Several defense departments intend to replace 2,4,6-trinitrotoluene (TNT) in munitions formulatio... more Several defense departments intend to replace 2,4,6-trinitrotoluene (TNT) in munitions formulations by the less sensitive 2,4-dinitroanisole (DNAN). To help understand environmental behavior and ecological risk associated with DNAN we investigated its key initial abiotic and biotic reaction routes and determined relevant physicochemical parameters (pKa, logKow, aqueous solubility (Sw), partition coefficient (Kd)) for the chemical and its products. Reduction of DNAN with either zero valent iron or bacteria regioselectively produced 2-amino-4-nitroanisole (2-ANAN) which, under strict anaerobic conditions, gave 2,4-diaminoanisole (DAAN). Hydrolysis under environmental conditions was insignificant whereas photolysis gave photodegradable intermediates 2-hydroxy-4-nitroanisole and 2,4-dinitrophenol. Physicochemical properties of DNAN and its amino products drastically depended on the type and position of substituent(s) on the aromatic ring. Sw followed the order (TNT<DNAN<2-ANAN<...
Developing and updating high-quality guidelines requires substantial time and resources. To reduc... more Developing and updating high-quality guidelines requires substantial time and resources. To reduce duplication of effort and enhance efficiency, we developed a process for guideline adaptation and assessed initial perceptions of its feasibility and usefulness. Based on preliminary developments and empirical studies, a series of meetings with guideline experts were organised to define a process for guideline adaptation (ADAPTE) and to develop a manual and a toolkit made available on a website (http://www.adapte.org). Potential users, guideline developers and implementers, were invited to register and to complete a questionnaire evaluating their perception about the proposed process. The ADAPTE process consists of three phases (set-up, adaptation, finalisation), 9 modules and 24 steps. The adaptation phase involves identifying specific clinical questions, searching for, retrieving and assessing available guidelines, and preparing the draft adapted guideline. Among 330 registered indiv...
Water science and technology : a journal of the International Association on Water Pollution Research, 2001
The present study explores the feasibility of biotreatment of 2,4,6-trinitrotoluene (TNT) and hex... more The present study explores the feasibility of biotreatment of 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro- 1,3,5-triazine (RDX)-contaminated soils in slurry batch reactors. Radiorespirometric assays showed that anaerobic sludge was able to mineralize 59% RDX to CO2 although significant mineralization of TNT was not observed in all cases. TNT and RDX at concentrations higher than 50 and 100 mg/L respectively were inhibitory to methanogenesis (used as a bioindicator), however, methanogenesis recovered after TNT was transformed into less toxic triaminotoluene. Bioslurry batch reactors containing 40% of contaminated soil (2000 mg RDX and 1000 mg TNT/kg dry soil) were operated under various conditions. Both TNT and RDX were persistent to soil indigenous microbes. Degradation of both TNT and RDX was enhanced by the municipal sludge amendment, although degradation of RDX was only achieved under anaerobic conditions.
The biotransformation of 2,4,6-trinitrotoluene (TNT) (175 microM) by Phanerochaete chrysosporium ... more The biotransformation of 2,4,6-trinitrotoluene (TNT) (175 microM) by Phanerochaete chrysosporium with molasses and citric acid at pH 4.5 was studied. In less than 2 weeks, TNT disappeared completely, but mineralization (liberated 14CO2) did not exceed 1%. A time study revealed the presence of several intermediates, marked by the initial formation of two monohydroxylaminodinitrotoluenes (2- and 4-HADNT) followed by their successive transformation to several other products, including monoaminodinitrotoluenes (ADNT). A group of nine acylated intermediates were also detected. They included 2-N-acetylamido-4,6-dinitrotoluene and its p isomer, 2-formylamido-4, 6-dinitrotoluene and its p isomer (as acylated ADNT), 4-N-acetylamino-2-amino-6-nitrotoluene and 4-N-formylamido-2-amino-6-nitrotoluene (as acetylated DANT), 4-N-acetylhydroxy-2,6-dinitrotoluene and 4-N-acetoxy-2, 6-dinitrotoluene (as acetylated HADNT), and finally 4-N-acetylamido-2-hydroxylamino-6-nitrotoluene. Furthermore, a fract...
