazardous Materials, 2017Co-Authors: Zacharias Frontistis, Maria Antonopoulou, Ioannis Konstantinou, Athanasia Petala, Dimitris I Kondarides, Danae Venieri, Dionissios MantzavinosAbstract:In this work, the solar light-induced photocatalytic degradation of Ethyl Paraben (EP), a representative of the Parabens family, was studied using silver orthophosphate, a relatively new photocatalytic material. The catalyst was synthesized by a precipitation method and had a primary crystallite size of ca 70nm, specific surface area of 1.4m2/g and a bandgap of 2.4eV. A factorial design methodology was implemented to evaluate the importance of EP concentration (500-1500μg/L), catalyst concentration (100-500mg/L), reaction time (4-30min), water matrix (pure water or 10mg/L humic acid) and initial solution pH (3-9) on EP removal. All individual effects but solution pH were statistically significant and so were the second-order interactions of EP concentration with reaction time or catalyst concentration. The water matrix effect was negative (all other effects were positive) signifying the role of humic acid as scavenger of the oxidant species. Liquid chromatography-time of flight mass spectrometry revealed the formation of mEthyl Paraben, 4-hydroxybenzoic acid, benzoic acid and phenol as primary transformation by-products; these are formed through dealkylation and decarboxylation reactions initiated primarily by the photogenerated holes. Estrogenicity assays showed that mEthyl Paraben was more estrogenic than EP; however, Parabens are slightly estrogenic compared to 17β-estradiol.
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solar light induced degradation of Ethyl Paraben with cuox bivo4 statistical evaluation of operating factors and transformation by products
Catalysis Today, 2017Co-Authors: Athanasia Petala, Zacharias Frontistis, Maria Antonopoulou, Ioannis Konstantinou, Remi Bontemps, Antoine Spartatouille, Dimitris I Kondarides, Dionissios MantzavinosAbstract:Abstract In this work, the solar light-induced photocatalytic degradation of Ethyl Paraben (EP) was studied using CuOx/BiVO4 with 0.75 wt.% copper loading, a relatively new photocatalyst that can exploit a large portion of the solar spectrum. The synthesized catalyst had a primary crystallite size of ca 37 nm, a specific surface area of 1 m2/g and a direct bandgap of 2.3 eV. A factorial design methodology was implemented to evaluate the importance of EP concentration (500–1500 μg/L), catalyst concentration (100–500 mg/L), reaction time (10–60 min), the presence of radical scavengers (pure water or 500 mg/L bicarbonates) and initial solution pH (3–9) on EP removal. All individual effects were statistically significant and so was the second-order interaction of EP concentration with reaction time. Interestingly and differently from the majority of photocatalytic studies, the presence of bicarbonates promotes the photocatalytic degradation of Ethyl Paraben. The photocatalytic activity drops from 98% to 79% after five consecutive runs, possibly due to accumulation of oxidation by-products. Liquid chromatography-time of flight mass spectrometry (LC-TOF-MS) revealed that EP degradation occurs mainly via dealkylation followed by hydroxylation reactions and the formation of mEthyl Paraben, 4-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid and 3,4-dihydroxybenzoic acid as primary transformation by-products.
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sonochemical degradation of Ethyl Paraben in environmental samples statistically important parameters determining kinetics by products and pathways
Ultrasonics Sonochemistry, 2016Co-Authors: Costas Papadopoulos, Zacharias Frontistis, Maria Antonopoulou, Ioannis Konstantinou, Danae Venieri, Dionissios MantzavinosAbstract:Abstract The sonochemical degradation of Ethyl Paraben (EP), a representative of the Parabens family, was investigated. Experiments were conducted at constant ultrasound frequency of 20 kHz and liquid bulk temperature of 30 °C in the following range of experimental conditions: EP concentration 250–1250 μg/L, ultrasound (US) density 20–60 W/L, reaction time up to 120 min, initial pH 3–8 and sodium persulfate 0–100 mg/L, either in ultrapure water or secondary treated wastewater. A factorial design methodology was adopted to elucidate the statistically important effects and their interactions and a full empirical model comprising seventeen terms was originally developed. Omitting several terms of lower significance, a reduced model that can reliably simulate the process was finally proposed; this includes EP concentration, reaction time, power density and initial pH, as well as the interactions (EP concentration) × (US density), (EP concentration) × (pHo) and (EP concentration) × (time). Experiments at an increased EP concentration of 3.5 mg/L were also performed to identify degradation by-products. LC–TOF–MS analysis revealed that EP sonochemical degradation occurs through dealkylation of the Ethyl chain to form mEthyl Paraben, while successive hydroxylation of the aromatic ring yields 4-hydroxybenzoic, 2,4-dihydroxybenzoic and 3,4-dihydroxybenzoic acids. By-products are less toxic to bacterium V. fischeri than the parent compound.
