Quantification of biodegradation rate of hydrocarbons in a contaminated aquifer by CO2 δ13C monitoring at ground surface.

Ground surface analysis of CO2 emissions with δ13C determination is experimentally demonstrated to be a potential methodology to monitor, on line, the dynamics of petroleum-hydrocarbon biodegradation in soil aquifers, thanks to the improvement of the Isotopic Ratio Infra Red Spectroscopy technique. Biodegradation rate of remaining hydrocarbon substrates in groundwater can be quantified using basic application of the Rayleigh equations, by δ13CCO2 analysis released at ground surface above the pollution plume instead of usual approaches based on groundwater hydrocarbons δ13C analysis, when physical and chemical properties for the contaminated site meet appropriate conditions. The validation approach for that gasoline contaminated specific site is discussed and verified by comparison of first order attenuation rate constant determined from δ13CCO2 analysis emitted at ground surface and from δ13CTOLUENE analysis in ground water. A kinetic fractionation factor α of 0.9979 (or ε value of -2.1 ± 0.5‰) is estimated for the biodegradation of the most reactive hydrocarbon substrates (TEX). The treatment of this Rayleigh equations by linear regression of δ13CCO2 values along the predominant direction of groundwater flow leads to the following results and conclusions for that site: (i) first order biodegradation rate constants (and annual variation) are maximum after the activation of a Permeable Reactive Barrier (PRB) in May 2014: 0.92(+0.29-0.17) year-1, and during July and October: 0.46(+0.14-0.09) year-1 and minimum in mid-winter in February 2015: 0.17(+0.05-0.03) year-1, given by the estimation range for ε. These results are in the lower range with reported in literature for similar contaminated sites (1.6-18 year-1) considering natural attenuation under sulfate reducing conditions and (ii) the seasonal variation of the first order biodegradation rate constant is mainly correlated with the seasonal variation of the CO2 flux, where maximum values are in summers and minimum values in winters. Both seasonal variations are mainly due to the annual cycle of the natural biodegradation activity at the scale of the pollution plume, rather than the activation of the PRB. This work demonstrates that δ13CCO2 analysis released at ground surface from biodegradation of groundwater hydrocarbons could provide, under characterized and appropriate conditions, a non-intrusive (without soil samplings), fast, and low-cost online method to monitor and therefore to optimize soil remediation processes in real time. (Monitored Natural Attenuation or Enhanced Bioremediation).

Impact of meteorological and social events on human-excreted contaminant loads in raw wastewater: From daily to weekly dynamics.

The temporal dynamics of the wastewater influent loads of 25 drug target residues (DTR, both pharmaceuticals and illicit drugs) was assessed during 84 consecutive days. This monitoring scale enables longer temporal patterns than weekday/weekend patterns to be explored. In this study, we focus on day to day variations and the potential statistical correlation of each DTR analyzed in order to better understand the potential forcings that lead to the load variation of DTRs (alone or in clusters). The weekly patterns based on the weekly loads of DTRs were also analyzed and the impact of social and meteorological events on their variations was investigated. Two cold events occurred during the monitoring period and were associated with the highest loads of analgesics and non-steroidal anti-inflammatory drugs, as well as the lowest loads of stimulants. During the Easter holidays, a significant decrease in some year-long medication as well as analgesics was found, consistent with the demographic decrease within the catchment during this period. Lastly, a good correlation between the academic calendar and the loads of stimulants was found, emphasizing the overrepresentation of students in the consumption of recreational drugs. This study furnishes new insights in order to better understand the variations in DTR loads in wastewater influents, beyond the weekday/weekend pattern and the seasonal effect. Further investigations remain necessary, especially a real-time monitoring of the population figures within the catchment in order to improve our understanding of these results.

Temporal dynamics of human-excreted pollutants in wastewater treatment plant influents: Toward a better knowledge of mass load fluctuations.

The occurrence of 25 drug target residues (illicit drugs or pharmaceutically active compounds) was investigated during 85 consecutive days in the influents of a wastewater treatment plant in the Region Centre-Val de Loire, France. This long tracking period allowed a better understanding of the patterns affecting the occurrence of this type of contaminants. Among them, 2 were never detected (i.e. heroin and amphetamine). Concerning illicit drugs two patterns were found. Cocaine and ecstasy median loads varied considerably between weekdays and weekend days (i.e. 18.3 and 35.9% respectively) whereas cannabis and heroin (based on 6-mono-acetylmorphine loads) loads were within the same order of magnitude with a significant statistical correlation with pharmaceuticals such as acetaminophen or ketoprofen. The consumption of selected drugs was back-calculated from the loads. Among illicit drugs the highest consumption was found for cannabis with a median consumption of 51mg·day-1·inhabitant-1 (inh) whereas the median consumption for cocaine (based on benzoylecgonine loads) and ecstasy was 32 and 6mg·day-1·103·inh-1 respectively. The highest consumption values of pharmaceutically active compounds (PACs) were found for acetaminophen and acetylsalicylic acid with 108.8 and 34.1mg·day-1·inh-1 respectively, in good agreement with national sales data. A statistically significant weekly pattern was found for several PACs such as metoprolol and trimethoprim, but with the opposite pattern to that of illicit drugs. The variations in daily PAC loads could provide information about the mobility of people in the catchment, especially on the basis of daily taken PACs (i.e. to treat chronicle diseases).