The present study describes the biotransformation of 2,4,6-trinitrotoluene (TNT) (220 microM) by ... more The present study describes the biotransformation of 2,4,6-trinitrotoluene (TNT) (220 microM) by using anaerobic sludge (10%, vol/vol) supplemented with molasses (3.3 g/liter). Despite the disappearance of TNT in less than 15 h, roughly 0.1% of TNT was attributed to mineralization (14CO2). A combination of solid-phase microextraction-gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry identified two distinctive cycles in the degradation of TNT. One cycle was responsible for the stepwise reduction of TNT to eventually produce triaminotoluene (TAT) in relatively high yield (160 microM). The other cycle involved TAT and was responsible for the production of azo derivatives, e.g., 2,2',4,4'-tetraamino-6,6'-azotoluene (2,2',4, 4'-TA-6,6'-azoT) and 2,2',6,6'-tetraamino-4,4'-azotoluene (2,2',6, 6'-TA-4,4'-azoT) at pH 7.2. These azo compounds were also detected when TAT was treated with the anaerobic sludge but not...
ABSTRACT Valorization of lignin into biomaterials requires its good compatibility with the polyme... more ABSTRACT Valorization of lignin into biomaterials requires its good compatibility with the polymeric matrix it is incorporated into. Softwood Kraft lignin was esterified with various anhydrides (acetic, propionic, butyric, methacrylic, maleic) using a solvent-free, catalyst-free, microwave-assisted method. The esterification was fast and efficient (degrees of substitution &gt;90% after 10 min). The reaction was worked up using water or ethanol as purification agent. Esterified lignins were characterized by FT-IR, GPC, quantitative 31P NMR and TGA/DSC. NMR analyses indicated that non-cyclic anhydrides reacted with both aliphatic and phenolic OH groups, while maleic anhydride reacted exclusively with aliphatic OH groups. All acylated lignins except the maleated one showed higher thermal stability than the unmodified lignin. Lignins acylated with non-cyclic anhydrides can be applied as green fillers in apolar polyolefins while maleated lignin can serve as metal adsorbent or macroreagent for the synthesis of polyesters or polyamides. We showed in this study that lignin can be modified in a fast and easy way.
Nitroglycerin (NG) is widely used for the production of explosives and solid propellants, and is ... more Nitroglycerin (NG) is widely used for the production of explosives and solid propellants, and is a soil contaminant of concern at some military training ranges. NG phytotoxicity data reported in the literature cannot be applied directly to development of ecotoxicological benchmarks for plant exposures in soil because they were determined in studies using hydroponic media, cell cultures, and transgenic plants. Toxicities of NG in the present studies were evaluated for alfalfa (Medicago sativa), barnyard grass (Echinochloa crusgalli), and ryegrass (Lolium perenne) exposed to NG in Sassafras sandy loam soil. Uptake and degradation of NG were also evaluated in ryegrass. The median effective concentration values for shoot growth ranged from 40 to 231 mg kg(-1) in studies with NG freshly amended in soil, and from 23 to 185 mg kg(-1) in studies with NG weathered-and-aged in soil. Weathering-and-aging NG in soil did not significantly affect the toxicity based on 95% confidence intervals for either seedling emergence or plant growth endpoints. Uptake studies revealed that NG was not accumulated in ryegrass but was transformed into dinitroglycerin in the soil and roots, and was subsequently translocated into the ryegrass shoots. The highest bioconcentration factors for dinitroglycerin of 685 and 40 were determined for roots and shoots, respectively. Results of these studies will improve our understanding of toxicity and bioconcentration of NG in terrestrial plants and will contribute to ecological risk assessment of NG-contaminated sites.
The high explosive nitroaromatic 2,4-dinitroanisole (DNAN) is less shock sensitive than 2,4,6-tri... more The high explosive nitroaromatic 2,4-dinitroanisole (DNAN) is less shock sensitive than 2,4,6-trinitrotoluene (TNT), and is proposed as a TNT replacement for melt-cast formulations. Before using DNAN in munitions and potentially leading to environmental impact, the present study examines the ecotoxicity of DNAN using selected organisms. In water, DNAN decreased green algae Pseudokirchneriella subcapitata growth (EC50 = 4.0mg/L), and bacteria Vibrio fischeri bioluminescence (Microtox, EC50 = 60.3mg/L). In soil, DNAN decreased perennial ryegrass Lolium perenne growth (EC50 =7 mg/kg), and is lethal to earthworms Eisenia andrei (LC50 = 47 mg/kg). At sub-lethal concentrations, DNAN caused an avoidance response (EC50 = 31 mg/kg) by earthworms. The presence of DNAN and 2-amino-4-nitroanisole in earthworms and plants suggested a role of these compounds in DNAN toxicity. Toxicity of DNAN was compared to TNT, tested under the same experimental conditions. These analyses showed that DNAN was equally, or even less deleterious to organism health than TNT, depending on the species and toxicity test. The present studies provide baseline toxicity data to increase the understanding of the environmental impact of DNAN, and assist science-based decision makers for improved management of potential DNAN contaminated sites.