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kinetics of Ethyl Paraben degradation by simulated solar radiation in the presence of n doped tio2 catalysts
Water Research, 2015Co-Authors: Athanasia Petala, Zacharias Frontistis, Maria Antonopoulou, Ioannis Konstantinou, Dimitris I Kondarides, Dionissios MantzavinosAbstract:Abstract Ethyl Paraben (EP), an emerging micro-pollutant representative of the Parabens family, has been subject to photocatalytic degradation under simulated solar radiation at a photon flux of 1.3·10 −4 E/(m 2 s). Six nitrogen-doped titania catalysts synthesized by annealing a sol–gel derived TiO 2 powder under ammonia flow and their un-doped counterparts, calcined in air at different temperatures in the range 450–800 °C, were compared under solar and visible light and the most active one (N-doped TiO 2 calcined at 600 °C) was used for further tests. Experiments were performed at EP concentrations between 150 and 900 μg/L, catalyst loadings between 100 and 1000 mg/L, pH between 3 and 9, different matrices (ultrapure water, water spiked with humic acids or bicarbonates, drinking water and secondary treated wastewater) and hydrogen peroxide between 10 and 100 mg/L. For EP concentrations up to 300 μg/L, the degradation rate can be approached by first order kinetics but then shifts to lower order as the concentration increases. The rate increases linearly with catalyst loading up to 750 mg/L and hydrogen peroxide up to 100 mg/L. Near-neutral (pH = 6.5–7.5) and alkaline conditions (pH = 9) do not affect degradation, which is reduced at acidic pH. The presence of humic acids at 10–20 mg/L impedes degradation due to the competition with EP for the oxidizing species and this is more pronounced in actual wastewater matrices. UPLC-ESI-HRMS and HPLC-DAD were employed to follow EP concentration changes, as well as identify and quantify transformation by-products during the early stages of the reaction. Five such products were successfully detected and, based on their concentration–time profiles, a reaction network for the degradation of EP is proposed. Hydroxyl radical reactions appear to prevail during the initial steps as evidenced by the rapid formation of hydroxylated and dealkylated intermediates.
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occurrence and profile characteristics of the pesticide imidacloprid preservative Parabens and their metabolites in human urine from rural and urban china
Environmental Science & Technology, 2015Co-Authors: Lei Wang, Fang Liu, Tianzhen Liu, Junjie Zhang, Hongwen SunAbstract:Knowledge of human exposure to imidacloprid, the most extensively used insecticide, and para-hydroxybenzoic acid esters (Parabens), the most extensively used preservative, is insufficient. In this study, 295 urine samples collected from subjects in rural and urban areas in China were analyzed for imidacloprid and four Parabens (namely, mEthyl Paraben, Ethyl Paraben, propyl Paraben, and butyl Paraben) as well as their major metabolites (namely, 6-chloronicotinic acid (6-ClNA) and para-hydroxybenzoic acid (p-HB)). Imidacloprid was detected in 100% of the urine samples from rural Chinese subjects and 95% of the urine samples from urban Chinese subjects. Concentrations of urinary imidacloprid detected in rural Chinese subjects (geometric mean (GM) = 0.18 ng/mL) were slightly higher than those detected in urban Chinese subjects (GM = 0.15 ng/mL) when the effect of pesticide spraying was excluded. However, concentrations of urinary imidacloprid detected in rural adults increased significantly in the subsequent days of pesticide spraying (GM = 0.62 ng/mL), which could return to the normal levels within 3 days. In contrast, concentrations of urinary Parabens detected in rural Chinese subjects (GM = 6.90 ng/mL) were lower than that in urban Chinese subjects (GM = 30.5 ng/mL). In addition, the metabolism characteristics of imidacloprid to 6-ClNA and Parabens to p-HB were discussed preliminarily.