Variation in δD values of a single, species-specific molecular biomarker: a study of miliacin throughout a field of broomcorn millet (Panicum miliaceum L.).

Compound-specific δD analyses of land plant-derived biomarkers preserved in lake sediments are gaining increasing interest in paleoclimatic studies because of their potential to record essential information on the climatic conditions that prevailed at the time of their synthesis. The accuracy of inferences about climate from these analyses could be better constrained with more study of the variability in the δD values of possible inputs at catchment scales. We measured the δD values of miliacin (olean-18-en-3ß-ol methyl ether) extracted from the seeds of millet plants collected in 21 stands spatially distributed in a field with visually heterogeneous soil organic matter contents. The use of a single molecular biomarker extracted from a single plant species eliminates the possibility of variability caused by differences in plant type. The δD values differed between plants by as much as 50‰ and the average δD values per stand differed from one another by a maximum of 30‰. Thus, the δD values of a single, species-specific biomarker can vary markedly among plants even within a similar climate. Differences in δD values within stands could be as high as between stands, suggesting that the δD values are not related to macroscale heterogeneities in soil organic matter content. In addition, δD values were unrelated to factors indicative of differences in environment such as plant height, seed weight or miliacin concentration. The average miliacin δD value was representative of the area sampled, however, since it was normally distributed (p < 0.05).

Usefulness of nocturia as a mortality risk factor for coronary heart disease among persons born in 1920 or 1921.

Cardiovascular events are clustered in the morning hours, after increases in blood pressure and heart rate that accompany awakening and arising. Similar hemodynamic changes occur during the night after nocturnal awakening and getting up. Such changes are common among older patients who have nocturia frequently and rise to urinate. We tested the hypothesis that nocturia may be associated with increased mortality in a population sample of 456 subjects born from 1920 to 1921, examined in 1990, and followed for total mortality until 2002. At baseline, they were questioned about nocturia (> or =2 times at night) as part of a detailed questionnaire and examination. Twelve-year survival was significantly lower (61% vs 72%, p = 0.0206) among subjects reporting nocturia (n = 160, 64% men) compared with those without nocturia (n = 296, 50% men). After accounting for numerous confounders, a proportional hazard model determined the mortality hazard ratio (HR) for nocturia alone to be 0.89 (95% confidence interval [CI] 0.55 to 1.43). The interaction between nocturia and previous coronary heart disease (CHD) was highly significant (p <0.0001), with an interaction variable HR of 2.16 (95% CI 1.01 to 4.61). Survival of patients who had CHD with nocturia (n = 54) versus those without nocturia (n = 65) was 44% versus 66% (p = 0.0201). Among patients with CHD, the mortality HR for nocturia was 2.11 (95% CI 1.16 to 4.00). In conclusion, nocturia is a significant independent predictor of mortality among 70-year-old patients with known CHD and thus warrants special attention.

Synthesis and characterization of AP5346, a novel polymer-linked diaminocyclohexyl platinum chemotherapeutic agent.

Syntheses of the novel polymer-bound platinum-based chemotherapeutic agent poly(HPMA)-GGG-Ama=Pt=(1R,2R)-DACH, AP5346, and its precursors are reported. The method utilized in preclinical development of AP5346 is described herein. Additionally, an improved synthesis, which has shown that ion exchange resins can be removed, significantly less platinum can be used when the reaction mixture is pH-stated, and the synthesis can be performed at a higher concentration, is reported. These combined improvements result in a more cost-effective, scaleable procedure. Various methods of analysis of the drug substance are also discussed. Specifically, (1)H NMR spectroscopy is used for identity and can also distinguish small molecule impurities to below 0.1%. (195)Pt NMR determines the coordination environment of the platinum and also identity and purity in relation to platinum chelation of the construct. Size exclusion chromatography is used to establish the molecular weight of AP5346 while ICP-AES determines platinum content and platinum release rates in phosphate-buffered saline. The cumulative results of this work have yielded an efficient syntheses of a polymer-based chemotherapeutic agent with subsequent detailed characterization methods.