Several defense departments intend to replace 2,4,6-trinitrotoluene (TNT) in munitions formulatio... more Several defense departments intend to replace 2,4,6-trinitrotoluene (TNT) in munitions formulations by the less sensitive 2,4-dinitroanisole (DNAN). To help understand environmental behavior and ecological risk associated with DNAN we investigated its key initial abiotic and biotic reaction routes and determined relevant physicochemical parameters (pKa, logKow, aqueous solubility (Sw), partition coefficient (Kd)) for the chemical and its products. Reduction of DNAN with either zero valent iron or bacteria regioselectively produced 2-amino-4-nitroanisole (2-ANAN) which, under strict anaerobic conditions, gave 2,4-diaminoanisole (DAAN). Hydrolysis under environmental conditions was insignificant whereas photolysis gave photodegradable intermediates 2-hydroxy-4-nitroanisole and 2,4-dinitrophenol. Physicochemical properties of DNAN and its amino products drastically depended on the type and position of substituent(s) on the aromatic ring. Sw followed the order (TNT<DNAN<2-ANAN<...
Developing and updating high-quality guidelines requires substantial time and resources. To reduc... more Developing and updating high-quality guidelines requires substantial time and resources. To reduce duplication of effort and enhance efficiency, we developed a process for guideline adaptation and assessed initial perceptions of its feasibility and usefulness. Based on preliminary developments and empirical studies, a series of meetings with guideline experts were organised to define a process for guideline adaptation (ADAPTE) and to develop a manual and a toolkit made available on a website (http://www.adapte.org). Potential users, guideline developers and implementers, were invited to register and to complete a questionnaire evaluating their perception about the proposed process. The ADAPTE process consists of three phases (set-up, adaptation, finalisation), 9 modules and 24 steps. The adaptation phase involves identifying specific clinical questions, searching for, retrieving and assessing available guidelines, and preparing the draft adapted guideline. Among 330 registered indiv...
Water science and technology : a journal of the International Association on Water Pollution Research, 2001
The present study explores the feasibility of biotreatment of 2,4,6-trinitrotoluene (TNT) and hex... more The present study explores the feasibility of biotreatment of 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro- 1,3,5-triazine (RDX)-contaminated soils in slurry batch reactors. Radiorespirometric assays showed that anaerobic sludge was able to mineralize 59% RDX to CO2 although significant mineralization of TNT was not observed in all cases. TNT and RDX at concentrations higher than 50 and 100 mg/L respectively were inhibitory to methanogenesis (used as a bioindicator), however, methanogenesis recovered after TNT was transformed into less toxic triaminotoluene. Bioslurry batch reactors containing 40% of contaminated soil (2000 mg RDX and 1000 mg TNT/kg dry soil) were operated under various conditions. Both TNT and RDX were persistent to soil indigenous microbes. Degradation of both TNT and RDX was enhanced by the municipal sludge amendment, although degradation of RDX was only achieved under anaerobic conditions.
The biotransformation of 2,4,6-trinitrotoluene (TNT) (175 microM) by Phanerochaete chrysosporium ... more The biotransformation of 2,4,6-trinitrotoluene (TNT) (175 microM) by Phanerochaete chrysosporium with molasses and citric acid at pH 4.5 was studied. In less than 2 weeks, TNT disappeared completely, but mineralization (liberated 14CO2) did not exceed 1%. A time study revealed the presence of several intermediates, marked by the initial formation of two monohydroxylaminodinitrotoluenes (2- and 4-HADNT) followed by their successive transformation to several other products, including monoaminodinitrotoluenes (ADNT). A group of nine acylated intermediates were also detected. They included 2-N-acetylamido-4,6-dinitrotoluene and its p isomer, 2-formylamido-4, 6-dinitrotoluene and its p isomer (as acylated ADNT), 4-N-acetylamino-2-amino-6-nitrotoluene and 4-N-formylamido-2-amino-6-nitrotoluene (as acetylated DANT), 4-N-acetylhydroxy-2,6-dinitrotoluene and 4-N-acetoxy-2, 6-dinitrotoluene (as acetylated HADNT), and finally 4-N-acetylamido-2-hydroxylamino-6-nitrotoluene. Furthermore, a fract...