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Occurrence and Profile Characteristics of the Pesticide Imidacloprid, Preservative Parabens, and Their Metabolites in Human Urine from Rural and Urban China
2015Co-Authors: Lei Wang, Fang Liu, Tianzhen Liu, Junjie Zhang, Hongwen SunAbstract:Knowledge of human exposure to imidacloprid, the most extensively used insecticide, and para-hydroxybenzoic acid esters (Parabens), the most extensively used preservative, is insufficient. In this study, 295 urine samples collected from subjects in rural and urban areas in China were analyzed for imidacloprid and four Parabens (namely, mEthyl Paraben, Ethyl Paraben, propyl Paraben, and butyl Paraben) as well as their major metabolites (namely, 6-chloronicotinic acid (6-ClNA) and para-hydroxybenzoic acid (p-HB)). Imidacloprid was detected in 100% of the urine samples from rural Chinese subjects and 95% of the urine samples from urban Chinese subjects. Concentrations of urinary imidacloprid detected in rural Chinese subjects (geometric mean (GM) = 0.18 ng/mL) were slightly higher than those detected in urban Chinese subjects (GM = 0.15 ng/mL) when the effect of pesticide spraying was excluded. However, concentrations of urinary imidacloprid detected in rural adults increased significantly in the subsequent days of pesticide spraying (GM = 0.62 ng/mL), which could return to the normal levels within 3 days. In contrast, concentrations of urinary Parabens detected in rural Chinese subjects (GM = 6.90 ng/mL) were lower than that in urban Chinese subjects (GM = 30.5 ng/mL). In addition, the metabolism characteristics of imidacloprid to 6-ClNA and Parabens to p-HB were discussed preliminarily
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a multi class bioanalytical methodology for the determination of bisphenol a diglycidyl ethers p hydroxybenzoic acid esters benzophenone type ultraviolet filters triclosan and triclocarban in human urine by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2014Co-Authors: Alexandros G Asimakopoulos, Lei Wang, Nikolaos S Thomaidis, Kurunthachalam KannanAbstract:Abstract A liquid–liquid extraction (LLE; Ethyl acetate) protocol, followed by liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS) methodology, was developed for the determination of 19 compounds, including bisphenol A diglycidyl ethers (BADGEs; industrial ethers), benzophenone-type UV filters (BP-UV filters; precursors and metabolites), p-hydroxybenzoic acid esters (Parabens; preservatives), triclosan (TCS) and triclocarban (TCC) in human urine. Urine specimens were enzymatically deconjugated with β-glucuronidase (from Helix pomatia) and extracted by a LLE procedure for the measurement of total concentrations (i.e., free + conjugated forms) of target analytes. Absolute recoveries of BADGEs, BP-UV filters, Parabens, TCS and TCC ranged 25–135%, 84–125%, 52–126%, 75–118% and 90–124%, respectively. Method precision (absolute values; N = 5 replicate analyses at the fortification level of 10 ng, k = 5 days) ranged from 5.8 (Ethyl Paraben) to 24.0% (TCS). The limits of quantification (LOQs) varied depending on the target compound and generally ranged from 0.2 to 2.0 ng/mL. The matrix effects ranged from +11 (2,3,4-trihydroxybenzophenone) to −86% (2,4-dihydroxybenzophenone). A total of 30 urine specimens collected from Athens, Greece, were analyzed for the 19 target compounds to demonstrate the applicability of the developed method. The concentrations of target chemicals in urine were presented on volume-, specific gravity (SG)-, and creatinine-normalization bases. MeP, EtP, PrP, OH-EtP, BADGE·2H2O, BP-1 and TCS were found frequently in urine at concentrations in the range of 2.7–436 ng/mL,
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a multi class bioanalytical methodology for the determination of bisphenol a diglycidyl ethers p hydroxybenzoic acid esters benzophenone type ultraviolet filters triclosan and triclocarban in human urine by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2014Co-Authors: Alexandros G Asimakopoulos, Lei Wang, Nikolaos S Thomaidis, Kurunthachalam KannanAbstract:A liquid-liquid extraction (LLE; Ethyl acetate) protocol, followed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) methodology, was developed for the determination of 19 compounds, including bisphenol A diglycidyl ethers (BADGEs; industrial ethers), benzophenone-type UV filters (BP-UV filters; precursors and metabolites), p-hydroxybenzoic acid esters (Parabens; preservatives), triclosan (TCS) and triclocarban (TCC) in human urine. Urine specimens were enzymatically deconjugated with β-glucuronidase (from Helix pomatia) and extracted by a LLE procedure for the measurement of total concentrations (i.e., free+conjugated forms) of target analytes. Absolute recoveries of BADGEs, BP-UV filters, Parabens, TCS and TCC ranged 25-135%, 84-125%, 52-126%, 75-118% and 90-124%, respectively. Method precision (absolute values; N=5 replicate analyses at the fortification level of 10 ng, k=5 days) ranged from 5.8 (Ethyl Paraben) to 24.0% (TCS). The limits of quantification (LOQs) varied depending on the target compound and generally ranged from 0.2 to 2.0 ng/mL. The matrix effects ranged from +11 (2,3,4-trihydroxybenzophenone) to -86% (2,4-dihydroxybenzophenone). A total of 30 urine specimens collected from Athens, Greece, were analyzed for the 19 target compounds to demonstrate the applicability of the developed method. The concentrations of target chemicals in urine were presented on volume-, specific gravity (SG)-, and creatinine-normalization bases. MeP, EtP, PrP, OH-EtP, BADGE·2H2O, BP-1 and TCS were found frequently in urine at concentrations in the range of 2.7-436 ng/mL, <0.5-25.4 ng/mL, <0.5-575 ng/mL, <2-18.4 ng/mL, <0.5-13.8 ng/mL, <1-14.6 ng/mL and <0.5-95.3 ng/mL, respectively.