The present study describes the biotransformation of 2,4,6-trinitrotoluene (TNT) (220 microM) by ... more The present study describes the biotransformation of 2,4,6-trinitrotoluene (TNT) (220 microM) by using anaerobic sludge (10%, vol/vol) supplemented with molasses (3.3 g/liter). Despite the disappearance of TNT in less than 15 h, roughly 0.1% of TNT was attributed to mineralization (14CO2). A combination of solid-phase microextraction-gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry identified two distinctive cycles in the degradation of TNT. One cycle was responsible for the stepwise reduction of TNT to eventually produce triaminotoluene (TAT) in relatively high yield (160 microM). The other cycle involved TAT and was responsible for the production of azo derivatives, e.g., 2,2',4,4'-tetraamino-6,6'-azotoluene (2,2',4, 4'-TA-6,6'-azoT) and 2,2',6,6'-tetraamino-4,4'-azotoluene (2,2',6, 6'-TA-4,4'-azoT) at pH 7.2. These azo compounds were also detected when TAT was treated with the anaerobic sludge but not...
ABSTRACT Valorization of lignin into biomaterials requires its good compatibility with the polyme... more ABSTRACT Valorization of lignin into biomaterials requires its good compatibility with the polymeric matrix it is incorporated into. Softwood Kraft lignin was esterified with various anhydrides (acetic, propionic, butyric, methacrylic, maleic) using a solvent-free, catalyst-free, microwave-assisted method. The esterification was fast and efficient (degrees of substitution &gt;90% after 10 min). The reaction was worked up using water or ethanol as purification agent. Esterified lignins were characterized by FT-IR, GPC, quantitative 31P NMR and TGA/DSC. NMR analyses indicated that non-cyclic anhydrides reacted with both aliphatic and phenolic OH groups, while maleic anhydride reacted exclusively with aliphatic OH groups. All acylated lignins except the maleated one showed higher thermal stability than the unmodified lignin. Lignins acylated with non-cyclic anhydrides can be applied as green fillers in apolar polyolefins while maleated lignin can serve as metal adsorbent or macroreagent for the synthesis of polyesters or polyamides. We showed in this study that lignin can be modified in a fast and easy way.
Nitroglycerin (NG) is widely used for the production of explosives and solid propellants, and is ... more Nitroglycerin (NG) is widely used for the production of explosives and solid propellants, and is a soil contaminant of concern at some military training ranges. NG phytotoxicity data reported in the literature cannot be applied directly to development of ecotoxicological benchmarks for plant exposures in soil because they were determined in studies using hydroponic media, cell cultures, and transgenic plants. Toxicities of NG in the present studies were evaluated for alfalfa (Medicago sativa), barnyard grass (Echinochloa crusgalli), and ryegrass (Lolium perenne) exposed to NG in Sassafras sandy loam soil. Uptake and degradation of NG were also evaluated in ryegrass. The median effective concentration values for shoot growth ranged from 40 to 231 mg kg(-1) in studies with NG freshly amended in soil, and from 23 to 185 mg kg(-1) in studies with NG weathered-and-aged in soil. Weathering-and-aging NG in soil did not significantly affect the toxicity based on 95% confidence intervals for either seedling emergence or plant growth endpoints. Uptake studies revealed that NG was not accumulated in ryegrass but was transformed into dinitroglycerin in the soil and roots, and was subsequently translocated into the ryegrass shoots. The highest bioconcentration factors for dinitroglycerin of 685 and 40 were determined for roots and shoots, respectively. Results of these studies will improve our understanding of toxicity and bioconcentration of NG in terrestrial plants and will contribute to ecological risk assessment of NG-contaminated sites.
The high explosive nitroaromatic 2,4-dinitroanisole (DNAN) is less shock sensitive than 2,4,6-tri... more The high explosive nitroaromatic 2,4-dinitroanisole (DNAN) is less shock sensitive than 2,4,6-trinitrotoluene (TNT), and is proposed as a TNT replacement for melt-cast formulations. Before using DNAN in munitions and potentially leading to environmental impact, the present study examines the ecotoxicity of DNAN using selected organisms. In water, DNAN decreased green algae Pseudokirchneriella subcapitata growth (EC50 = 4.0mg/L), and bacteria Vibrio fischeri bioluminescence (Microtox, EC50 = 60.3mg/L). In soil, DNAN decreased perennial ryegrass Lolium perenne growth (EC50 =7 mg/kg), and is lethal to earthworms Eisenia andrei (LC50 = 47 mg/kg). At sub-lethal concentrations, DNAN caused an avoidance response (EC50 = 31 mg/kg) by earthworms. The presence of DNAN and 2-amino-4-nitroanisole in earthworms and plants suggested a role of these compounds in DNAN toxicity. Toxicity of DNAN was compared to TNT, tested under the same experimental conditions. These analyses showed that DNAN was equally, or even less deleterious to organism health than TNT, depending on the species and toxicity test. The present studies provide baseline toxicity data to increase the understanding of the environmental impact of DNAN, and assist science-based decision makers for improved management of potential DNAN contaminated sites.
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Papers by Louise Paquet